What is Tympanoplasty?
Tympanoplasty is a surgery to eradicate disease in the middle ear and to re-construct the hearing mechanism with or without mastoid surgery with or without tympanic membrane (Ear Drum) grafting.
What are the different types of Tympanoplasty?
Classification of Tympanoplasty:
- Type I: Defect in the tympanic membrane (Ear drum) is repaired by the graft after checking the mobility and status of the ossicular chain.
- Type II: There is a perforation with erosion of the malleus or part of incus
- Type II a: Graft is kept touching the malleus remnant, incus or incudo-stapedial joint.
- Type II b: Here the incus is also diseased. The body of the incus is refashioned to fit into the stapes head. The short process of incus goes under the handle of malleus. The ossicular chain is covered by a graft.
- Type III: Malleus and incus are absent
- Type III a: Low facial ridge: Graft is kept below the level of malleus touching the stapes head, called myringostapedopexy.
- Type III b: High facial ridge: Graft not directly touching the stapes head but below the level of the malleus.
- Type IV: Graft kept on the foot plate after separating the round window. Sound waves directly act on the foot plate.
- Type V: Sound waves enter through a fistula into the lateral semicircular canal.
- Type VI: Sono- Inversion: All sound waves enter through the round window keeping the oval window covered. (reverse direction)
Tympanoplasty can be done by taking an incision behind the ear, in front of the ear or through the ear canal which is rarely visible.
The most common grafts used to repair the ear drum are:
- Temporalis fascia
- Tragal or conchal cartilage
- Vein graft