Page 45 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

• Zygomatic sialoceles are infrequently reported in dogs. Postoperative pain control is achieved with methadone,
The clinical signs of zygomatic sialocele and neoplasia oxymorphone, hydromorphone, butorphanol, buprenor-
VetBooks.ir presenting clinical sign. Secondary ophthalmic signs steroidal anti-inflammatory drugs can be used for pain
phine, tramadol and transdermal fentanyl patches. Non-
are similar. A visible periorbital mass is usually the
management following less involved surgical procedures.
depend on the location and size of the sialocele (e.g.
exophthalmos). Additional signs, such as osteolytic
changes of the zygomatic arch and enlargement of the
mandibular lymph node, may accompany neoplasia Antimicrobial therapy
originating in the zygomatic gland. Antibiotic treatment is usually not required after oral and
oropharyngeal surgeries in the otherwise healthy patient.
Diagnosis Broad-spectrum antibiotics (e.g. amoxicillin, clavulanate-
potentiated amoxicillin, clindamycin, cefazolin, spiramycin/
The diagnosis is based on clinical signs, history and the
results of paracentesis. Sialocele paracentesis reveals a metronidazole) are given perioperatively to debilitated and
stringy, sometimes blood-tinged, fluid with low cell num- immunosuppressed patients and those suffering from
bers. Mucin and amylase analyses of the fluid are not organ disease, endocrine disorders, cardiovascular disease,
reliable diagnostic procedures. severely contaminated wounds and systemic infections.
A chronic cervical sialocele may contain palpable firm
nodules that are remnants of sloughed inflammatory Nutritional support
tissue previously lining the sialocele. Sialoliths are concre-
tions of calcium phosphate or calcium carbonate and may Oral intake may not be permitted during the first few hours
occur with a chronic sialocele. Physical examination and following surgery (except in paediatric patients who are at
history usually denote the origin of the sialocele. Cervical risk of hypoglycaemia). Hydration may be maintained
sialoceles that appear on the midline usually shift to the with intravenous fluids. Water is offered once the animal
originating side when the patient is placed in exact dorsal has recovered from anaesthesia. Soft food is offered
recumbency. 12–24 hours after surgery and maintained for about 2
Sialography can be used to determine the affected side weeks. Most dogs and cats will eat and drink even after
if observation and palpation are unsuccessful. Sialography major oral surgery. However, some animals may refuse
is also a diagnostic aid when considering traumatic injury any oral intake. The owner is then instructed in syringe
to one of the salivary glands, salivary neoplasia, fistulous feeding of a liquid, high-caloric diet. Rarely, naso-oesoph-
tract of unknown origin or a foreign body in the head or ageal, oesophageal or gastrostomy tubes are needed to
neck. The disadvantages of sialography include the need bypass the oral cavity.
for general anaesthesia and the difficulty associated with
locating the duct opening(s).
Wound management
Treatment Dilute chlorhexidine solution or gel is administered into the
mouth for 1–2 weeks. A major complication after oral
Surgical removal of the zygomatic gland is indicated for surgery is wound dehiscence, usually as a result of tension
sialoceles of zygomatic gland origin. Various approaches on suture lines or compromised vascularity of flaps. Eliza-
have been used to treat cervical sialoceles. Sialocele drain- bethan collars, tape muzzles, soft muzzles or other restrain-
age, removal of the sialocele only, and chemical cau teri- ing devices may be used for some animals to prevent
zation have been reported. The basis for these therapies disruption of the surgical site. A re-examination is per-
was the belief that a sialocele was a true cyst with a formed in 10–14 days for removal of skin sutures.
secretory lining. Recognition of the fact that a sialocele is
a non-cystic reactive encapsulating structure has prompted
surgical removal of the affected gland–duct complex.
The intimate anatomical association of the sublingual References and further reading
and mandibular salivary glands and their ducts requires
resection of both structures by a lateral approach (see Arzi B and Verstraete FJM (2012) Clinical staging and biopsy of maxillofacial
Operative Technique 3.6) if either of them is believed to be tumors. In: Oral and Maxillofacial Surgery in Dogs and Cats, ed. FJM Verstraete
and MJ Lommer, pp. 373–486. Saunders Elsevier, Edinburgh
the origin of the sialocele. Although a ventral approach has Bonner SE, Reiter AM and Lewis JR (2012) Orofacial manifestations of high-rise
been described (Marsh and Adin, 2013), the authors con- syndrome: a retrospective study of 84 cats (2000–2010). Journal of Veterinary
sider the lateral approach to provide better overall expo- Dentistry 29, 10–18
sure for the procedure. Another technique for treating Ciekot PA, Powers BE, Withrow SJ et al. (1994) Histologically low-grade, yet
biologically high-grade, fibrosarcomas of the mandible and maxilla in dogs:
sialoceles involves marsupialization. However, resective cases (1982–1991). Journal of the American Veterinary Medical Association 204,
surgery is preferred for pharyngeal sialoceles because life- 610–615
threatening upper airway compromise and morbidity from Culp WT, Ehrhart N, Withrow SJ et al. (2013) Results of surgical excision and
evaluation of factors associated with survival time in dogs with lingual
swallowing dysfunction (e.g. aspiration pneumonia) are neoplasia: 97 cases (1995–2008). Journal of the American Veterinary Medical
potential complications of conservative management or Association 242, 1392–1397
recurrence (Lewis and Reiter, 2011). owler D ( 9) ension relieving techniques and local skin flaps. In: BSAVA
Manual of Canine and Feline Wound Management, ed. D Fowler and JM
Williams, pp. 57–68. BSAVA Publications, Gloucester
Postoperative care Gamblin RM, Sagartz JE and Couto CG (1997) Overexpression of P53 tumor
suppressor protein in spontaneously arising neoplasms of dogs. American
Journal of Veterinary Research 58, 857–863
Pain control Gardner DG (1995) Canine acanthomatous epulis. The only common
spontaneous ameloblastoma in animals. Oral Surgery, Oral Medicine, Oral
Regional nerve blocks (infraorbital, inferior alveolar and Pathology, Oral Radiology and Endodontics 79, 612–615
middle mental) and local infiltration are performed intra- Hammer A, Getzy D, Ogilvie G et al. (2001) Salivary gland neoplasia in the dog
and cat: survival times and prognostic factors. Journal of the American Animal
operatively with longer-lasting local anaesthetics, such as Hospital Association 37, 478–482
0.5% bupivacaine. Harvey CH and Emily PP (1993) Small Animal Dentistry. Mosby Year Book, St Louis

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