Ophthalmic problems in the geriatric patient (Proceedings)

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Ophthalmic problems in the geriatric patient (Proceedings)

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Nov 01, 2010
1234Next GERIATRIC CORNEAL DISEASES- CORNEAL CALCIUM DEGENERATION     ■ Calcium is deposited in the anterior to deep stroma of the cornea     ■ Secondary to systemic disease or age          • Hypercalcemia, Hyperphosphatemia, Hyperadrenocorticism, Uremia, Hypervitaminosis D     ■ Complications to Calcium Degeneration          • Pain when Calcium is exposed because of rough corneal surface          • Progressive vision impairment          • Sloughing of calcium           • Neovascularization into calcific areas     ■ Treatment for Calcium Degeneration          • Topical EDTA (1-5%)          • Trichlorcetic Acid          • Superficial Keratectomy - REFRACTORY CORNEAL ULCERS     ■ Also known as:          • Indolent ulcers, non-healing ulcers, Boxer ulcers, rodent ulcers, Recurrent corneal erosion syndrome, Spontaneous chronic corneal epithelial defects (SCCED)     ■ Clinical Signs          • Loosely adherent epithelium (lipping)          • Blepharospasms           • Neovascularization with chronicity     ■ Underlying Pathophysiology          • Absence of continuous basement membrane          • Decrease in hemidesmosomes          • Extracellular Matrix abnormalities     ■ Complications of Refractory Ulcers          • Chronic discomfort, Corneal infection, Corneal neovascularization, fibrosis, and vision loss     ■ Treatment for Refractory Ulcers          • Q-tip Debridement               » 15-25% success rate          • Linear Grid Keratotomy or Multiple Punctate Keratotomy               » 95% success rate          • Others (less than 50% success rate)               » Contact lens, Third eyelid flap, Chemical cauterization, Topical growth factors - CORNEAL ENDOTHELIAL DEGENERATION     ■ Spontaneous, progressive corneal edema     ■ Abnormal dystrophic endothelial cells     ■ Prevalent breeds          • Boston Terrier, Chihuahua, Dachshund, Poodle     ■ Pathology of Endothelial Degeneration          • 2500-2800 cell/mm2 in the dog          • Endothelial cells pump fluid from the cornea into the aqueous, keeping the cornea clear and dehydrated.          • As cells become dystrophic and die, the remaining cells enlarge to compensate.          • Once there are <500-800 cells/mm2 , compensation is lost and fluid is not adequately pumped out of cornea.     ■ Complications to Endothelial Degeneration          • Epithelial microbullae formation, Corneal ulcers, Keratoconus, Bullous keratopathy, Vision loss     ■ Treatment          • Hyperosmotic Agents (5% sodium chloride ointment)               » May decrease extent of epithelial bulla formation               » Does not allow for significant cornea clearing               » Decreases thickness of cornea          • Thermokeratoplasty if chronic erosions          • Penetrating Keratoplasty               » Improve vision               » Fresh donor cornea               » Complication- graft rejection, dehiscence, infection 1234Next