Ear Reconstruction(Microtia)

In congenital deficiencies, patients should be evaluated for whether there are other accompanying anomalies, particularly in the head and neck region (such as whether the middle and inner ear structures are affected, facial asymmetry, deficiency or asymmetry of the lower jawbone), and their simultaneous treatment should be planned. In addition, many additional disorders such as cleft lip, cleft palate, urinary tract and kidney anomalies and facial clefts may also accompany it in these children.

Although many causes have been cited in the literature, such as infections (rubella), the use of certain drugs (thalidomide) and occlusion of the stapedial artery in embryonic life, in most patients with microtia genetic causes predominate or no known cause can be found.

Regarding the timing of the operation, the ages of 5-7 are preferred. It is recommended that the repair be performed before the child enters the school environment, for psychological reasons. However, especially in repairs where rib is to be used, operating at a very early stage is also not recommended, given the consideration that taking rib early may cause chest wall deformity. In addition, since an ear made very early during the growth period will remain small compared with the opposite ear when the child grows up, it is beneficial to wait until the period just before primary school.

Throughout history, many methods have been developed for the treatment of this condition. The first repairs were performed using the person's own tissues, and later prosthetic methods began to develop. Thanks to developing computer technologies and 3D printers, ear repairs with virtual designs have become possible today.

Although many ear reconstruction operations, such as making an earlobe from cheek tissue, have been described in the past, the first total ear reconstruction was performed by Gillies in 1920. A researcher named Tanzer described multi-stage ear reconstruction, and cartilage carving techniques that turned ear reconstruction into an art were described by Brent.

In these operations, preoperative planning is as important as the operation itself. In classic methods, the healthy ear side is traced with X-ray film or a transparent plastic sheet and measurements are taken. Since the template obtained will be a mirror image when viewed from the other side, this template also serves as a guide for the ear to be made.

Multi-stage ear repair:

• Creating the ear cartilage framework with rib and burying it under the soft tissue
• Raising the ear that was placed under the skin and lies attached, and creating the groove at the back called the sulcus
• Pulling the earlobe into its normal position
• Creating the structures called the concha and tragus

Single-stage ear repair:

• This is the procedure of wrapping the ear cartilages in a muscle sheath taken from the temple region. In this way, ear reconstruction can be performed in a single stage.

The only place in the human body with enough cartilage to create a cartilage framework is at the junction of the ribs in the chest wall. Generally, the chest wall on the side opposite to the ear to be made is used for the procedure. When the cartilage sheath called the perichondrium is preserved while the cartilage is taken, the cartilage structure re-forms there over time and permanent deformity of the chest wall can be prevented. However, it is very important to take cartilage from the chest wall without damaging the lung membranes. Although local anaesthetics are injected into the surrounding tissues after the procedure and oral painkillers are given to the patient, patients may complain of pain when breathing for a few days after the procedure.

This is the procedure of creating an ear externally in the form of a prosthesis, using the healthy ear as a model. The most important points in this method are that the prosthesis is fixed to the head firmly enough and that, when looked at, it cannot be seen that the ear is a prosthesis. To fix the prosthesis to the skull, the implant technology that dentists use for dental prostheses is used. After 2-3 implants placed in the skull bone have fused with the bone, very strong magnets are placed on their ends and the prosthesis is fixed to the head. Whether the prosthesis draws attention when looked at depends entirely on the skill of the clinician making it. Three-dimensional images of the opposite ear with 3D scanners or computed tomography

The better the colour and details of the prosthesis are adjusted, the more perfect the result will be. However, it should not be forgotten that even when the colour match is perfectly achieved, if the patient tans in the sun or changes in skin colour occur over time, the prosthesis will have no chance of adapting to these changes.

There is a ready-made material called Medpor for creating the framework of the auricle. However, since it is a hard material, if the patient lies on their ear after the ear has been created, this material often perforates the soft tissue covering it and comes out. For this reason, it is not much preferred in ear repair.

After the ear on the healthy side is imaged with surface scanners or three-dimensional tomography, a mirror image of this ear is obtained in a computer environment. If there are existing tissues on the deficient side, the existing image is subtracted from the mirror image, and the exact size of the repair needed on the deficient side is determined.

A prosthetic ear matching the determined model can be made, and this model can also be used to make an ear from the person's own tissues.

When this model is printed on a 3D printer and used as a guide during the operation, it provides much more detailed and accurate information than a tracing of the opposite ear on X-ray film or a transparent plastic sheet. In addition, for the cartilage, which one tries to shape by reducing it to two dimensions, a complete and accurate three-dimensional model is used.

The final point reached using virtual surgery is creating the framework of the ear from silicone using the model at hand. After the model of the ear deficiency is obtained as described above, a negative mould of the model is made. Medical silicone is poured into this mould to obtain the implant to be applied to the patient. This implant can be used in multi-stage ear repair by placing it under the skin in front of the hairline where the deficiency is, or in single-stage ear repair by wrapping it in a muscle sheath taken from the temple region.

Since ear framework implants made of medical silicone are soft, unlike Medpor implants they do not easily perforate the skin covering them and come out when lain on. Since the material used is biocompatible, they cause minimal tissue reaction in the tissues where they are applied.

In people with a low hairline, hair-bearing skin may remain on the auricle after the operation. In recent years, this problem has been eliminated by increasing the tissue volume with balloons placed in this area. In addition, in patients with facial asymmetry, the location where the auricle will be placed should be chosen carefully and symmetry with the opposite ear should be achieved as far as possible.