Stapedectomy

Stapedectomy is a microsurgical intervention in the middle ear. The operation is performed to restore the physiological mechanism of sound transmission by completely or partially removing the stapes. Stapedoplasty is then performed. [ 1 ]

The stapedectomy procedure was first performed in 1892 when Frederick L. Jack performed a double stapedectomy on a patient who was reported to still be hearing ten years after the procedure.[ 2 ] John Shea realized the importance of the procedure in the early 1950s and proposed the idea of using a prosthesis that mimicked the stapedial bone. On May 1, 1956, John J. Shea performed the first stapedectomy using a Teflon stapes prosthesis on a patient with otosclerosis with complete success.[ 3 ]

Indications for the procedure

The goal of any stapes procedure is to restore vibration of the fluids within the cochlea; enhancing communication is secondary to increasing sound amplification, bringing the hearing level to an acceptable threshold. [ 4 ], [ 5 ]

When the stirrup becomes immobile, a person loses the ability to hear. This usually happens for two reasons:

• congenital defect;
• anomaly of the temporal bone associated with excessive mineralization (otosclerosis). [ 6 ]

Stapedectomy is particularly often prescribed for the treatment of patients with otosclerosis.[ 7 ]

In general, indications for stapedectomy may be as follows:

• conductive hearing loss due to immobility of the stapes;
• the difference between bone and air conduction of sound is greater than 40 decibels. [ 8 ]

Preparation

Before performing a stapedectomy, the patient must undergo the necessary diagnostic stages - to determine the degree of hearing impairment, exclude contraindications, and also to select the optimal type of surgical intervention. The otolaryngologist will provide referrals for consultations from other specialists, such as a neurologist, endocrinologist, etc. [ 9 ]

Before the operation, an external otoscopic examination is mandatory, as well as other types of examination:

• measurement of hearing using audiometry;
• tuning fork study;
• tympanometry;
• assessment of spatial auditory function;
• acoustic reflexometry.

If otosclerotic changes are suspected in a patient, an X-ray and a CT scan are additionally performed, which make it possible to determine the scale and exact location of the pathological focus.

Immediately before the operation, the patient must provide the results of mandatory studies:

• fluorographic image;
• information about belonging to a certain blood group and Rh factor;
• results of general blood analysis and biochemistry;
• results of the analysis of blood clotting quality and glucose content;
• general urine analysis.

Technique stapedectomies

Stapedectomy is performed under general anesthesia.

During the surgical intervention, the surgeon inserts a miniature visualizer – a microscope – into the ear canal, as well as microsurgical instruments. A circular incision is made along the border of the eardrum, and the cut tissue flap is lifted. The doctor removes the stapes, replacing it with a plastic bone implant. After connecting the auditory ossicles, the tissue flap is returned to its place, and a tamponade of the ear canal is performed using antibiotics. [ 10 ]

Another way to perform stapedectomy is to make an incision in the patient's earlobe and remove the necessary fatty tissue from this area. It is then placed in the middle ear to speed up healing.

Stapedectomy with stapedoplasty

There are several methods of performing stapedectomy with stapedoplasty, so it is best to choose a clinical institution whose specialists use different intervention options to select the most suitable one on an individual basis. This operation is generally a stirrup prosthesis: first, the implant is installed in relation to the most damaged ear, and after about six months, stapedoplasty is repeated, but on the other side.

The most widely used is the so-called piston stapedoplasty. This operation does not involve significant damage to the vestibule of the inner ear, so there is no risk of damage to nearby tissues.

Before installing the implant, the window is cleared of mucous and tissues damaged by sclerosis. This is not always necessary, but only if the surgeon has difficulty seeing the area being operated on.

Using a laser device, the doctor makes a hole, inserts the implant into it, and secures it to its natural seat – the long leg of the anvil. The prognosis for the operation will be better if the surgeon makes the hole as small as possible: in this case, the tissues will heal faster, and the rehabilitation period will be significantly easier and shorter.

Most often, stapedectomy and stapedoplasty are performed using a Teflon-cartilaginous implant. Loop elements are cut from a ready-made Teflon analogue, after which cartilaginous plates removed from the auricle are inserted into the holes.

When using a cartilage autoprosthesis, engraftment and recovery occur faster and are less expensive.

Contraindications to the procedure

Stapedectomy will not be performed if the patient has certain contraindications:

• states of decompensation, severe illnesses of the patient;
• hearing problem in only one ear;
• small functional cochlear reserve;
• sensation of ringing and noise in the ears, dizziness;
• active otosclerotic zones.
• if the patient has ongoing balance problems, such as concomitant Meniere's disease with hearing loss of 45 dB or more at 500 Hz and with high-pitched loss.[ 11 ]

Consequences after the procedure

Stapedectomy can effectively treat significant conductive hearing loss associated with otosclerosis by reconstructing the sound-conducting mechanism of the middle ear.[ 12 ] The success rates of these procedures are typically assessed by observing the degree of closure of the patient's air-bone gap (ABG) during audiometric evaluation.

For several days after the stapedectomy operation, the patient may complain of slight discomfort and painful sensations. This condition will continue until the tissues are relatively healed: to ease the condition, the doctor may prescribe painkillers.

A slight noise in the ear is considered a normal variant. It may appear already during stapedectomy and is present until the implant takes root, but most often disappears within about 1-2 weeks. If a strong, increasing noise occurs, it is recommended to consult a doctor: most likely, the stapedectomy will have to be repeated. [ 13 ], [ 14 ]

Among other short-term consequences, the patient may note:

• slight nausea;
• mild dizziness;
• mild pain in the ear when swallowing.

Complications are rare, occurring in less than 10% of cases, and appear approximately one month after stapedectomy. As a rule, the occurrence of complications indicates the need for repeated surgery or drug therapy.

Complications after the procedure

Most often, stapedectomy is performed without any complications, but in some cases, exceptions to the rule are possible. Among the relatively common complications, the most well-known are:

• perforation of the eardrum due to a sharp jump in pressure in the middle ear cavity;
• formation of a fistula in the oval window when the implant moves away from the middle ear bone;
• tissue necrosis (possible when using an artificial implant with synthetic components);
• unilateral facial paralysis on the affected side associated with damage to the branches of the facial nerve;
• postoperative dizziness;
• implant displacement (sometimes occurs when installing Teflon elements);
• nausea, even to the point of vomiting;
• leakage of cerebrospinal fluid from the ear canal;
• mechanical damage to the labyrinth;
• inflammation of the labyrinth.

If severe complications develop, when inflammation spreads to the tissues of the brain and spinal cord, meningitis may develop. The patient is hospitalized, where emergency antibiotic therapy is administered. [ 15 ]

Care after the procedure

After stapedectomy, the patient remains in the hospital under medical supervision for four or five days.

It is possible to administer antibacterial agents, analgesics, and non-steroidal anti-inflammatory drugs.

It is forbidden to blow your nose or to inhale air sharply through your nose. This is due to the following factors:

• The openings of the Eustachian tubes extend to the back surface of the nasopharynx;
• These tubes connect the nasopharyngeal cavity and the middle ear and promote equal pressure between these structures;
• sharp fluctuations in air in the nasopharynx area lead to an increase in pressure and motor activity of the membrane, which can cause displacement of the tissue flap and deterioration of the healing process.

Approximately ten days after discharge, the patient should visit the attending physician for a follow-up examination. Hearing function measurements demonstrate the degree of effectiveness of stapedectomy. Many patients experience a reduction in the air-bone gap, and a decrease in the threshold of sound perception.

It is recommended to measure the hearing function immediately before the patient is discharged from the hospital, then four, twelve weeks, six months and one year after the stapedectomy operation.

Additional safety precautions that a patient who has undergone stapedectomy should take include:

• do not wear headphones to listen to music;
• avoid physical overexertion and sudden movements;
• avoid carrying heavy objects;
• do not smoke, do not drink alcohol;
• do not allow water to enter the affected ear;
• Do not swim, take a bath or visit a sauna for 6 weeks after stapedectomy;
• do not dive (for most patients this restriction remains for life);
• Women who have undergone the procedure are not recommended to become pregnant for 1-2 months after the procedure.

Feedback on the operation

Surgical intervention in the form of stapedectomy is successful in 90% of cases, with no complications. Surgeons warn that the most favorable and rapid healing is observed when installing an autoimplant. Artificial implants sometimes take root poorly, which causes rejection and necrosis.

The quality of restoration of hearing function varies, and depends on a whole host of different factors:

• individual characteristics of patients;
• implant quality;
• qualifications of the operating doctor;
• the presence of conditions necessary for healing.

In the vast majority of operated patients, hearing function improves within the first 3-4 weeks. Significant recovery is observed within three or four months after the intervention.

If all the doctor's recommendations are followed, the majority of patients have a successful stapedectomy and their hearing quality improves.