Abstracts

Three decades of epilepsy surgery performed at Washington University Medical Center have allowed for comparison of seizure reduction rates and complications associated with 3 different hemispherectomy procedures.
Records of all patients who underwent a hemispherectomy procedure at Washington University/St. Louis Children[apos]s Hospital were identified from medical record review. Prior to 1995, patients underwent total hemispherectomy or sub-total hemispherectomy. Beginning in 1995, all patients underwent hemispherotomy. Data were abstracted from medical records using a standerized form. Data abstracted included type of surgery, etiology, pre/post surgery seizure frequency, surgical complications, and motor outcomes. Post-surgical seizure reduction was calculated from the average pre and post-surgical seizure frequencies documented in medical records.
From 1972-2002, 28 children (61% male) underwent a hemispherectomy procedure (53% right hemisphere). Before 1995, 3 patients had a total hemispherectomy and 10 had a subtotal hemispherectomy. Since 1995 only hemispherotomies have been performed (n=15). Patients[apos] ages at surgery ranged from 2 months to 16 years. The identified etiologies were: stroke (12/28, 43%), cortical dysplasia (7/28, 25%), Rasmussen[apos]s syndrome (4/28, 14%), meningoencephalitis (3/28, 11%), Sturge-Weber syndrome (1/28, 4%), and traumatic brain injury (1/28, 4%). The mean patient follow-up time was 3.6 years (range, 0.5-21 years). There was no post-surgical follow-up data for three patients. Sixteen of twenty five patients (64%) were seizure free at last follow-up; 7/25 (28%) had more than a 90% reduction is seizure frequency and 2/25 (8%) had a 50%-90% reduction in seizures after surgery. A summary of post-surgical seizure reduction by surgery type is presented in the Table. Arm/hand use, contralateral to surgery, improved in 8/25 (32%), worsened in 3/25 (12%) and remained unchanged in 14/25 (56%) after surgery. Early postoperative complications (within 1st week) were absent in 5/15 (33%) hemispherotomy cases, 1/10 (10%) sub-total hemispherectomy cases, and 0/3 (0%) of total hemispherectomy cases. Overall, the most common early complications were fever (14/25) and subgaleal fluid collection (7/25). Late post-operative complications ([gt]1 week) were absent in 13/15 (87%) hemispherotomy cases, 5/10 (50%) sub-total hemispherectomy cases, and 2/3 (67%) total hemispherectomy cases. Hydrocephalus, shunt related complications, and precocious puberty were the most common late complications.
Hemispherotomy appears to be as effective in reducing seizures and may have less associated post-operative complications compared to the older surgical procedures. [table1]