ИСТИНА

Hypothalamic hamartoma (HH) is a dysplastic lesion fused with the hypothalamus and manifest clinically by epilepsy, precocious puberty and behavioral disorders. Up to 50% of patients become free of seizures after surgery, but various complications occur in 1/4 of them. Radiofrequency thermocoagulation, laser interstitial thermal therapy, and stereotactic radiosurgery (SRS) are alternative treatment options. OBJECTIVE: To define indications for SRS in patients with HH and to clarify the irradiation parameters. METHODS: Twenty-two patients with HH and epilepsy underwent SRS at the Moscow Gamma-knife Center with sufficient FU-data available for retrospective outcome evaluation in 19 of them. The median age at the time of treatment was 11.5 years (1.3 - 25.8) and the diameter of irradiated lesion ranged between 5.5 to 40.9 mm. In 8 cases (36%), the lesion volume exceeded 3 cm3. The average prescribed dose was 18 Gy +/- 2.0, the average prescribed isodose – 48% +/- 4.2. The median FU was 14.8 months (3.4 - 96.1). RESULTS: Three patients were free of every seizures at the last check (Engel IA - 15.8%). One patient (5.3%) improved dramatically after treatment with compete resolution of generalized convulsions and experiencing only rare emotional seizures (Engel IB). Eleven patients (57.8%) reported a marked decrease in frequency of seizures. The severity and frequency of seizures did not change in 4 patients (21.1%). The best results were achieved in cases with an average target dose above 20-22 Gy, the minimal target dose more than 7-10 Gy, at least 70-80% of the lesion volume covered by prescribed dose, and in patients with HH almost total covered by dose above 12 Gy. None of the patients had any complications after SRS. CONCLUSIONS: SRS is safe and free of treatment related neurological, endocrine or visual disturbances. Careful patient selection for SRS makes it an effective option to treat epilepsy in patients with HH. The best candidates for SRS are children with seizure age at onset older than 1 year, the lesion volume less than 3 cm3, and if the area of HH-fusion with the hypothalamus does not exceed 150 mm2.