Orbital Neoplasias - Dog and Cat

Primary orbital neoplasias are uncommon in dogs and cats.

Types Of Tumour

Meningioma is the most common primary tumour in dogs. It is a benign slow growing tumour that if untreated causes pressure atrophy.

Other tumours described include lymphosarcoma, adenocarcinoma, fibrosarcoma, multilobular ostersarcoma, glioma, myxoma, squamous cell carcinoma, rhabdomyosarcoma and canine lymphoid pseudotumour.

Clinical Signs

Unilateral, progessive and painless exopthalmos

Prominent and protruding third eyelid

Blindness, though not in all cases. This can help differentiate from glaucoma, which always causes blindness

Exposure keratitis, secondary to the exopthalmos

Retinal folds or retinal detachment on opthalmoscopic exam

Nasal discharge

Dilated/eccentric pupil

Treatment

Surgical exploration and removal of the globe and associated orbit contents is recommended.

Depending on the type of tumour chemotherapy or radiation therapy may be appropiate.

References

Maggs, D et al (2007) Slatter's Fundamentals Of Veterinary Ophthalmology (Fourth Edition) Saunders