Comparison of computed tomography and magnetic resonance imaging for the detection of mandibular condylar osteochondroma*

Abstract

Abstract Objective The purpose of this study was to compare computed tomography (CT) and magnetic resonance imaging (MRI) for the detection of mandibular condylar osteochondroma. Methods Preoperative CT and MRI of 33 patients with unilateral condylar osteochondroma were reviewed. The morphology, location, continuity with the parent bone, cartilage cap, perichondrium of tumors, and changes in soft and hard tissues adjacent to the lesions were investigated by two reviewers. Data were analyzed using McNemar test. A P value < 0.05 was considered significant. Results Among the 33 condylar osteochondromas, 11 were of the diffuse type, 10 were of the sessile type, and 12 were of the pedunculated type. Continuity with the cortex and marrow of the host condyle was observed on both CT and MRI. Both modalities had identical detection rates of surface reconstruction of the temporal bone joint, condylar dislocation, and pseudarthrosis formation. However, MRI showed significantly higher detection rates of the cartilage cap and perichondrium than CT (P < 0.05). Furthermore, MRI showed ipsilateral and contralateral temporo-mandibular joint (TMJ) disc displacement in 4 cases and 6 cases, respectively, and ipsilateral and contralateral TMJ effusion in 20 cases and 14 cases, respectively. Conclusion CT can intuitively display the morphology and spatial location of condylar osteochondromas through three-dimensional reconstruction. MRI may be superior to CT in the detection of cartilage cap, perichondrium of the condylar osteochondroma, and changes in the TMJ and adjacent soft tissues.