Technical update of Delalande’s hemispherectomy

Introduction: Epilepsy is a common neurological disorder characterized by unprovoked seizures, affecting patients socially, psychologically, economically, and cognitively. When pharmacological treatment is insufficient, surgical intervention becomes necessary. Among hemispherectomy procedures, the most notable are anatomical (classic) and functional approaches, including Rasmussen, Delalande, Villemure, and Schramm. Other techniques described in the literature include cerebral hemicorticectomy, hemispherical deafferentation, transcortical subinsular hemispherectomy, and transopercular hemispherectomy. This study aims to analyze surgical methods and their effects while introducing a modified Delalande procedure and evaluating its efficacy through experiments on postmortem brains. Material and methods: The study used magnifying lenses (4.5x and 2.5x) and microsurgical instruments, funded by a PIBIC-CNPq scholarship. The proposed modification maintains the original disconnections but starts in the pericallosal area, offering a direct view of the corpus callosum. The procedure was tested on two formalin-fixed brains, divided into two groups of six coronal sections. Results were analyzed using the Student’s t-test. Results: The number of pericallosal artery lesions was statistically similar in both procedures. However, the modified technique resulted in a smaller neurosurgical incision. Conclusion: While the risk of pericallosal artery injury remains unchanged, a smaller incision may lead to shorter procedure time, better prognosis, and increased safety for both physician and patient. Further studies with larger samples and additional variables are necessary to fully assess its effectiveness.