Diabetic Retinopathy [aao course] Flashcards
Diabetes Control and Complications Trial (DCCT)
patients treated with intensive glucose control reduced their risk of developing retinopathy by 76% and slowed progression of retinopathy by 54%
Which eye condition is an independent risk factor for poor survival?
Proliferative diabetic retinopathy (PDR). PDR is found in 67% of patients with 35 or more years of diabetes mellitus.
Nonproliferative Diabetic Retinopathy - 3 types
Mild, moderate, severe NPDR
The most common cause of visual loss among patients with DR is ________
diabetic macular edema (DME)
Mild NPDR is characterized by __________
the presence of relatively few microaneurysms. There are no changes as noted for moderate or worse NPDR.
Moderate NPDR is characterized by _________
cotton-wool spots, intraretinal hemorrhages and/or microaneurysms, venous beading, and intraretinal microvascular abnormalities (IRMA). None of the findings meet the criteria for more severe retinopathy.
Severe NPDR is characterized by _____
cotton-wool spots, venous beading, and any 1 of the following recalled by the “4-2-1 rule”:
Intraretinal hemorrhages in 4 quadrants
Venous beading in 2 quadrants
Severe IRMA in 1 quadrant
PDR findings may include _______
neovascularization of the disc (Figure 5), neovascularization elsewhere (NVE), vitreous and/or preretinal hemorrhage, traction or traction-rhegmatogenous retinal detachment, and neovascularization of the iris (NVI) and/or neovascularization of the angle (NVA).
Diabetic Macular Edema
Breakdown of the blood-retinal barrier and leakage from retinal capillaries is a hallmark of DR and a common cause of vision loss.
Clinically Significant Macular Edema
The ETDRS established that all DME did not warrant treatment and coined the term clinically significant macular edema (CSME). It is characterized by the presence of at least 1 of the following:
- Thickening of the retina at or within 500 microns of the center of the macula
- Hard exudates at or within 500 microns of the center of the macula associated with thickening of adjacent retina, not residual hard exudates remaining after disappearance of retinal thickening
- Retinal thickening 1 disc area or larger, any part of which is within 1 disc diameter of the center of the macula
Cystoid macular edema is characterized by ________
the presence of round or oval cystoid areas of low reflectivity
DME with serous retinal detachment is characterized by ________
the presence of a dome shaped elevation in the subretinal space with an overlying hyper-reflective and thickened outer retina
DME with vitreomacular traction is characterized by ______
the presence of epiretinal membrane (ERM) and abnormal vitreoretinal adhesions that result in tractional thickening of the macula
Advanced vision loss secondary to diabetic retinopathy can occur secondary to
- CSME
- Macular ischemia
- Vitreous hemorrhage
- Tractional retinal detachment
Diagnosis
- macular edema (retinal thickening in the macular area)
- optic nerve head neovascularization and/or neovascularization elsewhere
- signs of severe NPDR (e.g., extensive retinal hemorrhages/microaneurysms, venous beading, and intraretinal microvascular abnormalities).
These features can often lead to visual impairment.
Based on the results of the Diabetic Retinopathy Study (DRS) and ETDRS Research Group, laser photocoagulation is advised for patients with ______
HRPDR &/or CSME. In both instances, individuals who are treated appropriately have better visual outcomes than those who are not treated. Iris and angle neovascularization are also indications for laser photocoagulation.
Color fundus photography can detect…
disease that may be overlooked clinically.
Fluorescein Angiography should be obtained…
before treating CSME to identify treatable lesions.
Wide-field angiograms on average demonstrate…
3.2 times more retinal surface area then the standard 7 fields. This allows for better identification of nonperfusion and neovascularization.
Ultrasonography is a useful test in eyes with…
vitreous hemorrhage and other such forms of media opacity to determine the presence or absence of retinal detachment.
OCT is very sensitive at detecting…
macular edema, quantifying the edema, and providing a way of monitoring the edema after treatment
High-Risk Proliferative Diabetic Retinopathy: according to the Diabetic Retinopathy Study (DRS), there was a 50% reduction in severe vision loss at 5 years in HRPDR patients who received…
PRP treatment versus untreated control eyes.
The ETDRS trial demonstrated that eyes with CSME benefited from…
focal argon laser photocoagulation treatment. Treatment under guidance of fluorescein angiogram is recommended.
____________ agents are the most commonly used in the management of DME.
Antivascular endothelial growth factor
______ not only relieves any tractional forces, but also may improve oxygenation of the retina in patients presenting DME with Vitreomacular Traction.
Vitrectomy
The Diabetic Vitrectomy Study (DRVS) found that _______ benefited type 1 diabetics with severe nonclearing vitreous hemorrhage.
early vitrectomy
Vitrectomy is recommended in cases of progressive Tractional Retinal Detachment that…
involve or threaten the macula as well as cases of combined tractional and rhegmatogenous detachments.
Complications of laser treatment include…
iris stromal burns, accommodative insufficiency and asthenopia, elevated intraocular pressure, exudative retinal detachment, hemorrhage, choroidal neovascularization, subretinal fibrosis, optic neuropathy, visual field loss, and inadvertent foveolar burns.
