Differentiation between Tuberculous and Pyogenic Spondylitis on Gd-enhanced MR Imaging: Focus on the Patterns of Disc Enhancement

Hwang, Seung Bae; Shin, Young Yeol; Lee, Sang Yong; Lee, Jeong Min; Han, Young Min; Chung, Gyung Ho; Kim, Chong Soo

Abstract

PURPOSE: The purpose of this study was to analyze the patterns of intervertebral disc enhancement seen in tuberculous and pyogenic spondylitis, and to evaluate their utility in differentiating between the two groups.
MATERIALS AND METHODS
Magnetic resonance images obtained in 31 consecutive infectious spondylitis patients (43 discs) in whom intervention occurred due to infected vertebral bodies, were retrospectively analysed. Nineteen of the patients had tuberculosis and 12 were infected by pyogenic organisms. After analysis, the patterns of disc enhancement revealed by contrast-enhanced T1-weighted axial and sagittal MR imaging were classified as of four types: Type I, non-enhancing; Type II, enhancement of the peripheral margin of the disc; Type III, enhancement of the peripheral margin and central area adjacent to the cortical vertebral endplate; Type IV, general enhancement and/or destruction of the disc.
RESULTS
There were 19 cases of tuberculous spondylitis involving 28 intervertebral discs, and the enhancement patterns observed were as follows: Type I: n=4, 14%, Type II: n=17, 61%, Type III: n=1, 4%, Type IV: n=6, 21%. Twelve cases of pyogenic spondylitis involved 15 intervertebral discs; the enhancement patterns observed in these cases were as follows: Type I: n=1, 7%, Type II: n=2, 13%, Type III: n=10, 67%, Type IV: n=2, 13%.
CONCLUSION
Careful analysis of the patterns of disc enhancement occurring in infectious spondylitis can be useful for differentiating between the tuberculous and pyogenic varieties of this condition.