Eye 2 Flashcards
Diabetic retinopathy
-leading cause of new blindness among adults aged 20-65 years
-more common in poor controlled diabetes / cormorbities
-type 1 DM- 3 years after diagnosis
-type 2 DM- retinopathy is present in about 20% of patients at dx and may be presenting feature
-long standing poorly controlled diabetes
-damages the blood vessels
-grade of retinopathy (1-4)
-non-proliferative (1-3) vs. proliferative (4)
-young people get diabetes often now
-people see black spots
background retinopathy
-mild retinal abnormalities without visual loss
maculopathy
macular edema, exudates, or ischemia
-cranial 3, 4, or 6 palsy
diabetic retinopathy stats
-Present in ∼33% of all diagnosed diabetic patients.
-Present in ∼20% of type 2 diabetic patients at time of diagnosis of diabetes.
-By 20 years after diagnosis of diabetes, 99% of type 1 diabetic patients and 60% of type 2 diabetic patients will have diabetic retinopathy
nonproliferative diabetic retinopathy
-1-3 stages (mild, moderate, severe)
-mild, moderate, or severe
-Microvascular changes are limited to the retina
-dilation of veins
-microaneurysms
-cotton wool spots- white fully spots, due to ischemia
-retinal hemorrhages
-retinal edema- fluids
-hard exudates- proteins
-background retinopathy & maculopathy
nonproliferative diabetic retinopathy treatment
-control of blood glucose, BP
-photocoagulation- cauterize bleeding
-diabetic macular edema- VEGF-A - prevent new blood vessels from forming
-optimizing blood glucose, BP, kidney function, serum lipids
-glycemic control* most important modifiable factor in treating pts but intensive BP control also slows progression
-metformin reduces incident of retinal vein occlusion
proliferative diabetic retinopathy
-new blood vessels grow on the surface of the retina, optic nerve, or iris
-creates new vessels bc not enough oxygen due to high glucose
-neovascularization
-vitreous hemorrhage
-untreated-prognosis is extremely poor
-Arising from either the optic disk or the major vascular arcades
-Proliferation into the vitreous of blood vessels may lead to retinal detachment
-treatment-VGEF-A, photocoagulation, vascular endothelial growth factor (VEGF-A)
diabetic macular edema
central retinal swelling; can occur with any severity level of diabetic retinopathy; reduces visual acuity if center involved.
-inhibits human vascular endothelial growth factor A (VEGF-A)
hypertensive retinopathy
-chronic hypertension
-moderate vascular wall changes (“copper wiring”)
-more severe vascular wall hyperplasia (“silver wiring”)
-obliterative disease with total vascular occlusion
-retinal vascular damage caused by high BP
-most florid ocular changes occur in young pts with abrupt elevations of BP (may occur in pheochromocytoma, malignant hypertension, or preeclampsia-eclampsia)
-fundal abnormalities: hallmark of hypertensive crisis with retinopathy
-treatment is directed at controlling the hypertension
-EDEMA
-young people can get it too (pheochromocytoma) -> emergency situations not just chronic
-hypertension crisis- end organ damage (includes eyes)
hypertensive retinopathy funduscopic exam
-funduscopic examination shows
-arteriolar constriction
-arteriovenous nicking- veins over arteries -> narrows
-vascular wall changes
-flame shaped hemorrhages- larger than diabetic retinopathy
-cotton wool spots (retinal ischemia)
-yellow hard exudates (lipid deposition)
-papilledema- swelling at optic disc
-florid changes occur in pheochromocytoma, malignant hypertension, or preeclampsia-eclampsia
papilledema
-normal pressure glaucoma- normal pressure - narrowing of angle where fluid drains out of
-increased intracranial pressure
-tumor (space occupying lesion)
-infection
-hemorrhage (subdural, dural)
-LP exam -> rule out papilledema
-neuritis- multiple sclerosis
-vision impaired
-white large ring on image
central retinal artery occlusion
-Blockage of the central retinal artery
-Usually by embolism
-sudden
-pupil may respond poorly to direct light but constricts briskly when other eye is illuminated
-end artery occlusion- severe pain
-acute cases ->pale, opaque fundus with red fovea (cherry red spot)**
-an embolic obstruction sometimes visible
-if major branch occluded rather than entire artery -> fundus abnormalities and vision loss are limited to that sector of retina
-typically arteries are attenuated and may even appear bloodless
-blueish congested, blurry
-cause- embolism from atherosclerotic plaques, endocarditis, fat emboli, atrial myxoma, or thrombosis of a retinal artery; Temporal arteritis**
-ESR (temporal arteritis), diabetes, hyperlipidemia
central retinal artery occlusion treatment
-immediate treatment (decreasing intraocular pressure) indicated if occlusion occurred < 24 h earlier
-beyond 72 h- unlikely that increased perfusion will improve vision
-once retina has infarcted, blindness is permanent
-lay pt flat
-ocular massage- controversial
-high concentration of inhaled oxygen
-IV acetazolamide
-anterior chamber paracentesis
-early thrombolysis- if stroke
-RULE OUT STROKE - CAROTID ARTERY CLOT, temporal arteritis
central retinal vein occlusion
-blockages of central retinal vein by thrombus
-congested***
-painless visual loss can be sudden or gradual
-usually elderly pts
-predisposing factors- glaucoma, diabetes, hypertension, increased blood viscosity, and elevated Hct
-idiopathic
-uncommon in young people (antiphospholipid antibodies)
-neovascularization of retina or iris (rubeosis iridis) with secondary (neovascular) glaucoma can occur weeks to months after occlusion
-vitreous hemorrhage may develop in presence of retinal neovascularization
central retinal vein occlusion diagnosis
-by fundoscopy
-retinal veins appear distended and tortuous
-fundus congested and edematous
-widespread retinal hemorrhages appear
-retinal cotton wool spots
-optic disk swelling
-prognosis- if normal retinal perfusion is re-established, normal vision may return
-visual acuity at presentation is good indicator of final vision
-these changes are limited to 1 quadrant if obstruction involves only a branch of the central retinal vein
-time to vision improvement varies
-poor perfusion are more likely to develop complications and suffer severe vision loss
