Tympanoplasty, also called eardrum repair, refers to surgery performed to reconstruct a perforated tympanic membrane (eardrum) or the small bones of the middle ear. Eardrum perforation may result from chronic infection or, less commonly, from trauma to the eardrum.
The tympanic membrane of the ear is a three-layer structure. The outer and inner layers consist of epithelium cells. Perforations occur as a result of defects in the middle layer, which contains elastic collagen fibers. Small perforations usually heal spontaneously. However, if the defect is relatively large, or if there is a poor blood supply or an infection during the healing process, spontaneous repair may be hindered. Eardrums may also be perforated as a result of trauma, such as an object in the ear, a slap on the ear, or an explosion.
The purpose of tympanoplasty is to repair the perforated eardrum, and sometimes the middle ear bones (ossicles) that consist of the incus, malleus, and stapes. Tympanic membrane grafting may be required. If needed, grafts are usually taken from a vein or fascia (muscle sheath) tissue on the lobe of the ear. Synthetic materials may be used if patients have had previous surgeries and have limited graft availability.
There are five basic types of Tympanoplasty procedures:
- Type I: Tympanoplasty is called myringoplasty, and only involves the restoration of the perforated eardrum by grafting.
- Type II: Tympanoplasty is used for tympanic membrane perforations with the erosion of the malleus. It involves grafting onto the incus or the remains of the malleus.
- Type III: Tympanoplasty is indicated for the destruction of two ossicles, with the stapes still intact and mobile. It involves placing a graft onto the stapes and providing protection for the assembly.
- Type IV: Tympanoplasty is used for ossicular destruction, which includes all or part of the stapes arch. It involves placing a graft onto or around a mobile stapes footplate.
- Type V: Tympanoplasty is used when the footplate of the stapes is fixed.