Abstracts

Rationale: This study aimed at identifying outcomes with respect to seizures, morbidity and mortality in adult patients with hypothalamic hamartomas (HH) undergoing resective surgery or gamma knife radiosurgery to treat intractable epilepsy associated with HH.Methods: Adult patients undergoing surgical treatment for epilepsy related to hypothalamic hamartomas were evaluated at a single center for complications and outcome which were prospectively monitored with the use of a proprietary database. Preintervention and postintervention data of patients aged 18 or older and with at least one year of follow-up were analyzed with specific attention to seizure control, hormonal status, memory and behavioral abnormalities, and death. Results: 40 adult patients were found in the data base (21 women). The median HH volume was 0.71 cm³ and in 70% of patients it was located inside the 3rd ventricle, typically unilaterally, and vertically attached to the hypothalamus (Delalande Type II). Most patients underwent an endoscopic resection (n=26), a smaller amount had a transcallosal or other open resection (n=10), and only 4 patients chose gamma knife (GK) treatment. Twenty-nine percent became seizure free long-term, though a majority of patients (55%) reported at least >90% seizure improvement. Only 3 patients were ultimately able to discontinue anticonvulsants, while most patients were on an average of 2 antiepileptic drugs pre- and postoperatively. The only factor that was significantly correlated with seizure free outcome was absence of mental retardation. HH volume, HH type and amount of resection or disconnection were not correlated to outcome. Memory improved in 52% and behavior in 62% of patients. A total of 4 patients died (10%), 2 immediately after surgery, and 2 others months or years afterwards. None of the patients who died had become seizure free. Persistent post-operative neurological deficits were seen in one patient. Thirty-four percent of patients had permanent hormonal problems and 59% of patients experienced an average weight gain of 12.7 kg.Conclusions: Surgical or gamma knife procedures in adults with HH provided seizure freedom in a third of patients. The only significant favorable prognostic factor was absence of mental retardation. The intervention also tended to improve memory and behavior in the majority of patients. Overall mortality was high at 10%, affecting those patients who had undergone a surgical resection, as opposed to gamma knife, and still had seizures. Other important morbidities were persistent hormonal disturbances and weight gain.