Idiopathic ("congenital") spinal arachnoid diverticula. Clinical diagnosis and surgical results.

We reviewed the clinical records of all the patients examined at the Mayo Clinic who were operated on and found to have arachnoid diverticula of he cervical and thoracolumbar regions of the spinal column. Only patients whose lesion did not have a traumatic cause were selected for a study. There were 21 patients: 20 had been operated on at the Mayo Clinic and 1 was seen 43 years after surgery done elsewhere. The symptoms associated with the thoracolumbar lesions were, in order of decreasing frequency, pain, weakness, gait disorder, sensory symptoms, and sphincter dysfunction. The conditions associated with thoracic arachnoid diverticula included congenital pigmented nevus, diastematomyelia, multiple sclerosis, Marfan's syndrome, and syringomyelia.