Types and benefits of Retina Laser

According to the type of retinal disorder, laser therapy is provided in different ways.

Proliferative Diabetic Retinopathy (PDR)

• Proliferative diabetic retinopathy is a form of advanced or end-stage diabetic retinopathy. Due to the long duration of diabetes and uncontrolled blood sugar levels, the retinal blood vessels undergo changes which happen in stages, ultimately leading to PDR. PDR is a vision-threatening disorder. When timely treatment is not provided, it can cause complications like bleeding within the eyes from the abnormal vessels and/or can retinal detachment. 
• Retinal laser therapy is helpful in PDR as it decreases the risk of such complications. The doctor performs pan-retinal photocoagulation (PRP) to treat PDR.
• The retina is a 360-degree structure that is responsible for vision. The central retina is called as macula and is the chief zone responsible for fine vision. During proliferative diabetic retinopathy, the doctor applies laser therapy to the poorly vascular retinal areas sparing the macula.  Proliferative diabetic retinopathy therapy is provided in three to four sessions since the almost 360-degree retina is slowly covered with laser spots. The formation of abnormal blood vessels and undue complications are prevented by this procedure. 

Diabetic Macular Edema (DME)

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.

Retinal Vein Occlusion (RVO)

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 Degeneration

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.

Central Serous Chorioretinopathy (CSC) and Choroidal Neovascularization

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.

Patient preparation

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. 

After the procedure

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 a decrease in contrast sensitivity and colour vision.

Types and method

There are two methods by which laser therapy can be performed: Contact and Non-Contact methods. 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 handheld instrument.

Conclusion

Retinal laser photocoagulation is a relatively safe, fast and a painless procedure.

Written by: Dr. Dheepak Sundar – Consultant Ophthalmologist, Velachery