Iris Brandlmaier

Condylar erosion and disc displacement: detection with high-resolution ultrasonography

PURPOSE Our goal was to determine the feasibility of high-resolution sonography for the detection of condylar erosion and associated disc displacement at the temporomandibular joint (TMJ) condyle. MATERIALS AND METHODS Forty-eight consecutive patients (96 joints) with TMJ disorders were investigated prospectively using a 12.5-MHz array transducer. Images were assessed for condylar erosion and disc displacements. Sonographic findings were correlated with those of magnetic resonance imaging (MRI). RESULTS At MRI, 18 osseous changes were diagnosed with condylar erosion. Sonographically, 15 of the 18 condylar erosions were diagnosed correctly. Sensitivity, specificity, and accuracy of sonography in the depiction of condylar erosion were 83%, 63%, and 67%, respectively. The positive predictive value was 34%, and the negative predictive value was 94%. Disc displacement without reduction (43 of 96) and disc displacement without reduction concomitant with condylar erosion (16 of 96) were detected with an accuracy of 93% and 80%. CONCLUSION Sonography is an insufficient imaging technique for the detection of condylar erosion. Assessment of disc displacement without reduction may be reliably made with sonography.