Panretinal Photocoagulation Laser (PRP)

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What is panretinal photocoagulation (PRP) laser?

PRP is a type of laser treatment used in patients who develop new, abnormal blood vessels in the retina or drainage system of the eye.  This treatment is commonly administered to patients with proliferative diabetic retinopathy, ischemic retinal vein occlusions, or neovascular glaucoma, to preserve the vision and reduce risk of blindness.

New blood vessels growing along the optic nerve and surface of the retina can cause retinal detachment and vitreous hemorrhage

Why do I need PRP laser?

PRP laser treatment targets the outer retina, prevent new abnormal blood vessels (neovascularization) from growing, and encourages existing ones to shrink and dry up. Abnormal blood vessel formation is often seen in patients with longstanding poorly controlled diabetes mellitus and other ischemic retinal diseases.  These vessels grow in abnormal locations and are weaker than normal blood vessels. They can and leak, resulting in floaters and blurry vision from blood collecting in the vitreous gel of the eye (vitreous hemorrhage).  The abnormal blood vessels can also pull on the retina (traction) and lead to retinal detachment. Abnormal blood vessels can sometimes grow in the drainage angle of the eye and this can lead to neovascular glaucoma, a very painful condition that needs to be treated promptly.


Panretinal photocoagulation laser is applied to the peripheral retina to stabilize proliferative retinopathy

Where is PRP performed?

PRP laser is usually performed in the outpatient department at the hospital or at an ophthalmology office.  It is typically done at a slit lamp microscope or sometimes the doctor will use a headset.  In some cases it may be performed in the operating room with a retinal surgery.  PRP laser is not offered by all ophthalmologists in all regions.

How is PRP done?

Your eyes will typically be dilated in advance of the treatment.  A special laser is used to treat the affected areas and often done over multiple sessions.  Each session typically lasts 15-30 minutes.  Patients usually feel a pinching/aching sensation as each laser treatment or “burn” is applied but the treatment is usually tolerable. 

The entire peripheral retina is treated with PRP laser, reducing the drive for neovascular membranes

Are there any risks with PRP?

PRP laser  is generally a safe procedure with few risks.  There can be some pain during the procedure.  The most common risks are retinal bleeding, macular edema, and defects in the outer field of vision.  Rare risks include serous retinal detachment. Symptoms of retinal detachment are flashes, lots of new floaters or a dark shadow covering the peripheral vision (curtain defect).  If you experience these symptoms seek emergency care immediately. There is also a rare chance of peripheral vision loss that may affect your ability to drive long term or unintended burn to the centre of the retina that can reduce your vision. Night vision and colour vision can also be affected.

What should I expect after PRP treatment?

You may notice a mild dull ache in the eye(s) or headache after treatment. The vision will be “dazzled” and/or may seem darker after the treatment.  This effect may last 24 hours. Depending on the amount of PRP laser required there may be some loss of peripheral vision and colour contrast.  You can resume normal activities after the laser is completed. Your peripheral vision needs to be monitored after laser to ensure you continue to meet driving standards.

Cataract surgery wait times

Wait times for cataract surgery are updated quarterly, with wait 1 representing how long it takes to get in to see the surgeon in the office, and wait 2, how long it takes after that to get in for surgery.
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