학술논문
Diagnostic separation of conventional ⩾50% carotid stenosis and near-occlusion with phase-contrast MRI.
Document Type
Academic Journal
Author
Holmgren M; Department of Clinical Sciences, Neurosciences, Umeå University, Umeå, Sweden.; Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden.; Henze A; Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden.; Wåhlin A; Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden.; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.; Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden.; Eklund A; Department of Radiation Sciences, Biomedical Engineering, Umeå University, Umeå, Sweden.; Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden.; Fox AJ; Sunnybrook Health Science Center, University of Toronto, Toronto, ON, Canada.; Johansson E; Department of Clinical Sciences, Neurosciences, Umeå University, Umeå, Sweden.; Wallenberg Center for Molecular Medicine, Umeå University, Umeå, Sweden.; Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden.
Source
Publisher: SAGE Publications Ltd Country of Publication: England NLM ID: 101688446 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 2396-9881 (Electronic) Linking ISSN: 23969873 NLM ISO Abbreviation: Eur Stroke J Subsets: MEDLINE
Subject
Language
English
Abstract
Introduction: The aim of this study was to assess sensitivity, specificity and interrater reliability of phase-contrast MRI (PC-MRI) for diagnosing carotid near-occlusion.
Patients and Methods: Prospective cross-sectional study conducted between 2018 and 2021. We included participants with suspected 50%-100% carotid stenosis on at least one side, all were examined with CT angiography (CTA) and PC-MRI and both ICAs were analyzed. Degree of stenosis on CTA was the reference test. PC-MRI-based blood flow rates in extracranial ICA and intracranial cerebral arteries were assessed. ICA-cerebral blood flow (CBF) ratio was defined as ICA divided by sum of both ICAs and Basilar artery.
Results: We included 136 participants. The ICAs were 102 < 50% stenosis, 88 conventional ⩾50% stenosis (31 with ⩾70%), 49 near-occlusion, 12 occlusions, 20 unclear cause of small distal ICA on CTA and one excluded. For separation of near-occlusion and conventional stenoses, ICA flow rate and ICA-CBF ratio had the highest area under the curve (AUC; 0.98-0.99) for near-occlusion. ICA-CBF ratio ⩽0.225 was 90% (45/49) sensitive and 99% (188/190) specific for near-occlusion. Inter-rater reliability for this threshold was excellent (kappa 0.98). Specificity was 94% (29/31) for cases with ⩾70% stenosis. PC-MRI had modest performance for separating <50% and conventional ⩾50% stenosis (highest AUC 0.74), and eight (16%) of near-occlusions were not distinguishable from occlusion (no visible flow).
Conclusion: ICA-CBF ratio ⩽0.225 on PC-MRI is an accurate and reliable method to separate conventional ⩾50% stenosis and near-occlusion that is feasible for routine use. PC-MRI should be considered further as a potential standard method for near-occlusion detection, to be used side-by-side with established modalities as PC-MRI cannot separate other degrees of stenosis.
Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Patients and Methods: Prospective cross-sectional study conducted between 2018 and 2021. We included participants with suspected 50%-100% carotid stenosis on at least one side, all were examined with CT angiography (CTA) and PC-MRI and both ICAs were analyzed. Degree of stenosis on CTA was the reference test. PC-MRI-based blood flow rates in extracranial ICA and intracranial cerebral arteries were assessed. ICA-cerebral blood flow (CBF) ratio was defined as ICA divided by sum of both ICAs and Basilar artery.
Results: We included 136 participants. The ICAs were 102 < 50% stenosis, 88 conventional ⩾50% stenosis (31 with ⩾70%), 49 near-occlusion, 12 occlusions, 20 unclear cause of small distal ICA on CTA and one excluded. For separation of near-occlusion and conventional stenoses, ICA flow rate and ICA-CBF ratio had the highest area under the curve (AUC; 0.98-0.99) for near-occlusion. ICA-CBF ratio ⩽0.225 was 90% (45/49) sensitive and 99% (188/190) specific for near-occlusion. Inter-rater reliability for this threshold was excellent (kappa 0.98). Specificity was 94% (29/31) for cases with ⩾70% stenosis. PC-MRI had modest performance for separating <50% and conventional ⩾50% stenosis (highest AUC 0.74), and eight (16%) of near-occlusions were not distinguishable from occlusion (no visible flow).
Conclusion: ICA-CBF ratio ⩽0.225 on PC-MRI is an accurate and reliable method to separate conventional ⩾50% stenosis and near-occlusion that is feasible for routine use. PC-MRI should be considered further as a potential standard method for near-occlusion detection, to be used side-by-side with established modalities as PC-MRI cannot separate other degrees of stenosis.
Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.