Medical Student Carle Illinois College of Medicine, Minnesota, United States
Introduction: We sought to compare the efficacy of 7 Tesla (7T) versus 1.5T and 3T in the diagnosis and management of cerebrovascular disease. Given the 2017 FDA approval of 7T MRI for clinical use, it is urgently necessary to establish the cerebrovascular conditions and diagnostic questions best addressed by 7T compared to lower field systems at 1.5T and 3T.
Methods: A systematic search was performed on PubMed and Web of Science with a pre-planned search strategy, yielding 369 unique reports. Articles were included if direct comparisons of 1.5/3T versus 7T imaging for cerebrovascular pathologies were reported. For meta-analysis, we pooled standardized mean differences (SMD) between studies reporting the number of lesions detected between 1.5T or 3T and 7T MRI. This review is written in accordance with PRISMA guidelines.
Results: In 19 studies consisting of 381 patients, atherosclerosis, arteriovenous malformation (AVM), and aneurysm were the most examined pathologies. Three studies reported the mean number and variance of lesions per patient comparing low-field and 7T imaging. 7T MRI showed a pooled effect of 3.24 more lesions (SMD, 95% CI: -0.69-7.16, p = 0.11) using a random-effects model. Thirteen studies provided quantitative metrics that indicated superior diagnostic capability of 7T over 1.5T or 3T.
Conclusion : 7T MRI studies provided better resolution and image quality than comparable scans at lower field strengths. This review highlights how 7T provides better diagnostic value in the management aneurysms and AVM because it more clearly delineates abnormal vascular networks and can detect a greater number of lesions. However, this advantage does not reach statistical significance. Therefore, more studies with larger sample sizes are needed to establish 7T systems as the preferred imaging tool to assess the extent and location of cerebrovascular disease.
