Lecture 4 - Diabetic Retinopathy Flashcards
If your patient’s A1c was 6, what was their average blood sugar over the last 3 months?
130 - you can add or subtract 30 from here (Ex: 160 is A1c 7 or 100 is 5)
which ethnicity has the highest prevalence of DM?
american indians/alaska natives > non-hispanic blacks > hispanics > asian americans > whites
for a patient with DM, what is their A1c, fasting plasma glucose and oral glucose tolerance test?
A1c = 6.5 or above, fasting plasma glucose = 126 or above and oral glucose tolerance test = 200 or above (pre-diabetes = 5.7-6.4, 100-125, 140-199 and normal = 5, 99 or below, 139 or below)
what did the diabetes control and complications trial (DCCT) conclude?
demonstrated benefits of intensive blood glucose control in patients with T1DM in regards to development and progression of diabetic retinopathy
what did the united kingdom prospective diabetes study (SUKPDS) conclude?
showed a 21% reduction in the risk for progression of diabetic retinopathy over a 12 year period for the intensive glycemic control group
what did the wisconsin epidemiologic study of diabetic retinopathy (WESDR) conclude?
severity of diabetic retinopathy is related to duration of disease (after 20 years 99% T1DM and 60% T2DM had retinopathy)
what did the early treatment diabetic retinopathy study (ETDRS) study conclude?
gave standards for grading amount or diabetic retinopathy, clinically significant macular edema, demonstrated benefit of focal or grid laser, early scattered PRP not indicated in mild/moderate DR resulted in small reduction for risk of severe vision loss and ASA therapy had no impact on DR progression, risk of vitreous hemorrhage, VA loss but did reduce risk of comorbidity and mortality
what are some diabetic complications systemically?
periodontal (gum) disease, neuropathy (hands/feet, digestion, carpal tunnel, ED), foot ulcers, non-traumatic lower limb amputations, kidney failure/dialysis, heart disease/stroke, 7th cause of death
what can prevent diabetic complications?
A1c point drop, BP control, control LDL, foot care programs, detecting/treating early kidney disease
what are some ocular complications of diabetes?
refractive changes (increased glucose levels in lens), dry eyes (decreased corneal sensation), snowflake cataract (sorbitol), PSC, glaucoma (neo or normotensive), CN6 palsy, CN3 palsy, CN4 palsy, diabetic papillopathy (optic neuropathy)
what causes a CN6 palsy in diabetes?
poor blood flow or ischemia, sudden onset, transient and resolves in 3-6 months
what causes diabetic papillopathy (optic neuropathy)?
increased leakage or microaneurysms, minimal affect on VA, unilateral or bilateral, resolved in 2-10 months (different than NAION which can be caused by DM or HTN)
what is metabolic syndrome?
any 3 of the following = central obesity (40 men/35”women), triglycerides > 150, HDL cholesterol 130/85, fasting BS > 100, being treated for dyslipidemia/HTN/DM
what is classified as mild NPDR?
microaneurysms, dot/blot mild-moderate in less than 4 quadrants, hard exudates (lipoproteins), risk of DME
what is the follow up recommended for mild NPDR?
9 months to 1 year (ODs can manage)
what is classified as moderate NPDR?
microaneurysms/hemorrhages mild to moderate in more than 4 quadrants, hard exudates, CWS (cystoid bodies), venous beading in less than 2 quadrants, IRMA, risk of DME 30-35%
what is the follow up recommended for moderate NPDR?
6 months
what is classified as severe NPDR?
4-2-1 rule (at least one needed) = microaneurysms/hemorrhages in all 4 quadrants, venous beading in 2 or more quadrants, moderately severe IRMA in one quadrant
50% develop PDR in 15 months
what is classified as very severe NPDR?
same as severe but 2 or more of the categories
50% develop PDR in 15 months
what is the follow up recommended for severe/very severe NPDR?
3 months or a retinal consult may be needed
what is the treatment for severe/very severe NPDR?
PRP may be beneficial (ETDRS) but most surgeons hold off until PDR develops because it can cause VA loss
what is the baseline photograph testing for diabetic retinopathy?
seven standard diabetic photograph fields - then put together in a mosaic (can be done 2 times per year)