Types of voice prosthesis
There are two types of voice prosthesis: an indwelling one that is installed and changed by a speech and language pathologist (SLP) or otolaryngologist and a patient-changed one.
The indwelling prosthesis generally lasts a longer time than the patient managed device. However, prosthesis eventually leak mostly because yeast and other microorganisms grow into the silicone leading to incomplete closure of the valve flap. When the valve flap does not close tight anymore, fluids can pass through the voice prosthesis (see below in Causes of voice prosthesis leak section).
An indwelling prosthesis can function well for weeks to months. However, some SLPs believe that it should be changed even when it does not leak after six months because, if left for a longer time, it can lead to dilatation of the puncture.
The patient managed voice prosthesis allows greater degree of independence. It can be changed by the laryngectomee on a regular basis (every 1-2 weeks). Some individuals change the prosthesis only after it starts leaking. The old prosthesis can be cleaned and reused several times.
A number of factors determine an individual's ability to use a patient manged prosthesis:
- The location of the puncture should be easily accessible; the site of the puncture may, however, migrate over time, making it less accessible.
- The laryngectomee should have adequate eyesight and good dexterity, enabling him/her to perform the procedure, and capable of following all the steps involved. An indwelling voice prosthesis does not need to be changed as frequently as a patient managed one.
Two videos made by Steve Staton explain how to replace a patient-changed prosthesis: Prosthesis installation 1 and prosthesis installation 2.
A voice prosthesis (Vegae TM Atos Medical)
Leakage through the voice prosthesis is predominantly due to situations in which the valve can no longer close tightly. This may be due the following: colonization of the valve by fungus; the flap valve may get stuck in the open position; a piece of food, mucus or hair (in those with a fee flap) stuck on the valve; or the device coming in contact with the posterior esophageal wall. Inevitably, all prostheses will fail by leaking through, whether from Candida colonization or simple mechanical failure.
If there is continuing leakage through the prosthesis from the time it is inserted, the problem is generally due to the fact that the flap valve remains open because of negative pressure generated by the swallowing. This can be corrected by using a prosthesis that has a greater resistance. The trade-off is that having such a voice prosthesis may require more effort when speaking. It is nevertheless important to prevent chronic leakage into the lungs.
Leakage around the prosthesis can also occur if the prosthesis is too long for the user’s tract. Whenever this occurs, the voice prosthesis moves back and forth in the tract (pistoning) thereby dilating the tract. The tract should be measured and a prosthesis of more appropriate length should be inserted. In this circumstance leakage should resolve within 48 hours. If the tissue around the prosthesis does not heal around the shaft within this time period, comprehensive medical evaluation is warranted to determine the cause of the problem.
Another cause of leakage around the prosthesis is the presence of narrowing (stricture) of the esophagus. The narrowing of the esophagus forces the laryngectomee to swallow harder, with greater force so that the food/liquid goes through the stricture. The excess swallowing pressure pushes the food/liquid around the prosthesis.
Several procedures have been used to treat persistent leakage around the prosthesis. These include temporary removal of the prosthesis and replacement with a smaller-diameter catheter to encourage spontaneous shrinkage; a purse-string suture around the puncture; injection of gel, collagen or micronized AlloDerm® ( LifeCell, Branchburg, N.J. 08876); cautery with silver nitrate or electocautery; autologous fat transplantation; and inserting a larger prosthesis to stop the leak. Treatment of reflux (the most common cause of leakage) can allow the esophageal tissue to heal.
Increasing the diameter of the prosthesis is generally not recommended. Generally a larger diameter TEP is heavier than a smaller one, and the weakened tissue is often not able to support a bigger device, making the problem even worse.
Some, however, believe that using a larger diameter prosthesis reduces the speaking pressure (larger diameter allows better airflow) which allows greater tissue healing to occur while when the underlying cause (most often reflux) is treated.
The use of a prosthesis using a larger esophageal and/or tracheal flange may be helpful, as the flange acts as a washer to seal the prosthesis against the walls of the esophagus and/or trachea, thus preventing leakage.
The prosthesis may have to be changed if there is an alteration in the quality of the voice especially when the voice becomes weaker or one needs more respiratory effort to speak. This may be due to yeast growth which interferes with the opening of the valve.
- Before using the brush provided by the manufacturer, dip it in a cup of hot water and leave it there for a few seconds.
- Insert the brush into the prosthesis (not too deep) and twist it around a few times to clean the inside of the device.
- Take the brush out and rinse it with hot water and repeat the process 2-3 times until no material is brought out by the brush. Because the brush is dipped in hot water one should be careful not to insert it beyond the voice prosthesis inner valve to avoid traumatizing the esophagus with excessive heat.
- Flush the voice prosthesis twice using the bulb provided by the manufacturer using warm (not hot!) potable water. To avoid damage to the esophagus sip the water first to make sure that the water temperature is not too high.
If the leakage through the voice prosthesis happens within three days after its insertion it may be due to a defective prosthesis or one that was not placed correctly. It takes some time for the yeast to grow. If the prosthesis leaks when new, it is due to another cause. In addition to brushing and flushing with warm water, cautiously rotating the prosthesis a couple of times to dislodge any debris may help. If the leak persists the voice prosthesis should be replaced.
Viscous fluids tend not to leak and consuming them can provide essential liquids despite the leak. Many food items that contain large amount of liquids are more viscous (i.e., jelly, soup, oat meal, toast dipped in milk, yogurt) and are therefore less likely to leak through the prosthesis. On the other hand coffee and carbonated drinks are more likely to leak. Fruits and vegetables (e.g., watermelon, apples etc) contain large amount of water. The way to find out what works is to cautiously try any of these.
The flushing bulb should be introduced into the prosthesis opening while applying slight pressure to completely seal off the opening. The angle that one should place the tip of the bulb varies between individuals. (The SLP can provide instructions how to choose the best angle.) Flushing the prosthesis should be done gently because using too much pressure can lead to splashing of water into the trachea. If flushing with water is problematic, the flush can also be used with air.
- Reduce the consumption of sugars in food and drinks, brush your teeth well after consuming sugary food and/or drinks.
- Brush your teeth well after every meal and especially before going to sleep.
- Diabetic should maintain adequate blood sugar levels.
- Take antibiotics only if they are needed.
- After using an oral suspension of an antifungal agent, wait for 30 minutes to let it work and then brush your teeth. This is because some of these suspensions contain sugar.
- Dip the voice prosthesis brush in a small amount of mycostatin suspension and brush the inner voice prosthesis before going to sleep. (A homemade suspension can be made by dissolving a quarter of a mycostatin tablet in 3-5 cc water). This would leave some of the suspension inside the voice prosthesis The unused suspension should be discarded. Do not place too much mycostatin in the prosthesis to prevent dripping into the trachea. Speaking a few words after placing the suspension will push it towards the inner part of the voice prosthesis.
- Consume probiotics by eating active-culture yogurt and/or a probiotic preparation.
- Gently brush the tongue if it is coated with yeast (white plaques)
- Replace the toothbrush after overcoming a yeast problem to prevent re colonizing with yeasts
- Keep the prosthesis brush clean