耳鼻咽喉科学英文版课件 outer ear disease.ppt

1、OUTER EAR DISEASEMicrotiaAnatomy of auricle*From The Ear comprehensive otologyMicrotia 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

2、 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 MicrotiaMicrotiaIVIIIIII Known causesThalidomide(啶酮)Isotretinoin(异维甲酸)Genetic Risk factorDiabetesEti

3、ologyThe 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 pregnancyEpidemiology Occurs 1 in 7,000 to 8,000 infants Occurs more often in right ears Occurs mor

4、e 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 malformationsSurgery options canal reconstruction Ear canal reconstruction is unnecessary and overcomplicated Very good hearing is possible

5、 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

6、 on auricular reconstruction Dr. Nagata 1985 2 stages procedureHistoryRib Cartilage Graft The ear frame before it is assembledPhoto 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 particle

7、s on the implant.A polyethylene plasticTissue engineeringLong term resultLong term resultPrinciples Hearing testing is first done to determine if the inner ear is intact and hearing is normal External canal to determine if a canal exists, by CT scan. (if a canal is not visible externally) Age The earliest age surgery can be attempted is age 3 for Medpor and 6 for Rib Cartilage Grafts. However a later age recommend, 8-10 when the ear is full adult sizeThanks！