Computed tomography of epidural fibrosis after discectomy: a comparison between symptomatic and asymptomatic patients.

The evaluation of patients with symptoms recurrent after disc surgery is a difficult diagnostic problem. The most common causes are recurrent herniation and postoperative scarring; routine x-ray and myelographic differentiation between herniation and scarring is difficult or impossible. High resolution computed tomography (CT) has shown some results in the evaluation of postoperative patients, but the role of epidural fibrosis in failed back surgery syndrome (FBSS) is not clear. Some knowledge of the "normal" CT physiological healing and scarring after disc surgery is necessary. We scanned 20 asymptomatic operated patients and 20 patients with recurrent sciatic nerve pain after disc surgery who did not have bony stenosis, recurrent disc herniation, or other causes of FBSS. Our observations showed no important differences in the fibrosis demonstrated by CT between symptomatic and asymptomatic patients. The degree and type of fibrosis are not related to recurrent symptoms.