Pediatric Microtia Surgery Treatment & Management

Approach Considerations

If hearing in the unaffected ear is found to be normal, a hearing aid is not usually recommended. If the child is found to have severe hearing loss in the normal-appearing ear, or if the child is born with bilateral microtia and atresia, hearing aids should be fitted immediately after birth.

Unilateral Microtia/Atresia

Total external ear reconstruction requires 3-4 surgical stages. On the average, intervals of 2-3 months elapse between surgical stages to optimize the healing process. Some surgeons favor a 1- or 2-stage procedure. Tanzer and Brent advocated multistage reconstructions, which are currently favored by most ear reconstruction surgeons.

• First stage - Rib cartilage harvesting with carving and sculpting into the shape of an ear and placement of sculpted framework under the skin pocket of the microtic ear
• Second stage - Formation of the lobule (ie, earlobe)
• Third stage - Elevation of the ear with insertion of a postauricular skin graft
• Fourth stage - Formation of the tragus with a skin/cartilage composite graft from the contralateral ear and full-thickness skin graft for the conchal area from the contralateral ear

Stage 1 - Rib cartilage harvesting and framework insertion

The first stage consists of 2 separate procedures: (1) harvesting the costal cartilage (see the image below) and (2) inserting the carved sculpted cartilage into a skin pocket under the microtic ear.

A slightly oblique chest incision is made over the sixth, seventh, and eighth ribs close to the sternum (on the side opposite the microtic ear). The cartilaginous portion of the eighth rib and the synchondrosis of the sixth and seventh rib are harvested according to a previously measured template. A small piece of extra synchondrosis of rib 6 is harvested for use during the third stage in unilateral cases and third and fourth stages in bilateral cases.

The sixth and seventh rib synchondroses form the base framework of the new ear. The eighth rib is used to form the rim or helix (see the image below).

Once the 3 pieces of rib are carved, sculpted, and sutured together, the shape shown in the image below ensues.

In cases of unilateral microtia, an extra piece of rib is harvested and embedded in a separate incision posterior to the reconstructed ear. This piece of cartilage is used as an extra support to keep the reconstructed ear elevated during the third stage.

In cases of bilateral microtia, extra pieces of rib are harvested for 2 reasons. Part of the saved rib is used for support to keep the ear elevated during the third stage. The other part of the saved rib is used for tragus construction bilaterally during the fourth stage. The new framework is inserted into a skin pocket under the microtic ear (see the images below).

Patients are sent home with pain medication and antibiotics. An ear dressing is applied during surgery and left intact for about 3 days. At that time, the wound is checked and the ear is rebandaged. The drain stays in place for about 5-7 days to provide negative suction so that the skin can coapt to the newly inserted framework. The sutures are removed on the seventh postoperative day. Contact sports are restricted for approximately 4-6 weeks. The hair may be washed a few weeks after surgery. The next stage may proceed approximately 3 months later.

Stage 2 - Transposition of the lobule

The second stage consists of forming the earlobe, otherwise known as transposition of the lobule. An incision is made both in front and behind the skin vestige (see the image below).

The skin vestige is then rotated into place via a Z-plasty and spliced to the cartilaginous framework that was sculpted during the first stage (see the image below). Sutures are placed, and antibiotic ointment is applied.

Patients are sent home with pain medication. An ear dressing is placed for 3 days. Sutures are removed on the seventh day postoperation. Patients are restricted from contact sports for about 3-4 weeks. The hair may be washed a few weeks after surgery. The next stage may proceed approximately 3 months later.

Stage 3 - Elevation of the ear and skin graft placement

Approximately 3 months after the second stage is completed, the third stage is begun. The third stage consists of elevating the newly formed ear from the side of the head. A 0.017-inch skin graft is placed on the undersurface. The graft is taken from the upper buttock area on the same side as the microtic ear. The graft harvest site is hidden under the bathing suit or underwear region (see the image below).

An incision is made behind the newly constructed ear, and the undersurface is undermined. The banked cartilage harvested from the first stage is then placed under the framework to provide support and elevation (see the images below). This raw tissue is then lined with a skin graft. Once the graft is secured, a bolster dressing is placed behind the ear. An ear dressing is applied. In addition, a special bandage is placed over the graft site.

Surgery lasts approximately 2.5 hours, and the patient goes home the same day with pain medication and antibiotics. The ear dressing and the sutures are removed on about the seventh postoperative day. The upper buttock dressing is left intact until it falls off on its own. Contact sports are avoided for about 4 weeks. The hair may be washed a few weeks after surgery. The final stage may proceed approximately 3 months later.

Stage 4 - Formation of the tragus and excavation of the conchae, achieving symmetry of the ears

Approximately 3 months after the third stage is completed, the fourth and final stage is begun. The fourth stage consists of formation of the tragus, excavation of the concha (to mimic an actual opening into the ear), and achieving symmetry of the ears.

First, the reconstructed ear is marked for the future placement of the tragus. An incision is made as shown in the image below.

At this point, a J-shaped incision is made in the conchal area of the microtic ear. A skin/cartilage composite graft and a full-thickness skin graft are taken from the contralateral ear as shown in the image below. Once the grafts are taken and the skin is sutured, the projection of both ears is very similar.

The skin/cartilage graft is secured in place where the initial incision was placed on the microtic ear. The tragus is then formed. Once the concha on the microtic ear is excavated, the second skin graft is placed to line the raw conchal tissue. The ear now has the appearance of having an external auditory canal. A bolster is placed over the conchal area, and an ear dressing is placed over both ears.

Patients go home with pain medication. Ear dressing and sutures are removed around the seventh postoperative day. Contact sports are avoided for approximately 4 weeks. The hair may be washed a few weeks after surgery.

The images below depict the transition from a typical preoperative grade III microtia to the final result.

Bilateral Microtia/Atresia

Children born with bilateral microtia/atresia are treated differently than those with unilateral microtia/atresia.

A CT scan of the temporal bones is obtained before the onset of the first microtia surgery. This depicts the anatomy of the outer, middle, and inner ear.

After the first stage of surgery, the contralateral first stage of surgery may begin within 4-6 weeks. Approximately 3 months are allowed to pass before proceeding to the next stage. To minimize surgeries, both second-stage operations may be performed at the same time. Three months later, both ears may be separated from the head at the same time.

During the final stage, the tragus on each side may be constructed by retrieving the saved rib obtained from the first stages. After 3-4 months, the canal may be drilled to improve hearing status (if the anatomy is favorable). As previously stated, pinna reconstruction is begun at an earlier age for several reasons. Because no ears are present for comparison, the cartilaginous framework may be sculpted using a smaller rib. In addition, the middle ear surgery may begin at an earlier age in order to improve the patient's hearing sooner.

Although beginning the middle ear surgery early for hearing improvement is advantageous, the surgical risks must be considered. The most common risk associated with middle ear surgery is restenosis of the external auditory canal. The most detrimental risk is actual damage to the facial nerve. As a result, the CT scan must be examined carefully in order to track the location of the facial nerve.

For more information, patients and their parents may visit the Microtia-Congenital Ear Institute Web site.

Because of the complex anatomy of the external ear, great attention to detail must occur during the reconstruction. The most common complication of microtia reconstruction is an unpleasant cosmetic result. Other less common complications are infection, bleeding, or pneumothorax during the rib harvest. Hematoma formation under the skin pocket of the new ear cartilaginous framework can also result in an infection. Excessive cartilage resorption is an uncommon complication.

Although some children do not want surgery, parents must discuss the benefits of the reconstructions with them. With good results, all children can have very positive physical and psychological outcomes.

Total auricular reconstruction is one of the most challenging procedures performed by the ear reconstruction surgeon. Understanding the psychological issues faced by patients with microtia and providing education to the parents of these patients is fundamental to a successful microtia practice.

Complete knowledge of the 3-dimensional anatomy of the ear and sound surgical principles of soft tissue management and tissue transfer is necessary.

Children younger than 3-4 years with a microtic ear usually have little psychological impact. After this time, children usually begin to notice that their ears are different. Parents must treat their child with microtia the same as other children. Although parents may not realize, children feel the anxiety of their parents. Parents who attempt to cover the ear tend to hinder the confidence of the child. The children with the lowest self-esteem tend to be the ones whose parents transmitted anxiety about the ear throughout their childhood.

Patients whose ears have not been reconstructed as children may have difficulty dealing with the peer pressure of adolescence. During this time, fitting in with their peers is of much importance.

Teenagers are particularly conscious of their looks and are very aware of their microtic ear. Although they tend to be more eager to undergo surgical reconstruction than younger children, their expectations tend to be more unrealistic. Therefore, counseling patients and parents as early as possible is imperative. With early counseling, expectations become much more realistic, and the patients are able to deal with certain social issues much easier.

Because of the rarity of microtia, most parents and some health care providers may not fully understand how to care for these children. Microtia is rarely noticed on prenatal ultrasonography, primarily because of the complexity of the fetal ear and the inherent nature of conventional 2-dimensional ultrasound. Some authors suggest the use of 3-dimensional ultrasound to better examine the fetal ear for purposes of prenatal diagnosis and genetic counseling.

Cao and Vacanti et al have provided promising advances in the technique of microtia reconstruction. This group has evaluated a tissue-engineered autologous cartilage to use in place of harvested rib cartilage. Autologous chondrocytes are harvested and seeded into a mesh that is shaped in the form of the normal ear. This new framework is then inserted under the microtic vestige as a first-stage procedure. If successful in the long term, this form of cartilage harvesting may replace present-day rib harvesting. The future of microtia surgery holds much promise.