Nam E-C, Lewis R, Nakajima H H, Merchant S N, Levine R A
Department of Otolaryngology, School of Medicine, Kangwon National University, Chunchon, South Korea.
J Laryngol Otol. 2010 Mar;124(3):333-5. doi: 10.1017/S0022215109991241. Epub 2009 Sep 29.
Superior semicircular canal dehiscence affects the auditory and vestibular systems due to a partial defect in the canal's bony wall. In most cases, sound- and pressure-induced vertigo are present, and are sometimes accompanied by pulse-synchronous tinnitus.
We describe a 50-year-old man with superior semicircular canal dehiscence whose only complaints were head rotation induced tinnitus and autophony. Head rotation in the plane of the right semicircular canal with an angular velocity exceeding 600 degrees/second repeatedly induced a 'cricket' sound in the patient's right ear. High resolution temporal bone computed tomography changes, and an elevated umbo velocity, supported the diagnosis of superior semicircular canal dehiscence.
In addition to pulse-synchronous or continuous tinnitus, head rotation induced tinnitus can be the only presenting symptom of superior semicircular canal dehiscence without vestibular complaints. We suggest that, in our patient, the bony defect of the superior semicircular canal ('third window') might have enhanced the flow of inner ear fluid, possibly producing tinnitus.
由于上半规管骨壁存在部分缺损,上半规管裂会影响听觉和前庭系统。在大多数情况下,会出现声音和压力诱发的眩晕,有时还伴有与脉搏同步的耳鸣。
我们描述了一名患有上半规管裂的50岁男性,其唯一的主诉是头部旋转诱发的耳鸣和自听过强。当患者右半规管平面内的头部旋转角速度超过600度/秒时,会反复在其右耳诱发“蟋蟀”声。高分辨率颞骨计算机断层扫描结果以及鼓膜脐部速度升高支持了上半规管裂的诊断。
除了与脉搏同步或持续性耳鸣外,头部旋转诱发的耳鸣可能是上半规管裂唯一的症状,而无前庭症状。我们认为,在我们的患者中,上半规管的骨缺损(“第三窗”)可能增强了内耳液体的流动,从而可能产生耳鸣。