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Drummond D, Marquant F, Zanelli E, Lozach C, Boddaert N, Taam RA, Neven B, Le Bourgeois M, Hadchouel A, Sarnacki S, Elie C, Delacourt C, Berteloot L. Radiation-free and injection-free imaging of the paediatric chest using a magnetic resonance imaging protocol including zero time echo sequence (3D-ZTE). Eur J Pediatr 2024:10.1007/s00431-024-05678-1. [PMID: 39066822 DOI: 10.1007/s00431-024-05678-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 06/17/2024] [Accepted: 06/30/2024] [Indexed: 07/30/2024]
Abstract
Computed tomography (CT) is commonly used for paediatric thoracic diseases but involves radiation exposure and often requires intravenous contrast. We evaluated the performance of a magnetic resonance imaging (MRI) protocol including a 3D zero echo time (3D-ZTE) sequence for radiation-free and contrast-free imaging of the paediatric chest. In this prospective, single-centre study, children aged 6-16 years underwent chest CT and MRI within 48 h. CT and MRI exams were independently assessed by two paediatric radiologists. The primary outcome was the image quality of the 3D-ZTE sequence using a scoring system based on the acceptability of the images obtained and visibility of bronchial structures, vessels and fissures. Secondary outcomes included radiologists' ability to detect lung lesions on 3D-ZTE MRI images compared with CT images. Seventy-two children were included. Overall, the image quality achieved with the 3D-ZTE MRI sequence was inferior to that of CT for visualising pulmonary structures, with satisfactory lung image quality observed for 81.9% (59/72) and 100% (72/72) of patients, respectively. However, MRI sensitivity was excellent (above 90%) for the detection of certain lesions such as lung consolidation, proximal mucoid impactions, pulmonary cysts, ground glass opacities and honeycombing. Intermodality agreement (MRI versus CT) was consistently higher for the senior reader compared to the junior reader. CONCLUSION Despite its overall lower image quality compared to CT, and the additional years of experience required for accurate interpretation, the 3D-ZTE MRI sequence demonstrated excellent sensitivity for several lesions, making it an appropriate imaging method in certain indications. WHAT IS KNOWN • Chest radiography and CT are the main imaging modalities for paediatric thoracic diseases but involve radiation exposure and CT often requires IV contrast. • MRI is promising for radiation-free lung imaging in children but faces challenges of low signal-to-noise ratio and motion artefacts. WHAT IS NEW • An MRI protocol including a 3D zero echo time (ZTE) sequence allows satisfactory visualisation of lung parenchyma in 82% of children. • Despite overall inferior image quality compared to CT, MRI demonstrated excellent sensitivity for several lesions, making it an appropriate imaging method in certain indications.
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Affiliation(s)
- David Drummond
- Department of Paediatric Pulmonology and Allergology, University Hospital Necker-Enfants Malades, AP-HP, 149 Rue de Sèvres, 75015, Paris, France.
- Université Paris Cité, Paris, France.
- Inserm UMR 1138, Centre de Recherche Des Cordeliers, HeKA Team, 75006, Paris, France.
| | - Fabienne Marquant
- Department of Clinical Research, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Elisa Zanelli
- Department of Paediatric Imaging, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Cécile Lozach
- Department of Paediatric Imaging, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Nathalie Boddaert
- Department of Paediatric Imaging, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Rola Abou Taam
- Department of Paediatric Pulmonology and Allergology, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Bénédicte Neven
- Université Paris Cité, Paris, France
- Paediatric Haematology-Immunology and Rheumatology Unit, Necker-Enfants Malades Hospital, APHP, Paris, France
| | - Muriel Le Bourgeois
- Department of Paediatric Pulmonology and Allergology, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Alice Hadchouel
- Université Paris Cité, Paris, France
- Department of Paediatric Pulmonology and Allergology, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Sabine Sarnacki
- Université Paris Cité, Paris, France
- Department of Paediatric Surgery, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Caroline Elie
- Department of Clinical Research, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Christophe Delacourt
- Université Paris Cité, Paris, France
- Department of Paediatric Pulmonology and Allergology, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
| | - Laureline Berteloot
- Department of Paediatric Imaging, University Hospital Necker-Enfants Malades, AP-HP, Paris, France
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Sodhi KS, Bhatia A, Rana P, Mathew JL. Impact of Radial Percentage K-Space Filling and Signal Averaging on Native Lung MRI Image Quality in 3D Radial UTE Acquisition: A Pilot Study. Acad Radiol 2023; 30:2557-2565. [PMID: 36931950 DOI: 10.1016/j.acra.2023.01.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 01/08/2023] [Accepted: 01/23/2023] [Indexed: 03/18/2023]
Abstract
RATIONALE AND OBJECTIVE To assess the impact of radial percentage k-space filling and signal averaging on lung MRI image quality in 3D radial ultrashort echo-time (UTE) acquisition. MATERIALS AND METHODS In this IRB approved prospective study, 25 patients (10-30 years) referred for MRI examination for indications other than related to lungs were enrolled from January 2021 to November 2021. All the patients underwent lung MRI, using three different UTE sequence parameters with radial (R) percentage of 100 or 200 and number of signal averages (NSA) of one or two. Two radiologists independently assessed the images for the outline of pleural and mediastinal surface, visibility of lung parenchyma, major bronchi, and segmental bronchi. The quality of the images was assessed based on the degree of motion artifacts. For objective assessment, signal-to-noise ratio, contrast-to-noise ratio, and contrast ratio were calculated. RESULTS The outline of pleural and mediastinal surface, lung parenchyma, and segmental bronchi were best demonstrated on R100_NSA2 sequence. The major bronchi were best demonstrated on R100_NSA2 and R100_NSA1 sequences. The intersequence difference was statistically significant for evaluating the pleural and mediastinal surface and segmental bronchi only (p < 0.05). Overall, the best image quality with least artifacts was seen with R100_NSA2 sequence. The objective assessment showed no statistically significant difference between the three sequences (p > 0.05). Interobserver agreement for different findings was substantial to almost perfect for R100_NSA2 and R200_NSA1 sequences. CONCLUSION R100_NSA2 UTE sequence performed best for the evaluation of the different findings and showed the best image quality.
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Affiliation(s)
- Kushaljit Singh Sodhi
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St.Louis, Missouri, USA; Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India.
| | - Anmol Bhatia
- Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Pratyaksha Rana
- Department of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Joseph L Mathew
- Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
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Geiger J, Zeimpekis KG, Jung A, Moeller A, Kellenberger CJ. Clinical application of ultrashort echo-time MRI for lung pathologies in children. Clin Radiol 2021; 76:708.e9-708.e17. [PMID: 34120734 DOI: 10.1016/j.crad.2021.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/20/2021] [Indexed: 01/05/2023]
Abstract
Lung magnetic resonance imaging (MRI) is considered to be challenging, because the low proton density of the tissue, fast signal decay, and respiratory artefacts hamper adequate image quality. MRI of the lungs and thorax is increasingly used in the paediatric population, because it is a radiation-free alternative to chest CT. Recently, ultrashort echo-time (UTE) sequences have been introduced into clinical MRI protocols, in order to improve the contrast-to-noise ratio due to reduced susceptibility artefacts and to depict structural alterations comparable to CT. The purpose of this review is to provide an overview of various clinical conditions and pathologies in the paediatric chest depicted by an UTE sequence, the so-called three-dimensional (3D) Cones sequence, in comparison with conventional MRI sequences. Besides describing typical features of cystic fibrosis, we present UTE application in other more or less common paediatric lung pathologies, for instance, interstitial pneumopathies, pulmonary infections, and congenital pulmonary malformations.
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Affiliation(s)
- J Geiger
- Department of Diagnostic Imaging, University Children's Hospital Zürich, Zürich, Switzerland; University of Zürich, University Children's Hospital Zürich, Zürich, Switzerland.
| | - K G Zeimpekis
- Department of Nuclear Medicine, University Hospital Zürich, Zürich, Switzerland; Department of Electrical Engineering and Information Technology, ETH Zürich, Zürich, Switzerland
| | - A Jung
- University of Zürich, University Children's Hospital Zürich, Zürich, Switzerland; Division of Respiratory Medicine and Cystic Fibrosis, University Children's Hospital Zürich, Zürich, Switzerland
| | - A Moeller
- University of Zürich, University Children's Hospital Zürich, Zürich, Switzerland; Division of Respiratory Medicine and Cystic Fibrosis, University Children's Hospital Zürich, Zürich, Switzerland
| | - C J Kellenberger
- Department of Diagnostic Imaging, University Children's Hospital Zürich, Zürich, Switzerland; University of Zürich, University Children's Hospital Zürich, Zürich, Switzerland
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Zapp J, Domsch S, Weingärtner S, Schad LR. Gaussian signal relaxation around spin echoes: Implications for precise reversible transverse relaxation quantification of pulmonary tissue at 1.5 and 3 Tesla. Magn Reson Med 2016; 77:1938-1945. [DOI: 10.1002/mrm.26280] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 04/22/2016] [Accepted: 04/29/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Jascha Zapp
- Computer Assisted Clinical MedicineHeidelberg UniversityMannheim Germany
| | - Sebastian Domsch
- Computer Assisted Clinical MedicineHeidelberg UniversityMannheim Germany
| | | | - Lothar R. Schad
- Computer Assisted Clinical MedicineHeidelberg UniversityMannheim Germany
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Chen Y, Hamilton AM, Parkins KM, Wang JX, Rogers KA, Zeineh MM, Rutt BK, Ronald JA. MRI and histopathologic study of a novel cholesterol-fed rabbit model of xanthogranuloma. J Magn Reson Imaging 2016; 44:673-82. [PMID: 26921220 DOI: 10.1002/jmri.25213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/10/2016] [Indexed: 12/16/2022] Open
Abstract
PURPOSE To develop a rabbit model of xanthogranuloma based on supplementation of dietary cholesterol. The aim of this study was to analyze the xanthogranulomatous lesions using magnetic resonance imaging (MRI) and histological examination. MATERIALS AND METHODS Rabbits were fed a low-level cholesterol (CH) diet (n = 10) or normal chow (n = 5) for 24 months. In vivo brain imaging was performed on a 3T MR system using fast imaging employing steady state acquisition, susceptibility-weighted imaging, spoiled gradient recalled, T1 -weighted inversion recovery imaging and T1 relaxometry, PD-weighted and T2 -weighted spin-echo imaging and T2 relaxometry, iterative decomposition of water and fat with echo asymmetry and least-squares estimation, ultrashort TE MRI (UTE-MRI), and T2* relaxometry. MR images were evaluated using a Likert scale for lesion presence and quantitative analysis of lesion size, ventricular volume, and T1 , T2 , and T2* values of lesions was performed. After imaging, brain specimens were examined using histological methods. RESULTS In vivo MRI revealed that 6 of 10 CH-fed rabbits developed lesions in the choroid plexus. Region-of-interest analysis showed that for CH-fed rabbits the mean lesion volume was 8.5 ± 2.6 mm(3) and the volume of the lateral ventricle was significantly increased compared to controls (P < 0.01). The lesions showed significantly shorter mean T2 values (35 ± 12 msec, P < 0.001), longer mean T1 values (1581 ± 146 msec, P < 0.05), and shorter T2* values (22 ± 13 msec, P < 0.001) compared to adjacent brain structures. The ultrashort T2* components were visible using UTE-MRI. Histopathologic evaluation of lesions demonstrated features of human xanthogranuloma. CONCLUSION Rabbits fed a low-level CH diet develop sizable intraventricular masses that have similar histopathological features as human xanthogranuloma. Multiparametric MRI techniques were able to provide information about the complex composition of these lesions. J. Magn. Reson. Imaging 2016;44:673-682.
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Affiliation(s)
- Yuanxin Chen
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada
| | - Amanda M Hamilton
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada
| | - Katie M Parkins
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada
| | - Jian-Xiong Wang
- Advanced Imaging Research Center and Radiology Department, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Kem A Rogers
- Department of Anatomy and Cell Biology, Western University, London, Ontario, Canada
| | - Michael M Zeineh
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Brian K Rutt
- Department of Radiology, Stanford University, Stanford, California, USA
| | - John A Ronald
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada
- Department of Medical Biophysics, Western University, London, Ontario, Canada
- Lawson Health Research Institute, London, Ontario, Canada
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Mulkern R, Haker S, Mamata H, Lee E, Mitsouras D, Oshio K, Balasubramanian M, Hatabu H. Lung Parenchymal Signal Intensity in MRI: A Technical Review with Educational Aspirations Regarding Reversible Versus Irreversible Transverse Relaxation Effects in Common Pulse Sequences. CONCEPTS IN MAGNETIC RESONANCE. PART A, BRIDGING EDUCATION AND RESEARCH 2014; 43A:29-53. [PMID: 25228852 PMCID: PMC4163152 DOI: 10.1002/cmr.a.21297] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Lung parenchyma is challenging to image with proton MRI. The large air space results in ~l/5th as many signal-generating protons compared to other organs. Air/tissue magnetic susceptibility differences lead to strong magnetic field gradients throughout the lungs and to broad frequency distributions, much broader than within other organs. Such distributions have been the subject of experimental and theoretical analyses which may reveal aspects of lung microarchitecture useful for diagnosis. Their most immediate relevance to current imaging practice is to cause rapid signal decays, commonly discussed in terms of short T2* values of 1 ms or lower at typical imaging field strengths. Herein we provide a brief review of previous studies describing and interpreting proton lung spectra. We then link these broad frequency distributions to rapid signal decays, though not necessarily the exponential decays generally used to define T2* values. We examine how these decays influence observed signal intensities and spatial mapping features associated with the most prominent torso imaging sequences, including spoiled gradient and spin echo sequences. Effects of imperfect refocusing pulses on the multiple echo signal decays in single shot fast spin echo (SSFSE) sequences and effects of broad frequency distributions on balanced steady state free precession (bSSFP) sequence signal intensities are also provided. The theoretical analyses are based on the concept of explicitly separating the effects of reversible and irreversible transverse relaxation processes, thus providing a somewhat novel and more general framework from which to estimate lung signal intensity behavior in modern imaging practice.
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Affiliation(s)
| | - Steven Haker
- Brigham and Women's Hospital, Radiology, Boston, MA, 02115
| | - Hatsuho Mamata
- Brigham and Women's Hospital, Radiology, Boston, MA, 02115
| | - Edward Lee
- Children's Hospital, Radiology, Boston, MA, 02115
| | | | - Koichi Oshio
- Brigham and Women's Hospital, Radiology, Boston, MA, 02115
| | | | - Hiroto Hatabu
- Brigham and Women's Hospital, Radiology, Boston, MA, 02115
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Yassin A, Pedrosa I, Kearney M, Genega E, Rofsky NM, Lenkinski RE. In vitro MR imaging of renal stones with an ultra-short echo time magnetic resonance imaging sequence. Acad Radiol 2012; 19:1566-72. [PMID: 22959582 DOI: 10.1016/j.acra.2012.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Revised: 07/12/2012] [Accepted: 07/20/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To characterize the magnetic resonance (MR) relaxation times (ie, T1 and T2 relaxation times) of a variety of kidney stone specimens using an ultra-short echo time (UTE) sequence and to correlate these values to their size and composition based on chemical analysis. MATERIALS AND METHODS This was an institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study with waiver of informed consent. Between April 2009 and September 2009, stones from 36 patients underwent 1.5T MR imaging with two UTE pulse sequences to measure: 1) T2 relaxation times (repetition time [TR] = 1 second and multiple echo times [TEs] ranging from 0.1 ms up to 2 ms); 2) T1 relaxation times (TE = 0.1 ms and multiple TRs ranging from 500 ms to 2.5 seconds). A tube containing a solution of water and hydroxyapatite crystals near the stones served as reference standard. Results were compared to previous data obtained from experiments measuring the T1 and T2 of pure calcium oxalate and hydroxyapatite crystals suspended in water. Stones were submitted for chemical analysis. The stone size and composition was correlated to the relaxation time, and signal intensity. RESULTS The average stone size was 0.86 cm (range 0.1-3.3 cm). Twenty-one stones were visible by MR. The average size of MR-visible stones was 1.1 cm (range 0.15-3.3 cm) compared to 0.46 cm (range 0.1-0.9) for nonvisible stones. The mean T1 and T2 of MR-visible stones were 950 ms (range 138-3000 ms) and 3.12 ms (range 0.27-12 ms), respectively. The T1 (mean 1143, range 740-1583) and T1 (mean 8.31, range 4.6-12) values of calcium phosphate were longer than that for other stone compositions T1 (mean 953, range 138-3000) and T2 (mean 2.58, range 0.27-5.8; P < .05). CONCLUSIONS The T1- and T2-relaxation times of kidney stones are variable and depend on their composition and the size of the stones. UTE MR allows for visualization of renal stones in vitro.
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Affiliation(s)
- Aya Yassin
- Department of Radiology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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Coxson HO, Mayo J, Lam S, Santyr G, Parraga G, Sin DD. New and current clinical imaging techniques to study chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2009; 180:588-97. [PMID: 19608719 DOI: 10.1164/rccm.200901-0159pp] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by both small airway and parenchymal abnormalities. There is increasing evidence to suggest that these two morphologic phenotypes, although related, may have different clinical presentations, prognosis, and therapeutic responses to medications. With the advent of novel imaging modalities, it is now possible to evaluate these two morphologic phenotypes in large clinical studies using noninvasive or minimally invasive methods such as computed tomography (CT), magnetic resonance imaging (MRI), and optical coherence tomography (OCT). In this article, we provide an overview of these imaging modalities in the context of COPD and discuss their strengths as well as their limitations for providing quantitative COPD phenotypes.
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Affiliation(s)
- Harvey O Coxson
- Providence Heart and Lung Institute, St. Paul's Hospital, Vancouver, British Columbia, Canada
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Kuethe DO, Adolphi NL, Fukushima E. Short data-acquisition times improve projection images of lung tissue. Magn Reson Med 2007; 57:1058-64. [PMID: 17534926 DOI: 10.1002/mrm.21230] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
MR images of laboratory rat lungs that resolve the thin membranes that separate lung lobes are presented. It appears that the capabilities of in vivo small-animal pulmonary MRI may rival those of in vivo small-animal X-ray CT. Free induction decay (FID)-projection imaging was employed with particular attention to the choice of acquisition time. For a given nominal resolution, one obtains optimal point discrimination when the acquisition time T(acq) normalized by the signal decay time constant T(2)(*) is approximately 0.8-0.9, although a better signal-to-noise ratio (SNR) is obtained when this quotient is 1.6. Currently available equipment should be able to even exceed the results presented herein.
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10
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Robson MD, Bydder GM. Clinical ultrashort echo time imaging of bone and other connective tissues. NMR IN BIOMEDICINE 2006; 19:765-80. [PMID: 17075960 DOI: 10.1002/nbm.1100] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The background underpinning the clinical use of ultrashort echo time, SPRITE and other pulse sequences for imaging bone and other connective tissues with short T2 is reviewed. Features of the basic physics relevant to UTE imaging are described, including the consequences when the radiofrequency pulse duration is of the order of T2 so that rotation of tissue magnetization into the transverse plane is incomplete. Consequences of the broad linewidth of short T2 components are also discussed, including partial saturation by off-resonance fat suppression pulses as well as those used in multislice and multiecho imaging. The need for rapid data acquisition of the order of T2 is explained. The basic two-dimensional UTE pulse sequence with its half excitation pulse and radial imaging from the centre of k-space is described, together with options that suppress fat and/or reduce the signal from long T2 components. The basic features of SPRITE and other sequences with very short TE are described. Image interpretation is discussed. Clinical features of the imaging of cortical bone, tendons, ligaments, menisci, periosteum and the spine are illustrated. The source of the short T2 signal in these tissues is predominantly collagen and water tightly bound to collagen. Short T2 components in all of these tissues are detectible and may show high signals. Possible future developments are outlined, as are technical limitations of clinical magnetic resonance systems.
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Affiliation(s)
- Matthew D Robson
- Oxford University Centre for Clinical Magnetic Resonance Research, OCMR Unit, John Radcliffe Hospital, Oxford OX3 9DU, UK
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11
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Lutterbey G, Grohé C, Gieseke J, von Falkenhausen M, Morakkabati N, Wattjes MP, Manka R, Trog D, Schild HH. Initial experience with lung-MRI at 3.0T: Comparison with CT and clinical data in the evaluation of interstitial lung disease activity. Eur J Radiol 2006; 61:256-61. [PMID: 17034975 DOI: 10.1016/j.ejrad.2006.09.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2006] [Revised: 08/29/2006] [Accepted: 09/13/2006] [Indexed: 11/20/2022]
Abstract
OBJECTIVES We evaluated the feasibility of highfield lung-MRI at 3.0T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. MATERIAL AND METHODS Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR=80/1500-2500 ms, 22 transverse slices, 7/2mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A=temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B=burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. RESULTS The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). CONCLUSION Highfield MRI of the lung is feasible and performed slightly better compared to CT in the determination of activity in patients with interstitial lung diseases.
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Affiliation(s)
- G Lutterbey
- Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn, Germany.
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12
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Huang MQ, Basse PH, Yang Q, Horner JA, Hichens TK, Ho C. MRI detection of tumor in mouse lung using partial liquid ventilation with a perfluorocarbon-in-water emulsion. Magn Reson Imaging 2004; 22:645-52. [PMID: 15172058 DOI: 10.1016/j.mri.2004.01.041] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2003] [Accepted: 01/29/2004] [Indexed: 11/25/2022]
Abstract
Transverse relaxation time (T(2*))-weighted (1)H-MRI of mouse lungs has been performed using partial liquid ventilation (PLV) with a perfluorocarbon (PFC)-in-water emulsion as a contrast modality for lung MRI. Significant sensitivity enhancement in MRI of mouse lungs has been demonstrated with the protocol. The results show that the T(2*) value in lung is approximately proportional to the infusion dose up to a dose of 5 ml/kg body weight (BW) (4.5 g PFC/kg BW) and becomes essentially constant beyond this dosage. T(2*) maps of lungs have been calculated and T(2*) in lungs is in the range of 10-35 ms with this technique, which is an order of magnitude greater than the T(2*) value of mouse lungs without using a PFC-in-water emulsion. T(2*)-weighted (1)H-MR images of mouse lungs have been obtained with good quality under our experimental conditions. We have applied this technique to detect tumors in mouse lungs. Our technique can detect small lung tumors of B16 melanoma, about 1 mm in diameter, in mice. With its significant MR sensitivity enhancement and technical simplicity, T(2*)-weighted (1)H-MRI using PLV with PFC-in-water emulsion offers a promising approach to investigate lung cancers using rodent models.
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Affiliation(s)
- Ming Qiang Huang
- Department of Biological Sciences, Pittsburgh NMR Center for Biomedical Research, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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Ward ER, Hedlund LW, Kurylo WC, Wheeler CT, Cofer GP, Dewhirst MW, Marks LB, Vujaskovic Z. Proton and hyperpolarized helium magnetic resonance imaging of radiation-induced lung injury in rats. Int J Radiat Oncol Biol Phys 2004; 58:1562-9. [PMID: 15050337 DOI: 10.1016/j.ijrobp.2003.12.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2003] [Revised: 11/20/2003] [Accepted: 12/01/2003] [Indexed: 10/26/2022]
Abstract
PURPOSE To assess the usefulness of hyperpolarized helium (3He) MRI, including apparent diffusion coefficient measurements, in the detection and evaluation of radiation-induced lung injury in rats. METHODS AND MATERIALS Female Fischer-344 rats were treated to the right lung with fractionated dose of 40 Gy (5 x 8 Gy) using 4-MV photons. Conventional proton (1H) and hyperpolarized (3He) MRI were used to image the lungs 3-6 months after radiation treatment. Apparent diffusion coefficient (ADC) maps of hyperpolarized 3He in the lungs were calculated using a nonlinear, least-squares fitting routine on a pixel-by-pixel basis. After imaging, lungs were processed for histologic assessment of damage. RESULTS The effect of radiation was time dependent with progressive right lung damage ranging from mild to moderate at 3 months to severe fibrosis with structural deformation at 6 months after radiation. There was a significant decrease in the apparent diffusion coefficient of hyperpolarized 3He gas in radiation-treated lungs. Areas of decreased ADC in the lungs correlated with fibrosis shown by histology. CONCLUSION This is the first study to show that hyperpolarized 3He MRI can detect radiation-induced lung injury noninvasively. Reduced hyperpolarized 3He ADC values postradiation likely reflect reduced alveolar volumes associated with fibrosis of the interstitium. Future studies at earlier time points may determine whether this noninvasive imaging technique can detect lung damage before clinical symptoms. Development of this new approach of magnetic resonance lung imaging in the rat model of radiation-induced lung injury will increase the ability to develop appropriate algorithms and more accurate models of the normal tissue complication probability.
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Affiliation(s)
- Erika R Ward
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
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Robson MD, Gatehouse PD, Bydder M, Bydder GM. Magnetic Resonance: An Introduction to Ultrashort TE (UTE) Imaging. J Comput Assist Tomogr 2003; 27:825-46. [PMID: 14600447 DOI: 10.1097/00004728-200311000-00001] [Citation(s) in RCA: 492] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The background underpinning the clinical use of ultrashort echo-time (UTE) pulse sequences for imaging tissues or tissue components with short T2s is reviewed. Tissues properties are discussed, and tissues are divided into those with a majority of short T2 relaxation components and those with a minority. Features of the basic physics relevant to UTE imaging are described including the fact that when the radiofrequency pulse duration is of the order T2, rotation of tissue magnetization into the transverse plane is incomplete. Consequences of the broad line-width of short T2 components are also discussed including their partial saturation by off-resonance fat suppression pulses as well as multislice and multiecho imaging. The need for rapid data acquisition of the order T2 is explained. The basic UTE pulse sequence with its half excitation pulse and radial imaging from the center of k-space is described together with options that suppress fat and/or long T2 components. Image interpretation is discussed. Clinical features of the imaging of cortical bone, tendons, ligaments, menisci, and periosteum as well as brain, liver, and spine are illustrated. Short T2 components in all of these tissues may show high signals. Possible future developments are outlined as are technical limitations.
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Affiliation(s)
- Matthew D Robson
- Oxford University Center for Clinical Magnetic Resonance Research, MRS Unit, John Radcliffe Hospital
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