MRI-guided stereotactic radiofrequency thermocoagulation for 100 hypothalamic hamartomas

Abstract

OBJECT The aim of this study was to elucidate the invasiveness, effectiveness, and feasibility of MRI-guided stereotactic radiofrequency thermocoagulation (SRT) for hypothalamic hamartoma (HH). METHODS The authors examined the clinical records of 100 consecutive patients (66 male and 34 female) with intractable gelastic seizures (GS) caused by HH, who underwent SRT as a sole surgical treatment between 1997 and 2013. The median duration of follow-up was 3 years (range 1-17 years). Seventy cases involved pediatric patients. Ninety percent of patients also had other types of seizures (non-GS). The maximum diameter of the HHs ranged from 5 to 80 mm (median 15 mm), and 15 of the tumors were giant HHs with a diameter of 30 mm or more. Comorbidities included precocious puberty (33.0%), behavioral disorder (49.0%), and mental retardation (50.0%). RESULTS A total of 140 SRT procedures were performed. There was no adaptive restriction for the giant or the subtype of HH, regardless of any prior history of surgical treatment or comorbidities. Patients in this case series exhibited delayed precocious puberty (9.0%), pituitary dysfunction (2.0%), and weight gain (7.0%), besides the transient hypothalamic symptoms after SRT. Freedom from GS was achieved in 86.0% of patients, freedom from other types of seizures in 78.9%, and freedom from all seizures in 71.0%. Repeat surgeries were not effective for non-GS. Seizure freedom led to disappearance of behavioral disorders and to intellectual improvement. CONCLUSIONS The present SRT procedure is a minimally invasive and highly effective surgical procedure without adaptive limitations. SRT involves only a single surgical procedure appropriate for all forms of epileptogenic HH and should be considered in patients with an early history of GS.

Keywords: DQ = developmental quotient; EEG = electroencephalography; EFP = emotional facial paresis; FIQ = full-scale IQ; GS = gelastic seizures; HH = hypothalamic hamartoma; SISCOM = subtraction ictal SPECT co-registered to MRI; SMA = supplementary motor area; SPECT = single-photon emission computed tomography; SRT = stereotactic radiofrequency thermocoagulation; WAIS = Wechsler Adult Intelligence Scale; WAIS-III = WAIS-Third Edition; WAIS-R = WAIS-Revised; WISC = Wechsler Intelligence Scale for Children; WISC-III = WISC-Third Edition; WISC-R = WISC-Revised; epilepsy; epileptic encephalopathy; gelastic seizure; hypothalamic hamartoma; outcome; stereotactic radiofrequency thermocoagulation; surgical treatment.