1
|
Katyal A, Calic Z, Killingsworth M, Bhaskar SMM. Diagnostic and prognostic utility of computed tomography perfusion imaging in posterior circulation acute ischemic stroke: A systematic review and meta-analysis. Eur J Neurol 2021; 28:2657-2668. [PMID: 34021664 DOI: 10.1111/ene.14934] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/10/2021] [Accepted: 05/14/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Computed tomography perfusion (CTP) imaging could be useful in the diagnosis of posterior circulation stroke (PCS) and in identifying patients who are likely to experience favorable outcomes following reperfusion therapy. The current study sought to investigate the diagnostic and prognostic capability of CTP in acute ischemic PCS by performing a systematic review and meta-analysis. METHODS Medline/PubMed and the Cochrane Library were searched using the terms: "posterior circulation", "CT perfusion", "acute stroke", and "reperfusion therapy". The following studies were included: (1) patients aged 18 years or above; (2) patients diagnosed with PCS; and (3) studies with good methodological design. Pooled sensitivity (SENS), specificity (SPEC), and area under the curve (AUC), computed using the summary receiver operating characteristic (SROC) curves, were used to determine diagnostic/prognostic capability. RESULTS Out of 14 studies included, a meta-analysis investigating diagnostic accuracy of CTP was performed on nine studies. Meta-analysis demonstrated comparable diagnostic accuracy of CTP to non-contrast computed tomography (NCCT) (AUCCTP : 0.90 [95% CI 0.87-0.92] vs. AUCNCCT : 0.96 [95% CI 0.94-0.97]); however, with higher pooled sensitivity (SENSCTP : 72% [95% CI 57%-83%] vs. SENSNCCT : 25% [95% CI 17%-35%]) and lower specificity (SPECCTP : 90% [95% CI 83%-94%] vs. SPECNCCT : 96% [95% CI 95%-98%]) than NCCT. Meta-analysis to determine prognostic capability of CTP could not be performed. CONCLUSIONS CTP has limited diagnostic utility in acute ischemic PCS, albeit with superior diagnostic sensitivity and inferior diagnostic specificity to NCCT. Further prospective trials are required to validate the prognostic capability of CTP-derived parameters in PCS.
Collapse
Affiliation(s)
- Anubhav Katyal
- Neurovascular Imaging Laboratory, Clinical Sciences Stream, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.,South Western Sydney Clinical School, UNSW Medicine, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Zeljka Calic
- Neurovascular Imaging Laboratory, Clinical Sciences Stream, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.,South Western Sydney Clinical School, UNSW Medicine, University of New South Wales (UNSW), Sydney, NSW, Australia.,Department of Neurology & Neurophysiology, Liverpool Hospital & South Western Sydney Local Health District, Sydney, NSW, Australia.,Stroke & Neurology Research Group, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia
| | - Murray Killingsworth
- Neurovascular Imaging Laboratory, Clinical Sciences Stream, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.,South Western Sydney Clinical School, UNSW Medicine, University of New South Wales (UNSW), Sydney, NSW, Australia.,NSW Brain Clot Bank, NSW Health Pathology and NSW Health Statewide Biobank, Sydney, NSW, Australia.,Correlative Microscopy Facility, Ingham Institute for Applied Medical Research and Department of Anatomical Pathology, NSW Health Pathology and Liverpool Hospital, Liverpool, NSW, Australia
| | - Sonu Menachem Maimonides Bhaskar
- Neurovascular Imaging Laboratory, Clinical Sciences Stream, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.,Department of Neurology & Neurophysiology, Liverpool Hospital & South Western Sydney Local Health District, Sydney, NSW, Australia.,Stroke & Neurology Research Group, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.,NSW Brain Clot Bank, NSW Health Pathology and NSW Health Statewide Biobank, Sydney, NSW, Australia
| |
Collapse
|
2
|
Lin SF, Chen CI, Hu HH, Bai CH. Predicting functional outcomes of posterior circulation acute ischemic stroke in first 36 h of stroke onset. J Neurol 2018; 265:926-932. [PMID: 29455362 PMCID: PMC5878189 DOI: 10.1007/s00415-018-8746-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/10/2018] [Accepted: 01/10/2018] [Indexed: 11/27/2022]
Abstract
Posterior circulation acute ischemic stroke constitutes one-fourth of all ischemic strokes and can be efficiently quantified using the posterior circulation Alberta stroke program early computed tomography score (PC-ASPECTS) through diffusion-weighted imaging. We investigated whether the PC-ASPECTS and National Institutes of Health Stroke Scale (NIHSS) facilitate functional outcome prediction among Chinese patients with posterior circulation acute ischemic stroke. Participants were selected from our prospective stroke registry from January 1, 2015, to December 31, 2016. The baseline NIHSS score was assessed on the first day of admission, and brain magnetic resonance imaging was performed within 36 h after stroke onset. Simple and multiple logistic regressions were conducted to determine stroke risk factors and the PC-ASPECTS. Receiver operating characteristics (ROC) curve analysis was performed to compare the NIHSS and PC-ASPECTS. Of 549 patients from our prospective stroke admission registry database, 125 (22.8%) had a diagnosis of posterior circulation acute ischemic stroke. The optimal cutoff for the PC-ASPECTS in predicting outcomes was 7. The odds ratios of the PC-ASPECTS (≤ 7 vs > 7) in predicting outcomes were 6.33 (p = 0.0002) and 8.49 (p = 0.0060) in the univariate and multivariate models, respectively, and 7.52 (p = 0.0041) in the aging group. On ROC curve analysis, the PC-ASPECTS demonstrated more reliability than the baseline NIHSS for predicting functional outcomes of minor posterior circulation stroke. In conclusion, both the PC-ASPECTS and NIHSS help clinicians predict functional outcomes. PC-ASPECTS > 7 is a helpful discriminator for achieving favorable functional outcome prediction in posterior circulation acute ischemic stroke.
Collapse
Affiliation(s)
- Sheng-Feng Lin
- School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan
| | - Chin-I Chen
- Department of Neurology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Neurology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Han-Hwa Hu
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Research Center of Cerebrovascular Disease Treatment, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Neurology, Taipei Medical University-Shaung Ho Hospital, Taipei, Taiwan
| | - Chyi-Huey Bai
- School of Public Health, College of Public Health, Taipei Medical University, Taipei, Taiwan. .,Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei City, 110, Taiwan.
| |
Collapse
|
3
|
Quantitative T2* mapping reveals early temporo-spatial dynamics in an ischemic stroke model. J Neurosci Methods 2016; 259:83-89. [DOI: 10.1016/j.jneumeth.2015.11.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 11/18/2015] [Accepted: 11/20/2015] [Indexed: 11/17/2022]
|
4
|
Schaefer PW, Souza L, Kamalian S, Hirsch JA, Yoo AJ, Kamalian S, Gonzalez RG, Lev MH. Limited reliability of computed tomographic perfusion acute infarct volume measurements compared with diffusion-weighted imaging in anterior circulation stroke. Stroke 2014; 46:419-24. [PMID: 25550366 DOI: 10.1161/strokeaha.114.007117] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Diffusion-weighted imaging (DWI) can reliably identify critically ischemic tissue shortly after stroke onset. We tested whether thresholded computed tomographic cerebral blood flow (CT-CBF) and CT-cerebral blood volume (CT-CBV) maps are sufficiently accurate to substitute for DWI for estimating the critically ischemic tissue volume. METHODS Ischemic volumes of 55 patients with acute anterior circulation stroke were assessed on DWI by visual segmentation and on CT-CBF and CT-CBV with segmentation using 15% and 30% thresholds, respectively. The contrast:noise ratios of ischemic regions on the DWI and CT perfusion (CTP) images were measured. Correlation and Bland-Altman analyses were used to assess the reliability of CTP. RESULTS Mean contrast:noise ratios for DWI, CT-CBF, and CT-CBV were 4.3, 0.9, and 0.4, respectively. CTP and DWI lesion volumes were highly correlated (R(2)=0.87 for CT-CBF; R(2)=0.83 for CT-CBV; P<0.001). Bland-Altman analyses revealed little systemic bias (-2.6 mL) but high measurement variability (95% confidence interval, ±56.7 mL) between mean CT-CBF and DWI lesion volumes, and systemic bias (-26 mL) and high measurement variability (95% confidence interval, ±64.0 mL) between mean CT-CBV and DWI lesion volumes. A simulated treatment study demonstrated that using CTP-CBF instead of DWI for detecting a statistically significant effect would require at least twice as many patients. CONCLUSIONS The poor contrast:noise ratios of CT-CBV and CT-CBF compared with those of DWI result in large measurement error, making it problematic to substitute CTP for DWI in selecting individual acute stroke patients for treatment. CTP could be used for treatment studies of patient groups, but the number of patients needed to identify a significant effect is much higher than the number needed if DWI is used.
Collapse
Affiliation(s)
- Pamela W Schaefer
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston.
| | - Leticia Souza
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Shervin Kamalian
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Joshua A Hirsch
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Albert J Yoo
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Shahmir Kamalian
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - R Gilberto Gonzalez
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Michael H Lev
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston
| |
Collapse
|
5
|
Jakola AS, Berntsen EM, Christensen P, Gulati S, Unsgård G, Kvistad KA, Solheim O. Surgically acquired deficits and diffusion weighted MRI changes after glioma resection--a matched case-control study with blinded neuroradiological assessment. PLoS One 2014; 9:e101805. [PMID: 24992634 PMCID: PMC4081783 DOI: 10.1371/journal.pone.0101805] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 06/11/2014] [Indexed: 11/19/2022] Open
Abstract
Background Acquired deficits following glioma resection may not only occur due to accidental resection of normal brain tissue. The possible importance of ischemic injuries in causing neurological deficits after brain tumor surgery is not much studied. We aimed to study the volume and frequency of early postoperative circulatory changes (i.e. infarctions) detected by diffusion weighted resonance imaging (DWI) in patients with surgically acquired neurological deficits compared to controls. Methods We designed a 1∶1 matched case-control study in patients with diffuse gliomas (WHO grade II–IV) operated with 3D ultrasound guided resection. 42 consecutive patients with acquired postoperative dysphasia and/or new motor deficits were compared to 42 matched controls without acquired deficits. Controls were matched with respect to histopathology, preoperative tumor volumes, and eloquence of location. Two independent radiologists blinded for clinical status assessed the postoperative DWI findings. Results Postoperative peri-tumoral infarctions were more often seen in patients with acquired deficits (63% versus 41%, p = 0.046) and volumes of DWI abnormalities were larger in cases than in controls with median 1.08 cm3 (IQR 0–2.39) versus median 0 cm3 (IQR 0–1.67), p = 0.047. Inter-rater agreement was substantial (67/82, κ = 0.64, p<0.001) for diagnosing radiological significant DWI abnormalities. Conclusion Peri-tumoral infarctions were more common and were larger in patients with acquired deficits after glioma surgery compared to glioma patients without deficits when assessed by early postoperative DWI. Infarctions may be a frequent and underestimated cause of acquired deficits after glioma resection. DWI changes may be an attractive endpoint in brain tumor surgery with both good inter-rater reliability among radiologists and clinical relevance.
Collapse
Affiliation(s)
- Asgeir S. Jakola
- Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway
- MI Lab, Norwegian University of Science and Technology, Trondheim, Norway
- National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway
- * E-mail:
| | - Erik M. Berntsen
- Department of Radiology, St. Olavs University Hospital, Trondheim, Norway
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Pål Christensen
- Department of Radiology, St. Olavs University Hospital, Trondheim, Norway
| | - Sasha Gulati
- Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway
| | - Geirmund Unsgård
- Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway
- National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway
- Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - Kjell A. Kvistad
- Department of Radiology, St. Olavs University Hospital, Trondheim, Norway
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ole Solheim
- Department of Neurosurgery, St. Olavs University Hospital, Trondheim, Norway
- MI Lab, Norwegian University of Science and Technology, Trondheim, Norway
- National Centre for Ultrasound and Image Guided Therapy, Trondheim, Norway
| |
Collapse
|
6
|
Mair G, Wardlaw JM. Imaging of acute stroke prior to treatment: current practice and evolving techniques. Br J Radiol 2014; 87:20140216. [PMID: 24936980 DOI: 10.1259/bjr.20140216] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Standard imaging in acute stroke is undertaken with the aim of diagnosing the underlying cause and excluding stroke mimics. In the presence of ischaemic stroke, imaging is also needed to assess patient suitability for treatment with intravenous thrombolysis. Non-contrast CT is predominantly used, but MRI can also exclude any contraindications to thrombolysis treatment. Advanced stroke imaging such as CT and MR angiography and perfusion imaging are increasingly used in an acute setting. In this review, we discuss the evidence for the application of these advanced techniques in the imaging of acute stroke.
Collapse
Affiliation(s)
- G Mair
- Brain Research Imaging Centre, Division of Neuroimaging Sciences, Centre for Clinical Brain Science, University of Edinburgh, Western General Hospital, Edinburgh, UK
| | | |
Collapse
|
7
|
Arsava EM, Ballabio E, Benner T, Cole JW, Delgado-Martinez MP, Dichgans M, Fazekas F, Furie KL, Illoh K, Jood K, Kittner S, Lindgren AG, Majersik JJ, Macleod MJ, Meurer WJ, Montaner J, Olugbodi AA, Pasdar A, Redfors P, Schmidt R, Sharma P, Singhal AB, Sorensen AG, Sudlow C, Thijs V, Worrall BB, Rosand J, Ay H. The Causative Classification of Stroke system: an international reliability and optimization study. Neurology 2010; 75:1277-84. [PMID: 20921513 DOI: 10.1212/wnl.0b013e3181f612ce] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Valid and reliable ischemic stroke subtype determination is crucial for well-powered multicenter studies. The Causative Classification of Stroke System (CCS, available at http://ccs.mgh.harvard.edu) is a computerized, evidence-based algorithm that provides both causative and phenotypic stroke subtypes in a rule-based manner. We determined whether CCS demonstrates high interrater reliability in order to be useful for international multicenter studies. METHODS Twenty members of the International Stroke Genetics Consortium from 13 centers in 8 countries, who were not involved in the design and development of the CCS, independently assessed the same 50 consecutive patients with acute ischemic stroke through reviews of abstracted case summaries. Agreement among ratings was measured by kappa statistic. RESULTS The κ value for causative classification was 0.80 (95% confidence interval [CI] 0.78-0.81) for the 5-subtype, 0.79 (95% CI 0.77-0.80) for the 8-subtype, and 0.70 (95% CI 0.69-0.71) for the 16-subtype CCS. Correction of a software-related factor that generated ambiguity improved agreement: κ = 0.81 (95% CI 0.79-0.82) for the 5-subtype, 0.79 (95% CI 0.77-0.80) for the 8-subtype, and 0.79 (95% CI 0.78-0.80) for the 16-subtype CCS. The κ value for phenotypic classification was 0.79 (95% CI 0.77-0.82) for supra-aortic large artery atherosclerosis, 0.95 (95% CI 0.93-0.98) for cardioembolism, 0.88 (95% CI 0.85-0.91) for small artery occlusion, and 0.79 (0.76-0.82) for other uncommon causes. CONCLUSIONS CCS allows classification of stroke subtypes by multiple investigators with high reliability, supporting its potential for improving stroke classification in multicenter studies and ensuring accurate means of communication among different researchers, institutions, and eras.
Collapse
Affiliation(s)
- E M Arsava
- A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Brazzelli M, Sandercock PA, Chappell FM, Celani MG, Righetti E, Arestis N, Wardlaw JM, Deeks JJ. Magnetic resonance imaging versus computed tomography for detection of acute vascular lesions in patients presenting with stroke symptoms. Cochrane Database Syst Rev 2009:CD007424. [PMID: 19821415 DOI: 10.1002/14651858.cd007424.pub2] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Magnetic resonance imaging (MRI) is increasingly used for the diagnosis of acute ischaemic stroke but its sensitivity for the early detection of intracerebral haemorrhage has been debated. Computed tomography (CT) is extensively used in the clinical management of acute stroke, especially for the rapid exclusion of intracerebral haemorrhage. OBJECTIVES To compare the diagnostic accuracy of diffusion-weighted MRI (DWI) and CT for acute ischaemic stroke, and to estimate the diagnostic accuracy of MRI for acute haemorrhagic stroke. SEARCH STRATEGY We searched MEDLINE and EMBASE (January 1995 to March 2009) and perused bibliographies of relevant studies for additional references. SELECTION CRITERIA We selected studies that either compared DWI and CT in the same patients for detection of ischaemic stroke or examined the utility of MRI for detection of haemorrhagic stroke, had imaging performed within 12 hours of stroke onset, and presented sufficient data to allow construction of contingency tables. DATA COLLECTION AND ANALYSIS Three authors independently extracted data on study characteristics and measures of accuracy. We assessed data on ischaemic stroke using random-effects and fixed-effect meta-analyses. MAIN RESULTS Eight studies with a total of 308 participants met our inclusion criteria. Seven studies contributed to the assessment of ischaemic stroke and two studies to the assessment of haemorrhagic stroke. The spectrum of patients was relatively narrow in all studies, sample sizes were small, there was substantial incorporation bias, and blinding procedures were often incomplete. Amongst the patients subsequently confirmed to have acute ischaemic stroke (161/226), the summary estimates for DWI were: sensitivity 0.99 (95% CI 0.23 to 1.00), specificity 0.92 (95% CI 0.83 to 0.97). The summary estimates for CT were: sensitivity 0.39 (95% CI 0.16 to 0.69), specificity 1.00 (95% CI 0.94 to 1.00). The two studies on haemorrhagic stroke reported high estimates for diffusion-weighted and gradient-echo sequences but had inconsistent reference standards. We did not calculate overall estimates for these two studies. We were not able to assess practicality or cost-effectiveness issues. AUTHORS' CONCLUSIONS DWI appears to be more sensitive than CT for the early detection of ischaemic stroke in highly selected patients. However, the variability in the quality of included studies and the presence of spectrum and incorporation biases render the reliability and generalisability of observed results questionable. Further well-designed studies without methodological biases, in more representative patient samples, with practicality and cost estimates are now needed to determine which patients should undergo MRI and which CT in suspected acute stroke.
Collapse
Affiliation(s)
- Miriam Brazzelli
- Division of Clinical Neurosciences, University of Edinburgh, Bramwell Dott Building, Western General Hospital, Crewe Road, Edinburgh, UK, EH4 2XU
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Sibon I, Ménégon P, Orgogozo JM, Asselineau J, Rouanet F, Renou P, Tourdias T, Pachai C, Chêne G, Dousset V. Inter- and intraobserver reliability of five MRI sequences in the evaluation of the final volume of cerebral infarct. J Magn Reson Imaging 2009; 29:1280-4. [PMID: 19472382 DOI: 10.1002/jmri.21779] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To evaluate the reproducibility of fluid attenuated inversion recovery (FLAIR) and four other magnetic resonance imaging (MRI) sequences in the quantitative assessment of final cerebral infarct volume. MATERIALS AND METHODS FLAIR, T1-3D, magnetization transfer ratio (MTR)-map, diffusion-weighted trace (DWI)-trace, and apparent diffusion coefficient (ADC)-map, were acquired and measured in 33 patients 30-45 days after onset of a first-ever ischemic stroke. The infarct area was visually detected and manually delineated two times by two readers separately after images and sequences randomization. The reliability was assessed by using an intraclass correlation coefficient (ICC) and its two-sided 95% confidence interval (95% CI). RESULTS DWI-trace had the best reliability, with an ICC of 0.96 (95% CI = 0.93-0.98). FLAIR had an ICC of 0.86 (95% CI = 0.73-0.93), and a much higher volume. T1-3D, MTR-map and ADC-map had lower reliability or excessive volume values equal to 0 in comparison to DWI-trace. CONCLUSION DWI-trace performed within 30th and 45th day following onset of acute ischemic stroke was the most reliable sequence for final infarct volume quantification. This sequence should be added to FLAIR evaluation to strengthen the statistical results of the pharmacological trials and reduce their variability.
Collapse
Affiliation(s)
- Igor Sibon
- CHU Bordeaux, Department of Clinical Neurosciences, Bordeaux, France.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Bra°tane BT, Bastan B, Fisher M, Bouley J, Henninger N. Ischemic lesion volume determination on diffusion weighted images vs. apparent diffusion coefficient maps. Brain Res 2009; 1279:182-8. [DOI: 10.1016/j.brainres.2009.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 05/01/2009] [Accepted: 05/02/2009] [Indexed: 10/20/2022]
|
11
|
Abstract
INTRODUCTION Cerebral perfusion imaging using magnetic resonance imaging (MRI) is widely used in the research and clinical fields to assess the profound changes in blood flow related to ischemic events such as acute stroke, chronic steno-occlusive disease, vasospasm, and abnormal vessel formations from congenital conditions or tumoral neovascularity. With continuing improvements in the precision of MRI-based perfusion techniques, it is increasingly feasible to use this tool in the study of the subtle brain perfusion changes occurring in psychiatric illnesses. This article aims to review the existing literature on applications of perfusion MRI in psychiatric disorder and substance abuse research. The article also provides a brief introductory overview of dynamic susceptibility contrast MRI and arterial spin labeling techniques. An outlook of necessary steps to bring perfusion MRI into the realm of clinical psychiatry as a diagnostic tool is brought forth. Opportunities for research in unexplored disorders and with higher field strengths are briefly examined. METHODS PubMed, ISI Web of Knowledge & Scopus were used to search the literature and cross reference several neuropsychiatric disorders with a search term construct, including "magnetic resonance imaging," "dynamic susceptibility contrast," "arterial spin labeling," perfusion or "cerebral blood flow" or "cerebral blood volume" or "mean transit time." The list of disorders used in the search included schizophrenia, depression and bipolar disorder, dementia and Alzheimer's disease, Parkinson's disease, posttraumatic stress disorder, autism, Asperger disease, attention deficit, Tourette syndrome, obsessive-compulsive disorder, Huntington's disease, bulimia nervosa, anorexia nervosa, and substance abuse. For each disorder for which perfusion MRI studies were found, a brief overview of the disorder symptoms, treatment, prevalence, and existing models is provided, and previous findings from nuclear medicine-based perfusion imaging are overviewed. Findings of perfusion MRI studies are then summarized, and overlap of findings are discussed. Overarching conclusions are made, or an outlook for future work in the area is offered, where appropriate. RESULTS Despite the now fairly broad availability of perfusion MRI, only a limited number of studies were found using this technology. The search produced 13 studies of schizophrenia, 7 studies in major depression, 12 studies in Alzheimer's disease, and 2 studies in Parkinson's disease. Drug abuse and other disorders have mainly been studied with nuclear medicine-based perfusion imaging. The literature concerning the use of perfusion imaging in psychiatry has not been reviewed in the last 5 years or more. The use of MRI for perfusion measurements in psychiatry has not been reviewed in 10 years. CONCLUSIONS Although MRI-based perfusion imaging in psychiatry has mainly been used as a research tool, a path is progressively being cleared for its application in clinical diagnostic and treatment monitoring. The precision of perfusion MRI methods now rivals that of nuclear medicine-based perfusion imaging techniques. Because of their noninvasive nature, arterial spin labeling methods have gained popularity in studies of neuropsychiatric disorders such as schizophrenia, depression, Alzheimer's, and Parkinson's diseases. Perfusion imaging measurements have yet to be included within the diagnostic criteria of neuropsychiatric disorders despite having shown to have great discriminant power in specific disorders. As this young methodology continues to improve and research studies demonstrate the correlation of measured perfusion abnormalities to microcirculatory abnormalities and neuropsychiatric symptomatology, the idea of including such a test within diagnostic criteria for certain mental illnesses becomes increasingly plausible.
Collapse
|
12
|
Puetz V, Gahn G, Becker U, Mucha D, Mueller A, Weir NU, Wiedemann B, von Kummer R. Endovascular therapy of symptomatic intracranial stenosis in patients with impaired regional cerebral blood flow or failure of medical therapy. AJNR Am J Neuroradiol 2008; 29:273-80. [PMID: 17989370 DOI: 10.3174/ajnr.a0829] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND PURPOSE Symptomatic intracranial stenoses have a high risk for a recurrent stroke if treated medically. Although angioplasty and stent placement are proposed treatment options, data on longer-term outcome are limited. MATERIALS AND METHODS We analyzed all endovascular procedures on symptomatic intracranial stenosis at our institution from January 1998 to December 2005. We retrospectively assigned patients to group A (symptoms despite antithrombotic therapy) or group B (impaired regional cerebral blood flow [rCBF]). Primary outcome events were periprocedural major complications or recurrent ischemic strokes in the territory of the treated artery. We used the Kaplan-Meier method to calculate survival probabilities. RESULTS The procedural technical success rate was 92% (35/38) with periprocedural major complications in 4 cases (10.5%; group A [8.3%, 2/24], group B [14.3%, 2/14]). Median (range) follow-up for the 33 patients with technically successful procedures was 21 (0-72) months. Recurrent ischemic strokes occurred in 15% (3/20) of patients in group A and 0% (0/13) of patients in group B. Overall, there were 21% (7/33) primary outcome events (group A [25%, 5/20], group B [15%, 2/13]). There was a nonsignificant trend for better longer-term survival free of a major complication or recurrent stroke in patients with impaired rCBF compared with patients who were refractory to medical therapy treatment (Kaplan-Meier estimate 0.85 [SE 0.10] vs 0.72 [SE 0.11] at 2 years, respectively). CONCLUSION Interventional treatment of symptomatic intracranial stenosis carries significant risk for complications and recurrent stroke in high-risk patients. The observation that patients with impaired rCBF may have greater longer-term benefit than medically refractory deserves further study.
Collapse
Affiliation(s)
- V Puetz
- Department of Neurology, Dresden Stroke Center,University of Technology, Dresden, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Messé SR, Kasner SE, Chalela JA, Cucchiara B, Demchuk AM, Hill MD, Warach S. CT-NIHSS mismatch does not correlate with MRI diffusion-perfusion mismatch. Stroke 2007; 38:2079-84. [PMID: 17540971 DOI: 10.1161/strokeaha.106.480731] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE MRI diffusion-perfusion mismatch may identify patients for thrombolysis beyond 3 hours. However, MRI has limited availability in many hospitals. We investigated whether mismatch between the Alberta Stroke Program Early CT Score (ASPECTS) and the NIH Stroke Scale (NIHSS) correlates with MRI diffusion-perfusion mismatch. METHODS We retrospectively analyzed a cohort of consecutive acute ischemic stroke patients who underwent MRI and CT at admission. NIHSS was performed by the admitting physician. MRI and CT were reviewed by 2 blinded expert raters. Degree of MRI mismatch was defined as present (> 25%) or absent (<25%). Univariate and multivariate analyses were performed to determine characteristics associated with MRI mismatch. Probability of MRI mismatch was calculated for all combinations of ASPECTS and NIHSS cutoff scores. RESULTS Included in the analysis were 143 patients. Median NIHSS on admission was 4 (IQR, 2 to 10); median ASPECTS was 10 (IQR, 9 to 10). Median time to completion of MRI and CT was 4.5 (2.5 to 13.9) hours after onset. CT and MRI were separated by a median of 35 (IQR, 29 to 44) minutes. MRI mismatch was present in 41% of patients. In multivariate analysis, only shorter time-to-scan (OR, 0.96 per hour; 95% CI, 0.92 to 1.0; P=0.043) was associated with MRI mismatch. There was no combination of NIHSS and ASPECTS thresholds that was significantly associated with MRI mismatch. CONCLUSIONS ASPECTS-NIHSS mismatch did not correlate with MRI diffusion-perfusion mismatch in this clinical cohort. MRI mismatch was associated with decreasing time from stroke onset to scan.
Collapse
Affiliation(s)
- Steven R Messé
- Department of Neurology, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA.
| | | | | | | | | | | | | |
Collapse
|
14
|
Rivers CS, Wardlaw JM, Armitage PA, Bastin ME, Hand PJ, Dennis MS. Acute Ischemic Stroke Lesion Measurement on Diffusion-weighted Imaging–Important Considerations in Designing Acute Stroke Trials With Magnetic Resonance Imaging. J Stroke Cerebrovasc Dis 2007; 16:64-70. [PMID: 17689396 DOI: 10.1016/j.jstrokecerebrovasdis.2006.11.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 10/30/2006] [Accepted: 11/09/2006] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND In acute ischemic stroke, magnetic resonance diffusion-weighted imaging (DWI) is increasingly used to select patients for inclusion or as a surrogate outcome marker in clinical trials, or in routine practice. Little is known of what factors might affect DWI lesion size measurement. We examined morphologic factors that might affect DWI lesion measurement. METHODS On DWI obtained less than 24 hours after stroke, we categorized lesions according to DWI appearance (solitary or multifocal; well-defined or ill-defined edges), lesion size (</>5 cm(3)), and time to imaging (<6, 6-12, and 12-24 hours). Two observers (senior neuroradiologist; less-experienced imaging neuroscientist) measured all lesions. In 4 representative cases we assessed DWI lesion volume using two apparent diffusion coefficient thresholds (0.55 and 0.65 x 10(-3) mm(2)/s). RESULTS Among 63 patients (33% imaged < 6 hours after stroke), the neuroradiologist measured larger lesion volumes than the imaging neuroscientist (median 4.29 v 3.50 cm(3), respectively, P < .01). Differences between observers were greatest in patients scanned within 6 hours of stroke, in multifocal ill-defined or large lesions (all P < .01). Both apparent diffusion coefficient thresholds underestimated lesion extent and included remote normal tissue, particularly in multifocal ill-defined large lesions. CONCLUSION DWI lesion characteristics influence lesion volume measurement. Large, multifocal, ill-defined DWI lesions obtained in less than 6 hours have the greatest variability. Trials using DWI should account for this in their study design.
Collapse
Affiliation(s)
- Carly S Rivers
- Clinical Trials Research Unit, University of Leeds, Leeds, United Kingdom
| | | | | | | | | | | |
Collapse
|
15
|
Gauvrit JY, Leclerc X, Girot M, Cordonnier C, Sotoares G, Henon H, Pertuzon B, Michelin E, Devos D, Pruvo JP, Leys D. Fluid–attenuated inversion recovery (FLAIR) sequences for the assessment of acute stroke. J Neurol 2005; 253:631-5. [PMID: 16362529 DOI: 10.1007/s00415-005-0075-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Revised: 03/15/2005] [Accepted: 03/21/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND AND PURPOSE Diffusion-weighted magnetic resonance (MR) imaging (DWI), and three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA), are highly sensitive for the early detection of stroke and arterial occlusion. However, only a few studies have evaluated the sensitivity of conventional MR sequences that are usually included in the imaging protocol. The aim of this study was to evaluate interobserver and intertechnique reproducibility of Fluid-Attenuated Inversion Recovery (FLAIR) sequences for the diagnosis of early brain ischemia and arterial occlusion. METHODS Over a 30-month period, brain MR examinations were performed in 34 patients within 12 hours after stroke onset. Imaging protocol included FLAIR sequences, DWI and 3D TOF MRA. Ten observers including radiologists and neurologists, performed separately a visual interpretation of FLAIR images for the detection of brain ischemia and arterial occlusion seen as an arterial high signal. DWI and 3D TOF MRA were used as reference and interpreted independently by two senior radiologists. Interobserver agreement was assessed for image quality, detectability and conspicuity of lesions whereas intertechnique agreement was only judged for lesion detectability. RESULTS On FLAIR sequences, interobserver agreement for the detection of brain ischemia and arterial occlusion was excellent (kappa = 0.81 and 0.87 respectively). The concordance between FLAIR and DWI sequences for the detection of brain ischemia and between FLAIR and 3D TOF MRA for the detection of arterial occlusion were judged as excellent for all observers (kappa = 0.91 and 0.89 respectively). CONCLUSION Although DWI is the most sensitive technique with which to detect acute stroke, FLAIR imaging may also be useful to demonstrate both acute ischemia and arterial occlusion with an excellent interobserver reproducibility.
Collapse
Affiliation(s)
- Jean-Yves Gauvrit
- Service de Neuroradiologie, Hôpital Roger Salengro, Rue Emile Laine, 59037, Lille Cedex, France.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Oppenheim C, Naggara O, Arquizan C, Brami-Zylberberg F, Mas JL, Meder JF, Frédy D. Imagerie de l’ischémie cérébrale dans les premières heures : IRM. ACTA ACUST UNITED AC 2005; 86:1069-78. [PMID: 16227903 DOI: 10.1016/s0221-0363(05)81495-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The advent of new MR techniques such as perfusion and diffusion weighted imaging has revolutionized diagnostic imaging in stroke. In some institutions, MRI is used as the sole screening imaging technique for acute stroke patients. In this document, the authors will review the MR pattern of acute ischemic arterial stroke, highlight the usefulness of MRI for the identification of acute hematomas and stroke like episodes, present the potential use of MRI in the management of acute stroke patients, especially when thrombolysis is contemplated, and discuss the role of MRI for imaging transient ischemic attack.
Collapse
Affiliation(s)
- C Oppenheim
- Département d'Imagerie Morphologique et Fonctionnelle, Centre Hospitalier Sainte-Anne, 1, rue Cabanis, 75014 Paris.
| | | | | | | | | | | | | |
Collapse
|
17
|
Oppenheim C, Naggara O, Hamon M, Gauvrit JY, Rodrigo S, Bienvenu M, Ménégon P, Cosnard G, Meder JF. Imagerie par résonance magnétique de diffusion de l'encéphale chez l'adulte : technique, résultats normaux et pathologiques. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.emcrad.2005.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|