Differentiation between symptomatic and asymptomatic extraforaminal stenosis in lumbosacral transitional vertebra: role of three-dimensional magnetic resonance lumbosacral radiculography.
OBJECTIVE
To investigate the role of lumbosacral radiculography using 3-dimentional (3D) magnetic resonance (MR) rendering for diagnostic information of symptomatic extraforaminal stenosis in lumbosacral transitional vertebra.


METHODS
The study population consisted of 18 patients with symptomatic (n = 10) and asymptomatic extraforaminal stenosis (n = 8) in lumbosacral transitional vertebra. Each patient underwent 3D coronal fast-field echo sequences with selective water excitation using the principles of the selective excitation technique (Proset imaging). Morphologic changes of the L5 nerve roots at the symptomatic and asymptomatic extraforaminal stenosis were evaluated on 3D MR rendered images of the lumbosacral spine.


RESULTS
Ten cases with symptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. On 3D MR lumbosacral radiculography, indentation of the L5 nerve roots was found in two cases, while swelling of the nerve roots was seen in eight cases at the exiting nerve root. Eight cases with asymptomatic extraforaminal stenosis showed hyperplasia and degenerative osteophytes of the sacral ala and/or osteophytes at the lateral margin of the L5 body. Based on 3D MR lumbosacral radiculography, indentation or swelling of the L5 nerve roots was not found in any cases with asymptomatic extraforaminal stenosis.


CONCLUSIONS
Results from 3D MR lumbosacral radiculography Indicate the indentation or swelling of the L5 nerve root in symptomatic extraforaminal stenosis. Based on these findings, 3D MR radiculography may be helpful in the diagnosis of the symptomatic extraforaminal stenosis with lumbosacral transitional vertebra.
Department of Diagnostic Radiology, College of Medicine, Yeungnam University, Daegu 705-717, Korea. wmbyun@yu.ac.kr
Woo Mok
WM
Byun
Jae Woon
JW
Kim
Jae Kyo
JK
Lee
D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008161:Lumbosacral Region / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000175:diagnosis* / Q000473:pathology; D054850:Osteophyte / Q000473:pathology; D013130:Spinal Stenosis / Q000175:diagnosis* / Q000473:pathology
D003287:Contrast Media