Faculty Bibliography

Cell replacement therapy has been evaluated as a regenerative strategy for patients with fixed neurologic deficits after ischemic stroke. Animal models have identified specific cell lines which lead to regeneration and improvement in behavior and motor function after implantation into areas of ischemic injury. This has led to the development of pilot studies in humans, which have mainly investigated the safety and pilot efficacy of such approaches with promising early results. As research in this area progresses, further prospective trials are necessary not only to demonstrate clinical efficacy but also to understand the mechanisms underlying the early positive experiences, to select appropriate patients for cell replacement therapy, and to elucidate the optimal timing and mode of cell delivery.

BACKGROUND: Hypothalamic hamartomas are associated with precocious puberty and chronic epilepsy characterized by gelastic seizures. The seizure disorder is usually refractory to most antiepileptic drugs. Gamma knife surgery has emerged as an alternative to microsurgical removal or radiofrequency ablation to improve seizure control. We present our experience with radiosurgery in 4 patients afflicted by this disorder. METHODS: Using gamma knife radiosurgery, 4 patients with intractable gelastic seizures and complex epilepsy were managed. Patient age varied from 5 to 29 years. The duration of symptoms was 4-28 years. A conformal radiosurgery plan was designed with a mean of 4.25 isocenters to cover the hamartoma at the 50% isodose line. A mean margin dose of 17.5 Gy was used. The clinical outcome was evaluated with the Engel scale. RESULTS: No complication occurred. After a median follow-up of 22 months, 3 patients had shown some improvement, with 2 attaining Engel class II status. CONCLUSION: Gamma knife surgery is a promising alternative to microsurgical removal for patients with refractory epilepsy caused by hypothalamic hamartomas.