Dr. Heiss is Head, Clinical Unit, in the Surgical Neurology Branch, NINDS, at the National Institutes of Health in Bethesda, Maryland and Clinical Professor of Neurosurgery, George Washington University, Washington, DC. He is the Principal Investigator of clinical research protocols that examine the pathophysiology of syringomyelia and the genetics of Chiari I malformation.

An expert in surgery for brain tumors, syringomyelia, and epilepsy, Dr. Heiss has lectured extensively on various topics in neuroscience and neurosurgery, and has published dozens of original research papers, review articles, and abstracts based on his research. He has served on grant review panels for the National Cancer Institute. Dr. Heiss is board certified in neurological surgery by the American Board of Neurological Surgery.