Open Radiofrequency Ablation for the Management of Intractable Epilepsy Associated with Sessile Hypothalamic Hamartoma

Abstract

Sessile hypothalamic hamartoma (HH) often causes intractable epilepsy, which is difficult to control even by microsurgical resection and gamma knife surgery (GKS), especially when the hamartoma is intrahypothalamic, large, or irregularly shaped. We successfully applied radiofrequency ablation (RFA) to reduce its epileptogenicity and to disconnect seizure propagation. The patient was a 26-year-old man who presented with refractory epilepsy and severe mental retardation from age 6 months. He had undergone three surgeries yielding partial resection and conventional irradiation treatments. The residual HH was thin and shaped like a bent plate, attached widely to the floor of the third ventricle. He underwent open RFA via the transcallosal sub-choroidal approach under strict image guidance, which resulted in immediate and remarkable seizure remission without complications. This suggests that open RFA is a minimally invasive technique for an irregularly shaped HH that is difficult to treat by other modalities.

Hypothalamic hamartomas. Part 2. Surgical considerations and outcome

“…21,22,24,28 In their most recent paper, Kameyama et al 29 reviewed results from 25 consecutive patients with HH and gelastic seizures who were treated with radiofrequency thermocoagulation. They divided HHs into 3 types based on coronal MRI findings: intrahypothalamic, parahypothalamic, and mixed type.…”

Radiosurgery for hypothalamic hamartomas

“…8 Radiofrequency ablation has also been described. 17,18,25,36 Surgical morbidity is limited overall, especially considering the challenging neural and vascular anatomy surrounding the HH, but includes thalamocapsular infarcts with resulting hemiparesis or hemiplegia, oculomotor palsy, visual field deficits, short-term memory deterioration, hyperphagia, hypothyroidism, and diabetes insipidus. 14,35,44 Complete seizure freedom is difficult to achieve, but in most cases remarkable long-term improvements have been reported with near-total resolution of disabling seizure types and enhanced cognitive and psychosocial abilities.…”

“…9,13,24,35,37,44,45 Substantial seizure improvement following resection, disconnection, or ablation is further proof of the intrinsic epileptogenesis of HHs and the need for a direct approach to produce seizure relief. [2][3][4]8,9,[12][13][14][16][17][18]24,25,28,35,36,[44][45][46][47][48]51,52 The degree of seizure control is linked to the extent of the surgical intervention. Incomplete resection, disconnection, or ablation of the HH can be associated with incomplete seizure control, whereas freedom from seizures may be induced by a more aggressive approach.…”

Clinical characteristics and long-term outcome of surgery for hypothalamic hamartoma in children with refractory epilepsy

“…Other treatment options available for management of HH include open surgical disconnection, endoscopic resection/disconnection, stereotactic radiosurgery, radiofrequency ablation, interstitial brachytherapy, and vagal nerve stimulation. [891011121314151617181920212223242526] Ng et al ., reported the largest series of patients who have undergone endoscopic resection of HH with a seizure freedom of 49% after a minimum period of 1 year follow-up. [12] The improvement in seizures following radiosurgery with gamma knife or linear accelerator follows a temporal sequence with an early favorable response followed by transient worsening and reduction/remission of seizures thereafter.…”

“…[891011121314151617181920212223242526] Microsurgery has the highest success rate and should be the primary treatment option in an era where there is an increasing trend towards combined modalities of treatment.…”