A review for medical students.

1. CATARACT
By: Qurat-ul-ain
Ophthalmic Medical
Technologist/ MBA Health &
Hospital management

2. CATARACT
CLASSIFICATION OF CATARACT
• According to location
• According to age at onset
• According to degree of opacity present
• According to rate of development
• On the basis of bi-microscopic appearance
• On the basis of any systemic disorder
It is a cloudiness or opacity in
the normally transparent
crystalline lens of the eye. Its
cloudiness can cause a
decrease in vision and may
lead to eventual blindness.

3. NUCLEAR CATARACT
 Myopic shift.
 Decrease in distance vision, difficulty in
night driving, monocular diplopia, and loss
of color discrimination ability.
 Gradual opacification of the central portion
of the lens nucleus.
 Age-related, sclerosis, yellowing or brown
to black darkening of the lens nucleus.

4. POSTERIOR SUB-CAPSULAR
CATARACT
 Glare and decreased visual acuity especially
during bright sunlight but see well in dim
illumination.
 Granular opacities in the posterior pole of cortex
 May be age related or occur as a complication
of other conditions such as intraocular
inflammation, steroid administration, vitreoretinal
surgery and trauma.
 May also be related to irradiation & systemic
conditions

5. ANTERIOR SUB-CAPSULAR POLAR
CATARACT
 May present as congenital or acquired cataract
secondary to uveitis or trauma.
 May or may not cause a significant visual
disturbance
 Small anterior polar opacification
 May involve only the capsule, sub-capsular area
or may be pyramidal and project into the anterior
chamber
 May occur anywhere in the pupillary region

6. CORTICAL
CATARACT
 Most common form of senile cataract
 Minimal symptoms of decreased VA
 Mild to severe glare and night vision difficulties
and may impair driving.
 When the lens opacities are in the visual axis
patient may complain of monocular diplopia.
 Opacities located in the cortical layer and starts
from the lower portion of the lens.
 Early stage – water clefts and vacuoles,
resulting in irreversible opacities.
 Advance stage – spoke like or wedge shape
peripheral opacities progress circumferentially.

7. ACCORDING TO AGE AT ONSET
Congenital/
Infantile
Occur in new born babies
for many reasons that can
include inherited
tendencies, infection,
metabolic problems,
diabetes, trauma,
inflammation or drug
reactions.
Juvenile/
Acquired
A soft cataract occurring
in a child or young adult,
usually congenital or
resulting from trauma.
Age-related
Occurs due to:
protein clumping or
Lens discoloration

8. DEGREE OF OPACITY
INCIPIENT
A very early stage of
development with no
impairment of vision.
IMMATURE
An incomplete cataract,
the lens is only slightly
opaque and the cortex
clear.
Hazy view of optic disc.
INTUMESCENT
A mature cataract that
progresses, the lens
becomes swollen from the
osmotic effect of
degenerated lens protein
and this may lead to
secondary angle closure
(acute) glaucoma.

9. Mature
Completely opaque lens
No disc view.
Hyper-mature
Lens begun to liquefy.
Swollen, milky cortex, the
result of autolysis of the
lens fibers of a mature
cataract.
Lens becomes either
dehydrated and flattened
or liquid and
soft with the nucleus at
the bottom of the
capsule.
An opaque lens that has
lost water and has
become soft and
reduced in size.

10. BI-MICROSCOPIC
APPEARANCE
Lamellar
Affecting only certain
layers between the cortex
and nucleus of the lens.
Coralliform
Congenital cataract with
round or elongated
processes radiating from
the centre of the lens.
Punctate
An incomplete cataract in
which there are opaque
dots scattered through
the lens.

11. ETIOLOGY
• Aging
• Congenital disorders
• Genetic abnormalities
• Maternal rubella during 1st trimester
• Traumatic
• Glaucoma
• Retinal detachment
• Diabetes mellitus
• Retinitis pigmentosa
• Hypo-parathyroidism
• Myotonic dystrophy
• Atopic dermatitis
• Exposure to ionizing radiation or infrared rays

12. DRUGS TOXIC
TO LENS
• Prednisone
• Ergot alkaloids
• Di-nitro phenol
• Naphthalene
• Phenothiazines
• Pilocarpine
• Exposure to ultraviolet rays

13. THANK YOU!