Salivary Mucocele in Dogs

Canines have salivary glands under their tongues and in the back of their mouths.  Salivary glands produce saliva, which then goes through a salivary duct to the mouth, where it helps with the digestion process.  If a gland or duct gets damaged, saliva leaks into surrounding tissue and collects. Mucoceles are typically soft and non-painful, unless a secondary bacterial infection is present. Pharyngeal mucocele can make it difficult for the canine to breathe or swallow.

Salivary mucocele can develop into a major problem because the saliva is being constantly produced and the body is unable to reabsorb it all. The area where the saliva is being collected continues to grow and may form cysts. The problem will not just go away, you must take your pet to the veterinarian. The longer you wait, the more difficult it will be for your veterinarian to determine which salivary gland has ruptured.  

All breeds are susceptible to mucocele but there is an increased incidence in German Shepherds, Australian Silky Terriers, Poodles, and Dachshunds. Mucocele has no age predisposition; young or older dogs may develop the condition.

A salivary mucocele occurs when a collection of saliva leaks from a canine’s damaged salivary gland or salivary duct and collects in the surrounding tissues. This condition causes painless swelling of the neck or within the oral cavity.

Salivary mucocele may include one or more of the following symptoms:

• Swelling of the neck
• Swelling under the tongue
• Difficult swallowing
• Breathing difficulties
• Secondary bacterial infections
• Fever if there is a bacterial infection
• Blood in saliva

Types 

• Cervical mucocele - This is the most common type of mucocele; the saliva collects in the upper neck region, under the jaw, or in between the jaw
• Ranula mucocele - Another common location for the formation of a mucocele; the saliva collects beneath the tongue alongside the tongue 
• Zygomatic mucocele - Is a rare type of mucocele; the saliva collects around the eye 
• Pharyngeal mucocele - This type of mucocele is also less common; the saliva collects mostly in the back of the throat

Usually, the exact cause is not usually determined, but there are certain breeds that show predisposition.  Additional causes may be:

• Trauma from choke collars
• Bite wounds
• Sudden hyperextension of the neck

Your veterinarian will go over your pet’s medical history and he will ask you when the swelling first started.  During the physical examination your veterinarian will gently palpate the area.  Usually mucoceles are easily identified; tumors and abscesses may appear similar but are generally firm and painful. Your veterinarian may recommend a sterile aspiration of the fluid in the mass. In mucocele the aspiration will be a clear blood tinged thick ropy fluid. The aspirated fluid will also be examined under the microscope. High white blood cell count in the fluid may indicate an infection in the salivary gland or an abscess.

Your veterinarian team will need to perform surgery to find the ruptured duct.  To make sure your pet is healthy and can undergo surgery, a complete blood work (CBC), urine test, and chemistry profile will be recommended.

The only suitable treatment for salivary mucocele is surgery to remove the ruptured gland or glands involved. Aspiration or draining of the mass will only resolve the problem for a short amount of time.  

Ranulas, cervical and pharyngeal mucoceles are all treated by surgical removal of the mandibular and sublingual glands of the affected side. A zygomatic mucocele means the gland needs to be removed from beneath the eye.

Following surgery your pet will receive pain medication; the veterinarian will prescribe nonsteroidal anti-inflammatories, local anesthetics, and narcotics to control the pain.  Most patients can go home on the same day as the surgery.  If the surgery was more complicated, your pet may need to remain hospitalized overnight. Once your pet is home, he can’t be allowed to scratch at the incision; the use of an Elizabethan collar will be necessary. Movement and exercise is usually restricted for about 3 weeks after surgery.  Follow-up visits will be necessary to check the incision and for the removal of the drain. Make sure to call your veterinarian if your pet experiences breathing difficulties, if there is swelling or bleeding of the incision.

The prognosis following surgery is very good. Removal of a set of salivary glands will not alter your pet’s salivary function, the other glands will take over the work. The recurrence of the mucocele is very uncommon.