CT and MRI findings of temporal bone anomaly in patients with tinnitus

Abstract

Objective To study high resolution CT (HRCT) and MRI findings of temporal bone anomaly in patients with tinnitus and identify the optimal examination method in the detection of the anomaly. Methods The HRCT and MRI data were analyzed retrospectively in 1015 patients including 145 patients with pulsatile tinnitus (PT) and 870 patients with nonpulsatile tinnitus (NPT). The positive rates of HRCT and MRI in the identification of temporal bone anomaly were analyzed and the efficiency of various examination methods was compared in revealing the anomaly. Data were tested by Chi-square test analysis. Results Among 1015 patients, anomaly was seen in 767 cases (75.57%). High jugular bulb was found in 414 patients, accounting for 40. 79%. Sigmoid sinus anomaly was detected in 387 patients (38. 13%), while otitis media was found in 148 cases (14. 58%), and low middle cranial fossa in 70 cases (6. 90%). The positive rate of HRCT in the detection of high jugular bulb was 54. 89% (365/665), which was significantly higher than those of other methods (P ＜ 0. 05). The positive rate of enhanced HRCT in showing sigmoid sinus anomaly was 73.68% (56/76), which was significantly higher than those of other methods(P ＜0. 05). Sigmoid sinus anomaly was the most frequent finding in patients with PT, accounting for 66. 21% (96/145). The incidence of sigmoid sinus anomaly was higher in PT than in NPT (291/870,33.45% ;χ2 =56. 537 ,P ＜0. 01). The fast imaging employing steady-state acquisition (FIESTA) sequence was the best examination method in displaying the vessel within the internal auditory canal (42/42,100%).Conclusions High jugular bulb and sigmoid sinus anomaly were the most frequent abnormal findings of temporal bone in patients with tinnitus. Enhanced HRCT was the choice of modality in patients with PT.Plain HRCT was recommended for NPT. FIESTA sequence was the best in the evaluation of the vessel within the internal auditory canal. Key words: Tinnitus; Temporal bone; Tomography, X-ray computed; Magnetic resonance imaging