n order to have realistic expectations regarding what can be produced,
it is imperative for the patient and his/her family to understand the technical
limitations involved in surgically correcting microtia.
Aesthetic construction of the auricle is
one of the greatest challenges that confronts the plastic surgeon, and
is most consistently achieved by surgeons with artistic hobbies and backgrounds.
Comprised of a delicately convoluted cartilage frame covered by a fine
skin envelope, the ear is a difficult structure to draw or sculpt, let
alone surgically reproduce. Surgical construction of the auricle with autogenous tissues
is a unique marrying of science and art. While the surgeon's facility with
both sculpture and design is imperative, the surgical result will be equally
influenced by his adherence to sound principles of plastic surgery and
tissue transfer.
The ear is difficult to reproduce surgically because of its complexly convoluted form. The denuded cartilage framework conforms almost exactly to the ear's surface contours except for its absence in the earlobe, which consists of fibro-fatty tissue rather than cartilage.
In most microtic vestiges, the presence of this lobule tissue is a valuable asset in the repair (see Fig. 18). When the lobule is lost in total ear avulsions or absent in complete anotia, one best recreates it by shaping the bottom of the carved ear framework to resemble the lobe (see Fig. 11).
Figure 11 - Reconstruction of ear traumatically amputated by a dog bite. |
 |
Left. In the operating room, one can see the totally absent ear -- only the canal opening is left. The ear framework has been carved with its inferior tip representing the earlobe. Right. Result after first stage of surgery. Note how the total ear has been reconstructed, and even the earlobe is recreated; the earlobe will become further defined when the ear is "lifted" with a skin graft. From Brent, B.: Auricular repair with autogenous
rib cartilage grafts: Two decades of experience with 600 cases
.Plastic& Reconstructive
Surgery, 90: 355, 1992, with permission. |
|
The foundation of the surgical repair consists of surgically creating and placing an ear framework underneath the skin in the ear region, then refining the auricle with several soft tissue procedures [13, 14, 96]. As explained in the history section, artificial, alloplastic substances generally are not well tolerated as frameworks, cause skin ulceration and infections, and are frequently extruded and rejected [99]; and homograft cartilage (maternal, paternal or "banked") resorbs, distorts, or disappears within 18 months [12]. For all of these reasons, I strongly favor autogenous rib cartilage for auricular construction. Although its use necessitates a sizable operation and subspecialized expertise, it must be noted that, unlike a reconstruction utilizing artificial, alloplastic materials, a successful construction with autogenous tissue grows, heals, and is far less susceptible to trauma and, therefore, eliminates a patient's concern during normal activities [20]. I have seen silicone ear frameworks lost to even minor trauma up to 12 years after implantation. On the other hand, once safely passing the tenth postoperative day, it would be most unusual to lose an autogenous ear framework. To date, I have learned from more than 70 of my patients and families that their reconstructed ears have received a major trauma at one time or another; all these ears have survived the incident [23, 26,27].
