Detecting subtle epileptogenic lesions in MRI-negative pediatric epilepsy

Wang W, Lin Y, Wang S, Jones S, Prayson R, Moosa ANV, McBride A, Gonzalez-Martinez J, Bingaman W, Najm I, Alexopoulos A; Pediatric Imaging, Neurocognition and Genetics Study, Wang ZI. Voxel-based morphometric magnetic resonance imaging postprocessing in non-lesional pediatric epilepsy patients using pediatric normal databases. Eur J Neurol. 2019 Jan 27. doi:

10.1111/ene.13916. [Epub ahead of print]

Abstract

BACKGROUND AND PURPOSE:

Pre-surgical evaluation of pediatric patients with drug-resistant focal epilepsy and negative (non-lesional) magnetic resonance imaging (MRI) is particularly challenging. Focal cortical dysplasia (FCD), a frequent pathological substrate in such setting, may be subtle on MRI and evade detection. The aim of this study was to use voxel-based MRI postprocessing to improve the detection of subtle FCD in pediatric surgical candidates.

METHODS:

A consecutive cohort of pediatric patients undergoing pre-surgical evaluation with a negative MRI by visual analysis was included. MRI postprocessing was performed using a voxel-based morphometric analysis program (MAP) on T1-weighted volumetric MRI, with comparison to an age-specific normal pediatric database. The pertinence of MAP-positive areas was confirmed by surgical outcome and pathology.

RESULTS:

A total of 78 patients were included. Forty-four patients (56%) had positive MAP regions. Complete resection of the MAP-positive regions was positively associated with seizure-free outcome compared with the no/partial resection group (P < 0.001). Patients with no/partial resection of the MAP-positive regions had worse seizure outcomes than the MAP-negative group (P = 0.002). The MAP-positive rate was 100%, 77%, 63% and 40% in the 3-5, 5-10, 10-15 and 15-21 year age groups, respectively. MAP-positive rates were 45% in patients with temporal resection and 63% in patients with extratemporal resection. Complete resection of the MAP-positive regions was positively associated with seizure-free outcome in the extratemporal group (P = 0.001) but not in the temporal group (P = 0.070).

CONCLUSION:

Our data suggest the importance of using MRI postprocessing in the pre-surgical evaluation process of pediatric epilepsy patients with apparently normal MRI.

Courtesy of:  https://www.neurologyadvisor.com/topics/pediatric-neurology/detecting-subtle-epileptogenic-lesions-in-mri-negative-pediatric-epilepsy/