Chronic Superficial Keratitis (Pannus) Pannus—superficial corneal vascularization/scar tissue Progressive, bilateral, can result in blindness • Cause – Thought to be immune-mediated (Infiltration of cornea with lymphocytes, plasma cells) – Increased ultraviolet light/high altitudes increases incidence • Signs – Opaque lesions that begin at limbus and extend into cornea • Milky, pink, or tan Chronic Superficial Keratitis (Pannus) Chronic Superficial Keratitis (Pannus) • Breeds – Ger. Shep, B. Collie, greyhound, Sib. Husky • Dx – r/o KCS, corneal ulcers • Rx – Corticosteroids often lifelong – Cyclosporine often lifelong – Antibiotic eye ointment • Client info – No cure – If Rx is stopped, disease will return and progress – High altitudes and ↑sun predispose animals DOGGLES!!!! Keratoconjunctivitis Sicca (KCS) Lack of tear production; tears lubricate, nourish, ↓bacteria, aid in healing Tears from 2 glands: 70%--Lacrimal gland; 30%--Nictitans gland • Signs – – – – – Recurrent conjunctivitis, corneal ulcers, keratitis Dull, dry, irregular cornea, conjunctiva Tenacious, mucoid ocular discharge Blepharospasm Crusty nares • Rx – Tear stimulation—cyclosporine, pilocarpine – Artificial tears • Client info – Px is guarded for resolution – Failure to treat → blindness KCS Cataracts Opacity of lens that causes reduced vision; most common disease of lens • Cause – Genetic – 2º to: • Diabetes mellitus (bilat; within 1 y of disease; ↑glucose → ↑fluid in lens) – Most common cause • • • • • • Trauma (unilateral; HBC, thorn penetration, shotgun pellet) Lens luxation Nutritional deficiency Uveitis Hypocalcemia Electrical shock • Rx – Surgical removal of lens – Treat underlying cause (e.g., Diabetes) • Client info – Most cataracts are inherited, so don’t breed affected dogs – Dogs can live quality lives even with bilat. cataracts Cataracts • Signs – Progressive loss of vision – Opaque pupillary opening • Dx – Must be distinguished from senile nuclear sclerosis • Normal old age change; graying of lens; bilat; usually does not affect sight CATARACTS Progressive Retinal Atrophy • A group of hereditary disorders causing loss of rods, cones, and/or blood supply – Breeds • Toy/min. Poodle, G. Ret, I. Set, C. Span, Schnauzer, Collie, Samoyed, N. Elkhound • Recessive gene isolated in some breeds • Signs—slow onset of blindness – Loss of night vision (rods) → loss of day vision (cones) → cataracts (±) • Dx – r/o metabolic disorders that could cause cataracts – Ophth exam • gray, granular appearance of retina • Hyperreflective retina • Vascular attenuation, optic nerve atrophy PROGRESSIVE RETINAL ATROPHY Normal canine retina PRA, optic nerve atropy and vessel attenuation Progressive Retinal Atrophy • Rx – None • Client info – This is an inherited disease – Avoid buying affected breeds • Have ophth exam by board certified ophth to r/o PRA – Blind animals adapt well • Have trouble in strange surroundings – Cats need well balanced diet • Taurine deficiency can lead to PRA Anterior Uveitis • Inflammation of uvea: ciliary body, iris, choroid • Causes – Inflammation/infection – FeLV/FIP, fungal, bacterial – Neoplasia – Trauma Uveitis – Clinical Signs • Blepharospasm • Aqueous flare – increased turbidity of aqueous humor • Miosis of affected eye • Iridal swelling or congestion • Keratic precipitates • Ciliary flush in limbal region • +/- Corneal edema • +/- hyphema Anterior Uveitis – hyphema Anterior Uveitis Anterior Uveitis – keratic precipitates Anterior Uveitis – Treatment • • • • • Topical steroids or Topical Anti-inflmmatory drugs (ocufen) Or systemic steroids Atropine – dilates eye, decreases pain Antibiotics – topically +/- systemically Anterior Uveitis – Client Info • • • • Recheck within 3 days Secondary glaucoma is frequent complication Prognosis depends on cause Treat for 2 months regardless of cause – blood-aqueous barrier disrupted for 6 weeks Proptosed Globe • Cause – Trauma – Conformation – Retrobulbar abscess or neoplasia • Clinical Signs – Protrusion of the globe, – Eyelids unable to close, may be trapped behind globe Prognosis • Favorable – brachycephalic dog, – positive direct or consensual pupillary light response – normal findings on posterior segment exam – proptosed eye with vision on initial presentation • Unfavorable indicators – – – – – – non-brachycephalic cat breed hyphema, no visible pupil facial fractures optic nerve damage and avulsion of 3 or more extraocular muscles Proptosed Globe Proptosed Globe – Treatment • Lubricate immediately • Reduce the globe into the socket ASAP to reduce trauma to optic nerve • Enucleation if optic nerve severed • Systemic and topical antibitics • +/- Steroids Proptosed Globe References http://www.vetmed.ucdavis.edu/courses/vet _eyes/ http://vanat.cvm.umn.edu/carnLabs/Lab24/L ab24.html Alleice Summers, Common Diseases of Companion Animals http://www.vetmed.wisc.edu/Data/CourseM aterial/Miller/Emergencies.pdf