Effect of Vagus Nerve Stimulation in Post-Traumatic Epilepsy and Failed Epilepsy Surgery : Preliminary Report

OBJECTIVE: Vagus nerve stimulation (VNS) has been used in epilepsy patients refractory to standard medical treatments and unsuitable candidates for resective or disconnective surgery. In this study, we investigated the efficacy of VNS to patients who had refractory result to epilepsy surgery and patients with post-traumatic epilepsy. METHODS: We analyzed the effect of VNS in 11 patients who had undergone previous epilepsy surgery and patients with intractable post-traumatic epilepsy associated with brain injury. All patients underwent VNS implantation between October 2005 and December 2006. RESULTS: We evaluated seizure frequency before and after implantation of VNS and maximum follow up period was 24 months. In the first 6 months, 11 patients showed an average of 74.3% seizure reduction. After 12 months, 10 patients showed 85.2% seizure reduction. Eighteen months after implantation, 9 patients showed 92.4% seizure reduction and 7 patients showed 97.2% seizure reduction after 24 months. Six patients were seizure-free at this time. CONCLUSION: We conclude that the VNS is a helpful treatment modality in patients with surgically refractory epilepsy and in patients with post-traumatic epilepsy due to severe brain injury.

Endovascular Treatment for a Persistent Trigeminal Artery Aneurysm Presenting as Isolated Sixth Nerve Palsy / 신경중재치료의학

The trigeminal artery is the most common persistent carotid-basilar anastomotic channel observed in adult life, and its occurrence probably represents a defect in cerebrovascular development. It can be associated with other congenital abnormalities such as cerebral aneurysms, but only rarely do aneurysms of the persistent trigeminal artery itself arise. Endovascular treatment of these aneurysms has not been attempted so much. We report a case of endovascular treatment for a persistent trigeminal artery aneurysm causing isolated sixth nerve palsy.

Pituitary Irradiation by Gamma Knife in Intractable Cancer Pain

OBJECTIVE: Cancer pain has been treated by gamma knife radiosurgery(GKS), targeted to the pituitary gland-stalk, as an alternative new pain control method. The purpose of this study is to prove the efficacy and the safety of this treatment. METHODS: Seven patients with intractable cancer pain underwent pituitary gland-stalk irradiation by gamma knife. Selections for patient inclusion in this treatment protocol were no other effective pain treatment options, general condition rated as greater than 40 on Karnofsky Performance Scale, and pain relief by morphine though not satisfactory. The target was the junction between the pituitary stalk and the neurohypophysis. The maximum dose was 150~160Gy with one isocenter in 8mm collimator or two isocenters in 4mm collimator keeping the radiation dose to the optic nerve less than 8Gy. RESULTS: In all seven cases, the significant pain reduction was obtained during immediate post-GKS period without serious complications except one patient who developed transient hypopituitarism and diabetes insipidus. Pain relief was observed within several days, and this effect was prolonged for a quite long time. At a follow up of 1.5 to 13 months, pain recurred in two patients and no hormonal and visual dysfunctions were observed. CONCLUSION: Despite insufficient experience, the efficacy and the safety of GKS for intractable cancer pain were demonstrated in seven patients. This treatment has the potential to ameliorate cancer pain, and GKS will play a more important role in the treatment of intractable pain.