Radiology, Vol 182, 59-64, Copyright © 1992 by Radiological Society of North America

ARTICLES

Contrast-enhanced MR imaging performed after successful lumbar disk surgery: prospective study

SD Boden, DO Davis, TS Dina, CP Parker, S O'Malley, JL Sunner and SW Wiesel
Department of Orthopaedic Surgery, George Washington University Medical Center, Washington, DC 20037.

A prospective study was undertaken to establish the normal spectrum and timing of gadolinium-enhanced magnetic resonance (MR) imaging findings in 15 patients who had resolution of symptoms after successful lumbar disk surgery. Enhancement of the facet joints (in 88% of disk levels) and paraspinal muscles (100%) decreased gradually after surgery. Enhancement of the decompressed nerve root tracked proximally toward the conus medullaris in 62% at 3 weeks and was absent in all by 6 months postoperatively. Areas of intermediate signal intensity with peripheral enhancement and mass effect were seen on T1-weighted images at the site of the original disk herniation in 38% at 3 weeks and 12% at 3 months, despite complete relief of leg pain. These results reveal that even in successfully treated (asymptomatic) patients, residual mass effect on the neural elements may frequently simulate a recurrent or residual disk fragment. There is an orderly progression of imaging changes during the first 6 months after lumbar surgery that limits the interpretation of MR examinations during that period.

This article has been cited by other articles:

				M. N. Brant-Zawadzki, S. C. Dennis, G. F. Gade, and M. P. Weinstein Low Back Pain Radiology, November 1, 2000; 217(2): 321 - 330. [Abstract] [Full Text]

				S. D. BODEN Current Concepts Review - The Use of Radiographic Imaging Studies in the Evaluation of Patients Who Have Degenerative Disorders of the Lumbar Spine J. Bone Joint Surg. Am., January 1, 1996; 78(1): 114 - 24. [Full Text]