Ocular manifestations of systemic disease: DM Flashcards
Ocular manifestations of diabetes
- Refractive Changes
- Fluctuation in blood sugar
- Stabilizing of blood sugar will help stop refractive changes - Extraocular muscles
- DM affects 3rd/6th - Pupil and iris abnormality
- Respond sluggishly to light or fail to dilate with mydriatic eyedrops
- Rubeosis Iridis (neovascularization) - Cataract
- Ischemic optic neuropathy
Risk factors of diabetic retinopathy
Duration of DM
Level of glycemic control
HTN/ HLD/ Obesity
Renal Disease/ Anemia
Pregnancy
Smoking
Classifications of DM retinopathy
- Non-proliferative DM retinopathy
- Proliferative DM retinopathy
- Maculopathy
Non-proliferative DM retinopathy
Absence of abnormal blood vessels
- Mild
- Moderate
- Severe
What can be observed in mild non-proliferative DM retinopathy?
Microaneurysms: Weakened arterioles/capillaries earliest sign
What can be observed in moderate non-proliferative DM retinopathy?
- Dot and blot hemorrhages
- Flame-shaped hemorrhages
- Cotton wool spots (Damage to nerve fibres)
- Hard Exudates (Sharply defined, bright yellow) 2° to leakage of lipids and proteins from microaneurysm
- Retinal Edema
When should microaneurysm be treated?
Microaneurysm near macular require treatment; but exudation with edema away from macular do not need to be treated
What can be observed in severe non-proliferative DM retinopathy?
4 or 2 or 1 rule
- Dark blot hemorrhages in 4 quadrants
- Venous beading/looping/segmentation in ≥2 quadrants
- Intra-retinal microvascular abnormalities (IRMA) in ≥1 quadrant
Cotton wool spots
Anyone with severe NPDR requires treatment
*Cotton wool spots and venous beading are signs of ischemia
Proliferative DM retinopathy
Neovascularization (New vessel formation) occurs as a response to retinal ischemia
Location of new vessels in proliferative DM retinopathy
New vessel disc
New vessel elsewhere
Visual loss in proliferative DM retinopathy can be due to
Vitreous haemorrhage
Tractional retina detachment
Maculopathy in DM retinopathy
Hard exudates and edema in macular and retina thickening
- can lead to visual loss
- diagnosed by Optical Coherence Tomography (OCT) (presence of edema)
What is macular edema?
- Abnormal leakage and accumulation of fluid in the macular from damaged blood vessels
- Swelling and subsequently thickening of the macular can cause vision to distort
Causes of macular edema
- Diabetic Macular Edema
- Microaneurysm causing leakage of lipids
- Can lead to loss of vision - Post eye surgery
- Age related macular degeneration
- Deterioration and breakdown of macula
- Neovascular AMD or “wet” AMD allows for blood vessel which can grow in the choroid which can leak - Inflammatory disease affecting the eye
- Uveitis - Blockage of retinal blood vessels
- E.g. Retinal vein occlusion 2’ atherosclerosis
- Leakage into retina, regulating in macular edema
Symptoms of macular edema
Asymptomatic
Blurry/ wavy vision near or in centre of vision field
Colour desaturation
Can lead to central vision loss
Investigations for macular edema
- VA
- Optical Coherence Tomography
- Fluorescein angiogram (Inject dye into blood vessels of retina to look for any damage)
- Amsler Grid: Metamorphopsia
Management for macular edema
- Focal: Macular Focal Laser Photocoagulation
- Diffused: Anti-VEGF Injection/Intra-vitreal injections of corticosteroids
- Corticosteroid/NSAIDs (Reduces inflammation)
- Vitrectomy removes vitreous gel to reduce pulling on the macula
Complications of diabetic retinopathy
Neovascular glaucoma
Vitreous haemorrhage
Tractional retinal detachment
DM macular edema
-> leads to blindness
Management of DM retinopathy
- Screening: Regular DM retinal photography
- Tight glycemic control (HbA1c ≤ 7%,)
- Control comorbidities/cardiovascular risk factors (HTN, HLD, renal disease)
- Pan-retinal photocoagulation (PRP) for PDR/ Severe NPDR
- Focal: Macular Focal Laser Photocoagulation (for DME)
- Diffused: Anti-VEGF Injection/Intra-vitreal injections of corticosteroids (for PDR or DME)
- Vitrectomy
When stating diagnosis for DRP there are 2 parts of reporting the diagnosis
- state presence/absence of diabetic macular disease
- degree + type of diabetic retinopathy
Complications of Intra-vitreal injections of corticosteroids
- Transient increase in IOP
-Injection related infectious endophthalmitis - Sterile intraocular inflammation (SII)
- Brolucizumab-associated retinal vasculitis (BARV)
Classifications of maculopathy
Centre-involving (CSME) vs Non centre-involving
Criteria of clinically significant macular edema
- Retinal thickening within 500 microns of macular centre
- Hard exudates within 500 microns of macular centre with adjacent retinal thickening
- ≥1 disc diameters of retinal thickening, part of which is within 1 disc diameter of macular centre
Any 1 of the above present = CSME
