Diagnostic accuracy of panoramic radiograph and MRI for detecting signs of TMJ degenerative joint disease

Abstract

Background: To determine the diagnostic accuracy of panoramic radiograph and magnetic resonance imaging (MRI) for detection of signs of temporomandibular joint (TMJ) degenerative joint disease (DJD). Methods: Panoramic radiographs, bilateral TMJ MRI and bilateral TMJ computed tomography (CT) were performed on 705 subjects. Three calibrated board-certified radiologists blinded to the subjects’ clinical findings interpreted all images. Assessment of diagnostic accuracy of panoramic radiographs and MRI for detecting signs of DJD was compared to the reference-standard diagnoses derived from the CTs. DJD was defined by the presence of subcortical cyst, surface erosion, osteophyte or generalized sclerosis. Target sensitivity and specificity were > 70% and > 95%, respectively. Results: For panoramic radiographs, sensitivity and specificity were: subcortical cysts - 14%, 100% respectively; erosion - 20%, 100% respectively; osteophyte - 12%, 100% respectively and generalized sclerosis - 33%, 100%, respectively. For MRI, sensitivity and specificity were: subcortical cysts - 32%, 100% respectively; erosion - 35%, 99% respectively; osteophyte 71%, 98% respectively and generalized sclerosis 50%, 100% respectively. For diagnosis of signs of DJD based on panoramic radiographs, radiologists’ inter-examiner reliability was slight (k=0.16), moderate (k=0.47) when using MRI and substantial with CT images (k=0.71). Conclusions: Panoramic radiographs and MRI had below target sensitivity but above target specificity in detecting all CT-depicted signs of DJD with the exception of detection of MRI-depicted osteophytes, which had adequate diagnostic accuracy. Practical Implications: Use of CT to diagnosis signs of TMJ DJD is recommended to address the false negatives that can occur with panoramic radiographs and MRI.