Bussières R, Portmann D, Noyon P
Hôtel Dieu de Québec, Service ORL, Canada.
Rev Laryngol Otol Rhinol (Bord). 2003;124(4):259-64.
The diagnosis of perilymphatic fistula (PLF) is difficult since no single clinical situation gives the diagnosis for sure. The goal of this study is to clarify the clinical situations where you must suspect a PLF.
Retrospective study of 20 patients that had an exploratory tympanotomy with a PLF confirmed peroperatively. An analysis of the symptoms, signs and complementary exams was done. The surgical findings and the postoperative evolution were noted.
100% of patients reported a hearing loss, 80% vertigo, 70% a tinnitus and 35% equilibrium problems. Every patient had an etiological event to explain the PLF (trauma 85%), stapedotomy (10%), other ear surgeries. Five patients had a positive fistula or Vasalva test. All patients except one had an hearing loss on the audiogram (sensorineural, mixte or conductive). 50% had a CT scan, 70% of which were abnormal. A VNG was done on 3 patients. The sites of the PLF were as follows: 90% oval window, 5% round window and 5% both windows. The hearing got better or was stabilised in 95% of patients after the operation. 64% saw an improvement of their tinnitus and 87% of their vertigo.
The diagnosis of PLF is difficult and a high index of suspicion is mandatory. One must look for an etiologic situation to explain the PLF. The audiogram is almost always modified, a mixte hearing loss being common due to the high incidence of ossicular trauma associated with PLF. The clinical clinical situations where you must suspect a PLF were identified as follows: An old trauma, a recent trauma, a history of otologic surgery particularly on the stapes and a preexisting hearing loss that aggravates. A diagnosis scale to evaluate the risk of PLF, based on clinical situations, physical exam and complementary exams was done to help the clinician in the evaluation of PLF.
由于没有单一的临床情况能明确诊断外淋巴瘘（PLF），所以其诊断较为困难。本研究的目的是明确必须怀疑存在外淋巴瘘的临床情况。
对20例行探查性鼓室切开术且术中确诊为外淋巴瘘的患者进行回顾性研究。分析其症状、体征及辅助检查情况。记录手术所见及术后病情演变。
100%的患者有听力损失，80%有眩晕，70%有耳鸣，35%有平衡问题。每位患者都有一个可解释外淋巴瘘的病因事件（85%为外伤，10%为镫骨手术，其他耳部手术）。5例患者瘘管试验或瓦尔萨尔瓦试验呈阳性。除1例患者外，所有患者听力图均显示有听力损失（感音神经性、混合性或传导性）。50%的患者进行了CT扫描，其中70%结果异常。3例患者进行了视频眼震图检查。外淋巴瘘的部位如下：90%位于卵圆窗，5%位于圆窗，5%位于双侧窗口。95%的患者术后听力改善或稳定。64%的患者耳鸣改善，87%的患者眩晕改善。
外淋巴瘘的诊断困难，必须保持高度怀疑指数。必须寻找能解释外淋巴瘘的病因情况。听力图几乎总会有改变，由于与外淋巴瘘相关的听骨链外伤发生率高，混合性听力损失很常见。必须怀疑存在外淋巴瘘的临床情况如下：陈旧性外伤、近期外伤、耳科手术史（尤其是镫骨手术）以及原有听力损失加重。基于临床情况、体格检查和辅助检查制定了一个评估外淋巴瘘风险的诊断量表，以帮助临床医生评估外淋巴瘘。
