Non proliferative diabetic retinopathy by phaneendra akana
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Transcript of Non proliferative diabetic retinopathy by phaneendra akana
NON-PROLIFERATIVE DIABETIC RETINOPATHY
MOHAN PHANEENDRA AKANAFinal M.B.B.S Part-1
7th SEMESTERNOV 11,2015
What is the Retina?• The retina is a multilayered, light sensitive neural
tissue lining the inner eye ball. Light is focused onto the retina and then transmitted to the brain through the optic nerve.
• The macula is a highly sensitive area in the center of the retina, responsible for central vision. The macula is needed for reading, recognizing faces and executing other activities that require fine, sharp vision.
Retina
RETINA
Diabetic Retinopathy (DR)Definition
• Progressive dysfunction of the retinal blood vessels caused by chronic hyperglycemia.
• DR can be a complication of diabetes type 1 or diabetes type 2.
• Initially, DR is asymptomatic, if not treated though it can cause low vision and blindness.
Healthy Retina
Diabetic Retinopathy
Diabetic retinopathy symptomsDiabetic retinopathy is asymptomatic in early stages of the diseaseAs the disease progresses symptoms may include• Blurred vision• Floaters• Fluctuating vision• Distorted vision • Dark areas in the vision• Poor night vision• Impaired color vision• Partial or total loss of vision
Risk factors
• Duration of diabetes • Poor Blood Sugar control• HTN• Hyperlipidemia
How diabetes cause vision loss Mechanism of VISION LOSS
Preclinical changes
Macular edema
Proliferative DR
Diabetes Background
DR
Clinical significant
macular edema
Vitreous hemorrhage
and/or Retinal detachment and/or
neovascular glaucoma
Preproliferative DR
Vision loss
Pathophysiology
Diabetic Retinopathy is a microvasculopathy that causes:• Retinal capillary (microvascular) occlusion • Retinal capillary (microvascular) leakage
Microvascular OcclusionMicrovascular occlusion is caused by:• Thickening of capillary basement membranes• Abnormal proliferation of capillary endothelium• Abnormalities in platelet function (Increased
adhesion)• Increased blood viscosity• Defective fibrinolysis
Cotton – wool spots
Neovascularization
Ischemia
Neovascular glaucoma
Microvascular Occlusion
Fibrovascular bandsVitreous hemorrhage
Increased VEFG
Tractional retinal detachment
Infarction
Microvascular leakageMicrovascular leakage is caused by:• Impairment of endothelial tight junctions• Loss of pericytes• Weakening of capillary walls• Elevated levels of vascular endothelial growth
factor (VEGF)
Edema Retinal hemorrhageHard exudates
Microvascular Leakage
Ophthalmic features of non-proliferative diabetic
retinopathy• Microaneurysms(inner nuclear)• Retinal hemorrhages(dot and blot)• Oedema(macular)• Hard (retnal lipid)exudates• Cotton-wool spots(nerve fiber layer)• Venous abnormalities• Intraretinal microvacular abnormalities• Dark-blot hemorrhages
HyperglycemiaDamage to retinal capillaries
Weakens capillary walls
Small outpouchings leaky,fluid seep into retinaof vessel lumen
fluid deposition under macula
rupture Macular edema
hemorrhage Resolution of fluid lakes
Sediments of lipid byproducts
Glucose galactose Sorbitol galacitol
Can’t diffuse out of the cells(lens epithelial,pericytes,schwann cells)
Incr. intracellular conc.Inc. osmotic forcesWater diffuse into cellElectrolyte imbalanceDamage to pericytes on vessel wallloss of contraction & relaxation of
vessel wallCotton wool spots
Associate features:
• Vitreous hemorrhage• Retinal detachment• Neovascular glaucoma• Premature cataract• Cranial nerve palsies
ETDRS study classification:• Mild NPDR• Moderate NPDR• Severe NPDR• Very severe NPDR
Findings Obsd
International Clinical Diabetic Retinopathy Disease Severity Scale
Proposed Disease Severity Level Findings Observable upon Dilated Ophthalmoscopy
No apparent retinopathy No abnormalities
Mild nonproliferative diabetic retinopathy Microaneurysms only
Moderate nonproliferative diabetic retinopathy More than just microaneurysms but less than severe NPDR
Severe nonproliferative diabetic retinopathyAny of the following: More than 20 intraretinal hemorrhages in each of four quadrants Definite venous beading in two or more quadrants Prominent IRMA in one or more quadrants and no signs of proliferative retinopathy.
Proliferative diabetic retinopathy One or both of the following: Neovascularization Vitreous/preretinal hemorrhage
Mild NPDR• Atleast one microaneurysm(Ma)
MILD NONPROLIFERATIVE DIABETIC RETINOPATHY
Microaneurysms
Moderate NPDR• Microaneurysms or intraretinal hemorrhages(Ma/H)
in 2 or 3 quadrants• Soft exudates• Venous beading(VB)• Intraretinal micro vascular abnormalities(IRMA)
defenitely present
Moderate Nonproliferative Diabetic Retinopathy (NPDR)
Hard exudates
Flamed shaped hemorrhages
Microaneurysm
Moderate Nonproliferative Diabetic Retinopathy (NPDR)
Hard exudates
microaneurysm
Severe NPDR• H/Ma(>20) in all 4 quadrants• VB in ≥2 quadrants• IRMA in ≥1 quadrant • No signs of proliferative retinopathy• “4-2-1 rule.”
Severe Nonproliferative Diabetic Retinopathy (NPDR)
Venous beading
Very severe NPDR• Any 2 of the severe NPDR (4 – 2 - 1)
Primary prevention Strict glycemic control Blood pressure control
Secondary prevention Annual eye exams
Tertiary prevention Retinal Laser photocoagulation Vitrectomy
Diabetic Eye DiseaseKey Points
• Treatments exist but work best before vision is lost
RECOMMENDED EYE EXAMINATION SCHEDULEDiabetes Type Recommended
Time of First Examination
Recommended Follow-up*
Type 1 3-5 years after diagnosis
Yearly
Type 2 At time of diagnosis
Yearly
Prior to pregnancy (type 1 or type 2)
Prior to conception and early in the first trimester
No retinopathy to mild moderate NPDR every 3-12 monthsSevere NPDR or worse every 1-3 months.*Abnormal findings may dictate more frequent follow-up examinations
Treatment of NPDR
• No ocular intervention is warrented,until disease reaches the proliferative stage.
• As proliferative stage arouses,the treatment is carried out through various measures like….
1. Pan retinal Laser photocoagulation2. Intra-vitreal anti VEGF injections3. Anti-platelet theraphy4. Anti hypertensive agents5. Anti-angiogenesis agents
DIABETIC RETINOPATHY TREATMENTOnce DR threatens vision treatments can include:
Laser therapy to seal leaking blood vessels (focal laser)
Laser therapy to reduce retinal oxygen demand (scatter laser)
Surgical removal of blood from the eye (vitrectomy)
Pan retinal Laser Photocoagulation
Laser Photocoagulation is recommended for eyes with:• Clinical significant macular edema CSME • High risk Proliferative diabetic retinopathy• Lasers named for active medium• Choice of optimal wavelength depends on
absorption spectrum of target tissues• Used for retinal & choroidal abnormalities• Recent appplications have exploited the
subthreshold effects of laser.
DIABETIC RETINOPATHY TREATMENTNEWER DEVELOPMENTS:
The use of anti-vascular endothelial growth factor antibodies has been shown to be useful in the treatment of DR
Anti-VEGF antibody treatment appears to be useful for both macular edema and proliferative retinopathy
Studies to determine the exact role of anti-VEGF treatment in relation to laser treatment in specific situations are underway.
CONCLUSIONS
Diabetic Retinopathy is preventable through strict glycemic control and annual dilated eye exams by an ophthalmologist.
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