부산대학교 도서관

Middle ear myoclonus (MEM) is a rare diagnosis of tinnitus that is presumed secondary to abnormal stapedius or tensor tympani muscle movement. Herein, we describe four cases of MEM with no history of facial palsy. We speculate that tinnitus was caused by tensor tympani muscle contraction, as visible eardrum movement was observed in all four cases. In case 1, eardrum movement was synchronized with forced eyelid closure, which was diagnosed as forceful eyelid closure syndrome. In cases 2, 3, and 4, rhythmic eardrum movement was observed, while putting strength into the ear. In cases 1 and 2, muscular tinnitus became tolerable after behavioral therapy, and the patients declined further treatment, such as medical therapy and surgical tenotomy of the tensor tympani. Thorough history-taking, otoendoscopic examination, and stapedial reflex testing during eye blinking, or putting strength into the ear are recommended when encountering middle ear muscular tinnitus.