Transcallosal Resection of Hypothalamic Hamartoma for Intractable Epilepsy

Abstract

Summary:Purpose: To present the results of transcallosal surgical resection of hypothalamic hamartoma (HH) in 26 patients with refractory epilepsy in a prospective outcome study.Methods: Patients with refractory epilepsy symptomatic to HH were referred for surgical resection of their HH (mean age, 10.0 years; range, 2.1-24.2 years). A transcallosal, interforniceal approach was used to remove and/or disconnect the hamartoma. Volumetry was obtained on pre-and postoperative brain MRI scans to determine percentage of resection. Outcome assessment included determination of postoperative seizure frequencies in comparison to baseline and the incidence of postoperative complications. Postoperative changes in cognitive and behavioral functioning, in comparison to baseline, were elicited by parental report.Results: The average postoperative follow-up interval was 20.3 months (range, 13-28 months). Fourteen (54%) patients were completely seizure free, and nine (35%) had at least a 90% improvement in total seizure frequency. Parents reported postoperative improvement in behavior in 23 (88%) patients and in cognition in 17 (65%) patients. Transient postoperative memory disturbance was seen in 15 (58%) patients, but persisted in only two (8%). Two (8%) patients had persisting endocrine disturbance requiring hormone replacement therapy (diabetes insipidus and hypothyroidism in one each). With univariate analysis, the likelihood of a seizure-free outcome correlated with younger age, shorter lifetime duration of epilepsy, smaller preoperative HH volume, and 100% HH resection.Conclusions: Refractory epilepsy associated with HH can be safely and effectively treated with surgical resection by a transcallosal, interforniceal approach. Short-term memory deficits appear to be transient for most patients, and family perception of the impact of surgery on cognitive and behavioral domains is favorable. Complete resection yields the best result.

The evolution of treatment for hypothalamic hamartoma: a personal odyssey

“…Abla et al 1 performed the orbitozygomatic approach in 10 patients and reported 40% of patients were seizure-free, 40% attained > 50% seizure reduction, and 66% attained seizure freedom when there was a total or near-total excision of the HH. Ng et al 23 found that 100% resection correlated with better seizure control.…”

“…These results were later replicated at the Barrow Neurological Institute. 23 In 2002, Palmini et al 27 reported on 13 patients who underwent surgery for HHs from 3 centers, 12 using a frontotemporal approach and 1 using an endoscopic approach. Delalande and Fohlen 9 reported on 17 patients in 2003 who underwent surgery for HH (14 transsylvian and 9 endoscopic approaches).…”

Magnetic resonance imaging–guided laser interstitial thermal therapy for previously treated hypothalamic hamartomas

“…1,16 Transcallosal interforniceal approaches have been reported as well, 7,22 although some groups have noted that older patients can experience memory impairment following this approach. 15 Transventricular endoscopic resection and disconnections have also been performed when feasible. 21,24 Stereotactic radiosurgery offers the possibility of minimal trauma to the hypothalamus but lower rates of long-term seizure control.…”

Deep brain stimulation for the treatment of drug-refractory epilepsy in a patient with a hypothalamic hamartoma

“…27,40 Disconnection by transventricular or transcallosal endoscopic approach has a good outcome and fewer complications than resective surgery. 1,8,14,24 There is also strong evidence that radiofrequency and Gamma Knife surgery may lead to complete seizure control with limited morbidity. 3,9,15,16,29,31,33,40,42 The Grenoble group hypothesizes that seizures arising from the HH spread to the cortex through the mamillothalamo-cingulate tract.…”