Auricular Reconstruction – A Possible New Method?

Robert Traynor
September 12, 2012

As much as 5% of the population is born with some kind of ear malformation.  Most of these malformations are minor, but others such as Microtia usually involve the middle ear as well and can be much more than mere malformation of the auricle.  Paul Stanley of KISS grew up with a class 3 Microtia and, to keep the bullies away, he grew his hair long so others did not realize that there was a malformation (Left is Paul Stanley ready for concert, right is his microtic ear).

Although there are genetic and non-genetic causes of pinna malformation the most common causes are trauma, skin lesion excisions, and hematomas or infections. Hematoma or Cauliflower ear  is an acquired deformity of the outer ear. It is usually due to blunt trauma. When the cartilage of the ear is injured by trauma or inflammation, the blood supply from the skin is disrupted. It often forms a large pocket of blood, called a hematoma. As the injury to the ear heals it can shrivel up and fold in on itself and appear pale, giving it a cauliflower-like appearance, hence the term “cauliflower ear.” Wrestlers, boxers, and martial arts practitioners are particularly susceptible to this type of injury.   Pinna malformations can also result from  lacerations and other injuries, including automobile accidents, that cause trauma to the a or  injuries, such as VanGogh’s sword fight , that amputated his auricle.

Brief History of Pinna Reconstruction

Reconstruction of the pinna has a long and varied history.  The earliest recored reconstruction is an 8th-century Indian text, the Susrata, which describes the use of a cheek flap to repair an earlobe defect.  At the time, the surgeons in India were doing lots of Rhinoplasties, as it was common for those guilty of certain crimes to have their noses cut off. Earlobe modification/reconstruction was probably a simple extention of that procedure.  While a report from 1551 contains the first description of a total ear replantation, an Italian surgeon, Tagliacozzi,  described and illustrated the repair of both upper and lower ear deformities with skin flaps from behind the auricular region in 1597.  In Germany in 1845, Dieffenbach described repair of the ear’s middle third with an advancement skin flap, a technique that is occasionally still used today.   By 1920, Gillies was using autologous cartilage for total ear reconstructions. This evolution stemmed from the patient’s need to cope with the results of congenital ear deformities.

The Current Procedure

In 1959, Tanzer ushered in the modern era in ear reconstruction with the successful use of autologous costal cartilage grafts.   Although Brent (2011) reports that Tanzer (right), who was his teacher, began his pioneering work in ear reconstruction somewhat late in his career (he operated on only 43 microtia patients), his results were excellent.  Building upon Tanzer’s sound principles and his work, Dr. Burt Brent advanced the standards of ear reconstruction with autogenous materials and was the first to report the successful use of tissue expansion in reconstruction of the ear.  Brent operated on the child (left) 30 years after Tanzer operated on his uncle in the right side of the picture.  Success of ear reconstruction after trauma depends on two main factors. The first is vascular patency. To survive, a reconstructed auricle needs sufficient arterial inflow to nourish the healing graft. Also, venous congestion caused after partial or total amputation can result in cartilage loss. The second crucial factor is the availability of soft tissue cover over reimplanted or harvested cartilage framework. Lack of soft tissue cover following a traumatic injury can limit the options available for repair or can require more complex flap coverage.  Achieving a balance between size and shape is the most important factor for reconstructions after skin lesion excision. To make the ear appear normal, the surgeon must often sacrifice the size of the underlying cartilage to preserve a normal shape and avoid distortion. Because both ears are not typically seen at the same time, the preservation of anatomic landmarks is more important than maintaining symmetry of size.

 Next Generation of Auricle Reconstruction?

Johnson (2012) at Associated Press, reports that the  Laboratory for Tissue Engineering and Organ Fabrication at Massachusetts General Hospital, part of Harvard University in Boston has worked closely with stem cell biologists, material scientists, and engineers from the Center for Regenerative Medicine, MIT, Brigham and Women’s Hospital, and the Draper Laboratories. Collaborating with Professor Robert Langer from MIT, Cathryn Sundbeck, Director of Tissue Engineering at the MGH began building living tissues using living cells on specially designed degradable plastics. Until recent the process was totally impractical but this new invention is now patented and being tested worldwide.  The way it works is that bits of the patient’s own collagen (the tissue that gives ears their rigidity) can be grown around a custom-shaped titanium substructure. The structure grows in an incubator for a couple weeks and a new ear, ready to be covered with skin and sewn into place.  To prove the viability of the tissue, researchers have attached the ears onto rats,  where they have remained healthy for extended amounts of time. The procedure has not yet been approved by the FDA, but the lab expects to have approval in about a year.

Audiology Clinicians worldwide have all worked with patients that have Microtia or other auricular anomalies and this procedure offers hope for a normal looking and functioning anatomical appendage.

Next Week at Hearing International –

Next week we begin a 3 part series Audiology Outreach to the Northern Communities.  Dr. Jack Scott presents his experiences delivering audiololgical services to the Frozen north and the people of the Attawapiskat First Nation.

by guest Author:

   Jack M. Scott, Ph.D.

Western University

School of Communication Sciences & Disorders

H.A. Leeper Speech & Hearing Clinic

London, Ontario, Canada

 

 

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