Overview of Round And Oval Window Reinforcement
Hyperacusis is a hearing disorder where individuals have a hard time tolerating everyday sounds that don’t bother most people. If you have hyperacusis, noises that other people may not even notice can cause you discomfort and interfere with your daily life, leading to a lower quality of life.
It’s important to note that hyperacusis isn’t the same as phonophobia, which is a temporary sensitivity to sound that occurs during a migraine and goes away once the migraine is over, or misophonia, which is a strong negative reaction to specific sounds like chewing or breathing.
Hyperacusis isn’t rare – studies suggest that between 5.9% and 17.2% of people may have it. It’s also commonly seen in people who have tinnitus (a condition where a person hears a ringing sensation), with 86% of people having both hyperacusis and tinnitus and 40% of those with tinnitus also having hyperacusis.
To diagnose hyperacusis, doctors mainly rely on patients describing their symptoms, but they may also use tools like the Hyperacusis Questionnaire, the Loudness Discomfort Level test, and the Tinnitus Retraining Therapy interview.
The cause of hyperacusis isn’t completely understood, but there are several theories. One theory suggests that damage to part of the inner ear known as the cochlea or head injuries may cause hyperacusis. Other factors that might be related to hyperacusis include depression, anxiety, reactions to certain medications, hearing loss, and autoimmune disorders (conditions where the body’s immune system mistakenly attacks the body’s own tissues).
There are also other theories about what causes hyperacusis. For example, some researchers think it might be linked to overexposure to sound, which leads to changes in the way the brain processes sound. Other theories suggest that it might be related to changes in serotonin (a chemical in the brain that helps regulate mood), increased opioid levels in the body, or continuous exposure to loud noise (like working in a noisy factory).
There are various treatment options for hyperacusis, including avoiding loud sounds, therapies related to retraining the brain such as tinnitus retraining therapy or cognitive behavioral therapy, and gradual sound exposure therapy. However, there is not a lot of evidence to support these strategies as effective treatments yet. Some new surgical procedures are being explored too, but it’s important to remember that these procedures still need more research.
There’s another symptom related to hyperacusis called autophony. This is when a person hears their own voice or bodily sounds (like pulse, eye movements, and limb movements) as loud or distorted. This is often related to other medical conditions that impact the ears. While some surgical treatments might be able to help with autophony, more research is needed. If you’re suffering from hyperacusis or similar symptoms, it’s important to consult with an ear, nose, and throat (ENT) doctor who can recommend the best course of action based on your unique case.
Anatomy and Physiology of Round And Oval Window Reinforcement
The malleus, incus, and stapes, often referred to as the ossicles, are small bones in the middle ear that help turn the vibrations from our eardrum into sound we can hear. They do this by creating waves in a fluid-filled part of the ear called the cochlea. Each of these bones has different parts, just like larger bones in our body.
Inside our inner ear, we have a maze-like structure made of bone and delicate membranes. This includes the cochlea, which is shaped like a spiral and filled with a fluid. It has two openings into the middle ear, known as the oval and round windows. When sound comes in, it makes the ossicles move, which then moves the oval window. This creates a wave in the fluid inside the cochlea. This wave moves all the way through cochlea and finally reaches the round window, which also moves but in an opposite direction to the oval window. This movement balances the fluid shift inside the cochlea, which helps improve the sound we hear.
As the sound moves through the fluid in the cochlea, it stimulates tiny hair-like cells in a part of the cochlea called the organ of Corti. This opens channels on the cells that let in potassium, triggering nerve signals. These nerves are precisely arranged; nerves close to the oval window are stimulated by high-pitched sounds, and those near the spiral part of the cochlea respond to low-pitched sounds. These signals are then sent to our brain, where they are interpreted as sound.
Why do People Need Round And Oval Window Reinforcement
The aim of a medical procedure known as round and oval window reinforcement for treating hyperacusis, a condition where ordinary sounds seem too loud, is to lessen the energy that the bony structures in your ear (ossicular chain) send to your inner ear. This procedure helps to decrease the movement of fluid within the cochlea, a part of the inner ear, and to improve your results on the Loudness Discomfort Level (LDL) Test, which measures your tolerance to sound.
This strategy has similar goals when used in patients with superior semicircular canal dehiscence (SSCD), a condition which involves a tiny hole in one of the three canals in the inner ear. SSCD often triggers echoing of your own voice (autophony) and other troublesome hearing symptoms. However, the usage of oval and round window reinforcement in these cases is more debated among medical professionals. Still, it is often suggested as the first line of treatment that carries fewer risks for SSCD patients who are not suitable for, or wish to avoid, more complicated procedures.
When a Person Should Avoid Round And Oval Window Reinforcement
There are some reasons why a person might not be able to undergo an operation to strengthen the round and oval windows (small openings) in the ear. These include:
Having an existing infection in the middle ear. This part of the ear is behind the eardrum and contains tiny bones that help in hearing.
Having other illnesses that might make it unsafe to be put under anesthesia, which is the process of putting someone to sleep during an operation.
Being currently diagnosed with anxiety or depression. These are mental health conditions that could affect the patient’s recovery after the operation.
Having Ménière’s disease, a condition of the inner ear that causes problems with hearing and balance.
If the ear that needs the operation is the only ear the patient can hear with, the operation to strengthen the windows is not recommended.
Equipment used for Round And Oval Window Reinforcement
For a procedure to strengthen the oval and round windows in your ear (the parts of the ear that help with hearing), the doctor usually needs the following tools:
An ‘otoscopic microscope’, which helps them see into your ear in great detail. An ‘ear speculum holder’, which helps keep your ear open so the doctor can work. An ‘otologic drill’ fitted with special precise drill bits, one that has 2 diamonds and one that has a single diamond — this helps the doctor work on the fine details in your ear. An ‘otologic instrument tray’ is used to hold all the necessary tools. The doctor may also use ‘biopsy punches’ that are 2 millimeters or 4 millimeters in size. These are used to remove small amounts of tissue for examination
Who is needed to perform Round And Oval Window Reinforcement?
The team usually needed to carry out oval and round reinforcement, a type of ear surgery, consists of:
A main surgeon who is usually a neurotologist (a specialist doctor who focuses on the nerves in your ears) or a knowledgeable general otolaryngologist (a doctor who specializes in treating conditions related to the ears, nose, and throat). The main doctor for your surgery will be quite experienced because this surgery needs a lot of skill.
An anesthesia provider who is responsible for making sure you won’t feel any pain during the surgery. They use medicine to help you sleep, so you won’t be awake or feel anything during the operation.
A surgical technician or operating room nurse who will assist during the operation. Their job is to help the main surgeon and make sure that everything runs smoothly.
A circulating or operating room nurse who moves around the room during surgery, handling any necessary tasks to help the rest of the team.
Preparing for Round And Oval Window Reinforcement
If you’re experiencing hyperacusis, which is an oversensitivity to certain sound frequencies and often a debilitating problem, your doctor will need to run several tests. These checks will include a full medical history review and a comprehensive physical check, focusing on your head, neck, ears and your hearing ability.
In addition to these general examinations, the doctor will also conduct more specialised hearing-related tests, such as a pure-tone audiogram and impedance audiometry. These tests measure the type and extent of your hearing loss. They will also use a type of scanning technology, much like an X-ray, to look closely at the bones in your ears. This scan can help your doctor understand whether there are any abnormalities that may be causing your symptoms.
In some cases, they might test for specific conditions like SSCD (superior semicircular canal dehiscence) or perilymphatic fistulas, that could be contributing to your sensitivity to sound. Doctors can use specialized tests like electrocochleography, and certain muscle potential tests to diagnose these conditions, though these are not always needed.
Your doctor would also assess your sensitivity to loud noises through a questionnaire and a Loudness Discomfort Level (LDL) test. This test identifies the sound level at which noises become uncomfortable for you at various frequencies. Typically, people without hearing problems find noises uncomfortable at around 100 decibels.
Before any surgical treatment, it’s crucial to understand the risks. These can include possible infection, temporary changes in taste, hearing loss (either partial or total), not fully resolving the sensitivity, or even the need for more procedures. You should also be offered alternative options to surgery, like cognitive behavioral therapy or hearing aids, that can help manage the sensitivity to sounds.
How is Round And Oval Window Reinforcement performed
Reinforcing the round and oval windows of the ear is generally a day surgery, which means you don’t need to stay overnight in the hospital. This surgery is done while you are sleep under general anesthesia. During the procedure, a monitor is used to continuously check the facial nerves to avoid any damage. Before the surgery, your ear is cleaned thoroughly to avoid infections.
The surgery is done via an approach called the transmeatal approach which means the surgery is done via the ear canal.
During the transmeatal approach, a small slice is made in the ear canal to open up the area and allow the surgeon to access the part of the ear called the posterior mesotympanum. If needed, additional access can be made. However, extra care is needed to avoid injuries to the nerves.
The next step is to collect a small piece of tissue from the temporalis muscle, located at the side of your head, near your temple. This tissue is then cut into several small parts for use in the procedure.
Once the middle ear is accessible, the surgeon checks the ossicles, the tiny bones inside the ear, to see whether they have any abnormalities and also assesses their mobility. Pieces of the harvested tissue will be then placed onto the round and oval windows in the ear. This helps to reinforce these areas. The ear drum will then be returned to its original position and a piece of absorbable gelatin sponge soaked in antibiotic is placed next to the ear drum to help hold it in place while healing.
Following the surgery, you can go home on the same day, unless there are some exceptional situations like if there were complications during the procedure or if you have other serious health concerns.
About a week after the surgery, you would have to come back to the clinic to check on the healing process. During this visit, the doctor will remove the absorbable sponge from your ear canal. You will also be given a 7 to 14-day course of ear drops to prevent infection after the operation. You will need to have a hearing test about 3 months after the surgery to check the success of the procedure.
Possible Complications of Round And Oval Window Reinforcement
Problems after the procedures to reinforce the oval and round window – two key parts of your ear – are uncommon. But, if they do happen, they can be something like a lasting tear in your eardrum or temporary changes to your sense of taste. Using a respectfully cautious surgical approach, the surgeon can further lessen the already quite small chance of complications after surgery. Such issues could involve the small bone in your ear, called the stapes, moving out of place, severe or total loss of hearing due to nerve damage, harm to the facial nerve, and an unpleasant sense of spinning known as vertigo.
What Else Should I Know About Round And Oval Window Reinforcement?
If you’re someone who’s sensitive to noise, then you might have a condition called hyperacusis. There’s a procedure called ‘oval and round window reinforcement’ which could make a big difference. Studies show that this surgery can help more than 80% of patients tolerate sound better.
Even if you’re experiencing autophony, a condition where you can hear your own voice and bodily sounds more loudly, this procedure can still work, though its benefits might be slightly less. Still, it can be a good option if you’re unable or unwilling to go through more complex surgeries.
