Hereditary eye dysfunction

Hereditary eye dysfunction
 The four most common eye conditions leading to loss of vision or
blindness are:
 Cataracts.
 Diabetic retinopathy.
 Glaucoma.
 Age-related macular degeneration.

An ocular opacity, partial or complete, of one or both eyes, on or in the lens
or capsule, especially an opacity impairing vision or causing blindness. The
subsequent cloudy appearance of the eye resulted in the origin of the name
cataract SURES - IN HOUSE CLINIC

Signs and symptoms of cataracts include
• Clouded, blurred or dim vision
• Increasing difficulty with vision at night
• Sensitivity to light and glare
• Need for brighter light for reading and other activities
• Seeing "halos" around lights
• Frequent changes in eye glass or contact lens prescription
• Fading or yellowing of colors
• Double vision in a single eye

Causes
 Most cataracts develop when aging or injury changes the
tissue that makes up your eye's lens.
 Some inherited genetic disorders that cause other health
problems can increase your risk of cataracts.
 Cataracts can also be caused by other eye conditions, past eye
surgery or medical conditions such as diabetes.
 Long-term use of steroid medications, too, can cause
cataracts to develop.

Management
 Vision may be improved by: Using different eyeglasses ------
Magnifying lenses
 Cataract Surgery
Draw back: High pressure in the eye • Blood collection
inside the eye • Infection inside the eye
 Intake of dietary antioxidants prevent cataract formation by
blocking the oxidative modification of the lens Vitamins A, C
and E
 Phacoemulsification: The most common method of
removal. Phaco involves a small incision on the side of the
cornea

DIABETIC RETINOPATHY
RISK FACTORS
1. Duration of diabetes
2. Poor control of Diabetes
3. Hypertension
4. Nephropathy
6. Obesity and hyperlipidemia
7. Smoking
8. Pregnancy

Pathogenesis
 Microangiopathy which has features of both microvascular leakage and
occlusion
 Larger vessels may also be involved
 Loss of pericytes results in distention of weak capillary wall producing
microaneurysms which leak.
 Blood-retinal barrier breaks down causing plasma constituents to leak
into the retina – retinal oedema, hard exudates
 Basement membrane thickening, endothelial cell damage, deformed
RBCs, platelet stickiness and aggregation
 Vascular Endothelial Growth Factor (VEGF) is produced by hypoxic
retina
 VEGF stimulates the growth of shunt and new vessels

Classification of DIABETIC RETINOPATHY
(DR)
I Non-proliferative DR (NPDR)
 Mild
 Moderate
 Severe
 Very severe
II. Proliferative DR (PDR)
III. Clinically significant macular oedema (CSME)
- May exist by itself or along with NPDR and PDR

Refractive Errors
Hyperopia (Far Sightedness)
 Object focuses behind the
retina
 Able to see only far objects
Signs and symptoms:
 blurred vision, Squinting,
Eye rubbing, Headaches
Treatment: Convex lens
Myopia (Near Sightedness)
 Object focuses in front of the
retina
 Able to see only close objects
Symptoms and Signs: Blurred
vision, squinting, eye rubbing,
headaches
Treatment
 Concave lens and Radical
keratotomy

Refractive Errors Cont…..
Astigmatism
 Abnormal shaped cornea (egg
shape instead of spherical)
 Object is partially clear & other
blurred
 Symptoms and Signs: blurred
vision, squinting, eye rubbing,
headaches
Treatment
 Concave lens and Radical
keratotomy
Presbyopia
 Mechanism
Rigidity of the lens (old
age)
unable to focus
 Symptoms and Signs:
Blurred vision, squinting,
eye rubbing, headaches
 Treatment: Lens transplant