Diagnostic Ophthalmology

A 7-year-old spayed female shih tzu was examined by the ophthalmology service at the Western College of Veterinary Medicine. This dog was presented for a chronic history of red eyes and mild bilateral periocular discharge. The menace responses, and palpebral, oculocephalic, direct and consensual pupillary light reflexes were normal bilaterally. Schirmer tear test (Schirmer Tear Test Strips; Alcon Canada, Mississauga, Ontario) values were 18 and 17 mm/min in the right and left eyes, respectively. The intraocular pressures were estimated with a rebound tonometer (Tonovet; Tiolat, Helsinki, Finland) and were 18 mmHg bilaterally. Fluorescein staining (Fluorets; Bausch & Lomb Canada, Markham, Ontario) of the corneas was negative bilaterally. On direct examination of both eyes there was mild mucoid periocular discharge. Following application of 0.5% tropicamide (Mydriacyl; Alcon Canada, Mississauga, Ontario), examination of both eyes using a transilluminator (Welch Allyn Finoff Transilluminator; Welch Allyn, Mississauga, Ontario) and handheld biomicroscope (Kowa SL-15 Portable Slit Lamp; Kowa, Tokyo, Japan) revealed multifocal white to yellow, subconjunctival masses affecting the palpebral conjunctiva of the upper and lower eyelids, mild conjunctival hyperemia, scattered superficial corneal vascularization and scarring, and a lackluster cornea. Indirect ophthalmoscopic (Heine Omega 200; Heine Instruments Canada, Kitchener, Ontario) examination was completed and did not reveal abnormalities in either eye. Photographs of the right eye at presentation are provided for your assessment and are also representative of the left eye (Figure 1)