Temporal lobe injury in temporal bone fractures.

OBJECTIVE To determine the incidence of intracranial injury, specifically in the temporal lobe, in patients with longitudinal fractures of the temporal bone. DESIGN Prospective inception cohort. SETTING University of Maryland Division of Otolaryngology-Head and Neck Surgery and the Maryland Shock Trauma Center, Baltimore. PATIENTS Twenty-seven consecutive patients with unilateral or bilateral temporal bone fractures. MAIN OUTCOME MEASURES Evaluation of temporal bone and intracranial trauma using computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS Of the 27 patients enrolled in the study, 12 had the complete battery of MRI, CT, and physical and audiological examinations. In all 12 patients, MRI demonstrated adjacent middle cranial fossa meningeal enhancement. Results of non-contrast-enhanced CT and MRI demonstrated ipsilateral temporal lobe contusions in 6 of the 13 fractures for an overall incidence of 46%. In addition, MRI demonstrated 4 cerebral contusions not seen in the results of non-contrast-enhanced CT. CONCLUSIONS While high-resolution CT remains the criterion standard for evaluation of temporal bone fractures, MRI revealed a higher incidence of related temporal lobe injuries. Magnetic resonance imaging data may be valuable in preoperative evaluation of patients who require surgical intervention through a middle cranial fossa approach to document pre-existing injury and potential morbidity before retraction of the middle cranial fossa dura mater and temporal lobe.