Cricopharyngeal achalasia in dogs is a relatively rare but serious swallowing disorder that affects all breeds and ages but is more common in younger dogs. It occurs when the cricopharyngeal muscle, located at the upper part of the esophagus, fails to relax properly during swallowing, leading to difficulties in passing food from the mouth to the stomach. Although often overlooked or misdiagnosed, this condition can have a significant impact on a dog's health and quality of life, making it crucial for pet owners and veterinarians to be well-informed about its symptoms, diagnosis, and management.

What is cricopharyngeal achalasia?

Cricopharyngeal achalasia is a swallowing disorder defined by irregularities in the upper esophageal sphincter's function. Cricopharyngeal achalasia in dogs is a structural variant of dysphagia, characterized by the cricopharyngeus muscle's inability to relax during swallowing. This malfunction prevents the upper esophageal sphincter from opening, obstructing the passage of food into the proximal esophagus.

What causes cricopharyngeal achalasia in dogs?

Cricopharyngeal achalasia is thought to be a congenital neuromuscular motility disorder, although its precise cause remains unclear. Conditions associated with cricopharyngeal achalasia in dogs can include myositis, myasthenia gravis, hypothyroidism, and various neuropathies or myopathies.

What are the symptoms of cricopharyngeal achalasia in dogs?

Clinical signs and physical abnormalities of cricopharyngeal achalasia in dogs may include:

  • Gagging
  • Retching
  • Repeated swallowing
  • Dysphagia (difficulty swallowing)
  • Oral or nasal regurgitation
  • Failure to gain weight
  • Ravenous appetite

How is cricopharyngeal achalasia diagnosed in dogs?

For dog owners seeking a diagnosis of cricopharyngeal achalasia, video fluoroscopy is a crucial diagnostic tool. This real-time, dynamic X-ray procedure enables veterinarians to visualize the swallowing process in action, providing insights into the function of the upper esophageal sphincter. By observing the movement, they can determine if the cricopharyngeus muscle is relaxing properly during swallowing, which is essential for an accurate diagnosis and the development of an effective treatment plan.

Additionally, blood tests to investigate the causes of cricopharyngeal achalasia are also recommended. These tests may include a CBC, biochemical profile, thyroid testing and myasthenia gravis (AchR) titres.

In the interest of ruling out other causes of the symptoms, a sedated exam to visualize and evaluate the throat region is a good idea and may be recommended by your veterinarian.

How is cricopharyngeal achalasia treated in dogs?

The mainstay of treatment for cricopharyngeal achalasia in dogs is to restore the normal function of the cricopharyngeus muscle. This often requires surgery, which can involve either cutting the muscle or removing it altogether to allow the upper esophageal sphincter to open more easily during swallowing, facilitating the passage of food into the esophagus.

If the dog is unable to maintain proper nutrition due to severe dysphagia, a temporary or permanent feeding tube may be placed directly into the stomach or esophagus. This allows the dog to receive the necessary nutrients while bypassing the affected swallowing mechanism.

In some cases, dogs with cricopharyngeal achalasia have been treated with botulinum toxin injections to offer temporary relief. Botulinum toxin works by weakening the muscle's contraction when injected, as it blocks the release of a chemical called acetylcholine, which is responsible for muscle movement. By injecting this substance into the cricopharyngeus muscle, it can help improve the swallowing process for about 2-4 months. This treatment is not a permanent solution, but it can provide some relief for dogs suffering from this condition.

What is the prognosis for dogs with cricopharyngeal achalasia?

The outlook following surgery can be positive for many patients; however, it is important to note that not all dogs experience a favourable outcome.

As aspiration pneumonia is a common sequela of cricopharyngeal achalasia in dogs, this can affect the prognosis as left untreated, aspiration pneumonia can be fatal. If you notice coughing, nasal discharge, and/or abnormal or laboured breathing, please contact your veterinarian right away.

Cricopharyngeal achalasia is an uncommon condition in dogs that can cause difficulty with swallowing. While the exact cause remains unclear, it is important to be aware of the symptoms and contact your veterinarian if any are observed. Diagnosis requires video fluoroscopy as well as blood tests to investigate potential causes, while treatment typically involves surgery or botulinum toxin injections for temporary relief. The prognosis after surgical intervention depends on each individual case but can often be positive; however, aspiration pneumonia should also be kept in mind due to its potentially fatal outcome if left untreated. It's essential that pet owners monitor their dog’s health closely and consult their vet when necessary so they can provide them with timely care when needed. If you are concerned that your dog has cricopharyngeal achalasia, please contact your veterinarian.