Tympanoplasty is the surgical reconstruction of the tympano-ossicular system and includes: can alplasty, meatoplasty, myringoplasty, and ossiculoplasty.

Myringoplasty is a technique for reconstructing a vibrating tympanic membrane. Widening of the ex ternal auditory canal (canalplasty) is an integral part of myringoplasty. It should be carried out for the grafting of all anterior perforations of the tympanic membrane because it gives the necessary surgical access for their adequate repair. Canalplasty also facilitates healing, cleansing, and second-stage ossiculoplasty. Meatoplasty is used to enlarge the opening of the lateral (cartilaginous) external canal in proportion to the size of the medial (bony) canal.

Different types of ossiculoplasty are necessary to restore the sound transmission from the drum to the inner ear.

Eradication of disease.

Restoration of tympanic aeration.

Reconstruction of a sound-transformer mechanism.

Creation of a dry, self-cleansing cavity.

Preoperative Investigations

Tubal function. The function of the eustachian tube is assumed to be normal when the Valsalva or Toynbee maneuver is positive.

Tympanometry is performed if the above-mentioned test results are negative.

Knowledge of eustachian tube function is important for proper surgical planning and to assess the chance of a possible hearing improvement. Negative tubal tests, however, are not an absolute contraindication for tympanoplasty. Normal ventilation may indeed be restored in spite of a negative tubal test by surgical excision of scar tissue occluding the tympanic ostium of the eustachian tube. Good aeration of the opposite ear may serve as an indicator of good tubal function. Pneumatization of the temporal bone as viewed by conventional radiography or computed tomography (CT) scanning remains one of the best measures of evaluation of the ventilation of the middle ear cleft in early childhood.

Temporary closure of perforation. Applying a disk of wet Gelfilm over the remaining drum permits temporary closure of a perforation. Resulting changes in hearing permit assessment of the condition of the ossicular chain and/or the oval and round windows.

Fistula test. The fistula test should always be performed when a patient complains of vertigo or in the presence of a cholesteatoma. Be certain to maintain a good seal when performing the fistula test to avoid a caloric response to cold air. It is the unexpected fistula that leads to deafness at surgery. Therefore, be aware that a negative fistula test does not exclude the presence of a fistula.

Rules for Preoperative Treatment

The operating microscope, or equivalent magnification, and aspirating tubes are an essential prerequisite for proper preoperative evaluation and treatment. The aim is to operate, if possible, on a dry, well-ventilated ear.

Clean the external canal using aspiration to remove fluid and 3% hydrogen peroxide (H₂O₂) to mollify dry secretion.

Apply antibiotic ear drops or ointment on a strip of 0.5-cm ribbon gauze. The gauze should not be impregnated with too much ointment. The purpose of introducing gauze into the external auditory canal is:

1. To avoid free diffusion of ototoxic drugs into the middle ear, and;

Avoid:

1. Systemic antibiotics, if there are no signs of general infection;

2. the use of free ear drops since in the presence of a perforated drum a sensorineural deafness may be induced (exception: ofloxacin ear drops).

If the ear does not become dry after 3 to 4 weeks of treatment, surgery can be performed in spite of the draining ear.

Antibiotic Treatment

Dry ears. Routine perioperative i.v. antibiotic treatment (e.g., amoxicillin with clavulanic acid or ciprofloxacin) is given for myringoplasty, tympanoplasty with extensive bone work (mastoidectomy, epitympanectomy, posterior tympanotomy, modified radical operation, and reconstruction of an open cavity).

No antibiotics are given routinely for reconstruction of the ossicular chain when the drum is intact (particularly in second-stage operations). Routine antibiotic treatment—amoxicillin and clavulanic acid—is given whenever the inner ear is exposed (stapedectomy, stapedotomy). Ciprofloxacin is preferred in revision surgery.

Draining ears. If the preoperative treatment did not succeed in drying the ear, a bacteriologic investigation of the persisting secretion is performed only when the secretion is purulent.

A predominantly clear mucous secretion is related to hyperplastic changes of the mucosa of the tympanic cavity and does not require bacteriologic investigation. Gramnegative microbes such as Pseudomonas pyocyanea and Proteus mirabilis, as well as fungi, are commonly found in most middle ear secretions because of a superinfection originating from the external canal. Ciprofloxacin is preferred in this situation.

Preoperative Preparation