Zygomatic Sialolithiasis Diagnosed with Computed Tomography in a Dog

Abstract

A 10-year-old castrated Shih-Tzu male dog was referred for examination of acute right exophthalmos, protrusion of the third eyelid and soft tissue swelling ventral to the globe. Ultrasonography revealed echogenic fluid around the right globe. Computed tomography (CT) showed an enlarged right zygomatic salivary gland compared with the left zygomatic gland and an amorphous cystic mass ventral to the right globe. Hyperdense material, which we suspected to be a sialolith, was identified in the right zygomatic gland. The zygomatic gland and the cystic lesion were removed, and a zygomatic sialocele with sialolith and ductal obstruction were found by histopathological examination. CT was a useful diagnostic tool for zygomatic sialolithiasis.

Sublingual sialocele in a cat

“…14,16 In our case, where the lesion was unambiguously lateralised on the right side, performing CT was not mandatory from a surgical perspective, but may have identified a possible cause, in particular sialoliths, even if these are rare. 8,13,16…”

“…MRI, which offers a superior soft tissue resolution, can also be used, but has other disadvantages, in particular a longer data acquisition time and lower precision for detection of soft tissue mineralisation. 14,16 In our case, where the lesion was unambiguously lateralised on the right side, performing CT was not mandatory from a surgical perspective, but may have identified a possible cause, in particular sialoliths, even if these are rare. 8,13,16 Many options have been described for surgical treatment of a sublingual sialocoele: draining of the mucocoele alone, removal of the entire gland complex (mandibular and sublingual glands), marsupialisation of the sublingual sialocoele or a combination of the last two techniques.…”

“…14,16 In our case, where the lesion was unambiguously lateralised on the right side, performing CT was not mandatory from a surgical perspective, but may have identified a possible cause, in particular sialoliths, even if these are rare. 8,13,16 Many options have been described for surgical treatment of a sublingual sialocoele: draining of the mucocoele alone, removal of the entire gland complex (mandibular and sublingual glands), marsupialisation of the sublingual sialocoele or a combination of the last two techniques. [1][2][3][4]7 In general, draining of the mucocoele or marsupialisation alone are not recommended owing to a high associated risk of infection and/or frequent recurrence.…”

“…4,11 CT is an interesting alternative method as all the salivary glands can be easily identified and the cause of the leak can sometimes be identified. 4,14,16 Moreover, it can clearly show the gland(s) and tissue(s) involved, giving added confidence to the surgical approach and management, whereas gross appearance can, on occasion, potentially be misleading. MRI, which offers a superior soft tissue resolution, can also be used, but has other disadvantages, in particular a longer data acquisition time and lower precision for detection of soft tissue mineralisation.…”

Exophthalmos associated to orbital zygomatic mucocele and complex maxillary malformation in a puppy

“…Despite the variable underlying causes, the clinical signs of these various conditions are very similar to one another. Diagnostic imaging can be useful to differentiate a zygomatic gland disease from other orbital diseases (Penninck et al, 2001;Bartoe et al, 2007;Boston, 2010;Lee et al, 2014). Cases of zygomatic mucocele were reported in a cat and in a ferret (Miller and Pickett, 1989;Speakman et al, 1997).…”