Magnetic resonance (MR) imaging of lumbar spine: use of a shortened protocol for initial investigation of degenerative disease.

PURPOSE To assess the potential use of shortened protocol MRI of lumbar spine in the investigation of degenerative disc disease in Northern Ireland. MATERIALS & METHODS Prospective study of 35 patients having MR imaging of lumbar spine performed during a 12-month period by one consultant radiologist. T1-weighted and T2-weighted sagittal images of lumbar spine were obtained in all cases, as well as T2-weighted axial images. The detection of degenerative disc disease by sagittal T2-weighted imaging alone was compared with the diagnostic information obtained by combined use of axial T2 and sagittal T1 and T2 images. RESULTS In comparison with the full protocol, the shortened protocol had 100% sensitivity and 100% specificity in detecting loss of disc hydration and loss of disc height. In the detection of disc prolapse, the sensitivity was 87% and the specificity was 91% using the shortened protocol. The sensitivity was 35% for detection of thecal sac indentation, and 33% for nerve root encroachment. Therefore, the shortened protocol had high sensitivity and specificity in the detection of disc degeneration and prolapse, but was less sensitive in the detection of nerve root or thecal sac encroachment.