Overview of Canine Salivary Mucocele
Salivary mucocele is a condition in which saliva leaks from a damaged salivary gland or duct and collects in the surrounding tissues that can occur in dogs. The condition is also known as sialocele, cervical sialocele, cervical mucocele, ranula, and salivary cyst.
Although trauma is considered to be the usual cause for the damage to the duct or gland, it is rare that a specific traumatic event can be identified. Salivary mucoceles are more common in dogs than cats. Any age and any breed can be affected with this problem.
They cause a soft, usually non-painful, swelling located adjacent to the affected salivary gland. Cervical mucocele is the most common form of this condition and usually show no symptoms except for the swelling under the rear portion of the jaw.
A mucocele under the tongue, called a ranula, is also very common and can cause difficulty chewing or bloody saliva. Less common forms of salivary mucoceles are pharyngeal mucoceles that can cause difficulty swallowing or breathing, and zygomatic mucoceles that occur near the zygomatic cheek bone beneath the eye, which can cause swelling under the eye or problems with the eye itself.
Mucoceles can become infected if not treated, but the prognosis is excellent with treatment.
Diagnosis of Salivary Mucocele in Dogs
Diagnostic tests may include:
Treatment of Salivary Mucocele in Dogs
Treatment may include:
Home Care and Prevention for Salivary Mucocele in Dogs
Inform your veterinarian about any abnormal swelling, whether it appears to be bothering the animal or not. Any difficulty in chewing, swallowing, and especially breathing problems, should be brought to your veterinarian’s attention immediately.
After surgery, watch for potential complications:
Even though trauma is suspected to be the cause for most mucoceles, it is unreasonable to try to avoid all situations that could lead to this problem. The use of choke collars should be limited and the animal should be prevented from chewing on sticks.
Information In-depth for Salivary Mucocele in Dogs
Several salivary glands supply saliva to the mouth to assist with lubrication of the food and begin the process of digestion. Salivary glands are located under the ears, in the back of the mouth, and under the tongue, and the saliva produced within each gland travels through a small duct to get to the oral cavity. Damage to the gland or the duct can lead to leakage of the saliva into the adjacent tissues and create a mucocele. The saliva is mildly irritating to the tissues, and these tissues respond to the irritation by creating a layer of granulation tissue around the pocket of saliva.
Depending on which salivary gland and duct are actually affected and where the resulting swelling occurs, the problem may be given a different name and may cause different symptoms.
The common forms of this condition are:
Blunt trauma is usually suspected as the cause for a mucocele, but rarely is an actual event identified as the cause of the problem. Animals that chew on hard toys or sticks can develop ranulas or pharyngeal mucoceles. Trauma to the neck, as might occur with the use of a choke collar, can result in development of a cervical mucocele.
This problem can occur in any age or breed of dog. Dogs are more frequently affected than cats. Untreated, the salivary mucocele can become infected. With treatment, however, the prognosis is generally excellent for these patients.
Diagnosis In-depth of Salivary Mucocele in Dogs
Simple palpation of the swelling under the neck or under the tongue is often all that is necessary to make the presumptive diagnosis of salivary mucocele. These swellings are soft and feel like fluid within a pocket of tissue. This is unlike the feel of a tumor that might cause a similar swelling in these areas. Tumors usually have a firm, often irregular, feel to them and may be painful to touch.
The definitive diagnosis is made by removal of a sample of the fluid from the swelling and examining it under the microscope. The fluid from a mucocele is usually clear or slightly yellow and thick like mucus. There are usually few cells seen in the sample. Special stains are used to determine if the fluid is saliva. It is important to make sure that the problem is not a pocket of infection (abscess) that might require different treatment.
No other tests are usually necessary to make the diagnosis.
Treatment In-depth for Dogs with Salivary Mucocele
Some veterinarians attempt to treat salivary mucocele with periodic drainage by lancing the swelling and placing a rubber drain within the pocket. This may work in the lucky patient, but for most, the newly created hole quickly seals over after the drain is removed and the swelling occurs again.
The most reliable treatment for these conditions is by surgery.
Follow-up Care for Dogs with Salivary Mucocele
After surgery, some potential minor complications can occur. As with any incision, it can become infected or break open. The incision should be monitored daily for signs of swelling, redness, or discharge. Notify your veterinarian if these occur.
Occasionally, the “permanent” opening into the mouth can completely seal over and a swelling recur. This is not a likely occurrence, but if it happens, the original symptoms can recur.
Sometimes the space from which the mandibular salivary gland was removed fills with other body fluids. This causes another soft swelling called a seroma that usually resolves with time. Your veterinarian may have you applying hot compresses to the area to help the fluid reabsorb.
Frequently, bloody saliva continues for several days after marsupialization of a ranula. You may notice blood in the dog’s water bowl after he drinks. This will usually clear up within a few days, but if it persists or becomes more profuse, contact your veterinarian.