The ear is an important organ among the five senses, responsible for the sense of hearing and the sense of balance in the body, and, at the same time, plays an important aesthetic role in a person’s looks and appearance. The ear is usually divided into three parts: the outer ear, the middle ear and the inner ear. Each of these three parts performs its own role in accomplishing the God-given functions that enable humans to enjoy beautiful music and communicate effectively. Deformities of the ear will likely affect hearing and aesthetics. When an ear deformity occurs, deformities of the middle and inner ear cannot be seen but can severely affect hearing, and deformities of the outer ear are not only easy to detect, but may also affect hearing. This article discusses the medical issues related to outer and middle ear malformations and the issues that patients are most concerned about, in order to provide useful help and guidance to patients. 1.What is microtia? Usually we classify microtia into 3 degrees, I degree is the smallest degree of deformed ear, II degree is less deformed and looks like a small ear, and III degree is just a curly, weenie-like tissue without any shadow of an earwig. Also troublesome is the fact that with microtia, atresia of the external auditory canal and malformation of the middle ear often accompany the condition, due to the fact that during embryonic development, the external and middle ears originate from the same embryonic layer. They often occur at the same time. While current research is inconclusive as to the cause of microtia, one thing is certain: it is not the fault of either parent to cause microtia, and parents need not feel guilty about it. It is common for parents of children with microtia to feel guilty, but there is nothing they could have done to prevent their child’s microtia from occurring, and the parents are innocent. The probability of microtia occurring in a normal couple wanting to have a child is 1 in 5000-7000, however, if both parents of a child with microtia want to have a child again, the probability of having another child with microtia rises to 5%, or 1 in 20. 5% of the immediate family members of a patient with microtia have a family history of this condition, and the probability of the patient with microtia having a child with microtia is also 1 in 20. This is an issue that needs to be brought to the attention of parents, as it is currently difficult to detect microtia on prenatal testing. Of course, most children with microtia do not have other deformities. About 1/3 of the children have hemifacial microsomia and 15% have facial nerve hypoplasia. Other malformations such as cleft lip, cardiovascular malformations or urinary problems are less likely. Children start to pay attention to their malformed ears around 3 to 3.5 years of age. They compare their ears in front of a mirror and begin to refer to their “little ears”. When children are concerned about their small ears, parents should tell them that they are born with small ears, and that when they grow up, doctors will “grow” their small ears and treat them as if they were completely normal children. The main reason is that family members are overly concerned about this matter, and this worry is passed on to the child. Can microtia be treated? There are many ways to treat and rehabilitate microtia, whether it is a hearing loss or a malformation of the ear. The most common treatments are surgical reconstruction of the ear and hearing reconstruction. However, surgery for microtia is generally not recommended before the age of 6 years because it is not until the age of 6 that the child’s rib cage is large enough to carve an ear brace to the size of the normal ear on the opposite side of the ear. before the age of 6, the child is not particularly concerned about the abnormal ear, which does not cause severe trauma, and is not very cooperative with the surgeon in terms of post-operative care. after the age of 6, the child begins to have a greater willingness to have the ear repaired and cooperates actively with the surgeon during and after the surgery. After the age of 6, children begin to have a stronger desire to have their ears repaired and are able to cooperate with the surgeon during and after surgery. Microtia repair surgery is a very challenging procedure in which the surgeon must sculpt the rib cartilage into a three-dimensional auricular shape in an operating room setting in a limited amount of time, and then make a “pouch” under the skin into which the sculpted framework is placed without disrupting the blood supply to the skin. This is like putting a 5-pound object into a 2-pound space, and doing it on a living body! In addition, because cartilage does not show up on x-ray in the same way that bone formation does, it is impossible for the surgeon to know how well the rib cartilage has developed before the surgery. No matter how difficult it may be, the surgeon must do his or her best to carve an auricular scaffold that is as realistic as possible. Sculpting an implant using the patient’s own rib cartilage is the most sophisticated technique available. An auricle made from one’s own rib cartilage is “living” and therefore can grow with age, whereas an auricle made from artificial material obviously cannot grow with age. The benefits of restoring the auricle with your own living tissue are obvious. Auricles reconstructed from the rib cartilage of the patient are “living” and can grow with age, and can repair themselves after injury. Within 4-6 weeks after the surgery, the child can play normal sports, such as swimming and gym class, without any special concern for trauma to the auricle. Basically, there is no need to restrict any sports in particular. Because it is a living tissue reconstruction, the child can participate in sports at 5 weeks postoperatively without special concern for the operated ear or chest wall. If there are post-operative discomforts in the following stages II and III of the procedure, also mainly in the ear, these can be addressed on an outpatient basis. Allograft tissue is considered “foreign material” by the body, and in order to ensure the success of the transplant, the patient will need to take medications for the rest of their life to prevent rejection, which can have very serious side effects, such as causing problems with the heart or kidneys. In fact, the doctor only needs to spend an extra 20 minutes to take the patient’s rib cartilage and another 30 minutes to carve it, and the use of allogeneic tissue is unnecessary. Artificial materials are currently subject to further research. 3. Hearing problems in patients with microtia? Most patients with microtia are unilateral with one normal ear. Although they have adapted to hearing in one ear, they still have problems with sound localization and hearing in noisy environments. In the case of binaural malformations, the problem is more severe and these children must be fitted with bone conduction hearing aids in the first few months of life to facilitate their speech development. Children with microtia can have brainstem auditory evoked potentials (BAER) performed within a few days or 2 weeks of birth, which can detect hearing problems much earlier than electrical audiometry. This test is even more important in children with binaural deformities. Children with monaural hearing usually do not need hearing aids, but patients with binaural microtia need hearing aids to help their speech development. If the microtia is unilateral, these children do not need hearing aids and most have good speech development. A bone-anchored hearing aid (BAHA) is a box-shaped device attached to a metal fixture that is anchored to the skull by two surgical methods, and this hearing device can provide better sound quality than traditional bone-conduction hearing aids. It needs to be surgically placed and requires scalp care during the hearing aid application. If a bone-anchored hearing aid is fitted prior to otoplasty, it is required to be placed very far back in the skull to prevent the resulting scarring from interfering with the later reconstruction of the ear. Many BAHAs are placed improperly resulting in a lost opportunity for auricular reconstruction. In my opinion, if BAHA implantation is being considered for a small child, it is best to wait until after the auricular reconstruction. In children with bilateral ear deformities, traditional bone conduction hearing aids can be used first, and then BAHA surgery can be performed after the auricular deformity has been repaired. Children (with or without microtia) are prone to ear infections and must be especially aggressive in treating infections in the healthy ear with microtia. If these children have frequent ear infections, it is important to monitor hearing and speech development frequently. Because the urinary system develops at the same time as the ear, malformations of the urinary system are more common in patients with microtia (about 4%). Ultrasound of the kidneys can be performed to understand the condition of the kidneys. 4. Is auricular repair or external ossiculoplasty and tympanoplasty performed first? The surgeon usually utilizes rib cartilage sculpted into an auricular scaffold for implantation. The outcome of the auricular deformity repair depends on a pristine, scarless skin in the area of the ear implant. Reconstructing the auricle first to repair a microtia does not interfere with atresia surgery, but the reverse is not true: if atresia molding is done first, the skin in the area is no longer suitable for auricular repair, and the surgeon must replace the original, well-formed skin with a fascial flap to cover the auricular scaffold. If the atretic external auditory canal is not opened at an early age, will the auditory center not be able to comprehend the information it receives anew after hearing reconstruction at an older age? While this concern is entirely valid for the visual system, it is fortunately not at all necessary for the auditory system. Signals from one ear are transmitted to the same side of the brain and to the other side of the brain early on in the entire auditory reflex pathway; in other words, from birth (and even earlier) the bilateral auditory centers work together to collect and process the information coming from both ears. This means that regardless of when the external auditory atresia opens, the bilateral auditory centers can process and understand the new signals it receives. Because of these reasons, we recommend delaying microtia/atresia surgery until after the age of 6-8 years. In patients with unilateral atresia, opening the atretic canal can improve a child’s hearing in noisy environments (loud classrooms, playgrounds, etc.) as well as spatial localization of sounds. Approximately 50% of patients with microtia/atresia have a well-developed middle ear, making them candidates for reconstructive hearing surgery, which requires a CT scan to determine. The aim is to (1), find out if there is an associated congenital cholesteatoma (15% prevalence in patients with atresia). (2) To find out the development of the middle ear mastoid. (3) To find out the deformity of the auditory ossicle chain. (4) Understand the development of the inner ear. Because early on, even if a cholesteatoma is present in the middle ear or external auditory canal, it does not cause much damage, CT of the middle ear mastoid is not necessary until 3-4 years of age. Another CT scan is needed before surgery at age 6-8 years.The CT scan can give us information about the development of the middle ear and help us decide if the patient is a good candidate for reconstruction of hearing function. Treatment of congenital auricular malformations with atresia requires close collaboration between the otologist and plastic surgeon. The repair of congenital auricular malformations can be divided into 3-4 stages. The plastic surgeon’s work should be the first to be performed. Important improvements to the surgical approach have been made by organizing hearing reconstruction and auricular reconstruction into a staged surgical sequence, allowing the patient to complete hearing and auricular reconstruction and rehabilitation in the shortest possible time. The staged approach allows for the complete restoration of congenital auricular malformations associated with atresia. Stage I: total auricular reconstruction (auricular scaffolding with own rib cartilage); Stage II: reconstruction of the external auditory canal with hearing reconstruction with earlobe and ear screen reconstruction; Stage III: erection of the ear (the reconstructed auricle is lifted up from the area of the mastoid skin to form an auriculo-cranial angle between the skull and the ear); and Stage IV: repair of further auricular details (if necessary). Early surgery should be performed when patients with unilateral external aural atresia have evidence of middle ear cholesteatoma, infection, or thin atresia membranes. Children with congenital auricular malformations, especially unilateral patients, should usually undergo repair surgery after the age of six to eight years. This depends on the growth and development of the child. Patients with bilateral congenital auricular malformations combined with atresia may be operated on earlier, but total ear reconstruction can only be performed if the child has enough cartilage tissue. Surgical risk The technical difficulty and risk of ear reconstruction and auditory reconstruction surgery is high, and it is difficult to achieve a normal surgical result in terms of both aesthetics and hearing recovery, which parents and patients must be aware of. When placing the grafted cartilage during surgery, the skin may become gangrenous due to the severe pulling on the surface skin; gangrene of 1 to 2 mm can be treated with ointment and careful observation until healing occurs. If the gangrenous skin area exceeds 5 mm, it can be repaired with a tipped parietal-temporal flap. chondritis with cartilage resorption may occur; improper placement of the cartilage scaffold and resorption of the cartilage can cause infection. All grafting steps have the potential for graft failure. There is also a higher chance of keloid formation than with flaps taken from the abdomen and buttocks. In addition, malposition of the reconstructed ear and contraction of the skin graft behind the auricle are associated with keloid formation in the donor or skin graft area. Not all patients with ear deformities are candidates for ear canal reconstruction and hearing reconstruction, requiring an exhaustive audiologic and middle ear mastoid development morphologic evaluation by an audiologist and otologist. For auditory reconstruction the risks are even greater, as the surgery involves the facial and auditory nerves, and a small amount of inadvertence can lead to serious complications. Therefore, the concept of total reconstruction needs to be emphasized, with a teamwork of otologists and plastic surgeons working together to simultaneously reconstruct and repair auricular deformities and atresia. Plastic surgeons performing auricular reconstructive surgery should ensure that the otologist has completed the necessary audiologic and imaging evaluations. Prosthetic ears and hearing aids are options for patients who are not good surgical candidates. Breakthroughs in cell culture and cell scaffolding techniques in tissue engineering will impact the future of total auricular reconstructive surgery. We are committed to this research and look forward to breakthroughs.