title: Type 2 diabetes mellitus: A central nervous system etiology.
abstract: BACKGROUND
  Insulin resistance (hyperinsulinemia) is said to be the signal event and causal in the development of type 2 diabetes mellitus. Pulsatile arterial compression of the right anterolateral medulla oblongata is associated with autonomic dysfunction, including "driving" the pancreas, which increases insulin resistance causing type 2 diabetes mellitus. In this prospective study, we hypothesize that decompressing the right cranial nerve X and medulla will result in better glycemic control in patients with type 2 diabetes mellitus.
  
  
  METHODS
  Ten patients underwent retromastoid craniectomy with microvascular decompression for type 2 diabetes mellitus. Patients were followed for 12 months postoperatively by blood glucose monitoring and studies of glycemic control, pancreatic function and insulin metabolism. No changes in diet, weight or activity level were permitted during the course of the project.
  
  
  RESULTS
  Seven of the 10 patients who received microvascular decompression for type 2 diabetes mellitus showed significant improvement in their glucose control. This was noted by measurement of diabetes markers and decrease of diabetes medication dosages. One patient was completely off diabetes medication, while attaining euglucemia. The other 3 patients did not improve in their glucose control. The body mass index of these 3 patients was higher (mean, 34.4) than those with better outcomes (mean, 27.9).
  
  
  CONCLUSIONS
  Arterial compression of the right anterolateral medulla appears to be a factor in the etiology of type 2 diabetes mellitus. Microvascular decompression may be an effective treatment for non-obese type 2 diabetes mellitus patients.
authors.affiliation: Department of Neurosurgery, Allegheny General Hospital, 420 East North Avenue, Suite 302.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Jannetta
authors.forename: Lynn H
authors.initials: LH
authors.lastname: Fletcher
authors.forename: Peter M
authors.initials: PM
authors.lastname: Grondziowski
authors.forename: Kenneth F
authors.initials: KF
authors.lastname: Casey
authors.forename: Raymond F
authors.initials: RF
authors.lastname: Sekula