Differentiation between Tuberculous Spondylitis and Pyogenic Spondylitis on MR Imaging

OBJECTIVE The objective of this study was to compare the magnetic resonance (MR) imaging of tuberculous spondylitis with pyogenic spondylitis. METHODS MR images of the spines of 41 patients with infectious spondylitis at our institution over 8-years of period were retrospectively reviewed. Eighteen patients with infective spondylitis were excluded because their results on the marrow biopsy and culture were negative. MR imaging findings in 6 patients with tuberculous spondylitis (3 male, 3 female) were compared with those of 17 patients (10 male, 7 female) with pyogenic spondylitis. RESULTS Two MR imaging findings were statiscally significant in differentiating the tuberculous spondylitis from pyogenic spondylitis: a well defined paraspinal abnormal signal and a thin and smooth abscess wall. There were no significant differences in the following MR imaging findings: paraspinal abscess or intraosseous abscess, subligamentous spread to three or more vertebra, involvement of multiple vertebra, hyperintense signal on T2-weighted images, heterogenous low signal on T1-weighted images, involvement of posterior element, epidural extension, involvement of intervertebral disk, disk space narrowing, rim enhancement of the abscess, skip lesion, and endplate destruction. CONCLUSION MR imaging is an appropriate modality for differentiation of tuberculous spondylitis from pyogenic spondylitis.