Enhancing Lesion Detection With High Field MRI, How Much Can We?

Clinical 7T MRI for Epilepsy: A Retrospective Review of 50 Cases Brian J Burkett, Lily C Wong-Kisiel, Mayur Chalia, Ananya Panda, Karl N Krecke, Steven A Messina, Robert J Witte, Jeffrey W Britton, Benjamin H Brinkmann, Andrew J Fagan, Jason T Little, Theodore J Passe, Robert E Watson, Kirk M Welker. American Journal of Neuroradiology . 2026 Jan;47(1):252-261. doi: 10.3174/ajnr.A8924 Background and purpose: Seven Tesla magnetic resonance imaging (7 T MRI) has specific technical features that are advantageous for epilepsy. This study aims to evaluate whether new potentially epileptogenic abnormalities can be identified on 7 T MRI in patients with epilepsy with negative 3 T MRI findings. Materials and methods: Clinical 7 T epilepsy MRI examinations in patients with prior negative 3 T imaging findings were retrospectively reviewed by 3 neuroradiologists. Their consensus 7 T scan interpretations were reviewed by a neurologist for concordance with EEG findings. Descriptive characteristics of any 7 T MRI abnormalities and their locations were recorded. The clinical and EEG findings in subjects with abnormal 7 T scan findings were compared with those of subjects without a 7 T abnormality. Results: In patients with epilepsy with nonlesional 3 T MRI, new abnormal findings were identified on 7 T MRI in 36% (18/50) of cases. Of the 14 pediatric cases, there were 7 T MRI abnormal findings in 6/14 (42.9%). Across all cases, a total of 21 discrete abnormal findings were identified, including meningoencephaloceles (5/21, 23.8%), cavernous malformations/possible vascular lesions (5/21, 23.8%), focal cortical dysplasia (3/21, 14.3%), gray matter heterotopia (3/21, 14.3%), mesial temporal sclerosis (3/21, 14.3%), 1 indeterminant hippocampal morphology finding (1/21), and 1 case of a diffuse migrational abnormality (1/21). Noninvasive EEG monitoring unit data were concordant with the location of 7 T abnormalities in 60.0% (9/15) of cases with these clinical data available. Participants with generalized seizures (OR, 0.2; 95% CI, 0.041-0.75) and those with multiple seizure types (OR, 0.14; 95% CI, 0.027-0.52) were significantly less likely to have new potentially epileptogenic lesions detected at 7 T. Two 7 T cases with abnormal findings underwent surgical resection with good clinical outcomes (Engel Class IA). Conclusions: In clinical practice, 7 T MRI revealed additional epileptogenic lesions in 36% of nonlesional 3 T MRI cases.