Initial experience with gamma knife surgery for endocrine ophthalmopathy.

OBJECT: The aim of this study was to evaluate both the effectiveness and safety of the treatment of endocrine ophthalmopathy with gamma knife surgery (GKS). METHODS: Five patients were included in a prospective study designed to assess the results of GKS of endocrine ophthalmopathy secondary to Graves disease. All the patients completed a 2-year follow-up period. During this period, the patients were evaluated both clinically and by means of additional methods, including computerized tomography and magnetic resonance imaging studies. The minimum dose delivered to the 50% isodose line was 6.5 Gy in all the patients. In all cases, a clinical improvement was observed. The best effect was seen in symptom regression related to soft-tissue involvement. No treatment-related side effects were detected. CONCLUSIONS: In light of the results obtained the authors consider that GKS may be a safe and effective way to treat endocrine ophthalmopathy.

Neuronal globus pallidus activity in patients with generalised dystonia.

We studied 516 globus pallidus neurons in dystonic patients. The firing rate was analysed. We classified the burst activity into tonic, burst, and pause patterns. Mean +/- SD firing rates and tonicity score for internal globus pallidus (GPi) and external globus pallidus (GPe) were 54.6 +/- 28.6; 58.01 +/- 39.1 and 1.18 +/- 0.55; 0.95 +/- 0.43, respectively. Differences in percentage appearance of tonic, burst, or paused neurons were not statistically significant for GPi versus GPe. GPi firing features in dystonic patients were closely similar to those of GPe. This could suggest that the abnormally patterned output from GPi would not result from increased differential inhibitory/excitatory input arising from the direct/indirect pathway but rather be transmitted from GPe, striatum, or either centromedian nucleus.