Vertical parasagittal hemispherotomy:: Surgical procedures and clinical long-term outcomes in a population of 83 children

OBJECTIVE: Hemispherotomy techniques have been developed to reduce complication rates and achieve the best possible seizure control. We present the results of our pediatric patients who underwent vertical parasagittal hemispherotomy and evaluate the safety and global long-term outcome of this technique. METHODS: Eighty-three patients underwent vertical parasagittal hemispherotomy by the same neurosurgeon (OD) between 1990 and 2000. We reviewed all patients between 2001 and 2003 for a standard global evaluation. The general principle is to achieve, through a posterior frontal cortical window, the same line of disconnection as performed with the classic hemispherectomy, while leaving the majority of the hemisphere intact along with its afferent and efferent vascular supply. RESULTS: Seventy-four percent of the patients were seizure-free; among them, 77% were seizure-free without further drug treatment. Twelve percent rarely had seizures (Engel Class II) and 14% continued to have seizures (Engel Class III or IV). The results varied according to the etiology, but this variation was not statistically significant. The early postoperative course was uneventful for 94% of the children, and shunt placement was necessary in 15%. We found a correlation between the preoperative delay and the Vineland Adaptive Behavior score: children with a longer duration of seizures had lower performances. CONCLUSION: Vertical parasagittal hemispherotomy is an effective surgical technique for hemispheric disconnection. It allows complete disconnection of the hemisphere through a cortical window with good results in terms of seizure outcome and a comparably low complication rate.