Richard G. Fessler, MD, PhD, FAANS Richard G. Fessler, MD, PhD, FAANS, serves as professor of neurosurgery at the Rush University Medical Center. He is internationally known for his contributions to endoscopic and microendoscopic surgical developments. He has been instrumental in developing many of the current minimally invasive surgical techniques. Dr. Fessler is also well known for his pioneering research into human embryonic spinal cord transplantation for the treatment of spinal cord injury.