Lecture XI Flashcards
Pupil sparing CN III defect is more concerning for what type of problem? Why?
Systemic disease, since the nerve carries the parasympathetic fibers in the outer ring of the nerve.
Bilateral disc edema, with good vision, and no RAPD = ?
Papilledema
DM is the leading cause of blindness, specifically in what age group?
20-74
What are the three major ophthalmologic changes that occur with DM?
- Refractive error changes
- Cataracts
- Retinopathy
What are the small organs that are affected with small vessel dz 2/2 DM? (3)
- Eyes
- Kidneys
- Peripheral nerves
What is the chemical mediator of increased capillary permeability/abnormal vasoproliferative due to increase BG?
VEGF
What are the two forms of diabetic retinopathy?
Proliferative retinopathy
Non-proliferative form
What is the non-proliferative form of DM retinopathy?
Retinal blood vessels are leaky, which causes leakage into the macula which reduces vision
What is the progression of problems that occurs with non-proliferative DM? (4)
- Microaneurysm
- Leakage of intravascular fluid (hard exudates)
- Intraretinal hemorrhages
- Retinal ischemia (cotton wool spots)
What is the treatment for nonproliferative DM retinopathy?
No immediate treatment
What determines a high risk of imminent PDR?
- Cotton wool spots
- Capillary dropout
- Venous bleeding
What causes the neovascularization with proliferative form of DM retinopathy?
Tissue hypoxia causes proliferation
True or false: pts with proliferative retinopathy can also have all the s/sx of NPDR
True
What are the fundoscopic findings of PDR?
- Neovascularization
- Vitreous hemorrhages
- Fibrous proliferation
What eventually happens to the new blood vessels with PDR?
Vitreous hemorrhage
What are the s/sx of vitreous hemorrhage?
- Floaters/cobwebs
- Sudden loss of vision
What should be done with vitreous hemorrhages?
Refer to ophthalmologist
What happens with scar formation in the eye?
Scar will cause traction on the retina–may lead to retinal detachment
How do people lose vision with diabetic retinopathy?
Several causes-but macular edema or vitreous hemorrhage and traction RD
What are the two basic causes of vision loss with NPDR? Which is treatable?
- Ischemic maculopathy
- Macular edema (generally treatable)
What are the goals of photocoagulation with PDR?
- Involute neovascular tissue
- Prevents further neovascularization
- Reduces risk of vitreous hemorrhage, and reduce traction retinal detachment
What is the general idea with photocoagulation with PDR?
Kill off peripheral vision (Retina) to maintain central vision (blood flow to the macula)
When is vitrectomy indicated?
If vitreous hemorrhage or retinal detachment
What is a vitrectomy?
Suction out the hemorrhages
True or false: proteinuria is a risk factor for macular edema
True
What is the role of diuresis and BP control with macular edema in DM?
Improves–ACEI/ARBs particularly
True or false: PDR is a risk factor for MI, stroke, amputation, and death
True
What happens to the risk of nephropathy with the advent of PDR?
Increases the risk
What is the problem with dyslipidemia in the development of DM retinopathy?
Increases the chances of hard exudate formations
What are the DM screening guidelines for DM pts?
-Annual ophthalmologic exams
What are the two forms of laser photocoagulation treatment options?
- Focal macular laser for macular edema
- Panretinal photocoagulation for PDR
What are the findings of HTN retinopathy?
- Arteriolar sclerotic changes
- HTN changes
What is the major challenge with identifying HTN retinopathy?
Appears very similar to natural age changes
What are the characteristics findings on fundoscopy with arteriolar sclerosis?
- Less transparent vessels
- Copper/silver wiring light reflex broadens d/t the thickening and fibrosis of the vascular wall
What causes A/V nicking?
At the arterioles and veins share a common adventitial sheath at crossing sites causing A/V nicking
What is the normal artery:vein ratio (size)?
2:3
What is the pathogenesis of HTN causing retinopathy?
moderate elevation causes constriction of arterioles
Severe acute BP rises over what mmHg causes fibrinoid necrosis of the vessels, and exudates?
More than 200 / 120
What is the ophthalmologic consequence of malignant HTN?
Optic nerve edema and fibrinoid necrosis
What are the three most sensitive ophthalmoscopic indications of HTN? (in order)
- attenuation of arterioles
- Focal narrowing
- A/V changes
True or false: it may be difficult to differentiate chronic HTN from normal involutional changes
True
What are venous beading seen in?
Advanced NPDR
What are copper wiring of vessels seen in? Why?
HTN retinopathy–increased arteriole pressure
What are the two major consequences of the neovascularization of PDR?
- vitreous hemorrhage
- Fibrous proliferation
What is the worst prognostic sign of hypertensive retinopathy?
Disc edema
