上海交通大学耳鼻咽喉科学英文版课件 outer ear disease.pptVIP

* OUTER EAR DISEASE Microtia Anatomy of auricle *From The Ear comprehensive otology Microtia Grade I: A slightly small ear with identifiable structures and a small but present external ear canal Grade II: A partial or hemi-ear with a closed off or stenotic external ear canal producing a conductive hearing loss Grade III: Absence of the external ear with a small peanut vestige structure and an absence of the external ear canal and ear drum Grade IV: Absence of the total ear or anotia Classification of Microtia Microtia IV I III II Known causes Thalidomide(啶酮) Isotretinoin(异维甲酸) Genetic Risk factor Diabetes Etiology The occurrence of microtia is usually a random, sporadic event, and it is important for the parents to understand that the deformity was not caused by anything the mother did before or during the pregnancy Epidemiology Occurs 1 in 7,000 to 8,000 infants Occurs more often in right ears Occurs more often in males Higher incidence in Hispanics and Asians than in blacks and whites Fewer than 15% with positive family history Associated with other congenital malformations Surgery options canal reconstruction Ear canal reconstruction is unnecessary and overcomplicated Very good hearing is possible with modern hearing aids auricular reconstruction Rib Cartilage Graft Reconstruction a polyethylene plastic implant Microtia reconstruction Dr. Tanzer 1959 1st article on auricular reconstruction with autogenous rib cartilage, 6 stages procedure Dr. Brent 1974 4 stages procedure, foremost authority on auricular reconstruction Dr. Nagata 1985 2 stages procedure History Rib Cartilage Graft The ear frame before it is assembled Photo of implant components on a surgical drape. Caution: The porous implant material should not be placed on surgical drapes or other fibrous material that may shed particles on the implant. A polyethylene plastic Tissue engineering Long term result Long term result Principles Hearing testing is first done to determine if the inner