Dural ectasia is a widening or ballooning of the dural sac surrounding the spinal cord usually at the lumbosacral level. It is one of the major manifestations of Marfan syndrome. It may cause low back pain, headaches and neurological signs such as weakness and loss of bowel and bladder function, but in many patients it is asymptomatic. It is also a cause of posterior vertebral scalloping present in radiographs in patients who are diagnosed with neurofibromatosis.
Dural ectasia may also manifest in Ehlers-Danlos Syndrome, Neurofibromatosis, Marfan Syndrome, cauda equina syndrome in ankylosing spondylitis, and other disorders that afflict connective tissue.