Cataract.ppt by sir azmat jehan for optometrists

Cataract.ppt by sir azmat jehan

1. Cataract
By.
AZMAT JEHAN

2. •Cataract derives from latin word cataracta
meaning (water fall).
•In greek words ketarrahtes meaning (down
rushing) or (to dash down )as rapidly running
water turns white.
•dash means sudden rush or movement.

3. CATARACT
•Opacification of lens fibers or its capsule is
called cataract.
Classification
It can be classified on the following basis:

4. According to age of onset
•Congenital
•Adult
•Age-related

5. According to location of opacity
Nuclear
Cortical
Sub capsular (posterior or anterior)

6. Cortical

7. Mature

8. Nuclear

9. According to degree of opacity
•Immature- some clear fibers remain .
•Intumescent- when the lens with cataract
swells up with water.
• Mature – when the whole lens becomes
opaque

10. Causes of Cataract :
•Traumatic – due to trauma .
•It is the commonest cause of unilateral
cataract in young people.
• The different kinds of trauma that can cause
cataract are:

11. •Direct Penetrating injury - disposable syringe,
needle etc.
•Blunt trauma –
•Electric shock and lightning are rare causes.
•Radiation ( given for tumours)

12. Toxic Cataract
•due to substances that are toxic to the
lens like ,Steroids ,chlorprozamine etc
•Systemic disease like diabetes.which
develop earlier in age.

13. Secondary cataract
•A Secondary (complicated ) cataract as a
result of other primary ocular disease.
•Like chronic anterior uveitis ,mainly by
synechea .
•Acute angle closer glaucoma.

14. AGE RELATED CATARACT (ARC)
•Change in the lens with ageing include Protein aggregation
•Disturbance of the permeablity of capsules.
•Increased production of insoluble protein
•Lipids in the lens increase.
•Disturbance of lens metabloismdue to disturbed PH or other
Substances that provide safety against oxidative damage
decrease like vitamin C and ( glutathione )

15. •Nuclear mass increases.
•UV light damages lens fibres with advancing age.
•All these changes lead to progressive
opacification of lens fibers & ARC.
Whatever the cause the lens undergoes two process
1.Hydration where drops of water apperars betweenthe fibres.
2.Coagolation of lens protein

16. Clinical Features:
•Usually starts appearing after the age of 50.
•Can be unilateral / bilateral
•Dimness of vision (DV) gradual DV without any pain .
•Quality of vision may vary with the time of the day &
degrees of brightness .
• Glaring especially in sub capsular cataract
• due to scattering of light very trouble some especially if the
patient is a driver

17. • An earliest change is an increase in the
refractive index of lens so that there is a
decrease in hyperopia or an increase in
myopia
•but as the cataract advances both near & for
vision decrease .

18. COMPLICATIONS OF ARC:
Uveitis
•lens proteins can leak out & induce
inflammation of the eye as Uveitis .
Glaucoma
•Swelling of the lens can push the iris forward
& cause an ACG

19. MANAGEMENT:
HISTORY
•Onset
•Duration Symptoms
•Severity
•History of any other eye disease

20. Aphakia
•Aphakia is a condition in which the crystaline
lens is absent from its normal position.
•It may be by operation.
•By trauma
•By couching methd.
•As developmental anomaly-congenital
absence of the lens.

21. Subluxation and dislocation of lens
•Subluxation.when a few fibres of the
suspensory ligamentsare torn ,the lensis said
to be subluxated but it still remaines in the
pupillary area. If it is a normal lens,it remains
clear even after sublaxation.
•Dislocation: when all the fibers of the
suspensry legament are torn, the lens is said
to be dislocated .a dislocated lens may drop in
the vitreous posterior dislocation ,the lens
may come in to the anterior chamber .

22. Causes of Subluxation and dislocation of
lens
•Injury
•Hypermature catarct
•Congenital weakness of the sussuspensory
ligament

23. •In 1748, Jacques Daviel was the first modern
European physician to successfully extract
cataracts from the eye.
•In the 1940s Harold Ridley introduced the concept
of implantation of the intraocular lens which
permitted more efficient and comfortable visual
rehabilitation possible after cataract surgery.

24. ,
•In 1967, Charles Kelman introduced phaco
emulsification, a technique that uses
ultrasonic waves to emulsify the nucleus of
the crystalline lens in order to remove the
cataracts without a large incision. This new
method of surgery decreased the need for an
extended hospital stay and made the surgery
ambulatorial. Patients who undergo cataract
surgery hardly complain of pain or even
discomfort during the procedure. However
patients who have topical, rather than
peribulbar block, anesthesia may experience
some discomfort.

25. Treatment
•Treatment for cataract is surgical removal of
the lens
•Correct time for the removal of the lens is
when the loss of vision becomes a handicap
for the patient
•People have different visual requirements.
•A middle –aged professional man is likely to
need cataract removal at an earlier stage than
an old illiterate villager.

26. COUCHING
•Couching has been the traditional treatment of
cataract for thousand of years it is thought to have
originated in india and was the only method until the
arrival of modren cataract surgery .the coucher
insert a needle or thorn in to the eye ,either at the
limbus or a few millimeter behind it .this rupture the
suspensory ligament and pushes the lens bck down
in to the vitreous.couching is still quite common in
some isolated ruler areas of north and central africa
and asia where no medical servies.most couchers are
uneducated ,and travel from village to
village ,performing a few operation and then moving
on.

28. Cataract Surgery
•Intracapsular Cataract Extraction (ICCE)
•In an (ICCE) the entire lens is removed.
•After removing the lens a small piece of iris is
excised to allow the aqueous to continue to
circulate in the eye.
•After ICCE the anterior face of the vitreous
may completely occlude the pupil.

29. Extra capsular cataract extraction
•In ECCE the posterior capsule and the
suspensory ligament is left intact.
•The anterior capsule is incised and the nucleus
is expressed out of the eye.
•The rest of the lens cortex is removed by using
a two way irrigation syringe and leaving only
the posterior capsule.

30. •The intact posterior capsule leaves the vitreous and
the retina more stable and

•Forms a layer onto which an IOL can be implanted.
•The main post-op complication of ECCE is that the PC
may thicken to form an opaque membrane and the
patient cannot see clearly

31. Complication of cataract surgery
•Endophthalmitis. This is disastrous complication
usually occuring in within the first 48hrs
postoperatively. Urgent treatment is needed.
•Retinal detachment. This is more likely to occur if
there has been any loss of vitreous during
operations or if the patient is myopic. Extracapsular
extraction greatly reduces the risk of retinal
detachment. Because the posterior capsule keep
the vitreous in its place.

32. •Cystoid macular edema. This causes edema and cystic
changes in the macula and occurs about 2-6 weeks
postoperatively.
•Bullous keratopathy. This is the name given to serve
corneal edema which may occur after cataract surgery. It
is due to a loss of corneal endothelial cells so that the
cornea becomes waterlogged. It is nearly always the
result of poor surgical technique.
•Thickening of the posteior lens capsule. This only occur
following extracapsular extraction and usually from
6months to 3yrs posporativevly. About 25% of patients
having an extracapular extraction will develop some
thickening of the posterior capsule sufficient to cause
significant loss of vision, but this complication can be
treated fairly easily by making small hole in posterior
capsule .