visual impairment

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Whatever you may Whatever you may look like, marry look like, marry a man your own a man your own age - as your age - as your beauty fades, so beauty fades, so will his will his eyesight. eyesight.

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Page 1: Visual Impairment

Whatever you may Whatever you may look like, marry a man look like, marry a man your own age - as your your own age - as your beauty fades, so will beauty fades, so will

his eyesight.his eyesight.

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You know you're You know you're getting old when the getting old when the

candles cost more than candles cost more than the cake!the cake!

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The spiritual eyesight The spiritual eyesight improves as the improves as the

physical eyesight physical eyesight declines. - Platodeclines. - Plato

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Visual Impairment Visual Impairment in the elderly… .. .in the elderly… .. .

Geriatrics Grand RoundsGeriatrics Grand Rounds

2424thth March 2006 March 2006

Dr.Seraphine SoosaimanickamDr.Seraphine Soosaimanickam

Geriatrics FellowGeriatrics Fellow

Hackensack Medical CentreHackensack Medical Centre

UMDNJUMDNJ

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OBJECTIVES

Know and understand: The leading causes and pathophysiology of

visual loss Techniques for preventing and treating visual

loss The signs of and treatments for common eye

disorders in older persons Techniques for low-vision rehabilitation

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TOPICS

Causes of visual loss– Cataract– Age-related macular degeneration– Diabetic retinopathy– Glaucoma– Refractive error– Ischemic optic neuropathy

Keratitis sicca Lid abnormalities Herpes zoster ophthalmicus

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VISUAL IMPAIRMENT

Visual impairment (acuity < 20/40)– Prevalence increases with age.– 20% to 30% of those aged 75+ years

Blindness (acuity < 20/200)– Prevalence: 2% of those aged 75+ years– 50% of blind population is aged 65 and older.

Visual impairment is associated with falls, car crashes, inability to perform ADLs, quality of life.

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CATARACT

Cataract is a clouding of the natural lens, the part of the eye responsible for focusing light and producing clear, sharp images.

The lens is contained in a capsule. As old cells die they become trapped within the capsule.

Over time, the cells accumulate causing the lens to cloud, making images look blurred. For most people, cataracts are a natural result of aging.

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CATARACT

Prevalence: 20% of age group > 65 years; 50% of age group >75 years

Symptoms include increased glare, decreased contrast sensitivity, visual acuity

Risk factors: decreased vitamin intake, light (ultraviolet B) exposure, smoking, alcohol use, long-term corticosteroid use, diabetes mellitus

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Normal Vision

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Vision with Cataract

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CATARACT

Treatment: surgical extraction– 90% of patients achieve vision 20/40 or

better.– 1.5 million surgeries are performed annually

in US.– Local or topical anesthesia, sonographic

breakdown and aspiration of the lens, placement of an artificial lens

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SURGERY Under an operating microscope, a small

incision (3 mm) is made in the eye.

Tiny surgical instruments are used to break apart and remove the cloudy lens from the eye.

The back membrane of the lens (called the posterior capsule) is left in place.

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Cataract surgery

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CAPSULORHEXIS

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Capsulorhexis

The surgeon creates an opening in the capsule, which is a micro-thin membrane surrounding the cataract. This procedure is called capsulorhexis.

It requires extraordinary precision since the capsule is only about four-thousandths of a millimeter thick! (thinner than a RBC)

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Phacoemulsification

Phacoemulsification is the procedure in which ultrasonic vibrations are used to break the cataract into smaller fragments.

These fragments are then aspirated from the eye.

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Phacoemulsification

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Phacoemulsification

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Irrigation/aspiration

First the denser central nucleus of the cataract is removed.

Then the softer peripheral cortex of the cataract is removed using an irrigation/aspiration handpiece.

The posterior capsule is left intact to help support the intraocular lens (IOL) implant

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Irrigation/aspiration

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IOL IMPLANTATION

The intraocular lens is folded and passed through the tiny incision inside the “capsular bag”.

In the following illustration, the lens is being inserted via an “injector”. This instrument keeps the incision small while allowing implantation of a 6 mm lens through a 3 mm (or even smaller) incision

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IOL IMPLANTATION

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Intra Ocular Lens

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Intra Ocular Lens

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Intraocular implant

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Age-related macular degeneration

• It is a degenerative condition of the macula (the central retina).

It is the most common cause of vision loss in the United States in those 50 or older

Prevalence increases with age

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Pathophysiology

ARMD is caused by hardening of the arteries that nourish the retina.

This deprives the retinal tissue of oxygen and nutrients that it needs to function and thrive.

As a result, the central vision deteriorates.

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AGE-RELATED MACULAR DEGENERATION

• Risk factors: age, genetics, smoking, hypertension, fair skin

Diagnosis: presence (early) of drusen and (late) of choroidal neovascularization

Treatment is controversial– Vitamins, antioxidants, zinc– Prophylactic laser therapy– Photodynamic therapy

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Vision with macular degeneration

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Symptoms of Macular degeneration

The classic symptoms are

Decreased central visual acuity, Metamorphopsia or image distortion, and a central scotoma

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Dry macular degeneration

The dry type is much more common Typically results in a less severe, more

gradual loss of vision. Characterized by drusen and loss of

pigment in the retina. Drusen are small, yellowish deposits

that form within the layers of the retina. 

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Non-Exudative macular degeneration

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Drusen

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Drusen The drusen allow an angiogenic stimulant

(such as vascular endothelial growth factor) to promote the growth of underlying choroidal blood vessels into the subretinal space and retina.

These tufts of neovascularization are fragile and have a propensity to leak and bleed, eventually forming a fibrovascular scar and resulting in irreversible vision loss

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Exudative macular degeneration

Patient with wet macular degeneration develop new blood vessels under the retina. 

This causes hemorrhage, swelling, and scar tissue but it can be treated with laser in some cases

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Exudative macular degeneration

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ARMD with subretinal hemorrhage

Choroidal neovascularization and subretinal hemorrhage in a patient with late maculopathy.

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Angiographic diagnosis Hallmark of diagnosis of choroidal

neovascularization has been the fluorescein angiogram .

It pinpoints the location and extent of neovascular membranes and can guide laser photocoagulation.

Unfortunately, only about 13% of angiograms show a treatable localized lesion, or "classic" choroidal neovascularization. The other 87% show diffuse,, hyperfluorescent lesions that are not amenable to laser photocoagulation

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Iodocyanine green dye technique

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Treatment

Currently there are no treatments or preventive measures, other than vision aids, for patients with dry macular degeneration.

The only clinically proven treatment for wet macular degeneration is laser photocoagulation

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Laser treatment

Laser treatment guidelines vary, depending on the proximity of choroidal neovascularization to the fovea.

The common types of lesions are extrafoveal (200 to 2,500 micrometers from the fovea), juxtafoveal (1 to 199 micrometers from the fovea), and subfoveal (directly below the fovea).

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Laser Photocoagulation

Laser photocoagulation is a destructive treatment in which tissue is ablated by heat.

This treatment quandary was investigated by the multicenter group

Their studies indicate that although patients treated with laser showed an immediate decrease in vision,

-20% of treated eyes had severe vision loss after 3 years,

-compared with 37% of untreated eyes.

However, the final visual acuities were very poor for both groups (20/320 for treated and 20/400 for control subjects

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Photodynamic therapy It is still experimental. Photodynamic therapy, uses a

photosensitive dye, which, when activated in the retinal vasculature by a light source, produces a thrombus that closes neovascular vessels.

Since the immunologic and coagulating systems naturally break down thrombi, this therapy may be a fast-acting temporizing measure, rather than a long-term treatment

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Recommendations for ARMD • Use a halogen light. These have less glare

and disperse the light better • Shine the light directly on your reading

material. This improves the contrast and makes the print easier to see.

Use a hand-held magnifier. Try large-print or audio books. Most

libraries and bookstores have special sections reserved for these books.

Consult a low vision specialist. -specially trained to help visually impaired patients improve their quality of life.

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DIABETIC RETINOPATHY

• Among persons who have had type 2 diabetes for at least 10 years:– 70% show retinopathy.– nearly 10% show proliferative disease.

Duration of disease and control of blood sugar are the most important variables.

Prevention: Tight glucose control and blood pressure control (≤ 130/80)

Treatment: Panretinal laser photocoagulation inhibits growth stimulus for neovascularization.

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DIABETIC RETINOPATHY STAGES

Nonproliferative

Preproliferative

Proliferative

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DIABETIC RETINOPATHY: NONPROLIFERATIVE STAGE

Microaneurysms

Intraretinal hemorrhages

Exudates

Macular edema

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DIABETIC RETINOPATHY: NONPROLIFERATIVE STAGE

Intraretinal edema and exudate in the superior macular region with type 2 diabetes.

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DIABETIC RETINOPATHY: PREPROLIFERATIVE STAGE

Progressive ischemia Hemorrhages Venous caliber changes Intraretinal microvascular abnormalities Capillary nonperfusion

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DIABETIC RETINOPATHY: PROLIFERATIVE STAGE

Neovascularization of the retina

Neovascularization of the disc

Neovascularization of both

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DIABETIC RETINOPATHY: PROLIFERATIVE STAGE

Neovascularization of the disc in a patient with proliferative retinopathy.

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GLAUCOMA

Affects > 2.25 million Americans aged >40 years

Second most common cause of blindness worldwide. Most common cause of blindness among black Americans

$1 billion for glaucoma-related Medicare and Medicaid payments and disability

Defined as characteristic optic nerve head damage and visual field loss

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Progressive optic nerve damage

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Glaucoma

Progressive optic nerve damage (indicated by the cup to disc ratio) caused by glaucoma. 

Notice the pale appearance of the nerve with the 0.9 cup as compared to the nerve with the 0.3 cup.

Grading is done by cup to disc ratio.  (the depressed area in the center of the nerve) to the entire diameter of the optic nerve. 

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Vision with glaucoma

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Vision with Glaucoma The object you focus will appear clear -

with an area to the side of your focus which will be blurry.

If you gaze at the blurry area it becomes crisp and now a different area on side will become blurry.

It is difficult to perceive early peripheral visual field defects .

Hence glaucoma is called the ‘sneak thief of vision’.

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GLAUCOMA

Primary open-angle glaucoma is the most common type.

Slow aqueous drainage leads to chronically elevated intraocular pressures.

Patients are asymptomatic and may suffer substantial visual field loss before consulting a physician.

Causes are multifactorial and polygenic.

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Glaucoma Primary angle closure glaucoma (acute

glaucoma) occurs much more rapidly when the flow of fluid inside the eye cannot pass through the pupil,

causing a rapid rise in pressure inside the eye. Characterised by pain, redness and reduced

vision. The pupil of the eye is dilated. The cornea is usually swollen, causing the haloes

round lights and blurring of vision

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Glaucoma Management:

Intraocular pressure-lowering medications (local and systemic, eg, latanoprost and brimonidine)

Argon laser trabeculoplasty Intraocular surgery +/- antimetabolites

(5-fluorouracil, mitomycin-C) Drainage devices Ciliary body destructive procedures

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REFRACTIVE ERROR

Leading cause of visual impairment

Treatment: eyeglasses, contact lenses, laser refractive surgery

Ametropia – Myopia (nearsightedness)– Hyperopia (farsightedness)– Astigmatism (visual distortion)

Presbyopia ( ability to focus at near objects)– Begins after age 40– Caused by gradual hardening of the lens and decreased

muscular effectiveness of the ciliary body

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Snellen chart

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REFRACTIVE ERROR

Each line of the eye chart is assigned a notation in the form of a fraction that represents your visual acuity. 

The numerator is the distance in feet the patient is from the eye chart. 

The denominator represents the distance an eye with “normal” vision can read the same line. 

Interpreting the numbers is simple.  If you can read the 20/40 line, you’re able to see at 20 feet what a normal eye could see at 40. 

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ANTERIOR ISCHEMICOPTIC NEUROPATHY

Microvascular occlusion of the blood supply to the optic nerve

Due to atherosclerotic vascular disease or inflammation (temporal arteritis)

Results in acute vision or field loss

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ANTERIOR ISCHEMICOPTIC NEUROPATHY

Pallid swelling of the optic nerve head in a patient with anterior ischemic optic neuropathy.

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KERATITIS SICCA

Tear production decreases with age

Characteristics: redness, foreign body sensation, and reflex tearing

Management: replacement of tears (artificial tears during daytime and ointment at bedtime)

Temporary or permanent punctal plugs may retard tear egress in severe cases.

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LID ABNORMALITIES

Common among older adults

Gradual loss of elasticity and tensile strength that develops with age

Blepharochalasis (drooping of the brow) and blepharoptosis (drooping of the eyelid) may cause cosmetic deformity and, if severe, may impair vision.

Lid ectropion (eversion) or entropion (inversion) may cause discomfort.

Treatment: surgery

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HERPES ZOSTER OPHTHALMICUS

Painful reactivation of varicella zoster virus

Affecting the ophthalmic division of the trigeminal nerve

Hutchinson’s sign: lesions on the tip of the nose

Oral acyclovir may shorten the course.

Post-herpetic neuralgia may be debilitating; treat with local ointments (capsaicin, lidocaine) or systemic medications (corticosteroids, tricyclic antidepressants).

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Herpes zoster Ophthalmicus

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LOW-VISION REHABILITATION

Available to patients with acuity < 20/60

Improved lighting and selection of reading material with bold, enlarged fonts and accentuated black-on-white contrast

Magnification: high-plus spectacles, magnifiers, closed-circuit television, telescopic devices

Eccentric viewing for macular degeneration patients with central macular pathology : training to use off-center fixation

Talking devices or Braille for those who have lost vision altogether

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SCREENING TO PREVENT VISUAL LOSS

Comprehensive eye examinations are recommended every 1 to 2 years for persons aged 65 years and older.

(By the American Academy of Ophthalmology

and USPSTF)

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SUMMARY

Visual loss occurs commonly among older adults

Leads to reduced quality of life, high medical care costs, and loss of independence

Primary care providers should routinely screen older adults for visual loss

Treatment options are available for many types of visual loss

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THANK YOU!THANK YOU!