An association between imaging and acute posttraumatic ear bleeding with trismus.

OBJECTIVE

Computed tomography findings for each of 94 patients with unilateral ear bleeding and trismus correlated with either comminuted temporal bone fracture (26 cases) or bilateral temporomandibular joint fracture (68 cases).

METHODS

Ninety-four patients with post-traumatic unilateral ear bleeding and 10 asymptomatic adults underwent coronal computed tomography examinations of their temporomandibular joints. Of these, 26 patients with intact temporomandibular joints underwent axial computed tomography of the temporal bones. For 23 of the 94 symptomatic patients, computed tomography was the final imaging procedure; for the other 71 symptomatic patients, it was the first imaging procedure. Quantifications of the radiation dose and the per-patient cost of imaging were performed. Measurement of the maximal mandibular movements in vertical and horizontal directions was performed clinically in the 10 asymptomatic adult control subjects and in the 94 patients with trismus and ear bleeding.

RESULTS

Ten control subjects had maximal opening values of 40 mm or more, and horizontal movement exceeded 24 mm. In 68 symptomatic patients, coronal computed tomography demonstrated bilateral fracture: there was bilateral high condylar fracture in 35 patients, and there was ipsilateral to the bleeding high condylar fracture with contralateral subcondylar fracture dislocation in 33 patients. Axial computed tomography scans in 26 symptomatic patients with intact temporomandibular joints demonstrated comminuted petrous bone fracture ipsilateral to the ear bleeding.

CONCLUSIONS

Patients with post-traumatic ear bleeding associated with trismus should first be evaluated by computed tomography. Any other initial procedure doubles the radiation dose as well as the cost of the imaging.