Canine zygomatic salivary mucocoele following suspected oropharyngeal penetrating stick injury

The images are courtesy of M Rhodes at Willows Veterinary Centre and Referral Service.

Salivary mucocoeles result from saliva leaking from the salivary glands, or ducts, into the surrounding tissues, thus causing inflammation and granulation tissue formation (Hedlund and Fossum 2007). The aetiology is unclear, but trauma, sialoliths, foreign bodies, neoplasia and duct obstruction have all been implicated (Spangler and Culbertson 1991, Bellenger and Simpson 1992, McGill and others 2009, Trumpatori and others 2007). Aspiration typically reveals tenacious, straw-coloured fluid (Slatter and Basher 2003). Staining with periodic acid Schiff allows the mucin content to be detected.

The canine zygomatic salivary gland is situated in the ventral orbit with one major and two to four minor ducts opening opposite the first maxillary molar (Evans 1993). Zygomatic mucocoeles have been described following non-specific trauma (Schmidt and Betts 1978, Pope and Bauer 1986), and as a postoperative complication following dental extraction (Adams and others 2011) and caudal hemimaxillectomy (Clarke and L'Eplattenier 2010). This short communication outlines the occurrence of a zygomatic mucocoele following suspected oropharyngeal stick injury.

A one-year nine-month-old neutered female collie-cross was referred for investigation of right-sided exophthalmos. The dog had yelped while running through bushes just prior to onset of right facial pain, swelling, exophthalmos, third eyelid protrusion and pain on opening its mouth.

Physical examination revealed …