Saturday, September 15, 2007

Constricted Ear Deformity

The constricted ear includes a spectrum of auricular anomalies in which the rim of the ear appears as if it has been tightened with a purse-string. Terms often used to describe this deformity include log ear, lidded helix, cup ear, canoe ear, and cockle shell ear. Significant constriction of the ear constitutes fewer than 10% of all ear anomalies in the United States, but very mild forms are so frequent as to be considered a normal variant. Scapha compression and mild helical lidding appear in 2-5% of a randomly examined clinic population. The incidence is 10-15% in blacks. (these photos from last reference article)
The four features of the completely developed anomaly are
  • Lidding of the helix
  • Compression or narrowing of the scapha and fossa triangularis with decreased ear size
  • Protrusion of the ear
  • Low ear position

A lop ear is a malformed auricle in which the characteristic major deformity is an acute downward folding and/or deficiency of the helix and scapha, usually at the level of the tuberculum auriculae (Darwin's tubercle). The deformity is associated with a malformed antihelix, usually at the superior crus.

A cup ear is essentially a malformed, protruding ear combining characteristics of both a lop ear and a prominent ear. Typical features are 1) an overdeveloped, deep, cup-shaped concha, 2) a deficient superior part of the helical margin and antihelical crura, and 3) apparently small vertical height. The body of the antihelix is often wider than normal, and whether it is unfolded or fully developed tends to exaggerate the cupping deformity. In some cases the helical margin or helical fold drapes forward and over the scapha like a hood.

Tanzer's Classification of Constricted Ears

Type I--Helical involvement only

Type IIA--Involvement of the helix and scapha, with no supplemental skin needed

Type IIB--Helical and scaphal involvement, with supplemental skin needed at auricular margin

Type III--Extreme cupping deformity with involvment of the helix, scapha, antihelix, and conchal wall (Some, like Cosman, dismiss this group as forms of microtia.)

The goals of surgical correction should include obtaining symmetry and correcting the intra-auricular anatomy. The degree of intervention is based on the severity of the deformity and may range from simple repositioning, soft tissue rearrangement, or manipulation of the cartilage. Correction of Type I involves detaching the folded helix and reattaching it in an upright position. Correction of Type IIA involves adjusting the anterior helix, filleting the deformed helix and scapha, and reconstructing the upper pole of the ear with "banner" flaps of cartilage. Correction of Type IIB involves using a skin flap from the medial surface of the ear and various methods for expanding the ear cartilage. (photos from next to last reference article)

Sometimes surgical correction (with Type I or Type IIA) can be avoided by splinting during the early neonatal period. Good results have been reported in up to 85% of the patients when the treatment is continuous over the entire 4-week period. However, when treatment is partial or discontinuous, only 10% will have good results. Early initiation of treatment has proven to be more effective than later treatment. Strong parental cooperation and close follow-up are also important for success.

References

  • Ear Constriction Deformity and Otoplasty Ear Plastic Surgery--Dr. Michael Bermant's website
  • Non-surgical correction of a congenital lop ear deformity by splinting with Reston foam; Br J Plast Surg. 1982 Apr;35(2):181-2; Kurozumi N, Ono S, Ishida H.
  • Splinting Therapy for Congenital Auricular Deformities with the use of Soft Material; J Perinatol. 1995 Jul-Aug;15(4):293-6; Merlob P, Eshel Y, Mor N
  • Nonsurgical Correction of Congenital Auricular Deformities in Children Older than Early Neonates; Plastic & Reconstructive Surgery. 101(4):907-914, April 1998; Yotsuyanagi, Takatoshi M.D., Ph.D.; Yokoi, Katsunori M.D., Ph.D.; Urushidate, Satoshi M.D.; Sawada, Yukimasa M.D., Ph.D
  • The Constricted Ear; Clin Plast Surg. 2002 Apr;29(2):289-99, viii; Paredes AA Jr, Williams JK, Elsahy NI
  • Technique for Correction of Lop Ear; Plastic & Reconstructive Surgery. 85(4):615-620, April 1990; Elsahy, Nabil I. M.D.
  • A Method of Treatment of Constricted Ears with a Conchal Cartilage Graft to the Posterior Auricular Plane; Plastic & Reconstructive Surgery. 92(4):621-627, September 1993; Ono, Ichiro M.D.; Gunji, Hironori M.D.; Sato, Morihiro M.D.; Kaneko, Fumio M.D. (photos of technique from this article)
  • 5-Year Series of Constricted (Lop and Cup) Ear Corrections: Development of the Mastoid Hitch as an Adjunctive Technique; Plastic & Reconstructive Surgery. 102(7):2325-2332, December 1998; Horlock, N. F.R.C.S.; Grobbelaar, A. O. M.Med.(Plast.), F.C.S.(S.A.), F.R.C.S.(Plast.); Gault, D. T. F.R.C.S. (photos of spectrum from this article)

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