Ear Microsurgery
Microsurgery of the ear is a specialized procedure designed to reconstruct a perforated tympanic membrane (eardrum) or repair the small bones of the middle ear. A perforated eardrum can result from acute or chronic infections or, less commonly.
In some cases, mastoid exploration a procedure to examine and treat infections in the mastoid bone may be performed alongside ear microsurgery, depending on the severity of the condition.
This delicate surgical technique helps in not only removal of the disease but also restores hearing and prevent further complications, significantly improving the patient’s quality of life.
Tympanoplasty
The term tympanoplasty implies reconstruction of the middle ear hearing mechanism with or without tympanic membrane grafting. Grafting is impossible without sufficient visualization of the entire tympanic membrane with one position of the microscope. This is achieved with meatoplasty and canalplasty. Meatoplasty is defined as the enlargement of the lateral cartilaginous portion of the external auditory canal (EAC). Canalplasty consists of widening the bony medial portion of the EAC.
Grafting of the tympanic membrane is generally called myringoplasty when the middle ear cavity is not entered and tympanoplasty when the surgeon works also in the middle ear in the presence of an intact ossicular chain. In practice, only small perforations may be closed without extensive work in the middle ear. Therefore, in this atlas, the term myringoplasty is used for all reconstructions of the tympanic membrane that are not associated with ossiculoplasty. A synonymous term would be tympanoplasty without reconstruction of the ossicular chain. The procedures used for meatoplasty and canalplasty will not be described separately but in conjunction with the different surgical steps of the retroauricular approach.
Surgical Approaches
Transcanal Approach
With this approach surgery is performed through ear speculum in the external canal. The transcanal approach is indicated when the EAC canal is sufficiently wide to allow complete visualization of a posterior perforation. The approach cannot be used when the anterior margin of the perforation is obscured by the overhanging canal wall.
Endaural Approach
For this approach, a small incision is made between the tragus and the helix. The entrance of the canal is enlarged with specially designed endaural retractors. A posterior overhang of bone can be eliminated with a burr (broken line), A more anterior surgical view is achieved than with the transcanal approach. However, most anterior perforations are still obscured by the anteroinferior overhang of the bony external canal.
Retroauricular Approach
With this approach the pinna and the attached retroauricular tissues are reflected anteriorly. Removal of the overhanging canal walls (canalplasty, broken lines) provides for complete exposure of the anterior edge of the tympanic membrane.
Selection of Surgical Approach
The transcanal approach is mostly used for repairing larger acute traumatic perforations. The endaural approach is selected for posterior perforations and the retroauricular approach for anterior perforations whose margins cannot be seen entirely through the intact external canal.
Endoscopic ear surgery
- Endoscopic ear surgery allows a minimally invasive approach
to the middle ear. - The surgery can be performed in addition or in place of the
use of the microscope to perform the procedure. - The endoscope has the advantage
of performing the surgery using only ear canal incisions instead of the
traditional behind the ear incision which ensures minimal postoperative discomfort and faster recovery.
Mastoidectomy and Epitympanectomy
Disease involving the middle ear can extend to the mastoid and require surgical procedures involving this bone. Surgery limited to the mastoid is defined as cortical or simple mastoidectomy. A cortical mastoidectomy is mainly carried out in mastoiditis to remove disease/granulations from infected mastoid air cells.
It can be combined in the treatment of middle ear disease with tympanoplasty (tympanomastoidectomy). The term intact canal wall or closed cavity tympanomastoidectomy is used when the posterosuperior canal wall is preserved. The term canal wall down or open mastoido-epitympanectomy implies removal of the posterosuperior canal wall and the complete exenteration and exteriorization of both mastoid and epitympanum. The most common indication for an open mastoido-epitympanectomy is chronic otitis media complicated by a cholesteatoma.
Cholesteatoma
Cholesteatoma is defined as the presence of keratinizing squamous epithelium within the middle ear or in other pneumatized areas of the temporal bone with symptoms of foul smelling pus discharge, hearing loss and if left untreated, can advance to threatening complications
cholesteatoma involves enzymatic degradation of the bone around middle ear which can advance to threatening complications like disease spread to meninges/brain, sigmoid sinus, facial nerve ( leading to facial paresis, it can erode the bone of inner ear, leading to giddiness and labyrinthitis causing irreversible damage to hearing and balance and sometimes complications like CSF leak etc.
this makes the surgical treatment for cholesteatoma a decision of paramount importance
Surgical Treatment of Acquired Cholesteatoma
Aims
- Eradication of disease.
- Prevention of recurrent and retention cholesteatomas.
- Formation of a dry and self-cleansing cavity.
- Restoration of tympanic aeration.
- Reconstruction of a sound-transformer mechanism.
Myringotomy
A myringotomy is a procedure to create an opening in the ear drum to allow fluid that is trapped in the middle ear to drain out. The fluid may be blood, pus,thick mucus or watery serous fluid. In many cases, a small ventilation tube, called grommet is inserted into the opening in the ear drum to help maintain drainage.
A myringotomy may be done:
- To restore hearing loss caused by chronic fluid build-up and to prevent delayed speech development caused by hearing loss in children with middle ear fluid
- To place tympanostomy tubes these tubes help to equalize pressure. It may also help prevent recurring ear infections and the accumulation of fluid behind the ear drum.
- To help treat an ear infection that is not responding to medical treatment
- To take sample fluid from the middle ear to examine in the lab for the presence of bacteria or other infections
After the procedure, pain or pressure in the ear due to fluid build-up gets alleviated. Hearing loss due to fluid build-up improves as well.
Ear CSF Leak ( CSF otorrhea)
Ear CSF leak closure requires cutting the skin behind the ear and removing portions of mastoid (honeycomb-like, bony tissue) to access the source of the CSF leak around the ear. Using your own tissue or a biomaterial graft, the surgeon repairs the leak and seals the surgical opening.
