Esophageal reflux and the larynx

There is a seemingly pervasive belief that many or the majority of voice disorders are caused by reflux.The root cause of this current diagnostic epidemic seems due to my colleague's reliance on diagnosing voice disorders solely by looking at the voice box. However, problems with the voice box are nearly always functional in their manifestation and not always easily visualized. In a common scenario, a patient’s complaint of hoarseness is evaluated solely by a visual examination of the larynx. The physician pronounces the voice box “red” or states that there is swelling on the back of the voice box between the vocal cords. A prescription is written for an anti-reflux medication and a dietary and physical regimen such as avoiding caffeine and chocolate, etc. and raising the head of the bed. There are even handouts provided that state a red larynx may be caused by reflux.

Acid reflux or laryngopharyngeal reflux (LPR) are terms used to describe the belief that stomach contents regurgitate frequently back up the esophagus and enter the back of the throat. There is the belief that the lining of the voice box or larynx cannot protect itself from the chemicals or acid present in the stomach and that causes some sort of reaction or burn on the voicebox. Nearly all of us has thrown up at some point and tasted the contents of our stomach. Some of us have heartburn which is frequently attributed to the stomach contents regurgitating up into the esophagus.

So do people regurgitate acid or stomach contents up into their throat frequently? Maybe. If they do, does it cause problems with the voice? Probably no.

Considerations why diagnosing reflux as a cause of hoarseness is error prone

  1. Reflux is frequently an unneeded secondary diagnosis.
    1. Why? Parsimony suggests a simple explanation for hoarseness is sufficient (Occam’s razor)
  2. Redness is a digital artifact. There is nothing red about the larynx.
    1. Inadequate light leads to a perception of redness.
    2. Low resolution and artifact from fiberoptics leads to a perception of redness.
    3. Accurate, detailed images should describe the diameter of vessels, not the quality of redness.
    4. Saying, “The larynx is red” is the same as saying “I had a poor quality view of the larynx.”
  3. Hoarseness is irregular sound production, an impairment of vibration.
    1. lump, pain, cough & clearing are symptoms worthy of separate discussions and are quite likely completely different disorders.
  4. Visible causes of vibratory impairment should be related to
    1. swellings, gaps and stiffness,
    2. Examples include biofilms, edema & scar
    3. Dilated capillaries may lead the examiners eye toward pathology.
  5. Arytenoids and interarytenoid areas are uninteresting from a vocal perspective.
    1. All sound is normally created by the margins of the true vocal cords.
    2. However, in a review paper, many physicians believe, “...laryngeal findings related to LPR are arytenoid and vocal cord erythema, posterior commissure hypertrophy, and arytenoid edema.” (Lechien et al., Clinical outcomes of laryngopharyngeal reflux treatment: A systematic review and meta-analysis. Laryngoscope. 2019 May;129(5):1174-1187. doi: 10.1002/lary.27591. Epub 2018 Dec 30.)
    3. Arytenoids and interarytenoid mucosa are not even an important part of resonance. The pharynx, oral cavity and nasal cavities are the predominant determinant of resonance.
  6. Pitch and volume correlated with roughness & huskiness leads to correct diagnosis.
    1. Understanding sound production, there is no need to make a diagnosis of exclusion in hoarseness.
    2. Lack of a visible lesion is an insufficient reason diagnose reflux laryngitis, LPR, GERD, yet some authors declare clinical response to empirical medical treatment is a reliable alternative approach to confirm the diagnosis of LPRGupta 2016Ford 2005Lechien 2018.
    3. Understanding the mechanics of sound production leads to accurate endoscopy and a correct diagnosis.
  7. Mucus 
    1. Mucus accumulates at vibratory impaired sites. That is, in rapid vibration mucus moves to areas of dampened vibrations. This mucus pointer can be very helpful in the endoscopic search for vibratory impairment.
    2. Mucus is normal.
    3. Mucus accumulation is not sign of reflux, but it often leads the examiner toward phonatory pathology.
  8. Why PPI & H2 blockers seem to work.
    1. Placebo
    2. Thinning secretions.

Parsimony — Reflux is frequently an unneeded secondary diagnosis.

Here is a typical report I have seen in a patient who went to a general otolaryngologist for a complaint of hoarseness.

Laryngoscopy: ...She has distinct vocal cord nodules bilaterally that do not look inflammed. She does have arytenoid edema and erythema that is moderate.

Impression: She has vocal cord nodules and laryngopharyngeal reflux.

Plan: Omeprazole 40 mg twice a day and rest her voice as much as possible...

On my stroboscopy exam there were swellings on the medial margin of the true vocal cords.

Stroboscopy: Open phase

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Stroboscopy: Closed phase

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Color Red — Redness is a digital artifact. There is nothing red about the larynx.

Before we answer these questions, there is the problem that the color red has no impact whatsoever on the function of the voice. The skin (mucosa) lining the vocal tract always appears red or pink – look inside your mouth. In fact the pronouncement of “redness” suggests that the physician has an inadequate view of the vocal cords. Typical fiberoptic endoscopes blur the image of the throat lining with their pixelated view, and a mirror exam of the larynx is so distant that the best that can be seen is often the general sense of the color of the mucosa in the region. However, with newer cameras, the fine detail of the mucosa lining the voice box can be made out. The mucosa is actually translucent and beneath the mucosa can be seen tiny blood vessels. They can be thin, straight, tortuous, dilated, pedunculated, mal-oriented, etc. The vessels themselves are always red from their content (blood) and the more vessels there are, the redder the vocal cords in a hazy image.

Fiberoptic images

 

Digital noise during fiberoptic endoscopy of the vocal cords. These views are in the same patient on the same day. They are taken with a fiberoptic endoscope. The image on the left is taken from above the level of the epiglottis. As the endoscope is moved closer to the larynx in the right image, there is more light reflected back from the larynx into the endoscope. The digital gain is automatically adjusted downward by the camera processor. The false vocal cords look less mottled. Fewer pixels are interpreted by the equipment as red. The same thing happens on your digital phone photos. Nighttime photos may look as good at low resolution as daytime photos, but enlarge the images and all the digital noise becomes apparent in the low-light photos. So to cure reflux laryngitis, move your camera closer to the vocal cords. The redness goes away.

Chip cameras

Here is a comparison of fiberoptic vs chip camera images.

 

These views are in the same patient on the same day. The left image is taken with a fiberoptic endoscope and the right image is taken with a chip-on-tip endoscope. Since the chip is on the tip of the endoscope light does not have to travel through optical fibers before it is processed by the chip, so there is more light available. The digital gain is turned down. There also is no artifact from the fibers themselves. This clearer image suggests there is "less redness." So another way to cure reflux laryngitis is to buy and use better equipment.

Redness & Capillaries

Here is a case of fungal laryngitis treated with fluconazole for one month. 

 

In the left image, if the camera were farther away, the vocal cords might appear "red" to the examiner, but by using a high quality, chip-on-tip endoscope and moving relatively close to the vocal cords, we can see that the cords are not red, but there are very visible or prominent capillaries.

After one month of treatment, the patient's voice is clearer and easier to use. The hoarseness is gone. In the image on the right, after treatment, the capillaries are still present, but much less dilated. The fungus was causing an inflammatory response. It needed more blood supply and the vessels in the left photo were diltated to supply the fungus with the nutrition it needed.

Some additional infomation. You may ask how do I know that fungus was the cause? Since I am just using these two isolated images as a demonstration of blood vessel size, there was actually much more information in the examination of the patient. I moved the endoscope close to the vocal cords, visualized a white biofilm covering some of the vessels. There were isolated, elevated white spots on the margins of the vocal cords at higher magnification, and more details. After treatment, the reduced blood supply, the resolution of the biofilm led to less stiffness of the vocal cord mucose and easier vibration of the vocal cords, hence a clearer voice and the resolution of the sensation of hoarseness. The essence is in a simplistic sense, the left image appears redder than the right. Still, the concept of redness misses the cause of impaired vibration.

Arytenoid edema & Pachydermia

Arytenoids and interarytenoid areas are uninteresting from a vocal perspective. All sound is normally created by the margins of the true vocal cords. Yet, there are physicians who believe that “laryngeal findings related to LPR are arytenoid and vocal cord erythema, posterior commissure hypertrophy, and arytenoid edema.” It is important to note that the physicians who propose this are referring to voice, and yet they often lump other throat symptoms together with hoarseness.

Arytenoids and interarytenoid mucosa are not even an important part of resonance. The pharynx, oral cavity and nasal cavities are the predominant determinant of resonance.

The mucosa in the area between the vocal cords is very loosely attached to the underlying structures (cartilage and muscle). It is loosely attached so that one set of cartilage may move over with minimal restriction. This loose mucosa can swell and change color. It can be smooth and whitish or it can be redundant and floppy, sometimes resembling elephant skin vaguely, and called pachydermia. However, this tissue is not involved in making sound, so it's characteristics and the description of it are generally a diversion from hoarseness.

 

Here is a case of hoarseness. You could say the arytenoids are boggy and red (if you are far enough away).

 

Of course, if the endoscope is moved closer, the appearance of redness goes away. There is also arytenoid pachydermia.

 

Still from a voice perspective, neither the color red vibrates, nor does the interarytenoid area.

 

During stroboscopy, at the pitch where roughness was heard, the vocal cord margins were swollen and irregular.

 

After treatment, the voice cleared and the swelling on the vocal cord margins was reduced.

Listening

I discuss vocal capabilities extensively as a means of orienting a laryngeal examination. Once the pitch and volume combination is identified that creates the greatest vocal impairment, the same combination may be viewed during stroboscopy of the vocal cords.

This retired teacher was told that her "vocal cords were inflammed" and she was treated with prednisone. Still, she was hoarse.

 

This is my exam with a chip endoscope, likely a higher quality view than the general ENT had. Still, I cannot identify any pathology from this viewpoint.

 

A view of her vocal cords during stroboscopy at pitch G4 (relatively high pitch where she has some vocal impairments of air leak and vocal breaks) with a rigid endoscope. Along the medial margin of both vocal cords, on the lower vibratory lip there is a thickening. The left vocal cord (right side of the photo) has the thicker callus (or nodule). By listening to her voice at a range of pitch and volume, I knew her voice was most impaired at high pitch and low volume. I focused my stroboscopy exam on those vocal conditions and the cause of vibratory impairment became visible. Even if she had improved temporarily with the general anti-inflammatory qualities of prednisone, I could not jump to the conclusion clinical response to empirical medical treatment is a reliable alternative approach to confirm the diagnosis of LPRGupta 2016Ford 2005Lechien 2018.

A vocally oriented exam is an accurate exam. There is no need to make use of redness, inflammation, reflux, LPR or GERD as diagnoses of exclusion. 

Mucus

Is mucus a sign of reflux? Mucus is normal. It is the lubricant for vocal cord vibration. However, it does tend to accumulate. The physics of vibration are such that mucus will tend to accumulate at the most dampened portion of vibration. So in essence, it often points the examiner toward the pathology.

This singing teacher attributed her vocal impairment with singing high pitch to bad technique. When I listened, I could hear diplophonia when she was sining above pitch C5. When I looked, on stroboscopy, there was frequently mucus accumulation in the center of her vocal cords.

 

I asked her to clear the mucus a few times (it tends to recur). Then I examined her vocal cords at ultra close range at pitch C5# where I could hear the impairment.

 

From this close view point the important finding are the tiny swellings on each vocal cord. At this pitch, seen here with the mucus cleared, they touch and split the vocal cords into two separate vibratory segments. The front and the back of her vocal cords are vibrating separately and since these segments are different lengths, they generate two distinct pitches simultaneously - diplophonia.

For extra credit, you may notic that the capillaries are not all running parallel to the margin of the vocal cords. Several on each side are tortuous, but generally run stepwise, perpendicular to the vibratory margin. They are a sign of repeated injury to the central vocal cord margin. This is not likely the first time she has experienced vocal difficulties from vocal overuse. Runners injure knees, vocal overdoers injure the central vibratory margin of their vocal cords. 

Her sense of excess mucus, or post nasal drip really is a result not of a problem with the mucus, but of a dampened vibration leading to the accumulation of mucus during vocal use. It is physics in action, not silent reflux in action.

Responds to anti-reflux treatment

12 February 2012: A singer and I ran a little experiment since the singer claimed that reflux medicine have helped his voice a great deal. I saw him three times, and each time I did not know whether he was taking any anti-reflux medication or not. After the three examinations, he revealed to me that he was taking ranitidine (Zantac) for two weeks prior to one of the examinations. The notable finding was that - when he was not taking the medication, his secretions were very thick and sticky. When he was taking the medication ranitidine, an Histamine-2 blocker, his secretions were very thin. I don't know that acid reflux played any role, but it seems that ranitidine, a histamine blocker seemed to thin the secretions.

No ranitidine

 

copious thick mucus

Exam after two weeks of daily ranitidine

 

very little mucus

A later exam when not taking ranitidine

 

The mucus is again thick. I notice that the mucus is spread out over the vocal cords and not significantly impairing his vibrations. However, if he had a vocal swelling or other vibratory impairment, this thick mucus would tend to accumulate at the spot of vibratory dampening and be very noticeable to him.

This might explain why a great many laryngeal disorders seem partially improved, at least for some period of time, with treatment by medications such as ranitidine (Zantac) or a PPI. Whenever there is an impairment of vibration on the vocal cords, secretions will tend to collect at the point of impairment. For example, if there is a nodule or elevation on the vocal cord, secretions will collect at the nodule because the does not vibrate as well at the nodule. Similarly, bowed vocal cords will tend to collect secretions at either end. Consequently, the thinning of secretions would lead to less stickiness at the ends of the vocal cords.

If you have hoarseness and have seen an ENT...

I have seen over 15,000 voice patients. A majority of the patients that I see for vocal troubles who have already seen an ENT are already being treated for reflux with a medication called a proton pump inhibitor {eg: Omeprazole (brand names: Losec®, Prilosec®) Lansoprazole (brand names: Prevacid®, Zoton®, Inhibitol®) Esomeprazole (brand names: Nexium®) Pantoprazole (brand names: Protonix®, Somac®, Pantoloc®) Rabeprazole (brand names: Rabecid®, Aciphex®, Pariet®)} or an H2 blocker {eg: Cimetidine (brand name: Tagament®, Ranitidine (brand name: Zantac®)}.

So, if you have been diagnosed with reflux as the cause of your vocal disorder and especially if you are not improving, it is not likely that you need more of the medication or that you need an anti-reflux surgery to fix your hoarse voice. It is quite likely that you need a more precise diagnosis. 

Dr. Zubiaur and I published a review of how often I see the diagnosis of reflux laryngitis when it is not the cause of a voice disorder:

Thomas, J.P. & Zubiaur, F.M., Over-diagnosis of laryngopharyngeal reflux as the cause of hoarseness Eur Arch Otorhinolaryngol (2013) 270: 995

21 June 2010: See also slate.com article on over-medication by doctors with anti-reflux medication - The Reflex To Treat Reflux