Kennedy Kenneth L., Singh Achint K.
University of Louisville
Un of Texas Health Sci Ctr San Antonio
Cholesteatoma is a misleading term (misnomer) that suggests the presence of "chole" (cholesterol) or "steat" (fat), neither of which are found in these lesions. Coined by Johannes Müller in 1863 to describe a primary tumor of adipose tissue, cholesteatomas are actually noncancerous but can be potentially destructive growths. They typically develop in the pneumatized portions of the temporal bone, such as the middle ear and mastoid, and are rarely found in the ear canal. Cholesteatoma can be either an epidermoid cyst arising from aberrant embryonic nests in the congenital form or a benign, expanding tumor of keratinizing squamous epithelium that may cause locoregional inflammation, infection, and destruction. The exact origins of congenital cholesteatomas remain uncertain, with no universally accepted theory. Acquired cholesteatomas, further categorized into primary-acquired and secondary-acquired, will be the focus of this activity. Primary-acquired cholesteatomas develop due to pressure changes in the middle ear that cause tympanic membrane retraction, often as a result of eustachian tube dysfunction following chronic otitis media. This retraction can damage the ossicles and erosion of the tegmen mastoideum. In contrast, secondary-acquired cholesteatomas arise from direct injury to the tympanic membrane, typically caused by infection or trauma. Both types of acquired cholesteatomas present significant challenges in diagnosis, treatment, and management due to their insufficient blood supply. Common signs include progressive hearing loss and persistent foul-smelling otorrhea that is resistant to medical therapy. Acquired cholesteatomas can damage the hearing mechanism, specifically the tympanic membrane and ossicles, disrupt eustachian tube function, erode the tegmen mastoideum, cause dehiscence of the facial nerve, alter vestibular function, and, in rare cases, lead to central nervous system (CNS) complications. Systemic treatments such as antibiotics and steroids are often ineffective. Due to the layering effect of keratinizing squamous debris and drainage, topical treatments, including antibiotics, steroids, or antifungal agents, typically offer only transient or superficial relief.
胆脂瘤是一个容易引起误解的术语（用词不当），它暗示存在“胆”（胆固醇）或“脂”（脂肪），但在这些病变中均未发现。1863年由约翰内斯·米勒创造，用于描述脂肪组织的原发性肿瘤，胆脂瘤实际上是良性的，但可能是具有潜在破坏性的生长物。它们通常发生在颞骨的气化部分，如中耳和乳突，很少见于耳道。胆脂瘤可以是先天性形式下由异常胚胎巢产生的表皮样囊肿，也可以是角质化鳞状上皮的良性、扩展性肿瘤，可能导致局部炎症、感染和破坏。先天性胆脂瘤的确切起源仍不确定，没有普遍接受的理论。获得性胆脂瘤，进一步分为原发性获得性和继发性获得性，将是本活动的重点。原发性获得性胆脂瘤是由于中耳压力变化导致鼓膜内陷而形成的，通常是慢性中耳炎后咽鼓管功能障碍的结果。这种内陷会损害听小骨并导致乳突盖侵蚀。相比之下，继发性获得性胆脂瘤源于鼓膜的直接损伤，通常由感染或外伤引起。由于血液供应不足，这两种类型的获得性胆脂瘤在诊断、治疗和管理方面都面临重大挑战。常见症状包括进行性听力丧失和持续的恶臭耳漏，对药物治疗有抵抗性。获得性胆脂瘤会损害听力机制，特别是鼓膜和听小骨，破坏咽鼓管功能，侵蚀乳突盖，导致面神经裂开，改变前庭功能，在极少数情况下，会导致中枢神经系统（CNS）并发症。抗生素和类固醇等全身治疗通常无效。由于角质化鳞状碎屑和引流的分层效应，包括抗生素、类固醇或抗真菌剂在内的局部治疗通常只能提供短暂或表面的缓解。
