Disorders Of The Retina, Vitreous And CHoroid Flashcards
What are the 3 posterior chambers/
Vitrueous -> retina -> choroid
What arteries supply in the inner and outer layers of the rretina?
Central retinal artery = inner layers
Ciliary arteries - supply the outer layre
What is the copositio of vitrueou?
99% water
1% ssolid portion
Whaat cells span all the 10 layers of the retina but does not contribute to neural transduction?
Muller’s cells
What is the layer of the neuron relaysystem of the light signal transduction?
IBOP
Inner = Bipolar
Outer = Photoreceptor
What is the vascular layer that comes from the long and short posterior ancillary arteries???
Choroid
What proceure is used to enable physicians to monocularly view the central 15deg of the retinA?
Direct ophthalmoscopy
What procedure is done in combination with a condensing lens wither 78 diopter or a 90D condensing lens?
Slit-lamp biomicroscopy
What procedure is done to give the widest stereoscopic view of the retina?
Indirect ophthamloscopy
What proceudre is done to take pictures of the eye by IV inkection of sodium fluorescein dye?
Fundus photo and retinal angiogram
What layers of the retina are HYPERREFLECTIVE?
Plexiform and Fibrous layers
What are the risk factors of diabetic retinopathy?
Duration of DM
Age of dix: younger age
Glycemic control
BP control
Serum lipids: INC
Nephropathy
Anemia: LOW HCT
Pregnancy: high levels of estogen
What is the first clinical sign of Diabetic Retinopathy?
Microaneurysm
What happens if there is ischemic hypoxia?
Upregulation pro-inflammatory factors such as VEGF
What are the 2 classifications of Diabetic retinopathy?
Non-proligerative diabetic retinopathy
Proliferative diabetic retinopathy
What clasification of diabetic retinopathy is characterized by capillary damage & breakdown of the retinal blood barrier?
Non-proliferative diabetic retinopathy
What is the cause of NPDR?
Microvascularization changes
What aer hte typical fundus findings in NPDR?
Microaneurysm
Dot and blot retinal hemorrhages
Circinate exudates
Macular edema
Macular ischemia
What is affected in severe NPDR?
All quadrants of the retina
what is seen in severe nPDR?
Hyperfluorescent dots : microaneurysms
Dye leakage
What classification of diabetic retinopathy has sustained capillary damage and progresses into angiogenesis caused by extensive ischemia?
Proliferative diabetic retinopathy
What is the hallmark of PDR?
Growht of abnormal new vessels either on the disc or on the retina
What are the diff tx options for diabetic retinopathy?
Laster photocoagulation
Panretinal photocoagulation
Focal and grid laser treatment
Retinal photocoagulation
Intravitreal anti-VEGF
Retinal surgery for vitreous hemorrhage
What DR tx is used to decrease the O2 demande by use of laser tx?
Laser photocoagulation
What DR tx is used when the disease reahes the proliferative high risk stage?
Panretinal photocoagulation
What DR tx is used to treat px with macular edema?
Focal and grid laser tx
Wjat is the diff betw FOcal and Grid laser tx?
Focal treatment = macular edema due to focal leakage
Grid treatment = macular edema due to diffuse leakage
What is the best form of management for edema secondaty to diabetic retinopathy?
Itnravitreal injection for anti-VEGF
What re the retinal manifesations of hypertension?
Vasoconstriction = focal/diffuse
Leakage = retinal hemorrhages, hard exudates, soft exudates, optic nerve edema
Arteriosclerosis = AV ratio 1:2 or 1:3 (normally retina AV ratio is 2:3)
What is the KWB classification of hypertensive retinpathy?
Grade 1: slight sclerosis
Grade 2: definite sclerosis & AV nicking
Grade 3: leakages, hemorrhages
Grade 4: uncontrollable high leaking, papilledema is evident
What causes retinal vein occlusion?
Thrombosis
What are the characteristics of retinal vein occlusion?
Branch retinal vein occlusion
Central retinal vein occlusion
What causes branch retinal vein occlusion?
AV crossing defect
Angiogram = blocked fluorescence from this hemorrhage
What happens in central retinal vein occlusion?
Hemorrhages in 4 quadrants of the retina
What is the tx used for retinal vein occlusion?
Anti-VEGF
- earlier admin
- to improve vision
- 3 monthly dosing
Lessen effects of ischemia (like neovascularizaation)
What causes retinal artery occlusion?
Embolic phenomenon from calcificd internal carotid artery
What are the 2 characteristics of retinal artery occlusion?
Branch retinal vein occlusion
Central retinal vein occlusion
What is the appearace of branch retinal vein occlusion?
Retina lwhitening in the area of the occluded artery
Sudden painless loss of vision
Pallor of the superior retina
What are the characteristics of cental retinal vein occlusion?
Fundus with a cherry red spot
-> increased pigmentation fo the fovea (excessive pallor of surrounding edematou retina)
What is the 90 mins golden period of central retina vein occlusion?
This is 1 of 2 absolute ophthalmic emergencies bcos it can cause signfiicant and irreversible damge if not treated within 90mins
What is the tx for retinal artery occlusion?
Reperfusion below 90 mins = if severe and permanent visual loss is ecptected
Dislodged emboli
What are the features of retinal detachment?
RPE pump dysfunction
Subretinal fluid
Floaters
Flashes of light
Scotoma beginning from the periphery vision proceeding/encroaching centrally
What is a type of retinal detachment with retinal break/tear?
Rhegmatogenou retinal detachment
What ar theclinical features of rhegmatogenou retinal detachment?
Suddent onset of blurry vision, wavy vision, visual field cuts, flashes and floaters
What type of retinal detachment does not have retinal break or tear and causes blurry vision of variable onset?
Non-rhegmatogenous retinal deatchment
What are the 2 types of NRRD?
Exudative = iNC exudation beneath the retina -> accumulation of fluid
Tractional
What are the causes of exudative and tractional NRRD?
Exudative = inflammation, tumors, accelerated or malignant hypertension
Tractional = diabetes, trauma and ischemic retinopathies
What are the tx for retinal detachment?
Pars plana vitrectomy
Tx of the underlying cause
What is the main mode of management for exudative NRRD?
Treatment of undelrying medical cause
What is the indication of Pars plana vitrectomy?
If retinal detachment is secondary to a retinal break or tractional RD
