Download Macular Degeneration And Diabetic Retinopathy

Macular Degeneration and Diabetic
Retinopathy
Carmen Leyva
Vicki Herrin
Hampton Huddleston
Stephen F. Austin State University
What is Macular Degeneration?
• Macular Degeneration is the progressive
deterioration of the macula, the light-sensitive
cells of the central retina, at the back of the
eye. As the macular cells malfunction and die,
central vision becomes gray, distorted and is
eventually lost. Peripheral vision does not
become affected.
What is Macular Degeneration? (cont.)
• The macula contains the highest
concentration of photosensitive cells in the
retina. These cells transform light into
electrical signals that are sent to the brain for
processing into vision. Fine detail vision and
critical color vision are located in the macula.
The macula depend on nutrient diffusion from
the choroid layer. Anything that interferes
with this nutrient supply can lead to MD.
What Types of Macular Degeneration
Do We Have?
• Most Common
-Age-Related Macular Degeneration (AMD)
-It typically affects people age 50+
-It is the 3rd cause of blindness in the world
accounting for 9% of all blindness (3 million
persons)
-Number affected is expected to double by
the year 2020 as a result of aging
What Types of Macular Degeneration
Do We Have? (cont.)
• Less Common
Juvenile Macular Degeneration (JMD)-A group
of inherited disorders affecting children and
younger adults.
Cystoid Macular Degeneration-The development
of fluid-filled cysts or sacs in the macular region,
associated with aging, inflammation, or severe myopia.
Diabetic Macular Degeneration
Retinal Pigment Epithelial detachment-A rare
form of wet MD in which fluid leakage from the
choroid causes the detachment or disappearance of the
pigmented retinal epithelium.
What Are The Forms of AMD?
1. Dry Macular Degeneration (non-neovascular)
-More common with about 85% to 90% of
AMD patients diagnosed with dry AMD.
-Less serious
-A condition where fatty tissue slowly builds
up behind the retina and causes a gradual
loss of visual acuity.
What Are The Forms of AMD? (cont.)
2. Wet Macular Degeneration (neovascular)
-More serious
-In about 10% of cases, dry AMD progresses
to wet MD.
-A condition where new blood vessels grow
beneath the retina and leak blood and fluid.
This leakage causes permanent damage to
light-sensitive retinal cells, which die off and
create blind spots in central vision.
What Are The Two Categories of Wet
MD?
Two categories:
a.) Occult-New blood vessel growth
beneath the retina is not as pronounced,
and leakage is less evident; typically
producing less severe vision loss.
b.) Classic-When blood vessel growth and
scarring have very clear, delineated
outlines observed beneath the retina;
usually produces more severe vision loss.
What Are the Symptoms of AgeRelated Macular Degeneration?
• Requiring more light for reading
• Reduction, blurring, a blank spot, or loss of central
vision while peripheral vision is unaffected
• Difficulty recognizing faces
• Visual distortions such as the bending of straight lines
• Images appearing smaller
• Changes in color perception or abnormal light
sensations
• A decline of at least two lines in visual acuity as
measured on a standard eye chart. Ex. 20/20 vision
declining to 20/80
What Are the Causes of Age-Related
Macular Degeneration?
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Aging
Obesity and Inactivity
Heredity
High Blood Pressure (Hypertension)
Smoking
Lighter Eye Color
Drug Side Effects
How Is Macular Degeneration
Diagnosed?
• Although vision loss is irreversible, early
detection of MD may slow the progression of
dry to wet AMD.
• Usually AMD is often fairly advanced by the
time an ophthalmologist is consulted.
• Following the diagnosis of MD, the doctor may
perform additional tests to determine the
location and extent of the disease.
How Is Macular Degeneration
Diagnosed? (cont.)
• Tests used:
Eye Exam
Amsler Grid Test
Fluorescein Angiography
Indocyanine Green Angiography (IGCA)
Optical Coherence Tomography (OCT)
Genetic Testing
What Is the Treatment For Age-Related
Macular Degeneration?
• Dry Macular Degeneration
-No treatment available to reverse Dry MD
-Progression of Dry MD can be slowed by
taking high doses of vitamins A, C, and E
and the minerals zinc and copper
What Is the Treatment For Age-Related
Macular Degeneration? (cont.)
• Wet Macular Degeneration
-The doctor prescribes treatment based on
the location and extent of the abnormal
blood vessels
Treatments used:
-Anti-angiogenic Therapy (injectable drug
treatment
-Photocoagulation (laser surgery)
-Photodynamic Therapy (injectable drug
treatment)
-Submacular Hemorrhage Displacement Surgery
What is Diabetic Retinopathy?
• Diabetic Retinopathy is the most common
diabetic eye disease and it is caused by
changes in the blood vessels of the retina
• In some people with diabetic retinopathy,
blood vessels may swell and leak fluid
• In other people, abnormal new blood vessels
grow on the surface of the retina
What is Diabetic Retinopathy? (cont.)
• It is the 4th cause of blindness in the world
accounting for 5% of all blindness (1.8 million
persons)
• At least 171 million people worldwide have
diabetes and this number is likely to increase more
than double by 2030 to 366 million
• After 15 years about 2% of persons with diabetes will
become blind and 10% will develop severe visual loss
• After 20 years more than 75% will have some form
of diabetic retinopathy
What Are The Stages of Diabetic
Retinopathy?
1. Mild Nonproliferative Retinopathy-Earliest Stage
-Microneurysms occur
2. Moderate Nonproliferative Retinopathy-Blockage of blood vessels that nourish the retina
3. Severe Nonproliferative Retinopathy-Blockage of many more blood vessels
4. Proliferative Retinopathy-Advanced Stage
-Triggering growth of new blood vessels by the
signals sent by the retina for nourishment
What Are the Causes of Diabetic
Retinopathy?
• Blood vessels damaged from diabetic retinopathy
can cause vision loss in two ways:
1. Proliferative Retinopathy-The most advanced
state of the disease in which fragile and abnormal
blood vessels can develop and leak blood into the
center of the eye
2. Macular Edema-Fluid can leak into the center
of the macula causing swelling. This can occur at
any state of diabetic retinopathy, but it is more
likely to occur as the disease progresses.
What Are The Symptoms Of Diabetic
Retinopathy?
• Often there are no early symptoms in the early
stages of the disease
• Spots floating in vision (floaters)
• Blurred vision
• Fluctuating vision
• Dark or empty arenas in vision
• Poor night vision
• Impaired color vision
• Vision loss
How is Diabetic Retinopathy Detected?
• Comprehensive Eye Exam that includes:
-Visual Acuity Test
-Dilated Eye Exam
-Tonometry
-Fluorescein Angiogram-Only performed if
treatment for macular edema is needed.
How is Diabetic Retinopathy Treated?
• No treatment is needed during first 3 stages
unless there is macular edema. Important to
control levels of blood sugar, blood pressure,
and blood cholesterol to prevent progression.
1. Laser Surgery
2. Injection of Triamcinolone into the eye
3. Vitrectomy
Global Causes of Blindness Due To Eye
Diseases, Excluding Refractive Errors
1.
2.
3.
4.
5.
6.
7.
8.
9.
Cataract
Glaucoma
AMD
Diabetic Retinopathy
Corneal Opacities
Childhood Blindness
Trachoma
Onchocerciasis
Others
47%
12%
9%
5%
5%
4%
4%
1%
13%
10 Facts About Blindness and
Visual Impairment
1. Worldwide, about 314 million people are visually
impaired due to various causes;
45 million of them are blind.
2. 153 million are visually impaired because of
uncorrected refraction errors (near-sightedness,
farsightedness, or astigmatism). Almost all of them
could have normal vision restored with eyeglasses,
contact lenses or refractive surgery.
3. Over 85% of visually impaired people live in low- tomiddle-income countries.
4. 39% of all blindness is due to age-related cataract, the
leading cause of blindness.
10 Facts About Blindness and
Visual Impairment (cont.)
5. Cataract surgery and correction of refractive errors are
among the most cost-effective health interventions.
6. Age-related causes of visual impairment and blindness are
increasing, as is blindness due to uncontrolled diabetes.
7. Up to 80% of all blindness in adults is preventable and
treatable. Among children, the major causes of avoidable
blindness include cataract, retinopathy of prematurity
(ROP), and Vitamin A deficiency.
8. Blindness caused by infectious diseases is decreasing
globally due to public health action. Blinding trachoma
affects 40 million people today, compared to 360 million in
1985.
10 Facts About Blindness and
Visual Impairment (cont.)
9. Around 1.4 million children under the age 15 are
blind. Yet approximately half of all childhood
blindness can be avoided by treating diseases
early and by correcting abnormalities at birth
such as cataract and glaucoma.
10. For decades, the World Health Organization
(WHO) has been working with global partners to
eliminate the main causes of avoidable blindness,
strengthening country-level efforts by providing
technical assistance, monitoring, and
coordination.
References
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Macular Degeneration (n.d.). Retrieved July 29, 2010 from
http://www.answers.com/topic/macular-degeneration
Age-Related Macular Degeneration (n.d.). Retrieved July 29, 2010 from
http://www.allaboutvision.com/conditions/amd.htm
Macular Degeneration (n.d.). Retrieved July 29, 2010 from
Http://www.mayoclinic.org/macular-degeneration/
Diabetic Retinopathy (n.d.). Retrieved July 29, 2010 from
http://en.wikipedia.org/wiki/Diabetic_retinopathy
Facts About Diabetic Retinopathy (n.d.). Retrieved July 29, 2010 from
http://www.nei.nih.gov/health/diabetic/retinopathy.asp
What is Vision 2020? (n.d.). Retrieved July 31, 2010 from
http://vision2020.org/main.cfm?type=WHATVISION2020
10 facts about blindness and visual impairment (n.d.). Retrieved July 31, 2010 from
http://www.who.int/features/factfiles/blindness/blindness_facts/en/index.html
AMD is the commonest cause of blindness in industrialized countries
http://www.vision2020.org/main.cfm?type=WIBAGERELMUSCDEG
Diabetic retinopathy is responsible for 4.8% of the 37 million cases of blindness due to eye diseases
http://www.vision2020.org/main.cfm?type=WIBDIEBETIC