Simultaneous Audio and Cine Magnetic Resonance Imaging of the TMJ

Objectives: Our study reinforces potential for a multi-modal clinical tool to contribute to a comprehensive TMD classification system and establish interventions that can better treat each individual TMJ. We propose that a mechanistic understanding of TMJ sound generation can lead to a greater understanding of disease states and consequently more informed TMD diagnoses and individualized treatments. Therefore our aim was to assess the feasibility of combining two modes of observation, audio and MRI, for quantitative and qualitative inquiries allowing for thorough characterization and treatment of each TMD. To our knowledge, simultaneous recording of joint sounds during cine-MRI of TMJ had never been achieved. Methods: After obtaining IRB approval, we enrolled five volunteers fitting inclusion/exclusion criteria eliciting audible joint sounds during open-close jaw movements. A fiber-optic microphone (FOMRI-III, Optoacoustics, Yehuda Israel) was used to record joint sounds during high-speed cine 3.0-T MRI scan at NYU Langone Health. Subjects were instructed to produce joint sound during MRI. For each scan, Bitmap images were extracted from DICOM series and correlated with corresponding audio data. Results: Our results demonstrate the successful integration of audio and MR imaging for the TMJ. This protocol was shown to be well-tolerated by our subjects. We present a precise correlation of MR images with audible observations. Conclusions: TMJ sounds have been assessed by an array of methodologies. Despite a wealth of data there is little direct observation of anatomic sources of sound production. Our protocol for simultaneous audio/cine-MRI is a viable tool for studying TMJ health and disease. In future studies this protocol may refine our understanding of how TMJ sounds relate to its anatomy, physiology, and pathology. Moreover, by expanding dimensions with which we can assay the health status of a TMJ, we hope to establish a diagnostic aid that more precisely guides surgical and non-surgical decision-making.