Contents
Disclaimer
Disclaimer: R-CPD is not yet a widely recognised condition. Unlike most other articles on almostadoctor, there is not a large evidence base to back-up the recognition and treatment of this disorder. As a newly described disorder, many of the facts and features are not yet fully understood, nor treatments proven. However, as the author is a sufferer of this disorder, he wishes to educate current and future medical practitioners about the condition in a bid that it may become more widely recognised and treated. To learn more, you can read the blog post about his experiences of living with the condition.
Introduction
Retrograde Cricopharyngeus Dysfunction (R-CPD) describes a disorder where the cricophayrngeus muscle (sometimes referred to as the Upper Oesophageal Sphincter) fails to relax to allow the upward passage of gas, and thus results in an inability to burp (belch).
It is thought to start at an early childhood age, but usually presents in early adulthood (families may or may not recall an ability to burp as an infant). Symptoms can vary from mild to incapacitating, and may include chest and epigastric pain, excessive bloating and flatulence, gastro-oesophageal reflux, loud gurgling sounds heard from the chest and neck and sensations of pressure in the neck and chest.
Current recommended treatment is a botox injection into the cricopharynxgeus muscle. This is typically performed under general anaesthetic by an ENT surgeon. Anecdotally, some patients report that neck muscle strengthening exercises over several weeks can help them to develop the ability to burp. Once the ability to burp is achieved from either method, symptoms resolve. The efficacy of the botox treatment in most patients appears to be much longer than the duration of action of botox itself, and may be permanently curative. This suggests that perhaps there is a change in neurological control of the cricopharyngeus muscle in response to botox procedure – patients “learn” how to burp.
Epidemiology and Aetiology
- Completely unknown
Pathology
The cricopharyngeus muscle lies around the top of the oesophagus, and arises from the cricoid cartilage, and attaches to the posterior medial line of the pharynx. The lower part of the muscle is continuous with the fibres of the oesophagus.
It it sometimes described as the “lower part” of the inferior pharyngeal constrictor muscle.
- It is also known as the upper oesophageal sphincter (UES)
The muscle is not under conscious control. On swallowing, relaxation is initiated by the arrival of a food bolus into the pharynx. This is known as the anterograde action.
On the action of belching, pressure in the upper oesophagus should cause relaxation to allow the gas bolus to be released. This is known as the retrograde action.
In R-CPD, the anterograde function is unaffected, it is only the retrograde action that is dysfunctional; hence the terminology – retrograde cricopharyngeal dysfunction. This differentiates it from the neurological disorder cricopharyngeal dysfunction which typically presents with difficulties swallowing.
Presentation
Patients with the condition are described as ‘miserable’. In many cases it may be mild, but in those presenting to General Practice, ENT or gastroenterology, symptoms are usually more severe. Patients describe:
- A sensation of pressure in the chest or neck – as if gas is sitting in the oesophagus. They often describe the sensation of gas travelling up and down the oesophagus, as though it is unable to escape when it reaches the top.
- This is often accompanied by loud gurgling sounds, frequently with vivid and imaginative descriptions – such as “velociraptor noises”
- These can cause significant social discomfort and social situation avoidance for some patients
- Chest pain
- Occasionally may be so severe as to cause presentation to the emergency department
- Severe symptoms are often short lived (hours) as the gas soon passes through the digestive tract
- Epigastric pain
- Excessive abdominal bloating
- Typically progressive throughout the day
- Often the patient describes a flat stomach in the morning and a very distended abdomen in the evening
- Presumably relieved by flatulence overnight!
- Excessive flatulence
- Often associated with GORD
- R-CPD appears to be sometimes misdiagnosed as GORD. Be wary of R-CPD in otherwise young, well patients with GORD that fails to respond to treatment
- Symptoms exaggerated by ingestion of gas – such as carbonated drinks, and strenuous physical exercise (which can result in aerophagia)
- Perhaps the severity of the disorder is related to the degree of natural aerophagia that occurs in any given individual – those who have a tendency to swallow more air when eating and drinking might be more likely to experience symptoms due to large volumes of gas ingested.
- Painful hiccups
- Sensation of difficulty breathing when “full of air”
- Difficulty vomiting (some patients only)
- Patient report that they have never vomited, or only a handful of times in their life
- They may have a fear of vomiting
Patients have often had symptoms for many years and may have seen several other medical professionals, often without explanation for their symptoms. They can often be disheartened with the medical profession and may have been dismissed off-hand.
Suggested diagnostic criteria
Consider referring patients to ENT for suspected R-CPD when all four of 4 of the following are present:
- Inability to burp (belch)
- Gurgling sounds in neck or chest
- Sensation of pressure in chest OR abdominal bloating
- Excessive flatulence
Differential diagnosis
- GORD
- IBS
Be wary of diagnosing either of the above conditions in a patient who describes an inability to burp, as it is the inability to burp that is possibly the (treatable) cause. Treatments for GORD and IBS will typically be ineffective if trialed.
- Cricopharyngeal dysfunction
- A neurological disorder than typically presents with swallowing difficulties. Is often treated with the same botox injection suggested for R-CPD
Investigations
- Video laryngoscopy
- Performed with an awake patient in the ENT clinic rooms
- Local anaesthetic is applied
- Video laryngoscope passed through the nose to view the vocal cords and upper oesophagus
- Tongue, pharynx and pharynx are examined
- Swallowing tests performed to ensure that the cricopharynxgeus muscle works correctly in a swallowing motion (anterograde) but not a retrograde (backwards) direction
- Typically diagnostic and it shows there is no relaxation of the cricopharynxgeus with oesophageal pressure
- Patients may also be noted to have a ‘floppy’, distended oesophagus distal to the cricopharynxgeus muscle
- CXR or CT of chest +/- abdomen
- May show a large gastric bubble (and usually does if there is an acute presentation associated with chest pain)
- Is not diagnostic
Management
There is a single, small, single centre published study describing the use of botox to treat the disorder.
Botox
- Botox into the cricopharynxgeus muscle
- Doses of 50-100 mouse units (MU) have been described
- Typically performed under general anaesthetic with video laryngoscopy
- Botox should be injected into all 4 quadrants of the muscle
- Botox itself typically wears off after 3 months – HOWEVER – the majority of patients seem to “learn” the ability to burp, and retain this skill after the botox has worn off
- The study suggests that 60% of patients remain burpers after one attempt at botox, 90% after 2 and 100% after 3 attempts.
- It takes 2-3 days for the botox to begin paralysing the muscle and up to 2 weeks for it to reach its maximum effect, and thus the benefits are not immediate
- There may be a temporary difficulty in swallowing – especially solids (meat and bread in particular) as the botox begins to work. This usually lasts less than a few weeks.
An alternative method of injection into the cricopharygeus exists. This is performed percutaneously, usually with EMG guidance, and can be performed on an awake patient. It it appears this method may be less effective.
Laser myotomy
A more permanent solution is a laser myotomy (irreversible), which should be reserved for resistant cases. In this procedure, a laser is user to burn through the posterior portion of the cricopharyngeus. The only published paper on this procedure for this indication suggests using a “partial” myotomy – leaving 20% of the fibres intact – in an attempt to reduce complications. This is a somewhat unorthodox approach as typically cricopharyngeal myotomies are complete, due to the risk of recurrence in partial procedures.
Physiotherapy
Many patients report anecdotally that neck strengthening exercises have given them the ability to burp (no proven published evidence).
Suggested exercises include:
- “Shaker exercise” – the patient lies on their back on a bed, with their head protruding over the end of the bed. Against gravity, the patient raises the head to the horizontal position and holds it there for 1 minute. Repeat x3 sets with one minute between, daily
- “Chin to chest” – whilst lying in the same position as described above, perform 30 repetitions of chin-to-chest. x3 sets, daily
Patient support group
There is a large online community of “no burpers” on reddit. You may wish to refer patients here to discuss their experiences with others.
References
- Inability to Belch and Associated Symptoms Due to Retrograde Cricopharyngeus Dysfunction: Diagnosis and Treatment.OTO Open. 2019 Jan-Mar; 3(1): 2473974X19834553. Published online 2019 Mar 15. Robert W. Bastian, MD1 and Melissa L. Smithson, MS.
- Laryngopedia – Inability to burp
- Partial Cricopharyngeal Myotomy for Treatment of Retrograde Cricopharyngeal Dysfunction – Robert W. Bastian MD, Rebecca C. Hoesli, MD