Introduction: Patients afflicted with Low-grade gliomas (LGG) frequently suffer fromepileptic seizures. The mechanisms of epileptogenesis in these patients remain poorly understood.
Methods: We present the first study to use a voxel-wise quantitative lesion analysis to investigate the spatial correlation between tumor location and seizure susceptibility. We prospectively collected the medical records and MR images of 410 LGG patients. The data set is divided into a discovery set (n=231) and a validation set (n=179) based on the hositals where the patients were treated. Voxel-based lesion–symptom correlative analysis was performed to determine whether tumor location associate with seizure risk based on the specific type of seizure (simple partial seizure, complex partial, and seizures with secondary generalization).
Results: For all seizure types, increased seizure risks were identified for low-grade gliomas involving the left frontal pre-motor area. By seizure type, the LGGs involving the left inferior frontal gyrus were associated with increased risk of simple partial seizures. LGG involving the right temporal-insular region are associated with increased risk of complex partial seizure. LGG involving the left superior frontal lobe were more likely associated with seizures that secondarily generalize. These correlations were consistently observed in both the discovery and the validation data sets.
Conclusions: Our quantitative neuroimaging analyses support the notion that anatomical location of LGG is contributing factor in tumor-related epilepsy.
Patient Care: Seizure prophylaxis for LGG located in regions of high seizure risk warrants consideration.
Learning Objectives: Understand the anatomic basis for seizure risk in patients
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