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Purpose. To present an advanced ultrasound (US) technique and propose its use as a screening diagnostic tool for temporomandibular joint (TMJ) internal derangement. Materials and Methods. The technique is based on maintaining the US probe parallel to the articular disc, rather than traditional axial and coronal views, with the position described relative to a clock face. Validation was achieved by direct comparison with magnetic resonance imaging (MRI). A total of 61 patients, with age ranging from 13 to 67 years, were prescreened for TMJ pain and internal derangement, underwent US imaging for screening, and MRI evaluation for final diagnosis. Results. 29 of the 61 patients had disc pathology on MRI. US screening produced no false positive results and only 6 false negative results, corresponding to a sensitivity of 79% and specificity of 100%. Half of the false negative cases involved disc pathology with a medial component to the disc displacement. Conclusion. US is both a sensitive and a specific screening tool for TMJ dysfunction when used by an appropriately trained operator, with the exception of medially displaced discs. If TMJ assessment is found to be abnormal, the patient should be referred for MRI, and any patient scheduled for surgery must have the diagnosis confirmed by MRI. If a component of medial disc displacement is suspected, MRI should be performed despite a normal screening US.

A novel technique, ultrasound-guided injection of the temporalis tendon in adults, is described. Ultrasound-guided injection of the temporalis tendon is based on visualization of the temporalis muscle, temporalis tendon, and coronoid process. A practical step-by-step guide to doing the procedure is given. This technique is effective and reproducible. Two patients successfully treated with this technique will be briefly discussed. The anatomic location and size of the temporalis tendon make it mandatory to use ultrasound to ensure precision.