Tumor dose inhomogeneity can be used as an important and convenient parameter to evaluate mMLC LINAC-based SRS plans. Sharp dose fall off in the normal tissue is achieved with sufficiently high tumor dose inhomogeneity. By adjusting beam margins, a homogeneity index of approximately 1.3 would provide best conformity for the authors' SRS system.

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Meningeal melanocytoma is a rare pigmented tumor originating from the melanocytes that generally occurs in the posterior fossa and the spinal cord. Although it is known as a relatively benign tumor, some recurrences have been reported. We report two cases of spinal meningeal melanocytoma with immunohistochemical and ultrastructural studies. In addition, we include a summary of published cases since the first case of Limas and Tio in 1972.

Objective:To describe the neuropathologic findings and clinical course of 2 patients who underwent temporal lobectomy for medically refractive epilepsy and were later found to have high anti–glutamic acid decarboxylase (GAD) concentrations.Methods:Small case series.Results:Neuropathologic examination of both patients revealed International League Against Epilepsy (ILAE) type 3 hippocampal sclerosis. Following surgery, both developed signs and symptoms of stiff person syndrome and later cerebellar ataxia. Laboratory studies demonstrated high concentrations of anti-GAD antibodies in both patients.Conclusions:These cases suggest that ILAE type 3 hippocampal sclerosis may be immunologically related to and may exist as part of a broader anti-GAD–related neurologic syndrome in some instances.