Cricopharyngeal Achalasia in Dogs

Cricopharyngeal dysphagia is divided into achalasia and asynchrony, which is an abnormal timing of the opening of the esophageal sphincter. Asynchrony can happen in conjunction with achalasia. It is important to differentiate true achalasia from other causes of dysphagia in diagnosis, as treatments will vary based on the real problem. True achalasia is treatable with surgery, but it is often not recommended if other underlying conditions exist.

Cricopharyngeal achalasia is a rare disorder that causes dysphagia, or the inability to swallow. This form of cricopharyngeal dysphagia occurs when the esophageal sphincter, or the cricopharyngeal muscle, is unable to relax and open, creating an inability to pass food through the muscle. This is an extremely dangerous condition resulting in malnourishment and aspiration pneumonia, a lung infection caused by inhaling food or liquids into the lungs. Achalasia can be a life-threatening condition if not treated.

Symptoms of this condition are most often seen in young dogs as they are weaned onto solid foods. In the rare case, achalasia can affect older dogs. Symptoms include:

• Inability to swallow
• Gagging
• Regurgitation
• Vomiting
• Repeated swallowing attempts
• Aspiration
• Coughing
• Bloating
• Lethargy
• Inability to gain weight
• Emaciation
• Pneumonia due to aspiration

The true cause for older animals is unknown, but it may be related to other disorders. The current accepted causes of cricopharyngeal achalasia are: 

• Congenital abnormalities of the upper esophageal sphincter
• Acquired neuromuscular disorders
• Breed predisposition (Golden Retrievers, Cocker Spaniels, Springer Spaniels)

Disorders leading to dysphagia are common in dogs, and a full physical exam will be performed to assess the extent of the problem. The inability to swallow can be caused by an issue with the swallowing reflex, or from an injury, tumor or foreign body, so be sure to relate any symptoms or incidences to your veterinarian. It is highly important to correctly diagnose the true cause, and to note any secondary symptoms that need immediate treatment. The diagnosis will take into account congenital issues, any history of anesthesia and other drugs, signs of neuromuscular disease, and the results of testing.

An examination of the pharynx is conducted and sometimes requires sedation. The pharynx and neck are checked for any masses, pain or asymmetry. X-rays may be taken to determine the size of the pharynx. The chest is checked for signs of pneumonia. 

Video fluoroscopic evaluation of the swallowing muscles is routinely done if achalasia is suspected. This involves administering liquid barium, alone or with food, to observe the internal muscles as your dog eats and drinks. Other testing methods can include esophageal pH testing, an EMG, an esophagoscopy to look at the esophagus internally, and an esophageal manometry to measure the lower esophageal sphincter function.

Treatment and support for malnourishment and aspiration pneumonia, as well as any other secondary conditions that may have arisen, need to be addressed immediately. Your dog needs to be well hydrated and nourished before any surgery is undertaken.

Surgery

Treatment for true achalasia is generally surgery. A thyropharyngeal and cricopharyngeal myotomy is a surgical sectioning of the upper esophageal sphincter, or cricopharyngeus muscle, and often includes excising thickened tissues in those muscles. This usually results in a return to normal swallowing following surgery, with a success rate of 65%. In cases where the dysphagia doesn’t seem to respond and there is an absence of any other neuromuscular disease, a repeat of surgery on the opposite side may be effective, but is rare. In cases where aspiration pneumonia is present, surgery can worsen this condition and may not be recommended.

Other Treatments

Adult dogs who have neuromuscular disorders respond better to treatment of the underlying disorder, and generally don’t respond as well to surgery. In some cases, a stomach feeding tube may be recommended, especially when other diseases are involved or if the true cause of the dysphagia is yet to be determined. Feeding practices may also be used as treatment.

Another non-surgical treatment involves injecting a botulinum toxin into the cricopharyngeus muscle to weaken the contraction. Recovery generally lasts for 2 to 4 months, and can be reapplied if needed. Success or failure of this treatment can be a sign of how well surgery will go, and is often used before surgery is undertaken. Aspiration pneumonia needs to be treated as well, and the patient should be stabilized for a better rate of success.

Surgical success is variable. Dogs can either recover completely, have a reoccurrence within 12 weeks, have a partial recovery, or show no improvement whatsoever. 

If surgery is performed, it is generally recommended to feed your dog soft foods for 1 to 2 days afterward, slowly returning him to normal foods during the course of the next 2 to 3 weeks. If your dog is still unable to swallow after 2 to 3 days from surgery, contact your veterinarian, as the achalasia probably wasn’t corrected. Further treatment and supportive care may be needed.

In about 50% of cases, complications following surgery involved aspiration pneumonia, malnutrition, and recurrent dysphagia. Depending on any secondary conditions your dog may have, such as pneumonia, medications and further care may be prescribed.