Chiari I malformation as a cause of orthostatic intolerance symptoms: a media myth?

There is much interest in a putative relationship between Chiari I malformation and symptoms of orthostatic intolerance. It has been reported at scientific meetings that a number of patients with chronic fatigue syndrome or fibromyalgia have Chiari I malformation, or hindbrain compression in the absence of Chiari, and that they experience improvement after decompression surgery. Many of these patients have symptoms of orthostatic intolerance. A connection between Chiari I malformation and these conditions has been discussed in newspaper articles and on national television programs. Patients have also had access to much information on this topic via the Internet. Unfortunately, the Chiari I malformation and orthostatic intolerance connection is almost entirely unsupported by peer-reviewed literature. The purpose of this article is to provide an objective review of the available information.