Congenital microtia is an imprecise term that generally refers to severe auricle developmental insufficiency, often accompanied by external auditory canal atresia, middle ear malformation, and craniofacial malformations. Its incidence rate is 1 in 7000, with a higher occurrence in males, more commonly on the right side, and bilateral cases accounting for less than 10%. Microtia is typically divided into three degrees:
Degree 1: The various parts of the auricle are still recognizable but just smaller in size.
Degree 2: Most structures of the auricle cannot be recognized; the remnant ear is irregular, resembling a peanut, boat, or sausage shape, with external auditory canal atresia.
Degree 3: The remnant ear is merely a small skin tag or mound, or there may only be a misplaced earlobe.
When the auricle has not developed at all and there is no trace locally, it is called anotia, which is extremely rare.
What is ear reconstruction surgery? Ear reconstruction is a very complex procedure with many methods. Since ears consist of skin and cartilage scaffolding, ear reconstruction must primarily consider these two factors. Currently, autologous costal cartilage is considered the most ideal material for the ear scaffold; the mastoid area's hairless skin is regarded as the best choice for skin coverage.
Currently, there are no fully idealized biomaterials, so carving an ear scaffold from autologous costal cartilage remains the most widely used material in clinical practice. Its advantages mainly include: convenient procurement, easy to carve into shape, no rejection reaction as it is self-tissue, good long-term stability of the reconstructed auricle, and even individual younger reconstructed auricles can grow with the body. However, its drawbacks include: large surgical trauma, changes and injuries to the thoracic cage structure, thicker reconstructed auricles with suboptimal appearance, and a higher likelihood of absorption and deformation after transplantation in the long term.
Who needs ear reconstruction surgery?
1. For patients with bilateral microtia accompanied by external auditory canal atresia, priority should be given to external auditory canal and middle ear surgery to improve hearing. For unilateral microtia with external auditory canal atresia, earlobe reconstruction surgery should be performed first. Subsequently, whether middle ear surgery is necessary can be decided based on need. If conditions permit, earlobe reconstruction and middle ear surgery can also be combined into one procedure.
2. For patients with microtia accompanied by severe maxillofacial deformities, maxillofacial plastic surgery is generally recommended first. Otherwise, it would be impossible to position the reconstructed ear appropriately.
3. Auricle defects can severely impact a child’s normal psychological development. To avoid affecting their psychological development, ear reconstruction surgery should be completed before school age if possible, generally around 6 years old.
Ear Reconstruction Surgery Methods:
Reconstructing the auricle, with its complex and delicate surface structure, is a challenging and complex surgery. There are many methods, including Tanzer-Brent's staged auricle reconstruction method, one-stage auricle reconstruction, mastoid region skin expansion auricle reconstruction, etc.
1. Tanzer-Brent's Staged Method
The traditional method is Tanzer-Brent's staged approach, roughly divided into four stages: 1) Posterior transposition of the earlobe, 2) Harvesting rib cartilage, carving to form an ear scaffold implanted under the mastoid skin, 3) Elevating the auricle, free skin grafting on the wound surface, 4) Reconstructing the tragus and concha cavity. The entire process takes about half a year to a year.
2. One-Stage Auricle Reconstruction Method
This method saves time and money, completing the procedure within two weeks. However, due to insufficient skin in the mastoid region, the reconstructed ear extends backward and upward, carrying some hair, making the reconstructed ear thicker and having hair on the helical rim. As living standards have improved, this method is rarely used now.
3. Mastoid Region Skin Expansion Auricle Reconstruction Method
Due to sufficient skin supply, concealed postoperative scars, and stable long-term effects of the reconstructed auricle, the mastoid region skin expansion auricle reconstruction method has become one of the most commonly used auricle reconstruction methods today. Because there are no idealized biomaterials, autologous costal cartilage remains the preferred ear scaffold material in clinical practice. Its advantages mainly lie in convenience of procurement, ease of carving, no rejection reaction, and good long-term stability of the reconstructed auricle.
Phase one involves expander implantation surgery, i.e., surgically implanting a 100ml expander behind the ear in the mastoid region. This can be done as an inpatient or outpatient procedure. Water injection begins one week after surgery, 2-3 times per week, taking approximately 1-2 months to complete. After water injection, it's best to continue expansion for 3-6 months, resulting in thinner flaps with less retraction during phase two surgery, improving the outcome of the reconstruction. Phase two surgery can also be performed immediately after water injection completion.
Phase two involves auricle reconstruction, where rib cartilage is harvested and carved into a scaffold during surgery, then the expanded skin in the ear area is used as auricle skin to complete the reconstruction. This phase requires hospitalization, lasting about 10-14 days. After this phase, rest for about six months until the reconstructed auricle stabilizes and scars soften before proceeding to phase three surgery.
Phase three involves reconstructing the tragus, concha cavity, and earlobe repositioning on the already reconstructed auricle to make the reconstructed ear look more perfect and realistic.
Contraindications for Ear Reconstruction Surgery:
Auricle reconstruction is a difficult and complex surgery that should be approached with caution. Elderly individuals who are physically weak are advised to wear prosthetic ears instead of undergoing reconstruction surgery.