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DIABETES AND
THE EYEDr. Namrata Gupta
Ocular complications in diabetes are frequent,
distressing and destined to become one of the
challenging problems of the future.
- Dr. Howard Root, 1935
Diabetes burden – Tip of the iceberg?
Undiagnosed Diabetes
Diabetic Population
Rate of Conversion of ‘PREDIABETES’ (Impaired Plasma Glucose) to DM is 10% annually
Objective• Diabetes is an emerging public health problem in Nepal• Despite a potential epidemic in Asia, there is lack of
awareness of this blinding disease (primarily retinopathy)
• Diabetes can effect virtually every structure of eye and not just blindness
• Early detection and timely management can prevent upto 90% of vision loss from PDR
Overview • Definition of diabetes• Diabetic effects on ocular structures• Diabetic retinopathy• Management and prevention
INTRODUCTION The term “diabetes mellitus” describes a metabolic disorder of
multiple etiology characterized by chronic hyperglycemia with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion , insulin action, or both
Effects of diabetes mellitus include long-term damage ,dysfunction and failure of various organs
Epidemiology Global prevalence of diabetes(WHO1): 171 million in 2000
366 million in 2030 !!! International diabetes federation2 – 386 million diabetics among which
80% live in developing countries
Diabetes is the major systemic disease that causes blindness in the United States and is the leading cause of blindness in working aged adults around the world(5th leading cause of all blindness)
Global prevalence of diabetic retinopathy: 34.6%
1. Global prevalence of diabetes: WHO: estimates of 2000 and projections of 20302. International diabetes federation: IDF diabetes atlas 2014 update
Around one million diabetics in Nepal (89% from urban parts)
The risk of blindness among diabetic persons is 25 times that of the general population
Prevalence of DR among diabetics is estimated to be 21.6 %
73% were aware of DR– 39% had prior retinal evaluation
Epidemiology
Diabetic retinopathy program: Tilganga institute of ophthalmology
Pathogenesis Disease of the capillaries and small vessels (microangiopathy) causes retinopathy, nephropathy, neuropathy , and heart diseases
Ocular effects of diabetesDiabetes can cause changes to virtually all structures of the eye• 1. Cornea + tears• 2. Aqueous• 3. Iris• 4. Lens• 5. Vitreous• 6. Retina• 7. Internal muscles• 8. External muscles• 9. Orbit
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8
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Orbit Diabetics are more prone to infection
• Orbital cellulitis (Bacterial origin)• Orbitorhinomucormycosis (dreaded form of orbital infection)
Lidsprone to infections due to high blood sugar level
Recurrent styes and blepharoconjunctivitis(Staph aureus, Staph Epidermidis)
Dangerous after surgery- endophthalmitis
Xanthelasma
• Ptosis- isolated third nerve palsy
• Diabetes is one of the most frequent etiologies of an acquired palsy where the onset of sudden diplopia is the main symptom
Extra-ocular muscles• Diabetes is one of the frequent etiology of acquired palsy
• The 3rd, 4th and 6th are affected (3rd and 6th are frequently cited)
6th Nerve Palsy• Most common• Horizontal diplopia in primarygaze and in gaze towards same side
3rd Nerve Palsy• Less common• Unable to elevate, depress or adduct,• Ptosis • Pupil sparing
• Short duration of hyperglycemia in diabetic, the paralysis disappears spontaneously with several weeks
• Long time of hyperglycemia in diabetic , it persists up to 6 months
DIABETIC NEUROPATHY
ConjunctivaDiabetes is a generalized microvascular disturbance, therefore, the abnormalities noted in the conjunctiva include:
• microaneurysms, • vasoconstriction, • vessel distension,• increased tortuosity
CORNEA
Corneal sensitivity is commonly impaired in diabetes- predispose to bacterial corneal ulcers, neurotropic ulcers and difficulties with contact lenses
Decreased reflex tear secretion- dry eye
Intrinsic abnormalities of the epithelial basement membrane complexes , with impaired barrier function lead to:
Superficial punctate keratitis Poor healing after trauma Prolonged recovery after intraocular surgery
Diabetic pupillary defect
Medical lesion of third nerve in diabetes usually spare the pupil,
comparing with surgical lesion(aneurysm …) which involve the pupil
The microangiopathy which involves the vasa nervorum , causing ischemia of the main trunk of nerve,
While spare the pial vessels which supply the superficial Pupillomotor parasympathetic fibers
Pupil abnormalities Rigid pupils – difficult mydriasis: The cause is an autonomic neuropathy, partially denervating both the sphincter and the dilator muscles
IrisHydrops of the iris
Rubeosis iridis :• Neovascularization of iris
• Retinal hypoxia
• Release of vasoproliferative substance
(angiogenic factor)
Intraocular Pressure Glaucoma :• Diabetics are 40% more likely to be diagnosed with POAG
• A complication of Rubeosis of the iris
A low intraocular pressure : is associated with diabetic acidosis
Lens Refractive error : 20-40% patients report vision changes when first
diagnosed
Collection of the sugar alcohol sorbitol in the lens, due to increased aldose reductase activity , causes the lens to swell and changes its refractive power
MYOPIA SHIFT:
Increase in blood sugar level
Hyperglycemia
Increase in osmotic pressure of crystalline lens
Increase in refractive index of lens
HYPERMETROPIC SHIFT:
Decrease in blood sugar level
Hypoglycemia
Decrease in osmotic pressure of crystalline lens
Decrease in refractive index of lens.
Cataract :
Cataract is one of the major cause of vision impairment in people with diabetes Diabetics are 60% more likely to be develop cataract
It occurs 10-20 years after the onset of insulin dependent diabetes
Control of the diabetes with restoration of normal blood glucose levels stops progression of the opacity
• True diabetes cataract (snow-flake/snow-storm catarct)
• Pre-senile cataract
Vitreous • Increase syneresis and liquefaction
• The vitreous provides the support framework for the development of neovascular complexes
Diabetic Retinopathy • Retinopathy is the most important ocular complication of
diabetes
• Prevalence of DR of any severity in the diabetic population is 21.6% and prevalence of blindness due to DR is approximately 5%
presntaion after 10-15 y after 30 y0%
20%
40%
60%
80%
100%
120%
0%
40%
100%
5%
85%
100%
Duration and Diabetic retinopathy
Type 1 Type 2
When does Diabetic Retinopathy arise..?
RISK FACTORS • Duration of DM
• Control of DM. Will not prevent but delays
• Hypertension
• Renal Disease
• Pregnancy
• Obesity, hyperlipidaemia, smoking, anaemia
•
PATHOGENESIS
CLASSIFICATION Non-proliferative :
Proliferative :• Mild-moderate• High risk• Advanced diabetic eye disease
Mild Moderate Severe
Nonproliferative diabetic retinopathyMild :
Indicated by the presence of at least 1 micro aneurysm
Moderate:
Includes the presence of hemorrhages, micro - aneurysms, and hard exudates Cotton wool spot
Microaneurysm
Exudate
Cotton wool
Severe:
The (4-2-1) rule; one or more of:• hemorrhages and microaneurysms in 4 quadrants• venous beading in at least 2 quadrants• intraretinal microvascular abnormalities in at least 1 quadrant
IRMA
Beading
Proliferative diabetic retinopathy
severe non-proliferative DR and one or more of the following :
Neovascularization : NVE , NVD
Vitreous / Preretinal hemorrhage
NVD
Neovascularization
Diabetic papillopathy • Diabetic papillopathy is an uncommon ocular manifestation
of diabetes mellitus (DM)
• The underlying pathogenesis is unclear but it maybe the result of small vessel disease
• Presentation is usually with mild optic nerve dysfunction and slow progression
• VA: 6/12 or better
• Non specific unilateral or bilateral mild disc swelling and hyperemia
• It usually resolves spontaneously within several months
Ocular changes during gestational diabetes• Progression of pre-existing diabetic retinopathy• Risk factors:• Type 1 diabetes• Longer duration of diabetes• Poor glycemic control• Greater severity of retinopathy at conception• Presence of hypertension of pre-eclampsia• Pregnancy itself
• Increased severity of DR- Poor fetal outcome
Key points• Women with diabetes who develop diabetic retinopathy during
pregnancy have high rate of spontaneous post-partum regression
• Patients with severe proliferative or non-proliferative diabetic retinopathy prior to conception have high risk of progression during pregnancy
• Brisk tightening of glycemic control has been associated with a greater risk of diabetic retinopathy progression
Caused by :
Maculopathy
Vitreous hemorrhage
Retinal detachment
Visual loss in diabetic retinopathy :
Maculopathy :
Main cause to visual loss in diabetic retinopathy
edema
ischemic
exudate
Macularpathy
Cotton wool
exudate
ischemic
Normal
OCT
Normal Macular edema
Vitreous hemorrhage
Retinal detachment
Management Medical treatment
Observation
Laser therapy
Anti VEGF
Vitrectomy
Medical treatment:
glucose control : controlling diabetes reduces DR by 54% & DME by 23%
Level of activity :maintaining a healthful lifestyle with regular exercise can help reduce the complication of diabetes and DR
Control your ABC’s..!! Hb A1C Blood pressure control Cholesterol level- Lipid-lowering therapy
STOP SMOKING..!!
Follow up:
Suggested follow-up Retinal finding
Annually Normal
1 year Mild NPDR
6 months - 1year Moderate NPDR
Every 4 months Sever NPDR
Every 2-4 months DME
Every 2-3 months PDR
Laser therapy:
Gold standard treatment- reduces severe visual loss
reduces legal blindness by 90% in people with severe nonproliferative or proliferative retinopathy
Indications: Proliferative diabetic retinopathy PRPDiabetic macular edema focal laser
Panretinal photocoagulation PRP
Panretinal photocoagulation (PRP)
Before After
Focal laser
Before After
Anti VEGF
Bevacizumab Avastin ®
Ranibizumab lucentis®
Aflibercept Eylea®
Avastin ® : BevacizumabIs part of a class of drugs that block the growth of abnormal blood vessels
Was initially approved by (FDA) as a treatment for different types of cancer
Its use “off-label” to treat eye disease such as DR, RVO and wet-AMD
This drug can stop the blood vessels leaking and growing
OCT before (a) and one month after (b) intravitreal Bevacizumab(Avastin) in a 44 year old diabetic patient with macular edema resolved after 1 month
Avastin benefits in DR includes PDR and DME
It could complement the focal photocoagulation in DME,
and an adjuvant agent to PRP in PDR therapy
Vitrectomy:
Removes blood
Removes Traction
Allows PRP
Vitrectomy
Summary • Ocular disease in diabetics are wide spectrum of symptoms that are
often overlooked given their varying mode of presentation
• Virtually all structures of eye can be affected by diabetes secondary to micro-angiopathy or increased susceptibility to infection
• Early detection of warning signs and regular screening for DR can prevent the early onset or delay the onset of blinding complications (PDR changes)
• Onset of DR changes also gives information about the possible damage to other end organs
• “Diabetes can be controlled and does not have to keep people from
achieving their dreams”- Michael Hunter
- World’s only insulin-dependent air show stunt pilot- First diabetic person to receive the Federal Aviation Administration
Low altitude airshow license
Thank you
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