Fernández A O
Am J Otol. 1983 Apr;4(4):312-4.
Objective tinnitus is a rather rare condition that may be due to myoclonus of certain muscles, such as the palate, or to arteriovenous communications, either congenital or acquired. In cases of palatal myoclonus the diagnosis of the causative factor is not always easy, but the use of tympanometry, EMG, and EEG may help in establishing the diagnosis. In cases of arteriovenous communications a pulse synchronous tinnitus is present. It may be temporarily obliterated by applying pressure over the mastoid area or over the carotid artery on the affected side. Audiometric and tympanometric studies are not diagnostic, and very careful angiographic studies are necessary because routine tests may not show the lesion. The case presented suggests another etiologic possibility for vascular objective tinnitus: a stenosis of certain branches of the external carotid artery. The treatment for myoclonic causes of objective tinnitus has been for the most part unsatisfactory, whether it be medical or surgical. On the other hand, surgical treatment of arteriovenous communications results in complete amelioration of signs and symptoms--hence the necessity for an accurate diagnosis.
客观性耳鸣是一种较为罕见的病症，可能是由某些肌肉（如软腭）的肌阵挛引起，也可能是由先天性或后天性动静脉交通所致。对于腭肌阵挛病例，病因的诊断并不总是容易的，但鼓室导抗图、肌电图和脑电图的应用可能有助于确诊。对于动静脉交通病例，会出现与脉搏同步的耳鸣。通过对患侧乳突区或颈动脉施加压力，耳鸣可能会暂时消失。听力测定和鼓室导抗图检查并无诊断价值，需要进行非常仔细的血管造影研究，因为常规检查可能无法显示病变。所呈现的病例提示了血管性客观性耳鸣的另一种病因可能性：颈外动脉某些分支的狭窄。对于客观性耳鸣的肌阵挛病因，无论是药物治疗还是手术治疗，在很大程度上都不尽人意。另一方面，动静脉交通的手术治疗可使体征和症状完全改善——因此准确诊断很有必要。
