Page 66 - The Book Pi in eye

Rajesh Khanna, MD

main wound is constructed. At all time a real time scanning image of
the cornea and lens is displayed on the monitor. After the laser has
done its beautiful work the patient is taken to the operating room to
remove the lens fragments and insertion of the new pi.
There are various advantages of employing the laser. The surgeon
can plan the exact openings and pattern of breakup lens pieces he or
she desires. This plan is generated by performing various tests as
mentioned previously in chapter 5. These include obtaining a colored
image of the surface of the eye, and measuring the length of the eye.
A detailed clinical slit exam is very essential. The surgeon needs to
asses the thickness, color and hardness of the lens. Any weakness in
the support of the lens or abnormalities on the lens capsule has to be
meticulously looked for. Pupil dilation has to be taken into
consideration.
All the information obtained leads to a plan of action. This plan is
entered into the software of the laser. This can be analyzed and
contemplated upon in tranquility. Any modifications can be
programmed. In difficult cases a second opinion can be taken.
If the support of the lens is weak manipulating the capsule by
hand can lead to further weakening of the support. Laser cataract
surgery is safer as it does not stress the lens capsule or its support.
The same holds true in traumatic cataract cases where trauma
weakens the support. The laser is beneficial in making openings in
eyes with thick capsule like in children. In people with white or red
cataracts the capsule needs to be stained manually to be visualized
and still it may be difficult to get a good view of the capsule. The
laser overcomes this at it employs imaging in real time and cutting
vertically avoids any traction on the zonular support system.
The opening in the capsule can be controlled by the laser down to
a tenth of a millimeter. So the diameter can be made to vary over a
great range like for example 4.2 to 6 mm. The laser consistently
generates an opening of the desired diameter and shape which is
difficult to reproduce manually. An experienced surgeon can be very
good in making the openings but sometimes the shape may be
eccentric or oval. When implanting Pi in eye the more circular,
central and precise the opening the better it is. For Restor and Tecnis
the openings are usually a tad smaller than for Crystalens. With the
Crystalens symmetrical opening is important. Otherwise chances of
torque in the lens known as z syndrome may develop. If the bag were

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