Temporal bone fractures and complications: Correlation between high-resolution computed tomography and audiography

Abstract

Acute head trauma in the emergency room is managed primarily by the trauma surgeon or neurosurgeon. Temporal bone fractures with the complications of hearing loss and facial nerve paralysis may not be promptly evaluated. The otolaryngologist may not be consulted until late in the hospitalization. Traditionally, longitudinal fractures have been associated with conductive hearing loss and transverse fractures with sensorineural hearing loss. The purpose of this study was to correlate the type of fracture with audiometric findings of hearing loss. We also studied the incidence of facial nerve paralysis and its associated fracture types.

A total of 2906 head trauma patients admitted to the emergency room from March 1994 to May 1996 were reviewed. All patients had a head computed tomographic (CT) examination. High-resolution CT of the temporal bones was performed in patients suspected of having a temporal bone fracture. Temporal bone fractures were found in 48 patients (2%) and were classified as longitudinal, transverse, or mixed. Audiometry was performed by the Department of Otolaryngology in 23 of the patients with temporal bone fractures. Patients with longitudinal fractures had conductive hearing loss in 43% and sensorineural loss in 23%. Of patients with transverse fractures, 57% had conductive hearing loss, and 29% had sensorineural loss. Facial nerve paralysis was found in 11% of patients. Patients with transverse fractures were found to have facial paralysis in 2 of 11 (18%), whereas those with longitudinal fractures had paralysis in 3 of 36 (8%).

Our study found conductive hearing loss to be more frequent than sensorineural loss in patients with longitudinal and transverse fractures. This finding differs from traditional associations. We found the fracture orientation as defined by high-resolution CT scanning of the temporal bones to be a poor predictor of associated hearing loss. Facial nerve paralysis can occur with both transverse and longitudinal fractures, and extension of fractures to the geniculate ganglion should be sought on high-resolution CT scans of the temporal bone. The emergency room physicians should be notified of this potential complication.