International Journal of Pediatrics Table 4: Comparison of surgical techniques, seizure outcomes, and complications. Author and year Technique No. of patients Schramm et al. [10] Villemure and Daniel [9] Delalande et al. [11] Thomas et al.; our series Transylvian hemispherectomy Peri-insular hemispherotomy Vertical hemispherotomy Peri-insular hemispherotomy and posterior quadrantectomy 20 43 83 34 Engels Class1 outcome 88% 90% 74% 91.1% Complications Mortality 5% Infection 5% Mortality 2% Hydrocephalus 2% Hemorrhage 5% Mortality 4% Hydrocephalus 16% Mortality 0% Hydrocephalus 2.9% Pseudomeningocele 5.8% 5 Mean followup (years) 3.8 9 4.4 2.5 (a) (b) Figure 5: (a) T2W Axial Flair MRI Image of a patient with right hemimegalencephaly showing an enlarged right hemisphere with thickened cortical mantle, distorted ventricular anatomy, and widened gyri, (b) intraoperative photograph. (a) (b) Figure 6: (a) T1W Axial gadolinium MRI image of a patient with Sturge Weber disease showing left hemispheric leptomeningeal angiomatosis, (b) intraoperative photograph.