Evaluation of the “False Positive Internal Joint Derangement” in Sonography by Using MRI

Abstract

Statement of Problem: Today, the most precise method for TMJ soft tissue imaging is MRI. But, due to high cost and complexities of this procedure, its application to all patients is neither possible, nor logical. So, many physicians are forced to treat their involved patients in TMJ dysfunction, without complete information about disc situation, based only on the results of clinical exams and evidences of conventional radiography of TMJ hard tissues.Purpose: The aim of this study is to evaluate the accuracy of the high resolution-Ultra sonography (HR-US) in TMJ disc displacement detection. This is done via the evaluation of the “false positive internal joint derangement” in sonography by using MRI.Materials and Method: MRI imaging of 16 TMJs of 10 patients, which in clinical exams were diagnosed as ADD (Anterior Disc Displacement) cases, was confirmed by sonography. The results of sonography compared with those of MRI were tabulated (table 1). The final results presented descriptively.Results: In this study, all cases of ADD diagnosed in sonography, were confirmed by MRI too.Conclusion: HR-US can be used in TMJ diagnosis and treatment planning as a reliable technique for imaging of disc in this joint.Key words: MRI, HR-US, TMJ, Disc, ADD