Cataracts are opaque areas that develop in the lens of the eye. They are the most common cause of treatable blindness in dogs. Cataracts occur when the lens becomes cloudy, preventing light rays from properly focusing on the retina. They are typically age-related but can also be caused by diabetes, trauma, toxins or other metabolic diseases. Surgical removal of the cataractous lens, called phacoemulsification, is the most common treatment to restore vision.

1. Cataract
Opacity of lens is known as cataract
Cataracts are the most common cause of
treatable blindness in dogs

2.  severe cataracts
cause blindness
 By disrupting the
ability of the lens to
focus light rays
onto the retina
 toy poodle,
miniature and
standard poodle,
English cocker

3.  Spaniel, Boston
terrier, golden
retriever, rottweiler,
Labrador retriever,
 Miniature
schnauzer, bichon
frise, and chow
chow

4.  prevalence of cataracts increases with age
in dogs
 Diabetes mellitus is the second most common cause
of
cataracts in the dog
 less common causes include other metabolic
diseases, toxins, drugs, congenital abnormalities,
dietary deficiencies,
 trauma, radiation therapy, and aging

5. Tapetum
Eyeshine
occurs in a
wide variety of
colors
including blue,
green, yellow,
pink and red.

6.  Incipient cataracts
involves <10% to 15%
of the lens

7.  Immature cataracts vary widely in
appearance and may affect only a small
portion of the lens to almost the entire lens

8.  By definition,
 a tapetal reflection is apparent with
immature cataracts, although
 vision may be diminished if the cataract is
well developed.

9. A mature cataract
affects the entire lens
A mature cataract
appears as a solid
white opacity of the
lens, and affected dogs
are severely impaired
visually

11.  Hypermature cataracts
have undergone
liquefaction and
resorption
Hypermature cataracts
often have a crystalline
appearancewith
wrinkling of the lens
capsule

12. A tapetal reflection may
or may not be present.
Vision with hypermature
cataracts is variable
depending upon the
degree of liquefaction.

13.  Congenital/ aquired
 Complete/ partial
 Stationary / progressive
 Senile/toxic
 Juvenile cataract – prognosis is good

14.  Capsular/ cortical/
lamellar(bet. Lens
nucleus and
cortex)/nuclear/diff
use(entire lens
substance)

15.  Themost common treatment for
cataracts is surgical removal by
phacoemulsification.(Phaco- lens
and emulsification- liquifying/
breaking)

16.  Tests indicated
 prior to surgery include a complete
ophthalmic examination,
 complete blood count, biochemical
panel, urinalysis, electroretinography
(ERG), and ocular ultrasonography.

17.  Discission/ Treatment
needling : ant .
Capsule is incised
in cruciate fashion,
using a cataract
needle –
aqu.humour in
contact with lens
substance-
facilitate resorption
– repeated many
times

18.  Removal of lens :
intracapsular (with
capsule)- difficult in
animals – sus.lig is
tough
 Extra capsular
(without capsule)-
successful

19. Procedure
 Extracapsular: fix the eye ball
 Canthotomy may be done to increase the
exposure
 Incise the cornea at limbus- graefe’s knife/
scissors
 Incise the anterior capsule of lens
 Catract scoop is used to remove the lens
substance
 Suture the corneal wound
 In man dissolution of the opaque lens by
using 0.02% trypsine has been reported.