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Value of 3-Dimentional MR Lumbosacral Radiculography in Diagnosis of Symptomatic Chemical radiculitis 2011

General Spine

Woo Mok, Byun, M.D
Han Won, Jang, M.D, Non ASSR Member

Poster

Purpose

To investigate significance of 3-dimentional MR radiculography in diagnosis of symptomatic chemical radiculitis.

Methods & Materials

The study population consisted of 17 patients (age range, 51-72 years; mean ages, 62 years) with annular tear. All patients with annular tear had pain referred to leg. Symptomatic chemical radiculitis was confirmed with provocative CT discography and/or provocative selective nerve root block for agreement of sides and levels. Conventional MR imagings and 3D coronal fast-field echo (FFF) sequence with selective water excitation by using the principles of the selective excitation technique (Proset imaging) were acquired. Morphologic change of ipsilateral symptomatic nerve root caused by chemical radiculitis was compared with those of contralateral nerve root on 3-D MR lumbosacral radiculography. The relationship between morphologic change of symptomatic nerve root caused by chemical radiculitis on 3-D MR lumbosacral radiculography and provocative discography and/or selective nerve root block for confirmation of the radiculopathy was analyzed.

Results

Pain reproduction at contrast leak level during discography (n=4) and selective nerve root injection (n=13) showed concordant pain in all patients. All perianular enhancement caused by chemical radiculitis demonstrated a thick and linear enhancement along margins of annular tears on contrast enhanced axial T1-weighted images with fat suppression. All patients with symptomatic chemical radiculitis showed nerve root swelling in ipsilateral levels and sides on 3-D MR radiculography. The most common nerve root lesion caused by the chemical radiculitis was L5 nerve root (n=13). Swelling of only the exit nerve root was observed in 7 cases. Swelling of the entire segments of the nerve root was seen in 9 cases. One case showed swelling of the transverse nerve root. The most common segments of the nerve root swelling was the exit nerve root (n=16). We suggest that there is relationship between inflammatory perianular enhancement at the extraforaminal or foraminal zones and swelling of the exit nerve root. All patients with symptomatic chemical radiculitis were treated with selective nerve root block. Clinical symptoms were improved within several weeks after selective nerve root block.

Conclusion

All patients with radiculopathy caused by chemical radiculitis showed nerve root swelling on 3-D MR radiculography. We believe that in cases without mechanical nerve root compression caused by disc herniation or stenosis in lumbar spine, nerve root swelling on 3-D MR radiculography in patients with radiculopathy may be relevant in the diagnosis of symptomatic chemical radiculitis.

References/Financial Disclosures

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