Voxel‐based morphometric magnetic resonance imaging (MRI) postprocessing in MRI‐negative epilepsies
ObjectiveIn the presurgical workup of magnetic resonance imaging (MRI)‐negative (MRI− or “nonlesional”) pharmacoresistant focal epilepsy (PFE) patients, discovering a previously undetected lesion can drastically change the evaluation and likely improve surgical outcome. Our study utilizes a voxel‐based MRI postprocessing technique, implemented in a morphometric analysis program (MAP), to facilitate detection of subtle abnormalities in a consecutive cohort of MRI− surgical candidates.
MethodsIncluded in this retrospective study was a consecutive cohort of 150 MRI− surgical patients. MAP was performed on T1‐weighted MRI, with comparison to a scanner‐specific normal database. Review and analysis of MAP were performed blinded to patients' clinical information. The pertinence of MAP+ areas was confirmed by surgical outcome and pathology.
ResultsMAP showed a 43% positive rate, sensitivity of 0.9, and specificity of 0.67. Overall, patients with the MAP+ region completely resected had the best seizure outcomes, followed by the MAP− patients, and patients who had no/partial resection of the MAP+ region had the worst outcome (p < 0.001). Subgroup analysis revealed that visually identified subtle findings are more likely correct if also MAP+. False‐positive rate in 52 normal controls was 2%. Surgical pathology of the resected MAP+ areas contained mainly non–balloon‐cell focal cortical dysplasia (FCD). Multiple MAP+ regions were present in 7% of patients....
Source: Annals of Neurology - Category: Neurology Authors: Z. Irene Wang, Stephen E. Jones, Zeenat Jaisani, Imad M. Najm, Richard A. Prayson, Richard C. Burgess, Balu Krishnan, Aleksandar Ristic, Chong H. Wong, William Bingaman, Jorge A. Gonzalez‐Martinez, Andreas V. Alexopoulos Tags: Research Article Source Type: research