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Affection of salivary gland

Dr. Bikash PuriAssist. Professor

Nepal Polytechnic Institute, Chitwan

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Mucoceles (Salivary cysts)• Salivary mucocele (or sialocele) is an accumulation of saliva in the submucosal or

subcutaneous tissues after damage to the salivary duct or gland capsule.

• This is the most common salivary gland disorder of dogs.

• Although any of the salivary glands may be affected, the ducts of the sublingual and

mandibular glands are involved most commonly.

• Saliva often collects in the intermandibular or cranial cervical area (cervical

mucocele).

• It can also collect in the sublingual tissues on the floor of the mouth (sublingual

mucocele or ranula).

• A less common site is in the pharyngeal wall (pharyngeal mucocele) or lower eyelid

(zygomatic mucocele).

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Cervical mucocele

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Ranula

A ranula is a thin walled linear swelling that results from ruptured sublingual or

mandibular salivary ducts below the oral mucosa next to the tongue or rupture of the

polystomatic portion of the sublingual gland.. Rannulas have been reported in cats.

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Causes• Usually, the exact cause is not determined, but a developmental

predisposition in dogs has been suggested

• Traumatic injury

• Blockage

• Rupture of the duct or capsule (with damage of parenchyma) of the

sublingual, mandibular, parotid, or zygomatic salivary gland.

Note: the leakage of the salia into the surrounding tissue and their reaction

with local tissue may lead to development of salivary cyst or ranula.

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Signs• A mucocele is detectable as a soft, fluctuant, painless mass

• Pain or fever may be present if the mucocele becomes infected.

• On aspiration of light brown or blood-tinged, viscous saliva can be detected.

• Usually, careful palpation with the animal in dorsal recumbency can determine

the affected side;

• if not, sialography may be helpful.

• .

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• A ranula may not be seen until it is traumatized and

bleeds.

• A pharyngeal mucocele can obstruct the airways and

result in moderate to severe respiratory distress.

• A zygomatic mucocele may result in exophthalmos or

enophthalmos, depending on its size and location

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Treatment• Ranula

– Incise the cyst to drain out the contents .

– Cyst wall is then touched with Tinct. Iodine to destroy its lining and

prevent further accumulation of fluid.

– Finally, suture the mucous membrane of the ranula to the oral

mucosa. Use a multfilament synthetic absorbable suture of 3-0 size.

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Surgical technique (Cervical Mucocele)

•  Removal of the mandibular and sublingual salivary glands

• First positioning the dog in lateral recumbency with the affected side uppermost.

•  The neck and jaw should be positioned slightly obliquely and towels or sand

bags placed under the neck to elevate the surgical site for better visualization of

the bifurcation of the jugular vein.

•   The incision is made from the ramus of the mandible cranially to the

bifurcation of the jugular vein caudally  ; occlusion of the jugular vein prior to

incision will facilitate visualization of landmarks.  Dissection is carried into the

capsule of the mandibular and sublingual salivary glands.  An intracapsular dis

section commences and the glands are removed from the capsule.

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• The ducts of the mandibular and sublingual salivary glands are followed cranio medially to the

mandible. 

• If you are on the correct side, you should encounter saliva from the mucocele oozing into the incision or

a dilation of the duct can be visualized.

• The ducts are followed as far cranially as possible and ligated or stripped out to complete the resection 

An incision is made at the most dependant point of the cervical mucocele (when the animal is standing!)

and a penrose drain is placed to facilitate postoperative drainage of saliva  Platisma muscle,

subcutaneous tissues and skin are closed in a routine fashion and 

• The drain is removed two to three days postopera tively. If the salivary glandular tissue has an unusual

appear ance at the time of resection, it should be submitted for histopathologic eval uation.

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Salivary fistula• Salivary fistula is an uncommon problem that can result from trauma

to the mandibular, zygomatic, or sublingual salivary glands.

• Wounds of the parotid gland are most likely to develop a fistula.

• Parotid duct injury may be the result of a traumatic wound (eg, bite

wound), abscess drainage, or prior surgery in the area with

iatrogenic rupture.

• The constant flow of saliva prevents healing, and a fistula develops.

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Clinical signs

• Saliva dribbles down form the wound causing excoriation in the area.

• Losses of excessive saliva may lead to dehydration and ingestion

• Presence of high grade of inflammation sometime it lead to inflammation to parotid gland itself.

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Treatment• After proper controlling and achieving anaesthesia, a circular

incision should be made along the fistular tract.• Care should be taken not to cut facial artery and vein• The stenson’s duct is isolated. Due to pressure of accumulated

saliva in duct, diameter becomes many times larger than normal.• The blunt needle or catheter is passed inside the duct toward s

the glandular part• A counter irritant solution is injected inside the duct to destroy

the function of the gland.• The duct is ligated after withdrawing the catheter or needle• The wound is debrided and closed in routine manner.

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Excision of the parotid gland

• It is indicated only when there is high grade of infection.

• For this, an oblique incision of 15-20 cm is given bellow the base of the

ear extending along the caudal border of the vertical ramus

• The parotid gland is ligated or clamped

• The skin and parotido-auricularis muscle are reflected to expose the gland.

• The duct along with infected gland should be removed intact to avoid

contamination of the area.

• Provide drainage and the skin wound closed in routine manner.