الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The word laser is a cronym of (light Amplification
by Stimulated Emission of Radiation). The laser
beam is a highly coherent beam and relatively monochromatic
and can be focused in small area.
The common laser used in opthalmology are Argon
and Krypton (red and yellow), Dye, C0 2 , frequency double
neodymium YAG and YAG are more recent lasers and are in
use but not common as the previous two. Ruby laser is
the oldest one and nearly not in use while excimer
laser is the most recent laser now known and it is
mostly used exper~nentally.
Laser can be used in the treatJJ.ent of the anterior
segment disorders as in glaucoma, some iris disorders,
pupil disorders, in some lens condition and recently
even tried in treatment of pterygium and even more recently
excimer laser is tried in corneal surgery.
In Glaucoma, there are many procedures used for
the treatment of glaucoma as:
Trabeculoplasty: In which the laser shots are
applied in the anterior part of the trabecular meshwork.
This will result in shrinkae;e of the collagenous component
of the trabecular meshwork, decreasing its diameter and- 109 -
increase the \Vidth of the intertrabecular spaceses and
result in improvement in aqueous outflow. 100 laser
burns are applied to )60 degrees or 50 burns to 180
degrees of trabecularmeshwork.
Goniophotocoagulation: Laser photocoagulation of
neovascular vessels where they cross the scleral spur
in cases of neovascular glaucoma with open angle.
Trabeculostomy: used to control the neovascular
glaucoma. In this procedure the trabecular meshwork
tissue is vaporised by C0 2 laser until the anterior
chamber is perforated.
Gonioplasty: coagulation of the iris root to
contract the iris away from the angle and trabecular
meshwork.
Pupilloplasty: used to contract the sphincter
in a small area, peak the pupil and establish a connection
between the posterior and anterior chamber.
Photocoagulation of the ciliary process by the
argon or Nd - YAG laser for the treatment of aphakic
malignant glaucoma.- no -
Cyclocoagulation: 32 laser burns of Ruby laser
are applied circurnferentially 3.5 mm from the limbus to
decrease the production of aqueous humor.
In iris disorders: laser can be used to treat
different types of iris cyst as iris cyst in the anterior
surface, pigment epithelial cyst and dislodges
pigmented iris cyst in the anterior chamber.
In pupil disorders: laser photomydriasis: used
to minimize the miotic effect of the antiglaucoma medication
and to allow aqueous fluid to move from the
posterior to the anterior chamber and thereby break an
attack of pupillary block glaucoma.
Laser coreoplasty: to correct the displacement of
the pupil away from the visual axis. This by laser
application in a radial direction from the pupilary
margin or in the area just il1J3id the outer limit of the
iris collerate.
In lens disorders: By the Nd- YAG laser can open
opaque posterior capsule after extracapsular cataract
extraction in aphakic or psudophakic eye. YAG laser
anterior capsulotorny one day before extracapsular cataract
extraction operation make the procedure of the
operation more easier.- 111--
In pterygium: after extraction of the pterygium,
laser photocoagulation of the blood vessels in this area
Vlill prevent recurrence of the pterygium.