乙状窦沟异常致搏动性耳鸣的影像分析

Imaging findings of pulsatile tinnitus caused by sigmoid sinus abnormalities

目的探讨因乙状窦沟异常引起搏动性耳鸣的影像表现。方法回顾性分析乙状窦沟异常引起搏动性耳鸣的患者15例。均为女性，年龄24～63岁，中位年龄45岁，持续性耳鸣0．5～36．0年，中位持续时间2．0年，其中左侧5例，右侧10例；15例均行颞骨HRCT检查，其中12例行CT脑动脉和（或）脑静脉成像（脑血管CTA／CTV），9例行全脑DSA检查，9例行乙状窦壁骨壁重建术，其中左侧2例，右侧7例。应用配对秩和检验对耳鸣侧和非耳鸣侧乙状窦沟的截面积大小进行比较。结果15例均有单侧乙状窦沟骨壁局部骨质缺损，其中11例发生于前壁，4例发生于前外侧壁，表现为局部骨质缺损。10例乙状窦部分突入乳突蜂房，形成憩室。9例行乙状窦沟骨壁重建术后耳鸣均消失。耳鸣侧乙状窦沟截面积为100．6（41．5～96．2）mm2，非耳鸣侧为77．0（92．1—122．4）mm2，差异有统计学意义（Z=2．158，P=0．031）。结论乙状窦沟局部骨质缺损和乙状窦憩室形成是形成搏动性耳鸣的原因之一，影像检查可以明确诊断。

Objective To study a rare CT finding of pulsatile tinnitus （PT） caused by sigmoid sinus abnormalities. Methods The imaging data of PT caused by sigmoid sinus abnormalities were analyzed retrospectively in 15 patients （ 15 female）. The median age was 45 years （24 to 63 years）. The duration of persistence pulsatile tinnitus was from 0. 5 year to 36. 0 years （ median time, 2. 0 years）. The tinnitus was at left side in 5 patients and right side in 10 patients. Fifteen patients underwent HRCT of the temporal bone. Of them, 12 patients underwent cerebral CT angiography and CT venogram （CTA/CTV） , and 9 patients underwent cerebral digital subtraction angiography （DSA）. Nine patients underwent transmastoid reconstruction surgery of the sigmoid sinus. Of them, the tinnitus was at left side in 2 patients and right side in 7 patients. Paired rank sum test was used to compare the cross-sectional area of the sigmoid sinus of the tinnitus side and normal side. Results On HRCT, focal bony coarse defect is shown in the anterior sigmoid wall in 11 patients and anterolateral sigmoid wall in 4 patients. On CTA/CTV, the sigmoid sinus focally protruded into the adjacent mastoid air cells and formed diverticulum in 10 patients. The pulsatile tinnitus disappeared immediately after transmastoid reconstruction surgery of the sigmoid sinus in all 9 patients. The cross-sectional area of the sigmoid sinus of the tinnitus side was 100. 6 （ 41.5-96. 2 ） mm2, it was 77.0（92. 1-122. 4） mm2 in the nonmal side （Z = 2. 158, P = 0. 031 ）. Conclusion Focal bony defect of the sigmoid wall with sigmoid sinus diverticula is one of the causes which lead to pulsatile tinnitus, which can be easily identified by imaging examination.