Incidental findings during head and neck MRI screening in 1717 patients with temporomandibular disorders

Objective Magnetic resonance imaging (MRI) plays an important role in the evaluation of temporomandibular disorders (TMDs). At our institution, we perform additional head and neck screening using head coils when performing MRI screening of the temporomandibular joint (TMJ) to detect lesions in areas other than the TMJ (lesions discovered by chance, or incidental findings; IFs) and to conduct a diagnosis of exclusion. The objective of this study was to determine the number and frequency of IFs detected during head and neck screening, according to sites and diseases. Materials and methods The study evaluated 1717 patients with clinically suspected TMDs who underwent MRI of the TMJ. IFs were assessed on horizontal sections of images of the craniofacial region obtained by the short tau inversion recovery imaging technique. Results The patients undergoing MRI of the TMJ comprised 433 males and 1284 females. Among the patients, at least one IF was detected on images in 461 patients. The most common IF site was the maxillary sinus. Based on diagnostic imaging, there were 21 IFs (1.2%) associated with TMD symptoms, or for which an association with TMD symptoms could not be ruled out. Conclusions Combination of conventional MRI imaging of the TMJ with craniofacial MRI screening may allow detection of lesions other than TMDs, thereby confirming the usefulness of MRI. Detection of IFs may require development of different therapeutic strategies than those for TMDs.