is a highly concentrated light that is beamed onto the retina to treat
the desired area. It is a painless Out Patient procedure, lasting about
10-30 minutes that does not require admission. It may require more than
one sitting to complete the treatment. In majority of cases, the aim of
laser treatment is to try to prevent further loss of vision. It can not
regain the vision already lost due to retinal disease. After the laser
treatment, the patient may require to undergo repeat Fluorescein
Angiography at a later date to monitor the response, and may require
more laser if indicated.
Lasers are commonly used in the following conditions:
the damaged small vessels of the retina
leak fluid and blood, causing swelling of the retina. These changes
decrease vision if the central part is affected. Laser is done to seal
these leaks. However laser is done to prevent or retard further loss of
vision and not to improve vision. In severe changes when new blood
vessels have grown (Proliferative Diabetic Retinopathy), multiple
sittings of laser are needed to regress these vessels. This is called
Pan Retinal Photocoagulation and is highly effective in preventing
severe visual loss due to recurrent bleeding in vitreous.
Retinal tears and holes-
In a retinal tear or a hole without a
retinal detachment, laser is done prophylactically to seal the hole and
prevent or limit the detachment.
Age Related Macular Degeneration-
In patients with wet type of
AMD not involving the central part, laser can be done to close the
Choroidal Neovascular Membrane. This can prevent severe visual loss.
However in patients with central involvement, other specific lasers are
used like- Photo Dynamic Therapy (PDT) with verteporfin and
Transpupillary Thermo Therapy (TTT) with Diode laser.
Other Retinal vascular disorders-
like retinal vein occlusions
and Eales disease also require laser at times. In venous occlusions, the
central retina may swell up due to fluid collection leading to reduced
vision. Such cases require laser to decrease the swelling, which may
help in improving the vision. Venous occlusions may also lead to new
vessel formation, which needs laser to regress these vessels. Similarly
in Eales disease, laser is required to reduce recurrent vitreous
hemorrhages. Laser is also useful in selected cases with Central Serous