Retinal laser photocoagulation is a modality of treatment used by ophthalmologists to treat various disorders related to retina. The list of disorders includes diabetic retinopathy, retinal vein occlusion, retinal breaks, central serous chorioretinopathy and choroidal neovascularization. Unlike patients’ beliefs, the procedure is not like a surgery. The doctor during this therapy ensures that the laser beam (focussed light waves) falls on the desired site in the retina. During this process heat energy is produced and retinal coagulation is achieved and thereby the intended treatment is provided.
According to the type of retinal disorder, laser therapy is provided in different ways.
DME is abnormal fluid collection leading to swelling at the level of the macula causing vision loss. Retinal laser photocoagulation is beneficial in some cases of DME. Here, minimal laser spots are given targeting the leaky macular blood vessels to reduce the swelling.
In RVO, the entire retinal vessel or a part of the retinal vessel gets blocked due to various reasons leading to abnormal blood flow to the part of the retina supplied by the vessel. Here, Retinal laser therapy is useful, similar to PRP in PDR as explained before.
Retinal tears, holes and lattice degenerations (areas of retinal thinning) occur in almost 10% of the normal population and are more common among myopes. If not treated there is always a risk of developing retinal detachment through the breaks. The doctor in such cases can delimit the retinal breaks with two to three rows of laser spots around the breaks thus causing dense adhesion in the surrounding retina and thereby decreasing the risk of retinal detachment. It is mandatory to screen and laser such lesions prior to LASIK and cataract surgeries.
Both the conditions lead to areas of leak at the macular level causing fluid collection and vision loss. Based on the specialist’s decision, in some cases retinal laser therapy targeting the leaky areas is beneficial.
The laser procedure is performed only after providing topical anaesthesia. Eye drops would be used prior to the procedure to minimize pain. The procedure is relatively painless. The patient might feel a mild pricking sensation during the therapy. The entire procedure might take place for five to twenty minutes depending on the patient’s disease.
The patient might feel mild glare and visual discomfort for a day or two. He or She will be advised to use antibiotic and lubricant eye drops for 3 to 5 days depending on the type and duration of the procedure. Extensive PRP in diabetic retinopathy can lead to decrease in contrast sensitivity and colour vision.
There are two methods by which laser therapy can be performed: Contact and Non-Contact method. In the contact procedure, a lens with a lubricating gel will be placed over the patient’s eyes and laser therapy would be delivered in sitting position. In the non-contact method, the patient is made to lie down and laser therapy is delivered. Sometimes the doctor might apply minimal pressure around the patient’s eyes with a hand held instrument.
Retinal laser photocoagulation is a relatively safe, fast and a painless procedure.
Written by: Dr. Dheepak Sundar – Consultant Ophthalmologist, Velachery