Ophthalmology

1. CATARACT
11/18/2022
By dr. Omar S. Mahmood
M.B.CH.B F.I.C.M.S ( Opht.)

2. The crystalline lens
Anatomy of the lens
The crystalline lens is a biconvex, avascular transparent
structure enclosed by a capsule.
The lens consists of:
1- Nucleus:
2- Cortex:
3- The capsule:
What is zonules?
What is "Accommodation"

5. Ciliary muscle
• Innervation: 3rd CN
• Function ?
Ciliary process
• Attaches to the lens by
suspensory ligament
(zonular fibers)
• Secrete the Aqueous humor
into the post. chamber

6. Definition of cataract
• Opacification of crystalline lens

8. Epidemiology
1. Cataracts remain the
leading cause of blindness.
2. Age-related cataract is
responsible for 48% of
world blindness, which
represents about 18
million people
3. Cataracts are also an
important cause of low
vision in both developed
and developing countries.

9. Causes of cataract
• Old age (commonest)
• Ocular & systemic diseases
– DM
– Uveitis
– Previous ocular surgery
• Systemic medication
– Steroids
– Phenothiazines
• Trauma & intraocular
foreign bodies
• Ionizing radiation
– X-ray
– UV
• Congenital
– Dominant
– Sporadic
– Part of a syndrome
– Abnormal galactose
metabolism
– Hypoglycemia
• Inherited abnormality
– Myotonic dystrophy
– Marfan’s syndrom
– Rubella
– High myopia
9

10. Age -related cataract
It is the Most commonly occurred.
Classified according to:
 Morphological Classification
• Nuclear
• Cortical
• Subcapsular
• Christmas tree – uncommon
 Maturity classification
• Immature Cataract
• Mature Cataract
• Hypermature Cataract

13. 13

15. Mature Cataract
• Lens is completely opaque.
• Vision reduced to just perception of light
• Iris shadow is not seen
• Lens appears pearly white
Right eye mature cataract, with obvious
white opacity at the centre of pupil

16. Liquefactive/Morgagnian Type
• Cortex undergoes auto-lytic liquefaction and turns uniformly
milky white.
• The nucleus loses support and settles to the bottom.

17. Symptoms
• A cataract usually develops
slowly, so:
–Causes no pain.
–Cloudiness may affect only a
small part of the lens
–People may be unaware of any
vision loss.
• Over time, however, as the
cataract grows larger, it:
–Clouds more the lens
–Distorts the light passing
through the lens.
–Impairs vision
• Reduced visual acuity (near
and distant object)
• Monocular diplopia.
• Altered colours ( white
objects appear yellowish)
• Not associated with pain,
discharge or redness of the
eye.
• Cataract can improve vision?!

18. Signs
• Reduced acuity.
• An abnormally dim red reflex is seen when the eye is viewed
with an ophthalmoscope.
• Reduced contrast sensitivity can be measured by the
ophthalmologist.
• Only sever dense cataracts causing severely impaired vision
cause a white pupil.
• After pupils have been dilated, slit lamp examination shows the
type of cataract.

19. Gradual loss of vision
DDX:
1. Cataract
2. Glaucoma
3. Diabetic retinopathy
4. Hypertensive retinopathy
5. Age related macular degeneration
6. Retinitis pigmentosa
7. OnTrachoma
8. chocerciasis (river blindness)
9. Vitamin A deficiency

20. Treatment
 SURGERY● there is NO effective medical treatment
 Indications of surgery:
1. 1- Visual improvement:is the most common indication,
2. whether it is mature or immature.
3. 2- Medical indications ?
 Types of cataract surgery:
1. 1- Intracapsular cataract extraction (ICCE) ± AC IOL (anterior
chamber, intraocular lens):
2. 2- Extracapsular cataract extraction (ECCE) ± PC IOL (posterior
chamber intraocular lens):
3. 3- Phacoemulsification:

22. Phacoemulsification in cataract surgery
involves insertion of a tiny, hollowed tip that
uses high frequency (ultrasonic) vibrations to
"break up" the eye's cloudy lens (cataract). The
same tip is used to suction out the lens
.

24. Summery
• Cataract is opacification of crystalline lens
• Cataract can be congenital or acquired
• Cataract presents with gradual painless loss of
vision
• Senile cataract is the most common cause
• Treatment of cataract is only surgical when
indicated

25. Thank You