Computed tomography findings of chronic osteomyelitis involving the mandible: correlation to histopathological findings

OBJECTIVES: The aim of this study is to discuss the pathological course of chronic osteomyelitis of the mandible by investigating a correlation between CT and histopathological findings and to argue the usefulness of CT examination in the evaluation of mandibular chronic osteomyelitis. METHODS: CT images obtained between 1997 and 2004 of 62 lesions in 60 patients with chronic osteomyelitis involving the mandible were reviewed retrospectively. CT images obtained at initial examination or pre-operative evaluation were reviewed and CT findings of affected bone were classified into three patterns: bone-defect pattern, frosted-glass pattern and compact-bone pattern. In 7 of 62 lesions, CT images and histopathological specimens were selected to obtain a side-by-side comparison in order to clarify what histopathological features reflect those three patterns of CT findings. Additionally, the correlations among the three patterns in the course of mandibular chronic osteomyelitis were also assessed. RESULTS: The areas of bone-defect pattern, frosted-glass pattern and compact-bone pattern observed on CT images were revealed to indicate fibre-rich granulation tissue, new formation of bony trabeculae and thickening of bony trabeculae on histopathological findings, respectively. CONCLUSIONS: It was considered that these three patterns are significant in the evaluation of the process of the course of chronic osteomyelitis. We advocate that CT is useful to grasp the complex pathological conditions of chronic mandibular osteomyelitis.