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Belsley G, Tyler DJ, Robson MD, Tunnicliffe EM. The effect of and correction for through-slice dephasing on 2D gradient-echo double angle B 1 + mapping. Magn Reson Med 2024; 91:1598-1607. [PMID: 38156827 PMCID: PMC10952755 DOI: 10.1002/mrm.29966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 10/24/2023] [Accepted: 11/22/2023] [Indexed: 01/03/2024]
Abstract
PURPOSE To show thatB 0 $$ {\mathrm{B}}_0 $$ variations through slice and slice profile effects are two major confounders affecting 2D dual angleB 1 + $$ {\mathrm{B}}_1^{+} $$ maps using gradient-echo signals and thus need to be corrected to obtain accurateB 1 + $$ {\mathrm{B}}_1^{+} $$ maps. METHODS The 2D gradient-echo transverse complex signal was Bloch-simulated and integrated across the slice dimension including nonlinear variations inB 0 $$ {\mathrm{B}}_0 $$ inhomogeneities through slice. A nonlinear least squares fit was used to find theB 1 + $$ {\mathrm{B}}_1^{+} $$ factor corresponding to the best match between the two gradient-echo signals experimental ratio and the Bloch-simulated ratio. The correction was validated in phantom and in vivo at 3T. RESULTS For our RF excitation pulse, the error in theB 1 + $$ {\mathrm{B}}_1^{+} $$ factor scales by approximately 3.8% for every 10 Hz/cm variation inB 0 $$ {\mathrm{B}}_0 $$ along the slice direction. Higher accuracy phantomB 1 + $$ {\mathrm{B}}_1^{+} $$ maps were obtained after applying the proposed correction; the root mean squareB 1 + $$ {\mathrm{B}}_1^{+} $$ error relative to the gold standardB 1 + $$ {\mathrm{B}}_1^{+} $$ decreased from 6.4% to 2.6%. In vivo whole-liverT 1 $$ {\mathrm{T}}_1 $$ maps using the correctedB 1 + $$ {\mathrm{B}}_1^{+} $$ map registered a significant decrease inT 1 $$ {\mathrm{T}}_1 $$ gradient through slice. CONCLUSION B 0 $$ {\mathrm{B}}_0 $$ inhomogeneities varying through slice were seen to have an impact on the accuracy of 2D double angleB 1 + $$ {\mathrm{B}}_1^{+} $$ maps using gradient-echo sequences. Consideration of this confounder is crucial for research relying on accurate knowledge of the true excitation flip angles, as is the case ofT 1 $$ {\mathrm{T}}_1 $$ mapping using a spoiled gradient recalled echo sequence.
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Affiliation(s)
- Gabriela Belsley
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Damian J. Tyler
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Matthew D. Robson
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
- PerspectumOxfordUK
| | - Elizabeth M. Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
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Moulin K, Stoeck CT, Axel L, Broncano J, Croisille P, Dall'Armellina E, Ennis DB, Ferreira PF, Gotschy A, Miro S, Schneider JE, Scott AD, Sosnovik DE, Teh I, Tous C, Tunnicliffe EM, Viallon M, Nguyen C. In Vivo Cardiac Diffusion Imaging Without Motion-Compensation Leads to Unreasonably High Diffusivity. J Magn Reson Imaging 2023; 58:1990-1991. [PMID: 37000010 DOI: 10.1002/jmri.28703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 04/01/2023] Open
Affiliation(s)
- Kevin Moulin
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Christian T Stoeck
- Institute for Biomedical Engineering, University and ETH, Zurich, Switzerland
- Center for Preclinical Development, University of Zurich and University Hospital Zurich, Zurich, Switzerland
| | - Leon Axel
- Department of Radiology, New York University Grossman School of Medicine, New York City, New York, USA
| | - Jordi Broncano
- Department of Radiology, Hospital San Juan de Dios, Hospital de la Cruz Roja, HT-RESALTA, HT Médica, Córdoba, Spain
| | - Pierre Croisille
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France
- CREATIS UMR CNRS5220 INSERM U1206, University of Lyon, Lyon, France
| | - Erica Dall'Armellina
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Daniel B Ennis
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Pedro F Ferreira
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Alexander Gotschy
- Institute for Biomedical Engineering, University and ETH, Zurich, Switzerland
| | - Santiago Miro
- Department of Radiology, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Quebec, Canada
| | - Jurgen E Schneider
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Andrew D Scott
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK
- National Heart and Lung Institute, Imperial College London, London, UK
| | - David E Sosnovik
- Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Irvin Teh
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Cyril Tous
- Department of Diagnostic and Interventional Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
- Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
| | - Elizabeth M Tunnicliffe
- Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Magalie Viallon
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France
- CREATIS UMR CNRS5220 INSERM U1206, University of Lyon, Lyon, France
| | - Christopher Nguyen
- Cardiovascular Innovation Research Center, Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
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Raman B, McCracken C, Cassar MP, Moss AJ, Finnigan L, Samat AHA, Ogbole G, Tunnicliffe EM, Alfaro-Almagro F, Menke R, Xie C, Gleeson F, Lukaschuk E, Lamlum H, McGlynn K, Popescu IA, Sanders ZB, Saunders LC, Piechnik SK, Ferreira VM, Nikolaidou C, Rahman NM, Ho LP, Harris VC, Shikotra A, Singapuri A, Pfeffer P, Manisty C, Kon OM, Beggs M, O'Regan DP, Fuld J, Weir-McCall JR, Parekh D, Steeds R, Poinasamy K, Cuthbertson DJ, Kemp GJ, Semple MG, Horsley A, Miller CA, O'Brien C, Shah AM, Chiribiri A, Leavy OC, Richardson M, Elneima O, McAuley HJC, Sereno M, Saunders RM, Houchen-Wolloff L, Greening NJ, Bolton CE, Brown JS, Choudhury G, Diar Bakerly N, Easom N, Echevarria C, Marks M, Hurst JR, Jones MG, Wootton DG, Chalder T, Davies MJ, De Soyza A, Geddes JR, Greenhalf W, Howard LS, Jacob J, Man WDC, Openshaw PJM, Porter JC, Rowland MJ, Scott JT, Singh SJ, Thomas DC, Toshner M, Lewis KE, Heaney LG, Harrison EM, Kerr S, Docherty AB, Lone NI, Quint J, Sheikh A, Zheng B, Jenkins RG, Cox E, Francis S, Halling-Brown M, Chalmers JD, Greenwood JP, Plein S, Hughes PJC, Thompson AAR, Rowland-Jones SL, Wild JM, Kelly M, Treibel TA, Bandula S, Aul R, Miller K, Jezzard P, Smith S, Nichols TE, McCann GP, Evans RA, Wain LV, Brightling CE, Neubauer S, Baillie JK, Shaw A, Hairsine B, Kurasz C, Henson H, Armstrong L, Shenton L, Dobson H, Dell A, Lucey A, Price A, Storrie A, Pennington C, Price C, Mallison G, Willis G, Nassa H, Haworth J, Hoare M, Hawkings N, Fairbairn S, Young S, Walker S, Jarrold I, Sanderson A, David C, Chong-James K, Zongo O, James WY, Martineau A, King B, Armour C, McAulay D, Major E, McGinness J, McGarvey L, Magee N, Stone R, Drain S, Craig T, Bolger A, Haggar A, Lloyd A, Subbe C, Menzies D, Southern D, McIvor E, Roberts K, Manley R, Whitehead V, Saxon W, Bularga A, Mills NL, El-Taweel H, Dawson J, Robinson L, Saralaya D, Regan K, Storton K, Brear L, Amoils S, Bermperi A, Elmer A, Ribeiro C, Cruz I, Taylor J, Worsley J, Dempsey K, Watson L, Jose S, Marciniak S, Parkes M, McQueen A, Oliver C, Williams J, Paradowski K, Broad L, Knibbs L, Haynes M, Sabit R, Milligan L, Sampson C, Hancock A, Evenden C, Lynch C, Hancock K, Roche L, Rees M, Stroud N, Thomas-Woods T, Heller S, Robertson E, Young B, Wassall H, Babores M, Holland M, Keenan N, Shashaa S, Price C, Beranova E, Ramos H, Weston H, Deery J, Austin L, Solly R, Turney S, Cosier T, Hazelton T, Ralser M, Wilson A, Pearce L, Pugmire S, Stoker W, McCormick W, Dewar A, Arbane G, Kaltsakas G, Kerslake H, Rossdale J, Bisnauthsing K, Aguilar Jimenez LA, Martinez LM, Ostermann M, Magtoto MM, Hart N, Marino P, Betts S, Solano TS, Arias AM, Prabhu A, Reed A, Wrey Brown C, Griffin D, Bevan E, Martin J, Owen J, Alvarez Corral M, Williams N, Payne S, Storrar W, Layton A, Lawson C, Mills C, Featherstone J, Stephenson L, Burdett T, Ellis Y, Richards A, Wright C, Sykes DL, Brindle K, Drury K, Holdsworth L, Crooks MG, Atkin P, Flockton R, Thackray-Nocera S, Mohamed A, Taylor A, Perkins E, Ross G, McGuinness H, Tench H, Phipps J, Loosley R, Wolf-Roberts R, Coetzee S, Omar Z, Ross A, Card B, Carr C, King C, Wood C, Copeland D, Calvelo E, Chilvers ER, Russell E, Gordon H, Nunag JL, Schronce J, March K, Samuel K, Burden L, Evison L, McLeavey L, Orriss-Dib L, Tarusan L, Mariveles M, Roy M, Mohamed N, Simpson N, Yasmin N, Cullinan P, Daly P, Haq S, Moriera S, Fayzan T, Munawar U, Nwanguma U, Lingford-Hughes A, Altmann D, Johnston D, Mitchell J, Valabhji J, Price L, Molyneaux PL, Thwaites RS, Walsh S, Frankel A, Lightstone L, Wilkins M, Willicombe M, McAdoo S, Touyz R, Guerdette AM, Warwick K, Hewitt M, Reddy R, White S, McMahon A, Hoare A, Knighton A, Ramos A, Te A, Jolley CJ, Speranza F, Assefa-Kebede H, Peralta I, Breeze J, Shevket K, Powell N, Adeyemi O, Dulawan P, Adrego R, Byrne S, Patale S, Hayday A, Malim M, Pariante C, Sharpe C, Whitney J, Bramham K, Ismail K, Wessely S, Nicholson T, Ashworth A, Humphries A, Tan AL, Whittam B, Coupland C, Favager C, Peckham D, Wade E, Saalmink G, Clarke J, Glossop J, Murira J, Rangeley J, Woods J, Hall L, Dalton M, Window N, Beirne P, Hardy T, Coakley G, Turtle L, Berridge A, Cross A, Key AL, Rowe A, Allt AM, Mears C, Malein F, Madzamba G, Hardwick HE, Earley J, Hawkes J, Pratt J, Wyles J, Tripp KA, Hainey K, Allerton L, Lavelle-Langham L, Melling L, Wajero LO, Poll L, Noonan MJ, French N, Lewis-Burke N, Williams-Howard SA, Cooper S, Kaprowska S, Dobson SL, Marsh S, Highett V, Shaw V, Beadsworth M, Defres S, Watson E, Tiongson GF, Papineni P, Gurram S, Diwanji SN, Quaid S, Briggs A, Hastie C, Rogers N, Stensel D, Bishop L, McIvor K, Rivera-Ortega P, Al-Sheklly B, Avram C, Faluyi D, Blaikely J, Piper Hanley K, Radhakrishnan K, Buch M, Hanley NA, Odell N, Osbourne R, Stockdale S, Felton T, Gorsuch T, Hussell T, Kausar Z, Kabir T, McAllister-Williams H, Paddick S, Burn D, Ayoub A, Greenhalgh A, Sayer A, Young A, Price D, Burns G, MacGowan G, Fisher H, Tedd H, Simpson J, Jiwa K, Witham M, Hogarth P, West S, Wright S, McMahon MJ, Neill P, Dougherty A, Morrow A, Anderson D, Grieve D, Bayes H, Fallon K, Mangion K, Gilmour L, Basu N, Sykes R, Berry C, McInnes IB, Donaldson A, Sage EK, Barrett F, Welsh B, Bell M, Quigley J, Leitch K, Macliver L, Patel M, Hamil R, Deans A, Furniss J, Clohisey S, Elliott A, Solstice AR, Deas C, Tee C, Connell D, Sutherland D, George J, Mohammed S, Bunker J, Holmes K, Dipper A, Morley A, Arnold D, Adamali H, Welch H, Morrison L, Stadon L, Maskell N, Barratt S, Dunn S, Waterson S, Jayaraman B, Light T, Selby N, Hosseini A, Shaw K, Almeida P, Needham R, Thomas AK, Matthews L, Gupta A, Nikolaidis A, Dupont C, Bonnington J, Chrystal M, Greenhaff PL, Linford S, Prosper S, Jang W, Alamoudi A, Bloss A, Megson C, Nicoll D, Fraser E, Pacpaco E, Conneh F, Ogg G, McShane H, Koychev I, Chen J, Pimm J, Ainsworth M, Pavlides M, Sharpe M, Havinden-Williams M, Petousi N, Talbot N, Carter P, Kurupati P, Dong T, Peng Y, Burns A, Kanellakis N, Korszun A, Connolly B, Busby J, Peto T, Patel B, Nolan CM, Cristiano D, Walsh JA, Liyanage K, Gummadi M, Dormand N, Polgar O, George P, Barker RE, Patel S, Price L, Gibbons M, Matila D, Jarvis H, Lim L, Olaosebikan O, Ahmad S, Brill S, Mandal S, Laing C, Michael A, Reddy A, Johnson C, Baxendale H, Parfrey H, Mackie J, Newman J, Pack J, Parmar J, Paques K, Garner L, Harvey A, Summersgill C, Holgate D, Hardy E, Oxton J, Pendlebury J, McMorrow L, Mairs N, Majeed N, Dark P, Ugwuoke R, Knight S, Whittaker S, Strong-Sheldrake S, Matimba-Mupaya W, Chowienczyk P, Pattenadk D, Hurditch E, Chan F, Carborn H, Foot H, Bagshaw J, Hockridge J, Sidebottom J, Lee JH, Birchall K, Turner K, Haslam L, Holt L, Milner L, Begum M, Marshall M, Steele N, Tinker N, Ravencroft P, Butcher R, Misra S, Walker S, Coburn Z, Fairman A, Ford A, Holbourn A, Howell A, Lawrie A, Lye A, Mbuyisa A, Zawia A, Holroyd-Hind B, Thamu B, Clark C, Jarman C, Norman C, Roddis C, Foote D, Lee E, Ilyas F, Stephens G, Newell H, Turton H, Macharia I, Wilson I, Cole J, McNeill J, Meiring J, Rodger J, Watson J, Chapman K, Harrington K, Chetham L, Hesselden L, Nwafor L, Dixon M, Plowright M, Wade P, Gregory R, Lenagh R, Stimpson R, Megson S, Newman T, Cheng Y, Goodwin C, Heeley C, Sissons D, Sowter D, Gregory H, Wynter I, Hutchinson J, Kirk J, Bennett K, Slack K, Allsop L, Holloway L, Flynn M, Gill M, Greatorex M, Holmes M, Buckley P, Shelton S, Turner S, Sewell TA, Whitworth V, Lovegrove W, Tomlinson J, Warburton L, Painter S, Vickers C, Redwood D, Tilley J, Palmer S, Wainwright T, Breen G, Hotopf M, Dunleavy A, Teixeira J, Ali M, Mencias M, Msimanga N, Siddique S, Samakomva T, Tavoukjian V, Forton D, Ahmed R, Cook A, Thaivalappil F, Connor L, Rees T, McNarry M, Williams N, McCormick J, McIntosh J, Vere J, Coulding M, Kilroy S, Turner V, Butt AT, Savill H, Fraile E, Ugoji J, Landers G, Lota H, Portukhay S, Nasseri M, Daniels A, Hormis A, Ingham J, Zeidan L, Osborne L, Chablani M, Banerjee A, David A, Pakzad A, Rangelov B, Williams B, Denneny E, Willoughby J, Xu M, Mehta P, Batterham R, Bell R, Aslani S, Lilaonitkul W, Checkley A, Bang D, Basire D, Lomas D, Wall E, Plant H, Roy K, Heightman M, Lipman M, Merida Morillas M, Ahwireng N, Chambers RC, Jastrub R, Logan S, Hillman T, Botkai A, Casey A, Neal A, Newton-Cox A, Cooper B, Atkin C, McGee C, Welch C, Wilson D, Sapey E, Qureshi H, Hazeldine J, Lord JM, Nyaboko J, Short J, Stockley J, Dasgin J, Draxlbauer K, Isaacs K, Mcgee K, Yip KP, Ratcliffe L, Bates M, Ventura M, Ahmad Haider N, Gautam N, Baggott R, Holden S, Madathil S, Walder S, Yasmin S, Hiwot T, Jackson T, Soulsby T, Kamwa V, Peterkin Z, Suleiman Z, Chaudhuri N, Wheeler H, Djukanovic R, Samuel R, Sass T, Wallis T, Marshall B, Childs C, Marouzet E, Harvey M, Fletcher S, Dickens C, Beckett P, Nanda U, Daynes E, Charalambou A, Yousuf AJ, Lea A, Prickett A, Gooptu B, Hargadon B, Bourne C, Christie C, Edwardson C, Lee D, Baldry E, Stringer E, Woodhead F, Mills G, Arnold H, Aung H, Qureshi IN, Finch J, Skeemer J, Hadley K, Khunti K, Carr L, Ingram L, Aljaroof M, Bakali M, Bakau M, Baldwin M, Bourne M, Pareek M, Soares M, Tobin M, Armstrong N, Brunskill N, Goodman N, Cairns P, Haldar P, McCourt P, Dowling R, Russell R, Diver S, Edwards S, Glover S, Parker S, Siddiqui S, Ward TJC, Mcnally T, Thornton T, Yates T, Ibrahim W, Monteiro W, Thickett D, Wilkinson D, Broome M, McArdle P, Upthegrove R, Wraith D, Langenberg C, Summers C, Bullmore E, Heeney JL, Schwaeble W, Sudlow CL, Adeloye D, Newby DE, Rudan I, Shankar-Hari M, Thorpe M, Pius R, Walmsley S, McGovern A, Ballard C, Allan L, Dennis J, Cavanagh J, Petrie J, O'Donnell K, Spears M, Sattar N, MacDonald S, Guthrie E, Henderson M, Guillen Guio B, Zhao B, Lawson C, Overton C, Taylor C, Tong C, Mukaetova-Ladinska E, Turner E, Pearl JE, Sargant J, Wormleighton J, Bingham M, Sharma M, Steiner M, Samani N, Novotny P, Free R, Allen RJ, Finney S, Terry S, Brugha T, Plekhanova T, McArdle A, Vinson B, Spencer LG, Reynolds W, Ashworth M, Deakin B, Chinoy H, Abel K, Harvie M, Stanel S, Rostron A, Coleman C, Baguley D, Hufton E, Khan F, Hall I, Stewart I, Fabbri L, Wright L, Kitterick P, Morriss R, Johnson S, Bates A, Antoniades C, Clark D, Bhui K, Channon KM, Motohashi K, Sigfrid L, Husain M, Webster M, Fu X, Li X, Kingham L, Klenerman P, Miiler K, Carson G, Simons G, Huneke N, Calder PC, Baldwin D, Bain S, Lasserson D, Daines L, Bright E, Stern M, Crisp P, Dharmagunawardena R, Reddington A, Wight A, Bailey L, Ashish A, Robinson E, Cooper J, Broadley A, Turnbull A, Brookes C, Sarginson C, Ionita D, Redfearn H, Elliott K, Barman L, Griffiths L, Guy Z, Gill R, Nathu R, Harris E, Moss P, Finnigan J, Saunders K, Saunders P, Kon S, Kon SS, O'Brien L, Shah K, Shah P, Richardson E, Brown V, Brown M, Brown J, Brown J, Brown A, Brown A, Brown M, Choudhury N, Jones S, Jones H, Jones L, Jones I, Jones G, Jones H, Jones D, Davies F, Davies E, Davies K, Davies G, Davies GA, Howard K, Porter J, Rowland J, Rowland A, Scott K, Singh S, Singh C, Thomas S, Thomas C, Lewis V, Lewis J, Lewis D, Harrison P, Francis C, Francis R, Hughes RA, Hughes J, Hughes AD, Thompson T, Kelly S, Smith D, Smith N, Smith A, Smith J, Smith L, Smith S, Evans T, Evans RI, Evans D, Evans R, Evans H, Evans J. Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study. Lancet Respir Med 2023; 11:1003-1019. [PMID: 37748493 PMCID: PMC7615263 DOI: 10.1016/s2213-2600(23)00262-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 06/16/2023] [Accepted: 06/30/2023] [Indexed: 09/27/2023]
Abstract
INTRODUCTION The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. METHODS In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. FINDINGS Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. INTERPRETATION After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification. FUNDING UK Research and Innovation and National Institute for Health Research.
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Pavlides M, Mózes FE, Akhtar S, Wonders K, Cobbold J, Tunnicliffe EM, Allison M, Godfrey EM, Aithal GP, Francis S, Romero-Gomez M, Castell J, Fernandez-Lizaranzu I, Aller R, González RS, Agustin S, Pericàs JM, Boursier J, Aube C, Ratziu V, Wagner M, Petta S, Antonucci M, Bugianesi E, Faletti R, Miele L, Geier A, Schattenberg JM, Tilman E, Ekstedt M, Lundberg P, Berzigotti A, Huber AT, Papatheodoridis G, Yki-Järvinen H, Porthan K, Schneider MJ, Hockings P, Shumbayawonda E, Banerjee R, Pepin K, Kalutkiewicz M, Ehman RL, Trylesinksi A, Coxson HO, Martic M, Yunis C, Tuthill T, Bossuyt PM, Anstee QM, Neubauer S, Harrison S. Liver Investigation: Testing Marker Utility in Steatohepatitis (LITMUS): Assessment & validation of imaging modality performance across the NAFLD spectrum in a prospectively recruited cohort study (the LITMUS imaging study): Study protocol. Contemp Clin Trials 2023; 134:107352. [PMID: 37802221 DOI: 10.1016/j.cct.2023.107352] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/29/2023] [Accepted: 10/01/2023] [Indexed: 10/08/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the liver manifestation of the metabolic syndrome with global prevalence reaching epidemic levels. Despite the high disease burden in the population only a small proportion of those with NAFLD will develop progressive liver disease, for which there is currently no approved pharmacotherapy. Identifying those who are at risk of progressive NAFLD currently requires a liver biopsy which is problematic. Firstly, liver biopsy is invasive and therefore not appropriate for use in a condition like NAFLD that affects a large proportion of the population. Secondly, biopsy is limited by sampling and observer dependent variability which can lead to misclassification of disease severity. Non-invasive biomarkers are therefore needed to replace liver biopsy in the assessment of NAFLD. Our study addresses this unmet need. The LITMUS Imaging Study is a prospectively recruited multi-centre cohort study evaluating magnetic resonance imaging and elastography, and ultrasound elastography against liver histology as the reference standard. Imaging biomarkers and biopsy are acquired within a 100-day window. The study employs standardised processes for imaging data collection and analysis as well as a real time central monitoring and quality control process for all the data submitted for analysis. It is anticipated that the high-quality data generated from this study will underpin changes in clinical practice for the benefit of people with NAFLD. Study Registration: clinicaltrials.gov: NCT05479721.
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Affiliation(s)
- Michael Pavlides
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Translational Gastroenterology Unit, University of Oxford, Oxford, UK; Oxford NIHR Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust and the University of Oxford, Oxford, UK.
| | - Ferenc E Mózes
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Salma Akhtar
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Kristy Wonders
- Translational & Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom; Newcastle NIHR Biomedical Research Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Jeremy Cobbold
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK; Oxford NIHR Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust and the University of Oxford, Oxford, UK
| | - Elizabeth M Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Oxford NIHR Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust and the University of Oxford, Oxford, UK
| | - Michael Allison
- Liver Unit, Department of Medicine, Cambridge NIHR Biomedical Research Centre, Cambridge University NHS Foundation Trust, UK
| | - Edmund M Godfrey
- Department of Radiology, Cambridge University NHS Foundation Trust, Cambridge, UK
| | - Guruprasad P Aithal
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - Susan Francis
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, UK
| | - Manuel Romero-Gomez
- Digestive Diseases Unit, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Javier Castell
- Radiodiagnosis Clinical Management Unit, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | | | - Rocio Aller
- Department of Gastroenterology, Clinic University Hospital, Medical School, University of Valladolid, CIBERINFEC, Valladolid, Spain
| | - Rebeca Sigüenza González
- Department of Radiology, Clinic University Hospital, Medical School, University of Valladolid, Valladolid, Spain
| | - Salvador Agustin
- Liver Unit, Vall d'Hebron Institut de Recerca, Vall d'Hebron Barcelona Hospital, Centros de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Juan M Pericàs
- Liver Unit, Vall d'Hebron Institut de Recerca, Vall d'Hebron Barcelona Hospital, Centros de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Jerome Boursier
- Centre Hospitalier Universitaire d'Angers, Angers, France; & Laboratoire HIFIH UPRES EA3859, Université d'Angers, Angers, France
| | - Christophe Aube
- Department of Radiology, Centre Hospitalier Universitaire d'Angers, Angers, France; & Laboratoire HIFIH UPRES EA3859, Université d'Angers, Angers, France
| | - Vlad Ratziu
- Sorbonne Université, Institute of Cardiometabolism and Nutrition, Pitié-Salpêtrière Hospital, Paris, France
| | - Mathilde Wagner
- Radiology department, AP-HP.6, GH Pitié Salpêtrière - Charles Foix Sorbonne Université, Paris, France
| | - Salvatore Petta
- Section of Gastroenterology, PROMISE, University of Palermo, Italy
| | - Michela Antonucci
- Section of Radiology - Di.Bi.Me.F., University of Palermo, Palermo, Italy
| | - Elisabetta Bugianesi
- Division of Gastroenterology, Department of Medical Sciences, University of Torino, Torino, Italy
| | - Riccardo Faletti
- Department of Diagnostic and Interventional Radiology, University of Turin, Turin, Italy
| | - Luca Miele
- Department of Translational Medicine and Surgery, Medical School, Università Cattolica del S. Cuore and Fondazione Pol. Gemelli IRCCS Hospital, Rome, Italy
| | - Andreas Geier
- Department of Hepatology, University of Würzburg, Würzburg, Germany
| | - Jörn M Schattenberg
- Metabolic Liver Research Program, I. Department of Medicine, University Medical Centre, Mainz, Germany
| | - Emrich Tilman
- Department of Diagnostic and Interventional Radiology, University Medical Center of Johannes-Gutenberg-University, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Mattias Ekstedt
- Department of Health, Medicine and Caring Sciences, and Centre for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
| | - Peter Lundberg
- Department of Radiation Physics, and Centre for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
| | - Annalisa Berzigotti
- Department of Visceral Surgery and Medicine, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Adrian T Huber
- Department of Diagnostic, Interventional and Paediatric Radiology (DIPR), Bern University Hospital, University of Bern, Bern, Switzerland
| | - George Papatheodoridis
- Department of Gastroenterology, Medical School of National and Kapodistrian University of Athens, General Hospital of Athens "Laiko", Athens, Greece
| | - Hannele Yki-Järvinen
- Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Kimmo Porthan
- Department of Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | | | | | | | | | | | | | | | - Aldo Trylesinksi
- ADVANZPHARMA, Capital House, 1st Floor, 85 King William Street, London EC4N 7BL, United Kingdom
| | | | - Miljen Martic
- Novartis AG, Translational Medicine, Clinical and Precision Medicine Imaging, Basel, Switzerland
| | - Carla Yunis
- Clinical Development and Operations, Pfizer Inc., Lake Mary, FL, USA
| | - Theresa Tuthill
- Clinical Development and Operations, Pfizer Inc., Lake Mary, FL, USA
| | - Patrick M Bossuyt
- Department of Epidemiology & Data Science, Amsterdam Public Health, Amsterdam University Medical Centres, University of Amsterdam, the Netherlands
| | - Quentin M Anstee
- Translational & Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom; Newcastle NIHR Biomedical Research Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Oxford NIHR Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust and the University of Oxford, Oxford, UK
| | - Stephen Harrison
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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5
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Belsley G, Tyler DJ, Robson MD, Tunnicliffe EM. Optimal flip angles for in vivo liver 3D T 1 mapping and B 1+ mapping at 3T. Magn Reson Med 2023; 90:950-962. [PMID: 37125661 PMCID: PMC10952198 DOI: 10.1002/mrm.29683] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 04/01/2023] [Accepted: 04/10/2023] [Indexed: 05/02/2023]
Abstract
PURPOSE The spoiled gradient recalled echo (SPGR) sequence with variable flip angles (FAs) enables whole liverT 1 $$ {T}_1 $$ mapping at high spatial resolutions but is strongly affected byB 1 + $$ {B}_1^{+} $$ inhomogeneities. The aim of this work was to study how the precision of acquiredT 1 $$ {T}_1 $$ maps is affected by theT 1 $$ {T}_1 $$ andB 1 + $$ {B}_1^{+} $$ ranges observed in the liver at 3T, as well as how noise propagates from the acquired signals into the resultingT 1 $$ {T}_1 $$ map. THEORY TheT 1 $$ {T}_1 $$ variance was estimated through the Fisher information matrix with a total noise variance including, for the first time, theB 1 + $$ {B}_1^{+} $$ map noise as well as contributions from the SPGR noise. METHODS Simulations were used to find the optimal FAs for both theB 1 + $$ {B}_1^{+} $$ mapping andT 1 $$ {T}_1 $$ mapping. The simulations results were validated in 10 volunteers. RESULTS Four optimized SPGR FAs of 2°, 2°, 15°, and 15° (TR = 4.1 ms) andB 1 + $$ {B}_1^{+} $$ map FAs of 65° and 130° achieved aT 1 $$ {T}_1 $$ coefficient of variation of 6.2 ± 1.7% across 10 volunteers and validated our theoretical model. Four optimal FAs outperformed five uniformly spaced FAs, saving the patient one breath-hold. For the liverB 1 + $$ {B}_1^{+} $$ andT 1 $$ {T}_1 $$ parameter space at 3T, a higher return inT 1 $$ {T}_1 $$ precision was obtained by investing FAs in the SPGR acquisition rather than in theB 1 + $$ {B}_1^{+} $$ map. CONCLUSION A novel framework was developed and validated to calculate the SPGRT 1 $$ {T}_1 $$ variance. This framework efficiently identifies optimal FA values and determines the total number of SPGR andB 1 + $$ {B}_1^{+} $$ measurements needed to achieve a desiredT 1 $$ {T}_1 $$ precision.
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Affiliation(s)
- Gabriela Belsley
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Damian J. Tyler
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Matthew D. Robson
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
- PerspectumOxfordUK
| | - Elizabeth M. Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
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6
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Shanmuganathan M, Kotronias RA, Burrage MK, Ng Y, Banerjee A, Xie C, Fletcher A, Manley P, Borlotti A, Emfietzoglou M, Mentzer AJ, Marin F, Raman B, Tunnicliffe EM, Neubauer S, Piechnik SK, Channon KM, Ferreira VM. Acute changes in myocardial tissue characteristics during hospitalization in patients with COVID-19. Front Cardiovasc Med 2023; 10:1097974. [PMID: 36873410 PMCID: PMC9978174 DOI: 10.3389/fcvm.2023.1097974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 01/10/2023] [Indexed: 02/18/2023] Open
Abstract
Background Patients with a history of COVID-19 infection are reported to have cardiac abnormalities on cardiovascular magnetic resonance (CMR) during convalescence. However, it is unclear whether these abnormalities were present during the acute COVID-19 illness and how they may evolve over time. Methods We prospectively recruited unvaccinated patients hospitalized with acute COVID-19 (n = 23), and compared them with matched outpatient controls without COVID-19 (n = 19) between May 2020 and May 2021. Only those without a past history of cardiac disease were recruited. We performed in-hospital CMR at a median of 3 days (IQR 1-7 days) after admission, and assessed cardiac function, edema and necrosis/fibrosis, using left and right ventricular ejection fraction (LVEF, RVEF), T1-mapping, T2 signal intensity ratio (T2SI), late gadolinium enhancement (LGE) and extracellular volume (ECV). Acute COVID-19 patients were invited for follow-up CMR and blood tests at 6 months. Results The two cohorts were well matched in baseline clinical characteristics. Both had normal LVEF (62 ± 7 vs. 65 ± 6%), RVEF (60 ± 6 vs. 58 ± 6%), ECV (31 ± 3 vs. 31 ± 4%), and similar frequency of LGE abnormalities (16 vs. 14%; all p > 0.05). However, measures of acute myocardial edema (T1 and T2SI) were significantly higher in patients with acute COVID-19 when compared to controls (T1 = 1,217 ± 41 ms vs. 1,183 ± 22 ms; p = 0.002; T2SI = 1.48 ± 0.36 vs. 1.13 ± 0.09; p < 0.001). All COVID-19 patients who returned for follow up (n = 12) at 6 months had normal biventricular function, T1 and T2SI. Conclusion Unvaccinated patients hospitalized for acute COVID-19 demonstrated CMR imaging evidence of acute myocardial edema, which normalized at 6 months, while biventricular function and scar burden were similar when compared to controls. Acute COVID-19 appears to induce acute myocardial edema in some patients, which resolves in convalescence, without significant impact on biventricular structure and function in the acute and short-term. Further studies with larger numbers are needed to confirm these findings.
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Affiliation(s)
- Mayooran Shanmuganathan
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Rafail A. Kotronias
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Matthew K. Burrage
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
| | - Yujun Ng
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Abhirup Banerjee
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Cheng Xie
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Alison Fletcher
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Peter Manley
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Alessandra Borlotti
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Maria Emfietzoglou
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Alexander J. Mentzer
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
- Wellcome Center for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Federico Marin
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Betty Raman
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
| | | | - Elizabeth M. Tunnicliffe
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
| | - Stefan Neubauer
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Stefan K. Piechnik
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
| | - Keith M. Channon
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
| | - Vanessa M. Ferreira
- Acute Vascular Imaging Center (AVIC), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Oxford Center for Clinical Magnetic Resonance Research (OCMR), John Radcliffe Hospital, Oxford, United Kingdom
- Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, United Kingdom
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7
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Teh I, Romero R. WA, Boyle J, Coll‐Font J, Dall'Armellina E, Ennis DB, Ferreira PF, Kalra P, Kolipaka A, Kozerke S, Lohr D, Mongeon F, Moulin K, Nguyen C, Nielles‐Vallespin S, Raterman B, Schreiber LM, Scott AD, Sosnovik DE, Stoeck CT, Tous C, Tunnicliffe EM, Weng AM, Croisille P, Viallon M, Schneider JE. Validation of cardiac diffusion tensor imaging sequences: A multicentre test-retest phantom study. NMR Biomed 2022; 35:e4685. [PMID: 34967060 PMCID: PMC9285553 DOI: 10.1002/nbm.4685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 11/19/2021] [Accepted: 12/24/2021] [Indexed: 05/23/2023]
Abstract
Cardiac diffusion tensor imaging (DTI) is an emerging technique for the in vivo characterisation of myocardial microstructure, and there is a growing need for its validation and standardisation. We sought to establish the accuracy, precision, repeatability and reproducibility of state-of-the-art pulse sequences for cardiac DTI among 10 centres internationally. Phantoms comprising 0%-20% polyvinylpyrrolidone (PVP) were scanned with DTI using a product pulsed gradient spin echo (PGSE; N = 10 sites) sequence, and a custom motion-compensated spin echo (SE; N = 5) or stimulated echo acquisition mode (STEAM; N = 5) sequence suitable for cardiac DTI in vivo. A second identical scan was performed 1-9 days later, and the data were analysed centrally. The average mean diffusivities (MDs) in 0% PVP were (1.124, 1.130, 1.113) x 10-3 mm2 /s for PGSE, SE and STEAM, respectively, and accurate to within 1.5% of reference data from the literature. The coefficients of variation in MDs across sites were 2.6%, 3.1% and 2.1% for PGSE, SE and STEAM, respectively, and were similar to previous studies using only PGSE. Reproducibility in MD was excellent, with mean differences in PGSE, SE and STEAM of (0.3 ± 2.3, 0.24 ± 0.95, 0.52 ± 0.58) x 10-5 mm2 /s (mean ± 1.96 SD). We show that custom sequences for cardiac DTI provide accurate, precise, repeatable and reproducible measurements. Further work in anisotropic and/or deforming phantoms is warranted.
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Affiliation(s)
- Irvin Teh
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - William A. Romero R.
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Jordan Boyle
- School of Mechanical EngineeringUniversity of LeedsLeedsUK
| | - Jaume Coll‐Font
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Erica Dall'Armellina
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Daniel B. Ennis
- Division of RadiologyVA Palo Alto Health Care SystemPalo AltoCaliforniaUSA
- Department of RadiologyStanford UniversityStanfordCaliforniaUSA
| | - Pedro F. Ferreira
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - Prateek Kalra
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Arunark Kolipaka
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Sebastian Kozerke
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - David Lohr
- Department of Cardiovascular ImagingComprehensive Heart Failure CenterWürzburgGermany
| | | | - Kévin Moulin
- Department of RadiologyStanford UniversityStanfordCaliforniaUSA
| | - Christopher Nguyen
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Sonia Nielles‐Vallespin
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - Brian Raterman
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Laura M. Schreiber
- Department of Cardiovascular ImagingComprehensive Heart Failure CenterWürzburgGermany
| | - Andrew D. Scott
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - David E. Sosnovik
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Christian T. Stoeck
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - Cyril Tous
- Department of Radiology, Radiation‐Oncology and Nuclear Medicine and Institute of Biomedical EngineeringUniversité de MontréalMontréalCanada
| | - Elizabeth M. Tunnicliffe
- Radcliffe Department of MedicineUniversity of OxfordOxfordUK
- Oxford NIHR Biomedical Research CentreOxfordUK
| | - Andreas M. Weng
- Department of Diagnostic and Interventional RadiologyUniversity Hospital WürzburgWürzburgGermany
| | - Pierre Croisille
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Magalie Viallon
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Jürgen E. Schneider
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
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8
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Kitt J, Frost A, Mollison J, Tucker KL, Suriano K, Kenworthy Y, McCourt A, Woodward W, Tan C, Lapidaire W, Mills R, Lacharie M, Tunnicliffe EM, Raman B, Santos M, Roman C, Hanssen H, Mackillop L, Cairns A, Thilaganathan B, Chappell L, Aye C, Lewandowski AJ, McManus RJ, Leeson P. Postpartum blood pressure self-management following hypertensive pregnancy: protocol of the Physician Optimised Post-partum Hypertension Treatment (POP-HT) trial. BMJ Open 2022; 12:e051180. [PMID: 35197335 PMCID: PMC8867381 DOI: 10.1136/bmjopen-2021-051180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 01/25/2022] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION New-onset hypertension affects approximately 10% of pregnancies and is associated with a significant increase in risk of cardiovascular disease in later life, with blood pressure measured 6 weeks postpartum predictive of blood pressure 5-10 years later. A pilot trial has demonstrated that improved blood pressure control, achevied via self-management during the puerperium, was associated with lower blood pressure 3-4 years postpartum. Physician Optimised Post-partum Hypertension Treatment (POP-HT) will formally evaluate whether improved blood pressure control in the puerperium results in lower blood pressure at 6 months post partum, and improvements in cardiovascular and cerebrovascular phenotypes. METHODS AND ANALYSIS POP-HT is an open-label, parallel arm, randomised controlled trial involving 200 women aged 18 years or over, with a diagnosis of pre-eclampsia or gestational hypertension, and requiring antihypertensive medication at discharge. Women are recruited by open recruitment and direct invitation around time of delivery and randomised 1:1 to, either an intervention comprising physician-optimised self-management of postpartum blood pressure or, usual care. Women in the intervention group upload blood pressure readings to a 'smartphone' app that provides algorithm-driven individualised medication-titration. Medication changes are approved by physicians, who review blood pressure readings remotely. Women in the control arm follow assessment and medication adjustment by their usual healthcare team. The primary outcome is 24-hour average ambulatory diastolic blood pressure at 6-9 months post partum. Secondary outcomes include: additional blood pressure parameters at baseline, week 1 and week 6; multimodal cardiovascular assessments (CMR and echocardiography); parameters derived from multiorgan MRI including brain and kidneys; peripheral macrovascular and microvascular measures; angiogenic profile measures taken from blood samples and levels of endothelial circulating and cellular biomarkers; and objective physical activity monitoring and exercise assessment. An additional 20 women will be recruited after a normotensive pregnancy as a comparator group for endothelial cellular biomarkers. ETHICS AND DISSEMINATION IRAS PROJECT ID 273353. This trial has received a favourable opinion from the London-Surrey Research Ethics Committee and HRA (REC Reference 19/LO/1901). The investigator will ensure that this trial is conducted in accordance with the principles of the Declaration of Helsinki and follow good clinical practice guidelines. The investigators will be involved in reviewing drafts of the manuscripts, abstracts, press releases and any other publications arising from the study. Authors will acknowledge that the study was funded by the British Heart Foundation Clinical Research Training Fellowship (BHF Grant number FS/19/7/34148). Authorship will be determined in accordance with the ICMJE guidelines and other contributors will be acknowledged. TRIAL REGISTRATION NUMBER NCT04273854.
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Affiliation(s)
- Jamie Kitt
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Annabelle Frost
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Jill Mollison
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | | | - Katie Suriano
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Yvonne Kenworthy
- Oxford Cardiovascular Clinical Research Facility, University of Oxford, Oxford, UK
| | - Annabelle McCourt
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - William Woodward
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Cheryl Tan
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Winok Lapidaire
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - Rebecca Mills
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Miriam Lacharie
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Betty Raman
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Mauro Santos
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Cristian Roman
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Henner Hanssen
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Lucy Mackillop
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | - Alexandra Cairns
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | | | - Lucy Chappell
- Women's Health Academic Centre, King's College London, London, UK
| | - Christina Aye
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | - Adam J Lewandowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Richard J McManus
- Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Paul Leeson
- Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
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9
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Raman B, Tunnicliffe EM, Chan K, Ariga R, Hundertmark M, Ohuma EO, Sivalokanathan S, Tan YJG, Mahmod M, Hess AT, Karamitsos TD, Selvanayagam J, Jerosch-Herold M, Watkins H, Neubauer S. Association Between Sarcomeric Variants in Hypertrophic Cardiomyopathy and Myocardial Oxygenation: Insights From a Novel Oxygen-Sensitive Cardiovascular Magnetic Resonance Approach. Circulation 2021; 144:1656-1658. [PMID: 34780254 DOI: 10.1161/circulationaha.121.054015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Elizabeth M Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Kenneth Chan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Moritz Hundertmark
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Eric O Ohuma
- Maternal, Adolescent, Reproductive, & Child Health Centre, London School of Hygiene & Tropical Medicine, UK (E.O.O.)
| | - Sanjay Sivalokanathan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Yi Jie Gifford Tan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Aaron T Hess
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Theodoros D Karamitsos
- First Department of Cardiology, Aristotle University of Thessaloniki, AHEPA Hospital, Greece (T.D.K.)
| | - Joseph Selvanayagam
- Department of Cardiovascular Medicine, Flinders Medical Centre, Bedford Park, Adelaide, Australia (J.S.)
| | | | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford University Hospitals NHS Foundation Trust, UK (B.R., E.M.T., K.C., R.A., M.H., S.S., Y.J.G.T., M.M., A.T.H., H.W., S.N.)
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10
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Cassar MP, Tunnicliffe EM, Petousi N, Lewandowski AJ, Xie C, Mahmod M, Samat AHA, Evans RA, Brightling CE, Ho LP, Piechnik SK, Talbot NP, Holdsworth D, Ferreira VM, Neubauer S, Raman B. Symptom Persistence Despite Improvement in Cardiopulmonary Health - Insights from longitudinal CMR, CPET and lung function testing post-COVID-19. EClinicalMedicine 2021; 41:101159. [PMID: 34693230 PMCID: PMC8527025 DOI: 10.1016/j.eclinm.2021.101159] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The longitudinal trajectories of cardiopulmonary abnormalities and symptoms following infection with coronavirus disease (COVID-19) are unclear. We sought to describe their natural history in previously hospitalised patients, compare this with controls, and assess the relationship between symptoms and cardiopulmonary impairment at 6 months post-COVID-19. METHODS Fifty-eight patients and thirty matched controls (single visit), recruited between 14th March - 25th May 2020, underwent symptom-questionnaires, cardiac and lung magnetic resonance imaging (CMR), cardiopulmonary exercise test (CPET), and spirometry at 3 months following COVID-19. Of them, forty-six patients returned for follow-up assessments at 6 months. FINDINGS At 2-3 months, 83% of patients had at least one cardiopulmonary symptom versus 33% of controls. Patients and controls had comparable biventricular volumes and function. Native cardiac T1 (marker of fibroinflammation) and late gadolinium enhancement (LGE, marker of focal fibrosis) were increased in patients at 2-3 months. Sixty percent of patients had lung parenchymal abnormalities on CMR and 55% had reduced peak oxygen consumption (pV̇O2) on CPET. By 6 months, 52% of patients remained symptomatic. On CMR, indexed right ventricular (RV) end-diastolic volume (-4·3 mls/m2, P=0·005) decreased and RV ejection fraction (+3·2%, P=0·0003) increased. Native T1 and LGE improved and was comparable to controls. Lung parenchymal abnormalities and peak V̇O2, although better, were abnormal in patients versus controls. 31% had reduced pV̇O2 secondary to symptomatic limitation and muscular impairment. Cardiopulmonary symptoms in patients did not associate with CMR, lung function, or CPET measures. INTERPRETATION In patients, cardiopulmonary abnormalities improve over time, though some measures remain abnormal relative to controls. Persistent symptoms at 6 months post-COVID-19 did not associate with objective measures of cardiopulmonary health. FUNDING The authors' work was supported by the NIHR Oxford Biomedical Research Centre, Oxford British Heart Foundation (BHF) Centre of Research Excellence (RE/18/3/34214), United Kingdom Research Innovation and Wellcome Trust. This project is part of a tier 3 study (C-MORE) within the collaborative research programme entitled PHOSP-COVID Post-hospitalization COVID-19 study: a national consortium to understand and improve long-term health outcomes, funded by the Medical Research Council and Department of Health and Social Care/National Institute for Health Research Grant (MR/V027859/1) ISRCTN number 10980107.
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Affiliation(s)
- Mark Philip Cassar
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Elizabeth M. Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Nayia Petousi
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Department of Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Adam J. Lewandowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Cheng Xie
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
- Department of Radiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Azlan Helmy Abd Samat
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Rachael A. Evans
- NIHR Biomedical Research Centre (Respiratory theme), University Hospitals of Leicester NHS Trust, Leicester, UK
- Department of Respiratory Science, University of Leicester, Leicester, UK
| | - Christopher E. Brightling
- NIHR Biomedical Research Centre (Respiratory theme), University Hospitals of Leicester NHS Trust, Leicester, UK
- Department of Respiratory Science, University of Leicester, Leicester, UK
| | - Ling-Pei Ho
- Department of Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Weatherall Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan K. Piechnik
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Nick P. Talbot
- Department of Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - David Holdsworth
- Department of Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Vanessa M. Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
- Corresponding Author: Dr Betty Raman, Oxford Centre for Clinical Magnetic Resonance Research, Level 0, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, United Kingdom, Telephone number: 00441865234580
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Griffanti L, Raman B, Alfaro-Almagro F, Filippini N, Cassar MP, Sheerin F, Okell TW, Kennedy McConnell FA, Chappell MA, Wang C, Arthofer C, Lange FJ, Andersson J, Mackay CE, Tunnicliffe EM, Rowland M, Neubauer S, Miller KL, Jezzard P, Smith SM. Adapting the UK Biobank Brain Imaging Protocol and Analysis Pipeline for the C-MORE Multi-Organ Study of COVID-19 Survivors. Front Neurol 2021; 12:753284. [PMID: 34777224 PMCID: PMC8586081 DOI: 10.3389/fneur.2021.753284] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/06/2021] [Indexed: 01/08/2023] Open
Abstract
SARS-CoV-2 infection has been shown to damage multiple organs, including the brain. Multiorgan MRI can provide further insight on the repercussions of COVID-19 on organ health but requires a balance between richness and quality of data acquisition and total scan duration. We adapted the UK Biobank brain MRI protocol to produce high-quality images while being suitable as part of a post-COVID-19 multiorgan MRI exam. The analysis pipeline, also adapted from UK Biobank, includes new imaging-derived phenotypes (IDPs) designed to assess the possible effects of COVID-19. A first application of the protocol and pipeline was performed in 51 COVID-19 patients post-hospital discharge and 25 controls participating in the Oxford C-MORE study. The protocol acquires high resolution T1, T2-FLAIR, diffusion weighted images, susceptibility weighted images, and arterial spin labelling data in 17 min. The automated imaging pipeline derives 1,575 IDPs, assessing brain anatomy (including olfactory bulb volume and intensity) and tissue perfusion, hyperintensities, diffusivity, and susceptibility. In the C-MORE data, IDPs related to atrophy, small vessel disease and olfactory bulbs were consistent with clinical radiology reports. Our exploratory analysis tentatively revealed some group differences between recovered COVID-19 patients and controls, across severity groups, but not across anosmia groups. Follow-up imaging in the C-MORE study is currently ongoing, and this protocol is now being used in other large-scale studies. The protocol, pipeline code and data are openly available and will further contribute to the understanding of the medium to long-term effects of COVID-19.
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Affiliation(s)
- Ludovica Griffanti
- Department of Psychiatry, Wellcome Centre for Integrative Neuroimaging, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford Biomedical Research Centre (BRC) National Institute for Health Research (NIHR), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Fidel Alfaro-Almagro
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Nicola Filippini
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Camillo Hospital, Venice, Italy
| | - Mark Philip Cassar
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford Biomedical Research Centre (BRC) National Institute for Health Research (NIHR), University of Oxford, Oxford, United Kingdom
| | - Fintan Sheerin
- Department of Radiology, Oxford University Hospitals National Health Service (NHS) Foundation Trust, Oxford, United Kingdom
| | - Thomas W. Okell
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Flora A. Kennedy McConnell
- Mental Health & Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Nottingham Biomedical Research Centre, Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Michael A. Chappell
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
- Mental Health & Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, United Kingdom
- Nottingham Biomedical Research Centre, Queens Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Chaoyue Wang
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Christoph Arthofer
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Frederik J. Lange
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Jesper Andersson
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Clare E. Mackay
- Department of Psychiatry, Wellcome Centre for Integrative Neuroimaging, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Elizabeth M. Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford Biomedical Research Centre (BRC) National Institute for Health Research (NIHR), University of Oxford, Oxford, United Kingdom
| | - Matthew Rowland
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford Biomedical Research Centre (BRC) National Institute for Health Research (NIHR), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Karla L. Miller
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Peter Jezzard
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
| | - Stephen M. Smith
- Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), University of Oxford, Oxford, United Kingdom
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Cassar MP, Lewandowski AJ, Mahmod M, Xie C, Tunnicliffe EM, Petousi N, Talbot NP, Holdsworth D, Neubauer S, Raman B. Longitudinal trajectory of cardiac magnetic resonance and cardiopulmonary exercise testing findings in moderate to severe COVID-19 and association with symptoms. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.0238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Cardiac magnetic resonance (CMR) and cardiopulmonary exercise testing (CPET) have provided important insights into the prevalence of early cardiopulmonary abnormalities in COVID-19 patients. It is currently unknown whether such abnormalities persist over time and relate to ongoing symptoms.
Purpose
To describe the longitudinal trajectory of cardiopulmonary abnormalities on CMR and CPET in moderate to severe COVID-19 patients and assess their relationship with ongoing symptoms.
Methods
Fifty-eight previously hospitalised COVID-19 patients and 30 age, sex, body mass index, comorbidity-matched controls underwent CMR, CPET and a symptom-based questionnaire at 2–3 months (2–3m). Repeat assessments (including gas transfer) were performed in 46 patients at 6 months (6m).
Results
During admission, 1/3rd of patients needed ventilation or intensive care (Table 1) and three (5%) had a raised troponin.
On CMR, patients had preserved left (LV) and right ventricular (RV) volumes and function at 2–3m from infection. By 6m, LV function did not change but RV end diastolic volume decreased (mean difference −4.3 mls/m2, p=0.005) and RV function increased (mean difference +3.2%, p<0.001, Fig. 1A).
Patients had higher native T1 (a marker of fibroinflammation) at 2–3m compared to controls (Table 1, Fig. 1B), which normalised by 6m. Extracellular volume was normal and improved by 6m. Native T2, a marker of myocardial oedema, did not differ between patients and controls on serial CMR. At 2–3m, late gadolinium enhancement (LGE) was higher in patients (p=0.023) but became comparable to controls by 6m (p=0.62). Six (12%) patients had LGE in a myocarditis pattern and one (2%) had myocardial infarction. None had active myocarditis using the Modified Lake Louise Criteria.
Lung imaging (T2-weighted) revealed parenchymal abnormalities in 2/3rds of patients at 2–3 and 6 months. The extent of abnormalities improved on serial imaging (Table 1). Gas transfer (DLco) was worse in those with lung abnormalities (77% vs 91% of predicted, p=0.009).
CPET revealed reduced peak oxygen consumption (pVO2) in patients at 2–3m, which normalised by 6m (80.5% to 93.3% of predicted, p=0.001) (Table 1, Fig. 1C). At 2–3m, 49% of patients had submaximal tests (respiratory exchange ratio <1.1), reducing to 25% by 6m (p=0.057). VE/VCO2 slope, a marker of lung efficiency, was abnormal in patients but improved on serial CPET (Table 1, Fig. 1D).
Cardiac symptoms (chest pain, dyspnoea, palpitations, dizziness or syncope) were present in 83% of patients at 2–3m, reducing to 52% by 6m (p<0.001). There was no significant association between CMR or CPET parameters and persistent cardiac symptoms at 6m (Fig. 1E).
Conclusions
Cardiopulmonary parameters (on CMR and CPET) improved in moderate-severe COVID-19 patients from 2–3 to 6 months post infection. Despite this, patients continued to experience cardiac symptoms which had no relationship with measured parameters.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): 1. NIHR Oxford and Oxford Health Biomedical Research Centre, Oxford British Heart Foundation (BHF) Centre of Research Excellence (RE/18/3/34214), United Kingdom Research Innovation and Wellcome Trust2. Medical Research Council and Department of Health and Social Care/National Institute for Health Research Grant (MR/V027859/1) ISRCTN number 10980107 Table 1Figure 1
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Affiliation(s)
- M P Cassar
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - A J Lewandowski
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - M Mahmod
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - C Xie
- University of Oxford, Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford, United Kingdom
| | - E M Tunnicliffe
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - N Petousi
- University of Oxford, Nuffield Department of Medicine, Oxford, United Kingdom
| | - N P Talbot
- University of Oxford, Department of Physiology, Anatomy and Genetics, Oxford, United Kingdom
| | - D Holdsworth
- University of Oxford, Department of Physiology, Anatomy and Genetics, Oxford, United Kingdom
| | - S Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - B Raman
- University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
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13
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Mózes FE, Valkovič L, Pavlides M, Robson MD, Tunnicliffe EM. Hydration and glycogen affect T 1 relaxation times of liver tissue. NMR Biomed 2021; 34:e4530. [PMID: 33951228 DOI: 10.1002/nbm.4530] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 04/05/2021] [Indexed: 06/12/2023]
Abstract
T1 mapping is a useful tool for the assessment of patients with nonalcoholic fatty liver disease but still suffers from a large unexplained variance in healthy subjects. This study aims to characterize the potential effects of liver glycogen concentration and body hydration status on liver shortened modified Look-Locker inversion recovery (shMOLLI) T1 measurements. Eleven glycogen phantoms and 12 healthy volunteers (mean age: 31 years, three females) were scanned at 3 T using inversion recovery spin echo, multiple contrast spin echo (in phantoms), shMOLLI T1 mapping, multiple-echo spoiled gradient recalled echo and 13 C spectroscopy (in healthy volunteers). Phantom r1 and r2 relaxivities were determined from measured T1 and T2 values. Participants underwent a series of five metabolic experiments to vary their glycogen concentration and hydration levels: feeding, food fasting, exercising, underhydration, and rehydration. Descriptive statistics were calculated for shMOLLI T1 , inferior vena cava to aorta cross-sectional area ratio (IVC/Ao) as a marker of body hydration status, glycogen concentration, T2 * and proton density fat fraction values. A linear mixed model for shMOLLI R1 was constructed to determine the effects of glycogen concentration and IVC/Ao ratio. The mean shMOLLI T1 after fasting was 737 ± 67 ms. The mean within-subject change was 80 ± 45 ms. The linear mixed model revealed a glycogen r1 relaxivity in volunteers (0.18 M-1 s-1 , p = 0.03) close to that determined in phantoms (0.28 M-1 s-1 ). A unit change in IVC/Ao ratio was associated with a drop of -0.113 s-1 in R1 (p < 0.001). This study demonstrated a dependence of liver shMOLLI T1 values on liver glycogen concentration and overall body hydration status. Interparticipant variation of hydration status should be minimized in future liver MRI studies. Additionally, caution is advised when interpreting liver T1 measurements in participants with excess liver glycogen.
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Affiliation(s)
- Ferenc E Mózes
- The Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
| | - Ladislav Valkovič
- The Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
- Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Michael Pavlides
- The Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, University of Oxford and Oxford Radcliffe Hospitals NHS Trust, Oxford, UK
| | - Matthew D Robson
- The Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
- Perspectum, Gemini One, Oxford, UK
| | - Elizabeth M Tunnicliffe
- The Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, University of Oxford and Oxford Radcliffe Hospitals NHS Trust, Oxford, UK
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Jayaswal ANA, Levick C, Collier J, Tunnicliffe EM, Kelly MD, Neubauer S, Barnes E, Pavlides M. Liver cT 1 decreases following direct-acting antiviral therapy in patients with chronic hepatitis C virus. Abdom Radiol (NY) 2021; 46:1947-1957. [PMID: 33247768 PMCID: PMC8131342 DOI: 10.1007/s00261-020-02860-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/04/2020] [Accepted: 11/07/2020] [Indexed: 02/07/2023]
Abstract
PURPOSE Direct-acting antiviral therapies (DAAs) for treatment of chronic hepatitis C virus (HCV) have excellent rates of viral eradication, but their effect on regression of liver fibrosis is unclear. The primary aim was to use magnetic resonance imaging (MRI) and spectroscopy (MRS) to evaluate changes in liver fibrosis, liver fat and liver iron content (LIC) in patients with chronic HCV following treatment with DAAs. METHODS In this prospective study, 15 patients with chronic HCV due to start treatment with DAAs and with transient elastography (TE) > 8 kPa were recruited consecutively. Patients underwent MRI and MRS at baseline (before treatment), and at 24 weeks and 48 weeks after the end of treatment (EoT) for the measurement of liver cT1 (fibroinflammation), liver fat and T2* (LIC). RESULTS All patients achieved a sustained virological response. Liver cT1 showed significant decreases from baseline to 24 weeks post EoT (876 vs 806 ms, p = 0.002, n = 15), baseline to 48 weeks post EoT (876 vs 788 ms, p = 0.0002, n = 13) and 24 weeks post EoT to 48 weeks post EoT (806 vs 788 ms, p = 0.016, n = 13). Between baseline and 48 weeks EoT significant reduction in liver fat (5.17% vs 2.65%, p = 0.027) and an increase in reported LIC (0.913 vs 0.950 mg/g, p = 0.021) was observed. CONCLUSION Liver cT1 decreases in patients with chronic HCV undergoing successful DAA treatment. The relatively fast reduction in cT1 suggests a reduction in inflammation rather than regression of fibrosis.
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Affiliation(s)
- Arjun N A Jayaswal
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Christina Levick
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Jane Collier
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Oxford, UK
| | | | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Oxford, UK
| | - Eleanor Barnes
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Oxford, UK
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Michael Pavlides
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK.
- Oxford NIHR Biomedical Research Centre, Oxford, UK.
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Mózes FE, Tunnicliffe EM. Differences between T1 and corrected T1 cannot be attributed to iron-correction only. Pediatr Radiol 2021; 51:499-500. [PMID: 33502540 DOI: 10.1007/s00247-020-04956-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/23/2020] [Accepted: 12/20/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Ferenc E Mózes
- Oxford Centre for Clinical Magnetic Resonance Research, RDM Cardiovascular Medicine, University of Oxford, Oxford, OX3 9DU, UK.
| | - Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, RDM Cardiovascular Medicine, University of Oxford, Oxford, OX3 9DU, UK
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Raman B, Cassar MP, Tunnicliffe EM, Filippini N, Griffanti L, Alfaro-Almagro F, Okell T, Sheerin F, Xie C, Mahmod M, Mózes FE, Lewandowski AJ, Ohuma EO, Holdsworth D, Lamlum H, Woodman MJ, Krasopoulos C, Mills R, McConnell FAK, Wang C, Arthofer C, Lange FJ, Andersson J, Jenkinson M, Antoniades C, Channon KM, Shanmuganathan M, Ferreira VM, Piechnik SK, Klenerman P, Brightling C, Talbot NP, Petousi N, Rahman NM, Ho LP, Saunders K, Geddes JR, Harrison PJ, Pattinson K, Rowland MJ, Angus BJ, Gleeson F, Pavlides M, Koychev I, Miller KL, Mackay C, Jezzard P, Smith SM, Neubauer S. Medium-term effects of SARS-CoV-2 infection on multiple vital organs, exercise capacity, cognition, quality of life and mental health, post-hospital discharge. EClinicalMedicine 2021; 31:100683. [PMID: 33490928 PMCID: PMC7808914 DOI: 10.1016/j.eclinm.2020.100683] [Citation(s) in RCA: 342] [Impact Index Per Article: 114.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/22/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The medium-term effects of Coronavirus disease (COVID-19) on organ health, exercise capacity, cognition, quality of life and mental health are poorly understood. METHODS Fifty-eight COVID-19 patients post-hospital discharge and 30 age, sex, body mass index comorbidity-matched controls were enrolled for multiorgan (brain, lungs, heart, liver and kidneys) magnetic resonance imaging (MRI), spirometry, six-minute walk test, cardiopulmonary exercise test (CPET), quality of life, cognitive and mental health assessments. FINDINGS At 2-3 months from disease-onset, 64% of patients experienced breathlessness and 55% reported fatigue. On MRI, abnormalities were seen in lungs (60%), heart (26%), liver (10%) and kidneys (29%). Patients exhibited changes in the thalamus, posterior thalamic radiations and sagittal stratum on brain MRI and demonstrated impaired cognitive performance, specifically in the executive and visuospatial domains. Exercise tolerance (maximal oxygen consumption and ventilatory efficiency on CPET) and six-minute walk distance were significantly reduced. The extent of extra-pulmonary MRI abnormalities and exercise intolerance correlated with serum markers of inflammation and acute illness severity. Patients had a higher burden of self-reported symptoms of depression and experienced significant impairment in all domains of quality of life compared to controls (p<0.0001 to 0.044). INTERPRETATION A significant proportion of patients discharged from hospital reported symptoms of breathlessness, fatigue, depression and had limited exercise capacity. Persistent lung and extra-pulmonary organ MRI findings are common in patients and linked to inflammation and severity of acute illness. FUNDING NIHR Oxford and Oxford Health Biomedical Research Centres, British Heart Foundation Centre for Research Excellence, UKRI, Wellcome Trust, British Heart Foundation.
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Affiliation(s)
- Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Mark Philip Cassar
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Elizabeth M. Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Nicola Filippini
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for Human Brain Activity, Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Ludovica Griffanti
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for Human Brain Activity, Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Fidel Alfaro-Almagro
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Thomas Okell
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Fintan Sheerin
- Department of Radiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Cheng Xie
- Department of Radiology, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Ferenc E. Mózes
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, John Radcliffe Hospital Oxford, University of Oxford, Oxford, United Kingdom
| | - Adam J. Lewandowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Eric O. Ohuma
- Maternal, Adolescent, Reproductive & Child Health (MARCH) Centre, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
| | - David Holdsworth
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Hanan Lamlum
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Myles J. Woodman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Catherine Krasopoulos
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Rebecca Mills
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Flora A. Kennedy McConnell
- Division of Clinical Neuroscience, Faculty of Medicine & Health Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Chaoyue Wang
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Christoph Arthofer
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Frederik J. Lange
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Jesper Andersson
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Mark Jenkinson
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Charalambos Antoniades
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Keith M. Channon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Mayooran Shanmuganathan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Vanessa M. Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Stefan K. Piechnik
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
| | - Paul Klenerman
- Nuffield Department of Medicine, NIHR Oxford BRC, University of Oxford, Oxford, United Kingdom
| | - Christopher Brightling
- Institute for Lung Health, Department of Respiratory Sciences, NIHR Leicester BRC, University of Leicester, Leicester, United Kingdom
| | - Nick P. Talbot
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Nayia Petousi
- Nuffield Department of Medicine, NIHR Oxford BRC, University of Oxford, Oxford, United Kingdom
| | - Najib M. Rahman
- Nuffield Department of Medicine, NIHR Oxford BRC, University of Oxford, Oxford, United Kingdom
| | - Ling-Pei Ho
- Weatherall Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Kate Saunders
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - John R. Geddes
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Paul J. Harrison
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Kyle Pattinson
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom
| | - Matthew J. Rowland
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom
| | - Brian J. Angus
- Experimental Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Fergus Gleeson
- Department of Oncology, Medical Science Department, University of Oxford, Oxford, United Kingdom
| | - Michael Pavlides
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Translational Gastroenterology Unit, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ivan Koychev
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom
| | - Karla L. Miller
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Clare Mackay
- Wellcome Centre for Integrative Neuroimaging, Oxford Centre for Human Brain Activity, Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, United Kingdom
| | - Peter Jezzard
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Stephen M. Smith
- Wellcome Centre for Integrative Neuroimaging (WIN FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
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17
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Jayaswal ANA, Levick C, Selvaraj EA, Dennis A, Booth JC, Collier J, Cobbold J, Tunnicliffe EM, Kelly M, Barnes E, Neubauer S, Banerjee R, Pavlides M. Prognostic value of multiparametric magnetic resonance imaging, transient elastography and blood-based fibrosis markers in patients with chronic liver disease. Liver Int 2020; 40:3071-3082. [PMID: 32730664 DOI: 10.1111/liv.14625] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/03/2020] [Accepted: 07/22/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND & AIMS Liver cT1 , liver T1 , transient elastography (TE) and blood-based biomarkers have independently been shown to predict clinical outcomes but have not been directly compared in a single cohort of patients. Our aim was to compare these tests' prognostic value in a cohort of patients with compensated chronic liver disease. METHODS Patients with unselected compensated liver disease aetiologies had baseline assessments and were followed up for development of clinical outcomes, blinded to the imaging results. The prognostic value of non-invasive liver tests at prespecified thresholds was assessed for a combined clinical endpoint comprising ascites, variceal bleeding, hepatic encephalopathy, hepatocellular carcinoma, liver transplantation and mortality. RESULTS One hundred and ninety-seven patients (61% male) with median age of 54 years were followed up for 693 patient-years (median (IQR) 43 (26-58) months). The main diagnoses were NAFLD (41%), viral hepatitis (VH, 25%) and alcohol-related liver disease (ArLD; 14%). During follow-up 14 new clinical events, and 11 deaths occurred. Clinical outcomes were predicted by liver cT1 > 825ms with HR 9.9 (95% CI: 1.29-76.4, P = .007), TE > 8kPa with HR 7.8 (95% CI: 0.97-62.3, P = .02) and FIB-4 > 1.45 with HR 4.09 (95% CI: 0.90-18.4, P = .05). In analysis taking into account technical failure and unreliability, liver cT1 > 825 ms could predict clinical outcomes (P = .03), but TE > 8kPa could not (P = .4). CONCLUSIONS We provide further evidence that liver cT1 , TE and serum-based biomarkers can predict clinical outcomes, but when taking into account technical failure/unreliability, TE cut-offs perform worse than those of cT1 and blood biomarkers.
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Affiliation(s)
- Arjun N A Jayaswal
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Christina Levick
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Emmanuel A Selvaraj
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.,Translational Gastroenterology Unit, University of Oxford, Oxford, UK.,Oxford NIHR Biomedical Research Centre, Oxford, UK
| | | | | | - Jane Collier
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Jeremy Cobbold
- Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Eleanor Barnes
- Peter Medawar Building, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Michael Pavlides
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.,Translational Gastroenterology Unit, University of Oxford, Oxford, UK.,Oxford NIHR Biomedical Research Centre, Oxford, UK
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18
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Apps A, Valkovič L, Peterzan M, Lau JYC, Hundertmark M, Clarke W, Tunnicliffe EM, Ellis J, Tyler DJ, Neubauer S, Rider OJ, Rodgers CT, Schmid AI. Quantifying the effect of dobutamine stress on myocardial Pi and pH in healthy volunteers: A 31 P MRS study at 7T. Magn Reson Med 2020; 85:1147-1159. [PMID: 32929770 PMCID: PMC8239988 DOI: 10.1002/mrm.28494] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 07/07/2020] [Accepted: 08/03/2020] [Indexed: 12/15/2022]
Abstract
Purpose Phosphorus spectroscopy (31P‐MRS) is a proven method to probe cardiac energetics. Studies typically report the phosphocreatine (PCr) to adenosine triphosphate (ATP) ratio. We focus on another 31P signal: inorganic phosphate (Pi), whose chemical shift allows computation of myocardial pH, with Pi/PCr providing additional insight into cardiac energetics. Pi is often obscured by signals from blood 2,3‐diphosphoglycerate (2,3‐DPG). We introduce a method to quantify Pi in 14 min without hindrance from 2,3‐DPG. Methods Using a 31P stimulated echo acquisition mode (STEAM) sequence at 7 Tesla that inherently suppresses signal from 2,3‐DPG, the Pi peak was cleanly resolved. Resting state UTE‐chemical shift imaging (PCr/ATP) and STEAM 31P‐MRS (Pi/PCr, pH) were undertaken in 23 healthy controls; pH and Pi/PCr were subsequently recorded during dobutamine infusion. Results We achieved a clean Pi signal both at rest and stress with good 2,3‐DPG suppression. Repeatability coefficient (8 subjects) for Pi/PCr was 0.036 and 0.12 for pH. We report myocardial Pi/PCr and pH at rest and during catecholamine stress in healthy controls. Pi/PCr was maintained during stress (0.098 ± 0.031 [rest] vs. 0.098 ± 0.031 [stress] P = .95); similarly, pH did not change (7.09 ± 0.07 [rest] vs. 7.08 ± 0.11 [stress] P = .81). Feasibility for patient studies was subsequently successfully demonstrated in a patient with cardiomyopathy. Conclusion We introduced a method that can resolve Pi using 7 Tesla STEAM 31P‐MRS. We demonstrate the stability of Pi/PCr and myocardial pH in volunteers at rest and during catecholamine stress. This protocol is feasible in patients and potentially of use for studying pathological myocardial energetics.
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Affiliation(s)
- Andrew Apps
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ladislav Valkovič
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Mark Peterzan
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Justin Y C Lau
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Moritz Hundertmark
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - William Clarke
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jane Ellis
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Damian J Tyler
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Oliver J Rider
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Christopher T Rodgers
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom
| | - Albrecht Ingo Schmid
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.,High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
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19
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Ariga R, Tunnicliffe EM, Manohar SG, Mahmod M, Raman B, Piechnik SK, Francis JM, Robson MD, Neubauer S, Watkins H. Identification of Myocardial Disarray in Patients With Hypertrophic Cardiomyopathy and Ventricular Arrhythmias. J Am Coll Cardiol 2020; 73:2493-2502. [PMID: 31118142 PMCID: PMC6548973 DOI: 10.1016/j.jacc.2019.02.065] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 02/07/2019] [Accepted: 02/26/2019] [Indexed: 01/26/2023]
Abstract
Background Myocardial disarray is a likely focus for fatal arrhythmia in hypertrophic cardiomyopathy (HCM). This microstructural abnormality can be inferred by mapping the preferential diffusion of water along cardiac muscle fibers using diffusion tensor cardiac magnetic resonance (DT-CMR) imaging. Fractional anisotropy (FA) quantifies directionality of diffusion in 3 dimensions. The authors hypothesized that FA would be reduced in HCM due to disarray and fibrosis that may represent the anatomic substrate for ventricular arrhythmia. Objectives This study sought to assess FA as a noninvasive in vivo biomarker of HCM myoarchitecture and its association with ventricular arrhythmia. Methods A total of 50 HCM patients (47 ± 15 years of age, 77% male) and 30 healthy control subjects (46 ± 16 years of age, 70% male) underwent DT-CMR in diastole, cine, late gadolinium enhancement (LGE), and extracellular volume (ECV) imaging at 3-T. Results Diastolic FA was reduced in HCM compared with control subjects (0.49 ± 0.05 vs. 0.52 ± 0.03; p = 0.0005). Control subjects had a mid-wall ring of high FA. In HCM, this ring was disrupted by reduced FA, consistent with published histology demonstrating that disarray and fibrosis invade circumferentially aligned mid-wall myocytes. LGE and ECV were significant predictors of FA, in line with fibrosis contributing to low FA. Yet FA adjusted for LGE and ECV remained reduced in HCM (p = 0.028). FA in the hypertrophied segment was reduced in HCM patients with ventricular arrhythmia compared to patients without (n = 15; 0.41 ± 0.03 vs. 0.46 ± 0.06; p = 0.007). A decrease in FA of 0.05 increased odds of ventricular arrhythmia by 2.5 (95% confidence interval: 1.2 to 5.3; p = 0.015) in HCM and remained significant even after correcting for LGE, ECV, and wall thickness (p = 0.036). Conclusions DT-CMR assessment of left ventricular myoarchitecture matched patterns reported previously on histology. Low diastolic FA in HCM was associated with ventricular arrhythmia and is likely to represent disarray after accounting for fibrosis. The authors propose that diastolic FA could be the first in vivo marker of disarray in HCM and a potential independent risk factor.
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Affiliation(s)
- Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Elizabeth M Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sanjay G Manohar
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan K Piechnik
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jane M Francis
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matthew D Robson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.
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20
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Raman B, Chan K, Mahmod M, Ariga R, Sivalokanathan S, Karamitsos TD, Selvanayagam J, Hess AT, Tunnicliffe EM, Watkins H, Neubauer S. 2378Blunted stress myocardial oxygenation and not myocardial perfusion reserve is associated with arrhythmic risk in hypertrophic cardiomyopathy. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
In hypertrophic cardiomyopathy (HCM), myocardial ischaemia is believed to play a role in fatal life-threatening ventricular arrhythmias and caused by microvascular dysfunction manifesting as impaired myocardial perfusion. However, previous studies suggest that myocardial oxygenation during vasodilator stress may also be blunted when perfusion is normal, due to increased metabolic demands conferred by energy-costly sarcomeric mutations, left ventricular hypertrophy and outflow obstruction. Whether or not impaired myocardial perfusion reserve or blunted stress oxygenation on cardiac magnetic resonance (CMR) predict the risk of ventricular arrhythmia in HCM is unknown.
Purpose
We sought to investigate if impaired myocardial perfusion reserve or stress oxygenation is associated with an increased risk of ventricular arrhythmia in HCM.
Methods
103 genotyped HCM patients (mean age 47±15 years) and 32 age- and sex-matched healthy controls underwent adenosine stress blood oxygen level dependent (BOLD) imaging, first pass perfusion and late gadolinium imaging (LGE) on CMR to assess stress oxygenation (BOLD ΔSI), myocardial perfusion reserve index (MPRI), and fibrosis respectively. All HCM patients were monitored for ventricular tachycardia (≥3 beats, ≥120 beats per minute) on a 24-hour Holter.
Results
As expected, MPRI was significantly reduced in HCM (1.5±0.4 vs 2.0±0.3, p<0.0001) compared to controls. Stress oxygenation response was blunted in HCM versus controls (9.1±4.1% vs 17.0±1.6%, p<0.0001, Figure 1B). Twenty-six (25%) patients developed ventricular tachycardia on Holter monitoring. On univariate analysis, only stress oxygenation and not MPRI associated with ventricular tachycardia. The prevalence of ventricular tachycardia in HCM increased with decreasing quartiles of stress oxygenation (Figure 1D). HCM patients in the lowest quartile of oxygenation (BOLD ΔSI <6.5%) were at a three-fold risk of ventricular tachycardia (OR 3.04, 95% confidence interval 1.02–9.05, p=0.04) on multivariable analysis (after adjusting for sudden cardiac death risk factors and LGE mass) compared to other patients. Sarcomeric mutation status was an independent determinant of stress oxygenation on multivariable analysis. Stress oxygenation was impaired in phenotype-negative sarcomeric mutation carriers (Sarc+P-, n=16) despite normal perfusion (Figure 1C, E). Sarcomeric HCM (Sarc+HCM) had more severe impairment in stress oxygenation than genotype negative HCM (G-HCM) and controls (Figure 1E).
Figure 1
Conclusion
In HCM, blunted stress-induced oxygenation is associated with an increased risk of ventricular arrhythmia and may represent a novel biomarker of arrhythmic risk. Sarcomeric mutation status is an important determinant of stress oxygenation response.
Acknowledgement/Funding
National Institute for Health Research Oxford Biomedical Centre and British Heart Foundation.
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Affiliation(s)
- B Raman
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - K Chan
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - M Mahmod
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - R Ariga
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - S Sivalokanathan
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - T D Karamitsos
- Aristotle University of Thessaloniki, First Department of Cardiology, Thessaloniki, Greece
| | - J Selvanayagam
- Flinders Medical Centre and Flinders University, Adelaide, Australia
| | - A T Hess
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - E M Tunnicliffe
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - H Watkins
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - S Neubauer
- University of Oxford, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
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21
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Stoeck CT, Scott AD, Ferreira PF, Tunnicliffe EM, Teh I, Nielles-Vallespin S, Moulin K, Sosnovik DE, Viallon M, Croisille P, Kozerke S, Firmin DN, Ennis DB, Schneider JE. Motion-Induced Signal Loss in In Vivo Cardiac Diffusion-Weighted Imaging. J Magn Reson Imaging 2019; 51:319-320. [PMID: 31034705 DOI: 10.1002/jmri.26767] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/18/2019] [Accepted: 04/18/2019] [Indexed: 01/07/2023] Open
Abstract
LEVEL OF EVIDENCE 5 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:319-320.
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Affiliation(s)
- Christian T Stoeck
- Institute for Biomedical Engineering, University and ETH, Zurich, Switzerland
| | - Andrew D Scott
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Pedro F Ferreira
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Elizabeth M Tunnicliffe
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, Oxford, UK.,NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Irvin Teh
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
| | - Sonia Nielles-Vallespin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Kevin Moulin
- Department of Radiology, Stanford University, Stanford, California, USA
| | - David E Sosnovik
- Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Magalie Viallon
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France.,CREATIS UMR CNRS5220 INSERM U1206, University of Lyon, Lyon, France
| | - Pierre Croisille
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France.,CREATIS UMR CNRS5220 INSERM U1206, University of Lyon, Lyon, France
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH, Zurich, Switzerland
| | - David N Firmin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Daniel B Ennis
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Jurgen E Schneider
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK.,Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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22
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Mozes FE, Tunnicliffe EM, Moolla A, Marjot T, Levick CK, Pavlides M, Robson MD. Mapping tissue water T 1 in the liver using the MOLLI T 1 method in the presence of fat, iron and B 0 inhomogeneity. NMR Biomed 2019; 32:e4030. [PMID: 30462873 PMCID: PMC6492199 DOI: 10.1002/nbm.4030] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 09/11/2018] [Accepted: 09/20/2018] [Indexed: 05/11/2023]
Abstract
Modified Look-Locker inversion recovery (MOLLI) T1 mapping sequences can be useful in cardiac and liver tissue characterization, but determining underlying water T1 is confounded by iron, fat and frequency offsets. This article proposes an algorithm that provides an independent water MOLLI T1 (referred to as on-resonance water T1 ) that would have been measured if a subject had no fat and normal iron, and imaging had been done on resonance. Fifteen NiCl2 -doped agar phantoms with different peanut oil concentrations and 30 adults with various liver diseases, nineteen (63.3%) with liver steatosis, were scanned at 3 T using the shortened MOLLI (shMOLLI) T1 mapping, multiple-echo spoiled gradient-recalled echo and 1 H MR spectroscopy sequences. An algorithm based on Bloch equations was built in MATLAB, and water shMOLLI T1 values of both phantoms and human participants were determined. The quality of the algorithm's result was assessed by Pearson's correlation coefficient between shMOLLI T1 values and spectroscopically determined T1 values of the water, and by linear regression analysis. Correlation between shMOLLI and spectroscopy-based T1 values increased, from r = 0.910 (P < 0.001) to r = 0.998 (P < 0.001) in phantoms and from r = 0.493 (for iron-only correction; P = 0.005) to r = 0.771 (for iron, fat and off-resonance correction; P < 0.001) in patients. Linear regression analysis revealed that the determined water shMOLLI T1 values in patients were independent of fat and iron. It can be concluded that determination of on-resonance water (sh)MOLLI T1 independent of fat, iron and macroscopic field inhomogeneities was possible in phantoms and human subjects.
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Affiliation(s)
- Ferenc E. Mozes
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
| | - Elizabeth M. Tunnicliffe
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
| | - Ahmad Moolla
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM)University of Oxford, Churchill HospitalOxfordUK
| | - Thomas Marjot
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM)University of Oxford, Churchill HospitalOxfordUK
| | - Christina K. Levick
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
- Translational Gastroenterology UnitUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Michael Pavlides
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
- Translational Gastroenterology UnitUniversity of Oxford, John Radcliffe HospitalOxfordUK
- Oxford NIHR Biomedical Research CentreOxfordUK
| | - Matthew D. Robson
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe HospitalOxfordUK
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23
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Hess AT, Tunnicliffe EM, Rodgers CT, Robson MD. Diaphragm position can be accurately estimated from the scattering of a parallel transmit RF coil at 7 T. Magn Reson Med 2017; 79:2164-2169. [PMID: 28771792 PMCID: PMC5836958 DOI: 10.1002/mrm.26866] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/12/2017] [Accepted: 07/19/2017] [Indexed: 11/10/2022]
Abstract
Purpose To evaluate the use of radiofrequency scattering of a parallel transmit coil to track diaphragm motion. Methods Measurements made during radiofrequency excitation on an 8‐channel parallel transmit coil by the directional couplers of the radiofrequency safety monitor were combined and converted into diaphragm position. A 30‐s subject‐specific calibration with an MRI navigator was used to determine a diaphragm estimate from each directional‐coupler measure. Seven healthy volunteers were scanned at 7 T, in which images of the diaphragm were continuously acquired and directional couplers were monitored during excitation radiofrequency pulses. The ability to detect coughing was evaluated in one subject. The method was implemented on the scanner and evaluated for diaphragm gating of a free‐breathing cardiac cine. Results Six of the seven scans were successful. In these subjects, the root mean square difference between MRI and scattering estimation of the superior–inferior diaphragm position was 1.4 ± 0.5 mm. On the scanner, the position was calculated less than 2 ms after every radiofrequency pulse. A prospectively gated (echocardiogram and respiration) high‐resolution free‐breathing cine showed no respiratory artifact and sharp blood‐myocardium definition. Conclusions Transmit coil scattering is sensitive to diaphragm motion and provides rapid, quantitative, and accurate monitoring of respiration. Magn Reson Med 79:2164–2169, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
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Affiliation(s)
- Aaron T Hess
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - Elizabeth M Tunnicliffe
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - Christopher T Rodgers
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
| | - Matthew D Robson
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
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24
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Pavlides M, Banerjee R, Tunnicliffe EM, Kelly C, Collier J, Wang LM, Fleming KA, Cobbold JF, Robson MD, Neubauer S, Barnes E. Multiparametric magnetic resonance imaging for the assessment of non-alcoholic fatty liver disease severity. Liver Int 2017; 37:1065-1073. [PMID: 27778429 PMCID: PMC5518289 DOI: 10.1111/liv.13284] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 10/20/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS The diagnosis of non-alcoholic steatohepatitis and fibrosis staging are central to non-alcoholic fatty liver disease assessment. We evaluated multiparametric magnetic resonance in the assessment of non-alcoholic steatohepatitis and fibrosis using histology as standard in non-alcoholic fatty liver disease. METHODS Seventy-one patients with suspected non-alcoholic fatty liver disease were recruited within 1 month of liver biopsy. Magnetic resonance data were used to define the liver inflammation and fibrosis score (LIF 0-4). Biopsies were assessed for steatosis, lobular inflammation, ballooning and fibrosis and classified as non-alcoholic steatohepatitis or simple steatosis, and mild or significant (Activity ≥2 and/or Fibrosis ≥2 as defined by the Fatty Liver Inhibition of Progression consortium) non-alcoholic fatty liver disease. Transient elastography was also performed. RESULTS Magnetic resonance success rate was 95% vs 59% for transient elastography (P<.0001). Fibrosis stage on biopsy correlated with liver inflammation and fibrosis (rs =.51, P<.0001). The area under the receiver operating curve using liver inflammation and fibrosis for the diagnosis of cirrhosis was 0.85. Liver inflammation and fibrosis score for ballooning grades 0, 1 and 2 was 1.2, 2.7 and 3.5 respectively (P<.05) with an area under the receiver operating characteristic curve of 0.83 for the diagnosis of ballooning. Patients with steatosis had lower liver inflammation and fibrosis (1.3) compared to patients with non-alcoholic steatohepatitis (3.0) (P<.0001); area under the receiver operating characteristic curve for the diagnosis of non-alcoholic steatohepatitis was 0.80. Liver inflammation and fibrosis scores for patients with mild and significant non-alcoholic fatty liver disease were 1.2 and 2.9 respectively (P<.0001). The area under the receiver operating characteristic curve of liver inflammation and fibrosis for the diagnosis of significant non-alcoholic fatty liver disease was 0.89. CONCLUSIONS Multiparametric magnetic resonance is a promising technique with good diagnostic accuracy for non-alcoholic fatty liver disease histological parameters, and can potentially identify patients with non-alcoholic steatohepatitis and cirrhosis.
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Affiliation(s)
- Michael Pavlides
- Oxford Centre for Clinical Magnetic Resonance ResearchRadcliffe Department of MedicineUniversity of OxfordOxfordUK,Translational Gastroenterology UnitUniversity of OxfordOxfordUK,The Oxford NIHR Biomedical Research CentreOxfordUK
| | | | - Elizabeth M. Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance ResearchRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | | | - Jane Collier
- Translational Gastroenterology UnitUniversity of OxfordOxfordUK
| | - Lai Mun Wang
- Department of HistopathologyOxford University HospitalsOxfordUK
| | | | - Jeremy F. Cobbold
- Translational Gastroenterology UnitUniversity of OxfordOxfordUK,The Oxford NIHR Biomedical Research CentreOxfordUK
| | - Matthew D. Robson
- Oxford Centre for Clinical Magnetic Resonance ResearchRadcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance ResearchRadcliffe Department of MedicineUniversity of OxfordOxfordUK,The Oxford NIHR Biomedical Research CentreOxfordUK
| | - Eleanor Barnes
- Translational Gastroenterology UnitUniversity of OxfordOxfordUK,The Oxford NIHR Biomedical Research CentreOxfordUK,The Peter Medawar Building for Pathogen ResearchUniversity of OxfordOxfordUK
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25
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Tunnicliffe EM, Ferreira P, Scott AD, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin D. Intercentre reproducibility of second eigenvector orientation in cardiac diffusion tensor imaging. J Cardiovasc Magn Reson 2016. [PMCID: PMC5032190 DOI: 10.1186/1532-429x-18-s1-p35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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26
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Tunnicliffe EM, Banerjee R, Pavlides M, Neubauer S, Robson MD. A model for hepatic fibrosis: the competing effects of cell loss and iron on shortened modified Look-Locker inversion recovery T 1 (shMOLLI-T 1 ) in the liver. J Magn Reson Imaging 2016; 45:450-462. [PMID: 27448630 DOI: 10.1002/jmri.25392] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/05/2016] [Indexed: 12/15/2022] Open
Abstract
PURPOSE To propose a simple multicompartment model of the liver and use Bloch-McConnell simulations to demonstrate the effects of iron and fibrosis on shortened-MOLLI (shMOLLI) T1 measurements. Liver T1 values have shown sensitivity to inflammation and fibrosis, but are also affected by hepatic iron content. Modified Look-Locker inversion recovery (MOLLI) T1 measurements are biased by the lower T2 associated with high iron. MATERIALS AND METHODS A tissue model was generated consisting of liver cells and extracellular fluid (ECF), with iron-dependent relaxation rates. Fibrosis was imitated by increasing the ECF proportion. Simulations of the shMOLLI sequence produced a look-up table (LUT) of shMOLLI-T1 for a given ECF fraction and iron content. The LUT was used to calculate ECF(shMOLLI-T1 ), assuming normal hepatic iron content (HIC), and ECF(shMOLLI- T1,T2*), accounting for HIC determined by T2*, for 77 patients and compared to fibrosis assessed by liver biopsy. RESULTS Simulations showed that increasing HIC decreases shMOLLI-T1 , with an increase in HIC from 1.0 to 2.5 mg/g at normal ECF fraction decreasing shMOLLI-T1 by 160 msec, while increasing ECF increased ShMOLLI-T1 , with an increase of 20% ECF at normal iron increasing shMOLLI-T1 by 200 msec. Calculated patient ECF(shMOLLI-T1 ) showed a strong dependence on Ishak score (3.3 ± 0.8 %ECF/Ishak stage) and 1/T2* (-0.23 ± 0.04 %ECF/Hz). However, when iron was accounted for to produce ECF(shMOLLI- T1,T2*), it was independent of HIC but retained sensitivity to Ishak score. CONCLUSION Use of this multicompartment model of the liver with Bloch-McConnell simulation should enable compensation of iron effects when using shMOLLI-T1 to assess fibrosis. LEVEL OF EVIDENCE 1 J. Magn. Reson. Imaging 2017;45:450-462.
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Affiliation(s)
- Elizabeth M Tunnicliffe
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Rajarshi Banerjee
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Michael Pavlides
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK.,Translational Gastroenterology Unit, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Matthew D Robson
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
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27
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Mozes FE, Tunnicliffe EM, Pavlides M, Robson MD. Influence of fat on liver T1 measurements using modified Look-Locker inversion recovery (MOLLI) methods at 3T. J Magn Reson Imaging 2016; 44:105-11. [PMID: 26762615 PMCID: PMC4982078 DOI: 10.1002/jmri.25146] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Accepted: 12/21/2015] [Indexed: 01/23/2023] Open
Abstract
PURPOSE To characterize the effect of fat on modified Look-Locker inversion recovery (MOLLI) T1 maps of the liver. The balanced steady-state free precession (bSSFP) sequence causes water and fat signals to have opposite phase when repetition time (TR) = 2.3 msec at 3T. In voxels that contain both fat and water, the MOLLI T1 measurement is influenced by the choice of TR. MATERIALS AND METHODS MOLLI T1 measurements of the liver were simulated using the Bloch equations while varying the hepatic lipid content (HLC). Phantom scans were performed on margarine phantoms, using both MOLLI and spin echo inversion recovery sequences. MOLLI T1 at 3T and HLC were determined in patients (n = 8) before and after bariatric surgery. RESULTS At 3T, with HLC in the 0-35% range, higher fat fraction values lead to longer MOLLI T1 values when TR = 2.3 msec. Patients were found to have higher MOLLI T1 at elevated HLC (T1 = 929 ± 97 msec) than at low HLC (T1 = 870 ± 44 msec). CONCLUSION At 3T, MOLLI T1 values are affected by HLC, substantially changing MOLLI T1 in a clinically relevant range of fat content. J. Magn. Reson. Imaging 2016;44:105-111.
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Affiliation(s)
- Ferenc E Mozes
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Elizabeth M Tunnicliffe
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Michael Pavlides
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, UK
- Translational Gastroenterology Unit, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Matthew D Robson
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, UK
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28
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Hess AT, Bissell MM, Ntusi NAB, Lewis AJM, Tunnicliffe EM, Greiser A, Stalder AF, Francis JM, Myerson SG, Neubauer S, Robson MD. Aortic 4D flow: quantification of signal-to-noise ratio as a function of field strength and contrast enhancement for 1.5T, 3T, and 7T. Magn Reson Med 2014; 73:1864-71. [PMID: 24934930 DOI: 10.1002/mrm.25317] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/28/2014] [Accepted: 05/22/2014] [Indexed: 01/10/2023]
Abstract
PURPOSE To investigate for the first time the feasibility of aortic four-dimensional (4D) flow at 7T, both contrast enhanced (CE) and non-CE. To quantify the signal-to-noise ratio (SNR) in aortic 4D flow as a function of field strength and CE with gadobenate dimeglumine (MultiHance). METHODS Six healthy male volunteers were scanned at 1.5T, 3T, and 7T with both non-CE and CE acquisitions. Temporal SNR was calculated. Flip angle optimization for CE 4D flow was carried out using Bloch simulations that were validated against in vivo measurements. RESULTS The 7T provided 2.2 times the SNR of 3T while 3T provided 1.7 times the SNR of 1.5T in non-CE acquisitions in the descending aorta. The SNR gains achieved by CE were 1.8-fold at 1.5T, 1.7-fold at 3T, and 1.4-fold at 7T, respectively. CONCLUSION The 7T provides a new tool to explore aortic 4D flow, yielding higher SNR that can be used to push the boundaries of acceleration and resolution. Field strength and contrast enhancement at all fields provide significant improvements in SNR.
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Affiliation(s)
- Aaron T Hess
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, United Kingdom
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29
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Tunnicliffe EM, Scott AD, Ferreira P, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin DN. Intercentre reproducibility of cardiac apparent diffusion coefficient and fractional anisotropy in healthy volunteers. J Cardiovasc Magn Reson 2014; 16:31. [PMID: 24886285 PMCID: PMC4028111 DOI: 10.1186/1532-429x-16-31] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 04/17/2014] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Diffusion tensor cardiac magnetic resonance (DT-CMR) enables probing of the microarchitecture of the myocardium, but the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) reported in healthy volunteers have been inconsistent. The aim of this study was to validate a stimulated-echo diffusion sequence using phantoms, and to assess the intercentre reproducibility of in-vivo diffusion measures using the sequence. METHODS AND RESULTS A stimulated-echo, cardiac-gated DT-CMR sequence with a reduced-field-of-view, single-shot EPI readout was used at two centres with 3 T MRI scanners. Four alkane phantoms with known diffusivities were scanned at a single centre using a stimulated echo sequence and a spin-echo Stejskal-Tanner diffusion sequence. The median (maximum, minimum) difference between the DT-CMR sequence and Stejskal-Tanner sequence was 0.01 (0.04, 0.0006) × 10(-3) mm2/s (2%), and between the DT-CMR sequence and literature diffusivities was 0.02 (0.05, 0.006) × 10(-3) mm2/s (4%).The same ten healthy volunteers were scanned using the DT-CMR sequence at the two centres less than seven days apart. Average ADC and FA were calculated in a single mid-ventricular, short axis slice. Intercentre differences were tested for statistical significance at the p < 0.05 level using paired t-tests. The mean ADC ± standard deviation for all subjects averaged over both centres was 1.10 ± 0.06 × 10(-3) mm2/s in systole and 1.20 ± 0.09 × 10-3 mm2/s in diastole; FA was 0.41 ± 0.04 in systole and 0.54 ± 0.03 in diastole. With similarly-drawn regions-of-interest, systolic ADC (difference 0.05 × 10(-3) mm2/s), systolic FA (difference 0.003) and diastolic FA (difference 0.01) were not statistically significantly different between centres (p > 0.05), and only the diastolic ADC showed a statistically significant, but numerically small, difference of 0.07 × 10(-3) mm2/s (p = 0.047). The intercentre, intrasubject coefficients of variance were: systolic ADC 7%, FA 6%; diastolic ADC 7%, FA 3%. CONCLUSIONS This is the first study to demonstrate the accuracy of a stimulated-echo DT-CMR sequence in phantoms, and demonstrates the feasibility of obtaining reproducible ADC and FA in healthy volunteers at separate centres with well-matched sequences and processing.
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Affiliation(s)
- Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Andrew D Scott
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Pedro Ferreira
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Rina Ariga
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Laura-Ann McGill
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Sonia Nielles-Vallespin
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
- National Heart Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), DHHS, Bethesda, MD, USA
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Dudley J Pennell
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Matthew D Robson
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - David N Firmin
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
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30
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Lau AZ, Tunnicliffe EM, Frost R, Koopmans PJ, Tyler DJ, Robson MD. Accelerated human cardiac diffusion tensor imaging using simultaneous multislice imaging. Magn Reson Med 2014; 73:995-1004. [PMID: 24659571 DOI: 10.1002/mrm.25200] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/06/2014] [Accepted: 02/13/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Angus Z. Lau
- Department of Cardiovascular Medicine; Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital; University of Oxford UK
- Department of Physiology; Anatomy, and Genetics; University of Oxford UK
| | - Elizabeth M. Tunnicliffe
- Department of Cardiovascular Medicine; Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital; University of Oxford UK
| | - Robert Frost
- Nuffield Department of Clinical Neurosciences; Oxford Centre for Functional MRI of the Brain; University of Oxford UK
| | - Peter J. Koopmans
- Nuffield Department of Clinical Neurosciences; Oxford Centre for Functional MRI of the Brain; University of Oxford UK
| | - Damian J. Tyler
- Department of Cardiovascular Medicine; Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital; University of Oxford UK
- Department of Physiology; Anatomy, and Genetics; University of Oxford UK
| | - Matthew D. Robson
- Department of Cardiovascular Medicine; Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital; University of Oxford UK
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31
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Tunnicliffe EM, Scott AD, Ferreira P, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin D. Inter-centre reproducibility of cardiac diffusion tensor measures. J Cardiovasc Magn Reson 2014. [PMCID: PMC4044755 DOI: 10.1186/1532-429x-16-s1-o84] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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32
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Banerjee R, Pavlides M, Tunnicliffe EM, Piechnik SK, Sarania N, Philips R, Collier JD, Booth JC, Schneider JE, Wang LM, Delaney DW, Fleming KA, Robson MD, Barnes E, Neubauer S. Multiparametric magnetic resonance for the non-invasive diagnosis of liver disease. J Hepatol 2014; 60:69-77. [PMID: 24036007 PMCID: PMC3865797 DOI: 10.1016/j.jhep.2013.09.002] [Citation(s) in RCA: 301] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 08/23/2013] [Accepted: 09/02/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS With the increasing prevalence of liver disease worldwide, there is an urgent clinical need for reliable methods to diagnose and stage liver pathology. Liver biopsy, the current gold standard, is invasive and limited by sampling and observer dependent variability. In this study, we aimed to assess the diagnostic accuracy of a novel magnetic resonance protocol for liver tissue characterisation. METHODS We conducted a prospective study comparing our magnetic resonance technique against liver biopsy. The individual components of the scanning protocol were T1 mapping, proton spectroscopy and T2* mapping, which quantified liver fibrosis, steatosis and haemosiderosis, respectively. Unselected adult patients referred for liver biopsy as part of their routine care were recruited. Scans performed prior to liver biopsy were analysed by physicians blinded to the histology results. The associations between magnetic resonance and histology variables were assessed. Receiver-operating characteristic analyses were also carried out. RESULTS Paired magnetic resonance and biopsy data were obtained in 79 patients. Magnetic resonance measures correlated strongly with histology (r(s)=0.68 p<0.0001 for fibrosis; r(s)=0.89 p<0.001 for steatosis; r(s)=-0.69 p<0.0001 for haemosiderosis). The area under the receiver operating characteristic curve was 0.94, 0.93, and 0.94 for the diagnosis of any degree of fibrosis, steatosis and haemosiderosis respectively. CONCLUSION The novel scanning method described here provides high diagnostic accuracy for the assessment of liver fibrosis, steatosis and haemosiderosis and could potentially replace liver biopsy for many indications. This is the first demonstration of a non-invasive test to differentiate early stages of fibrosis from normal liver.
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Affiliation(s)
- Rajarshi Banerjee
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK
| | - Michael Pavlides
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK; Translational Gastroenterology Unit, University of Oxford, Level 5, John Radcliffe Hospital, Oxford, UK
| | - Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK
| | - Stefan K Piechnik
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK
| | - Nikita Sarania
- Medical Sciences Division, University of Oxford, Medical Sciences Office, John Radcliffe Hospital, Oxford, UK
| | - Rachel Philips
- Department of Radiology, Churchill Hospital, Old Road, Oxford, UK
| | - Jane D Collier
- Translational Gastroenterology Unit, University of Oxford, Level 5, John Radcliffe Hospital, Oxford, UK
| | - Jonathan C Booth
- Department of Gastroenterology, Royal Berkshire Hospital, London Road, Reading, UK
| | - Jurgen E Schneider
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK
| | - Lai Mun Wang
- Department of Histopathology, John Radcliffe Hospital, Headley Way, Oxford, UK
| | - David W Delaney
- Department of Histopathology, John Radcliffe Hospital, Headley Way, Oxford, UK
| | - Ken A Fleming
- Medical Sciences Division, University of Oxford, Medical Sciences Office, John Radcliffe Hospital, Oxford, UK; Department of Histopathology, John Radcliffe Hospital, Headley Way, Oxford, UK
| | - Matthew D Robson
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK
| | - Eleanor Barnes
- Translational Gastroenterology Unit, University of Oxford, Level 5, John Radcliffe Hospital, Oxford, UK; Oxford NIHR Biomedical Research Centre, Nuffield Department of Medicine, and Peter Medawar Building, University of Oxford, South Parks Rd, Oxford, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, West Wing, Level 6, John Radcliffe Hospital, Oxford, UK.
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Robson MD, Piechnik SK, Tunnicliffe EM, Neubauer S. T1 measurements in the human myocardium: the effects of magnetization transfer on the SASHA and MOLLI sequences. Magn Reson Med 2013; 70:664-70. [PMID: 23857710 DOI: 10.1002/mrm.24867] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 05/17/2013] [Accepted: 06/11/2013] [Indexed: 01/01/2023]
Abstract
PURPOSE Quantitative mapping of the native T1 of the heart using the modified look-locker inversion recovery (MOLLI) technique provides high quality diagnostic information without requiring contrast agents. Previous work has considered the effects of T2 relaxation on MOLLI T1 measurements, finding that the T1 measured by MOLLI is biased, and that Saturation-recovery single-Shot Acquisition generates a more precise T1. However, despite detailed experiments and simulation the exact relaxation times observed in vivo remain unexplained, but might be due to magnetization transfer (MT). METHODS We used an MT simulation based on the Bloch-McConnell equations to evaluate the most common MOLLI and saturation-recovery single-shot acquisition sequence variants. RESULTS For myocardial tissue we find that the T1 measured by saturation-recovery single-shot acquisition is insensitive to MT and T2, whereas MT reduces the T1 measured by MOLLI (>10%) in addition to the effects due to T2 relaxation. CONCLUSIONS The consequences of this T1 underestimation by MOLLI are relevant. Increases in the actual T1 and T2 and decreases in MT will all result in an increase in T1 measured by MOLLI. Myocardial infarction demonstrates increased native T1 and T2 and decreased MT, indicating that these biases enhance the sensitivity of MOLLI to detect this and possibly other cardiovascular disease states.
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Affiliation(s)
- Matthew D Robson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, John Radcliffe Hospital, Oxford, UK
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Tunnicliffe EM, Robson MD. Optimising acquisition parameters for myocardial T2 mapping using T2-prep at 3T. J Cardiovasc Magn Reson 2013. [PMCID: PMC3586956 DOI: 10.1186/1532-429x-15-s1-w10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Young VE, Patterson AJ, Tunnicliffe EM, Sadat U, Graves MJ, Tang TY, Priest AN, Kirkpatrick PJ, Gillard JH. Signal-to-noise ratio increase in carotid atheroma MRI: a comparison of 1.5 and 3 T. Br J Radiol 2012; 85:937-44. [PMID: 22294703 DOI: 10.1259/bjr/70496948] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVES This study reports quantitative comparisons of signal-to-noise ratio (SNR) at 1.5 and 3 T from images of carotid atheroma obtained using a multicontrast, cardiac-gated, blood-suppressed fast spin echo protocol. METHODS 18 subjects, with carotid atherosclerosis (>30% stenosis) confirmed on ultrasound, were imaged on both 1.5 and 3 T systems using phased-array coils with matched hardware specifications. T(1) weighted (T(1)W), T(2) weighted (T(2)W) and proton density-weighted (PDW) images were acquired with identical scan times. Multiple slices were prescribed to encompass both the carotid bifurcation and the plaque. Image quality was quantified using the SNR and contrast-to-noise ratio (CNR). A phantom experiment was also performed to validate the SNR method and confirm the size of the improvement in SNR. Comparisons of the SNR values from the vessel wall with muscle and plaque/lumen CNR measurements were performed at a patient level. To account for the multiple comparisons a Bonferroni correction was applied. RESULTS One subject was excluded from the protocol owing to image quality and protocol failure. The mean improvement in SNR in plaque was 1.9, 2.1 and 2.1 in T(1)W, T(2)W and PDW images, respectively. All plaque SNR improvements were statistically significant at the p<0.05 level. The phantom experiment reported an improvement in SNR of 2.4 for PDW images. CONCLUSIONS Significant gains in SNR can be obtained for carotid atheroma imaging at 3 T compared with 1.5 T. There was also a trend towards increased CNR. However, this was not significant after the application of the Bonferroni correction.
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Affiliation(s)
- V E Young
- Department of Radiology, Addenbrookes Hospital, Cambridge, UK.
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