“Within a minute” detection of focal cortical dysplasia

Abstract

Purpose To evaluate a MRI postprocessing tool for the enhanced and rapid detection of focal cortical dysplasia (FCD). Methods MP2RAGE sequences of 40 consecutive, so far MRI-negative patients and of 32 healthy controls were morphometrically analyzed to highlight typical FCD features. The resulting morphometric maps served as input for an artificial neural network generating a FCD probability map. The FCD probability map was inversely normalized, co-registered to the MPRAGE2 sequence, and re-transferred into the PACS system. Co-registered images were scrolled through “within a minute” to determine whether a FCD was present or not. Results Fifteen FCD, three subcortical band heterotopias (SBH), and one periventricular nodular heterotopia were identified. Of those, four FCD and one SBH were only detected by MRI postprocessing while one FCD and one focal polymicrogryia were missed, respectively. False-positive results occurred in 21 patients and 22 healthy controls. However, true positive cluster volumes were significantly larger than volumes of false-positive clusters (p < 0.001). The area under the curve of the receiver operating curve was 0.851 with a cut-off volume of 0.05 ml best indicating a FCD. Conclusion Automated MRI postprocessing and presentation of co-registered output maps in the PACS allowed for rapid (i.e., “within a minute”) identification of FCDs in our clinical setting. The presence of false-positive findings currently requires a careful comparison of postprocessing results with conventional MR images but may be reduced in the future using a neural network better adapted to MP2RAGE images.

MRI of focal cortical dysplasia

“…Thus, it is recommended to use a postprocessing tool for every patient with a drug-resistant focal epilepsy. Among the different tools, the VBM tool morphometric analysis program (MAP) is most widely used tool; it has been integrated in standard presurgical workflows of over 60 epilepsy centers in 22 different countries [35,55,64]. The MAP tool has independently been validated for its clinical benefits against expert neuroradiological assessments [26, 34, 54,] with potential impact on further, also invasive presurgical patient management [34,57].…”

“…Surface-based (SBM) tools at least theoretically allow for a better analysis of the cortical layers itself; however, the superiority to VBM has not been shown yet [20-30, 51, 65]. Multiple standalone tools also processing multiple including quantitative sequences are currently being developed [25,27,28,30,31,47,52,64,66]. Which postprocessing tool will prevail is at the end also a matter of availability and ease of use [64].…”

“…Multiple standalone tools also processing multiple including quantitative sequences are currently being developed [25,27,28,30,31,47,52,64,66]. Which postprocessing tool will prevail is at the end also a matter of availability and ease of use [64].…”

Prognostic analysis in children with focal cortical dysplasia II undergoing epilepsy surgery: Clinical and radiological factors

“…MRI-negative is a misnomer that comprises patients without an MRI lesion or with a subtle MRI lesion but being overlooked ( 8 ). Although high-field imaging and postprocessing techniques have dramatically improved the detection rate of FCD, there are still limitations in the artifacts ( 22 ), the high false positive rate outcome ( 23 ), and clinical application promotion. Due to the preferential occurrence of dysmorphic neurons in deep cortical layers ( 24 , 25 ), MRI abnormalities are mostly displayed close to the gray matter–white matter interface.…”

Preoperative Detection of Subtle Focal Cortical Dysplasia in Children by Combined Arterial Spin Labeling, Voxel-Based Morphometry, Electroencephalography-Synchronized Functional MRI, Resting-State Regional Homogeneity, and 18F-fluorodeoxyglucose Positron Emission Tomography

“…However, other cases had irrelevant clusters, highlighting the need for EEG-guided analysis of these data, in combination with other imaging techniques. 15 Several reports have studied the efficiency of VBM in adult FCD 9 but very few in pediatric patients. [16][17][18] Processing techniques are highly diverse, giving variable results that are useful but often insufficient for a clinical workflow.…”