Images below require Macromedia's Flash Player to view

Neuroradiology Case of the Week

Case 179

Uchendu Azodo, MD and Per-Lennart Westesson, MD, PhD, DDS

Clinical Presentation: A 5-year-old patient presents for CT evaluation of right-sided temporal bone anomaly.

Radiological Findings:

Diagnosis: Congenital aural atresia

Discussion: Congenital aural atresia is a term used to refer to a spectrum of ear deformities present at birth. These are representative to some degree of failure of development of the external ear or auditory canal.  The malformation often involves the tympanic membrane, ossicles, and middle ear to varying degrees, but is rarely associated with inner ear abnormalities. In order to restore the sound conducting system, radiographic delineation of anatomies is necessary. 
   The main anatomic deformity in congenital absence of the external auditory canal is that the canal never developed. The severity of the deformity varies from mild to severe.
     Congenital aural atresia occurs in about 1 in 15,000 live births. Unilateral is more common than bilateral. The etiology is unknown. Not all patients with congenital aural atresia are candidates for surgical correction. Approximately 60% can be treated surgically. 

References:

1. De la Cruz A, Chandraseckhar SS. Congenital malformation of the temporal bone. In, Otologic Surgery, DE Brackman, Ed., WB Saunders, Philadelphia; 1994.
2. Kamerer DB. Congenital and acquired atresia of the external auditory canal. In, Operative Otolaryngology, Head and Neck Surgery, EN Meyers, Ed., WB Saunders, Philadelphia; 1997.
3. Schuknecht HF. Congenital aural atresia. Laryngoscope. 1989 Sep;99(9):908-17. [Medline]
4. Lambert PR. Congenital aural atresia. In, Head & Neck Surgery - Otolaryngology, 2nd Ed, BJ Bailey, Ed. Lippincott-Raven, Philadelphia; 1998.
5. Bauer GP, Wiet RJ, Zappia JJ. Congenital aural atresia. Laryngoscope. 1994 Oct;104(10):1219-24. [Medline]
6. Jahrsdoerfer RA, Yeakley JW, Aguilar EA, Cole RR, Gray LC. Grading system for the selection of patients with congenital aural atresia. Am J Otol. 1992 Jan;13(1):6-12. [Medline]
7. Yeakley JW, Jahrsdoerfer RA. CT evaluation of congenital aural atresia: what the radiologist and surgeon need to know. J Comput Assist Tomogr. 1996 Sep-Oct;20(5):724-31. [Medline]
8. Trigg DJ, Applebaum EL. Indications for the surgical repair of unilateral aural atresia in children. Am J Otol. 1998 Sep;19(5):679-84; discussion 684-6. [Medline]
9. Lambert PR. Congenital aural atresia: stability of surgical results. Laryngoscope. 1998 Dec;108(12):1801-5. [Medline]
10. Jahrsdoerfer RA, Lambert PR. Facial nerve injury in congenital aural atresia surgery. Am J Otol. 1998 May;19(3):283-7. [Medline]
11. Lambert PR, De la Cruz A, Choo DI. Management of the unilateral atretic ear. In, Controversies in Otolaryngology, ML Pensak, Ed., Thieme, New York; 2001.
12. Ng M, Horlbeck D. Aural Atresia. http://www.emedicine.com/ent/topic141.htm