Brea Beatriz, Roldán Fidalgo Amaya
Servicio de Neurorradiología, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, España.
Acta Otorrinolaringol Esp. 2013 Jan-Feb;64(1):6-11. doi: 10.1016/j.otorri.2012.06.004. Epub 2012 Aug 15.
Benign lesions of the external auditory canal (EAC) are an infrequent cause of temporal bone CT scan requests. We are not usually well versed in the different pathologies located in the EAC, perhaps because it is "only" a conduit and the relevant anatomical structures are located in the middle and inner ear. Our objective was to improve knowledge of this structure by reviewing the different benign conditions found in this location.
We reviewed the CT studies from 2 years (January 2010 through January 2012), selecting those containing lesions in the EAC. To complement this, due to the importance of these lesions, these medical histories were then analysed considering the presentation and otoscopic examination findings.
The lesions were classified according to their diagnoses: exostosis, osteoma, cholesteatoma, keratosis obturans, haemangioma, non-neoplastic aural polyp, first branchial cyst and dermatologic disease (malignant external otitis). The presence of EAC occupation in the otological examination and chronic otorrhea as the symptom of presentation were the most relevant exploratory and clinical findings.
Benign EAC lesions are an uncommon and seldom studied cause of temporal bone CT scan requests. Knowing the most relevant clinical and radiological findings is necessary for their proper diagnosis.
外耳道（EAC）良性病变是颞骨CT扫描申请的罕见原因。我们通常并不十分熟悉EAC中存在的不同病理情况，这可能是因为它“仅仅”是一个管道，而相关解剖结构位于中耳和内耳。我们的目的是通过回顾在该部位发现的不同良性疾病来增进对这一结构的了解。
我们回顾了2年（2010年1月至2012年1月）的CT研究，选择那些在外耳道有病变的病例。为了补充这一点，由于这些病变的重要性，随后根据临床表现和耳镜检查结果对这些病历进行了分析。
根据诊断结果对病变进行分类：外生骨疣、骨瘤、胆脂瘤、闭塞性角化病、血管瘤、非肿瘤性耳息肉、第一鳃裂囊肿和皮肤病（恶性外耳道炎）。耳科检查中外耳道占位的存在以及慢性耳漏作为临床表现是最相关的探索性和临床发现。
外耳道良性病变是颞骨CT扫描申请的罕见且很少被研究的原因。了解最相关的临床和放射学发现对于其正确诊断是必要的。
