diabetes and the eye nam

Post on 13-Apr-2017

122 Views

Category:

Health & Medicine

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

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

61

3

3

5

8

8

7

7

42

9

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

top related