The objective of this study is to evaluate whether microvascular decompression (MVD) of the right lateral medulla is efficacious in improving glycemic control and ameliorating the underlying pathophysiology in Tye II Diabetes Mellitus (Type II DM). To appraise efficacy of MVD, clinical parameters of glucose control, postpradial insulin secretory capacity and glucose homeostasis and fasting rates of hepatic glucose production will be determined before and after MVD in 10 patients with Type II DM. The 10 research volunteers will be recruited based on a diagnosis of Type II DM and pre-operative magnetic resonance imaging evidence of vascular compression of the right lateral medulla. This protocol will be part of an overall research plan designed to test the hypothesis that vascular compression of the right lateral medulla contributes to the pathophysiology of Type II DM and that relief of medullary compression can alleviate this pathophysiology and improve glucose homeostasis.