Scatter Laser Treatment (Panretinal Photocoagulation)

Medically Reviewed By William C. Lloyd III, MD, FACS

What is scatter laser treatment?

Scatter laser treatment, also known as panretinal photocoagulation, is an outpatient procedure that treats proliferative diabetic retinopathy. This condition damages the tiny blood vessels of the retina and threatens vision. The retina is a thin membrane in the back of the eye that senses light. It captures images from the eye lens and sends them along the optic nerve to the brain. Scatter laser treatment can preserve the health of the retina and prevent vision loss. 

Uncontrolled diabetes and long-term high blood sugar levels lead to proliferative diabetic retinopathy. The damaged blood vessels are fragile and can leak and bleed. This causes the macula (the center of the retina) to swell. This is macular edema, which causes blurred vision, severe vision loss, and blindness. 

Scatter laser treatment is only one method used to treat proliferative diabetic retinopathy and prevent macular edema. Discuss all of your treatment options with your doctor to understand which option is right for you. 

Other procedures that may be performed

Your doctor may perform another laser treatment, called retinal laser therapy, if you have macular edema. Retinal laser therapy seals off bleeding blood vessels and can prevent serious vision loss. This is usually done several weeks before scatter laser treatment. 

Why is scatter laser treatment performed?

Your doctor may recommend scatter laser treatment to treat and prevent damage to blood vessels of the retina due to advanced diabetic retinopathy. This is called proliferative diabetic retinopathy. It is an eye disease from uncontrolled diabetes and long-term high blood sugar levels. Generally, doctors use scatter laser treatment when damage is severe and some vision loss has occurred. It will not restore vision but it can prevent further loss.

In proliferative diabetic retinopathy, the retina creates new blood vessels because the original diabetic vessels no longer supply adequate fresh blood. These new vessels are abnormally fragile and leak easily, causing the macula (the center of the retina) to swell. This is called macular edema. Macular edema can lead to blurred vision, severe vision loss, and permanent vision loss and blindness. Scatter laser treatment can help prevent macular edema and severe vision loss.

Who performs scatter laser treatment?

Ophthalmologists perform scatter laser treatment. An ophthalmologist is a doctor with specialized training in diseases, conditions and surgery of the eye.

How is scatter laser treatment performed?

Your scatter laser treatment will be performed in an office or outpatient clinic. The procedure generally includes these steps:

  1. Your doctor will examine your eyes and check your vision before the procedure.

  2. Your doctor may numb the surface of your eye with drops.

  3. You may have a mild oral sedative before the procedure to help you relax, if needed.

  4. Your doctor will place a special lens on the clear cornea that will help focus the laser energy on the affected retina.

  5. Your doctor will aim the laser to treat the diseased areas of the retina. The laser destroys the damaged retina and the abnormal vessels disappear. It also slows the growth of new abnormal vessels.

  6. You will need to return for more treatments. The number of treatments varies depending on your condition.

Will I feel pain?

Your comfort and relaxation are important to you and your care team. Scatter laser treatment generally causes little to no discomfort. Your doctor may numb your eye with anesthetic drops to help you stay comfortable. You may also have a mild sedative to help you relax. Tell your doctor if you are uncomfortable in any way. 

What are the risks and potential complications of scatter laser treatment?

Scatter laser treatment involves risks and potential complications. Complications may become serious in some cases. Complications can develop during the procedure or your recovery. Risks and potential complications of scatter laser treatment include: 

  • Adverse reaction or problems related to sedation or medications, such as an allergic reaction and problems with breathing

  • Blurred vision or decreased vision, which may be temporary or permanent

  • Decrease in night vision

  • Recurrence of proliferative diabetic retinopathy

Reducing your risk of complications

You can reduce the risk of certain complications by following your treatment plan and:

  • Following activity, dietary and lifestyle restrictions and recommendations before your procedure and during recovery.

  • Keeping all scheduled appointments

  • Notifying your doctor immediately of any concerns, such as eye pain, change in vision, or worsening vision

  • Taking your medications and eye drops exactly as directed

  • Telling all members of your care team if you have any allergies

How do I prepare for scatter laser treatment?

You are an important member of your own healthcare team. The steps you take before your procedure can improve your comfort and outcome. You can prepare for scatter laser treatment by:

  • Answering all questions about your medical history, allergies, and medications. This includes prescriptions, over-the-counter drugs, herbal treatments, and vitamins. It is a good idea to carry a current list of your medical conditions, medications, and allergies at all times.

  • Arranging for someone to drive you home after the procedure

  • Getting testing as directed. Testing will include a thorough eye exam and other tests as needed.

  • Not wearing contact lenses, eye makeup, and face lotions exactly as directed on the day of your procedure

  • Taking or stopping medications exactly as directed

Questions to ask your doctor

Preparing for scatter laser treatment can be stressful. It is common for patients to forget some of their questions during a doctor’s office visit. You may also think of other questions after your appointment. Contact your doctor with concerns and questions before your procedure and between appointments. 

It is also a good idea to bring a list of questions to your appointments. Questions can include:

  • Why do I need scatter laser treatment? What are the other options for treating my retinal disease?

  • Why am I a good candidate for scatter laser treatment?

  • Do I also need conventional retinal surgery? When will I have it?

  • What are the chances that scatter laser treatment will improve my retinopathy?

  • How long will the procedure take? When can I go home?

  • What kind of assistance will I need at home?

  • What restrictions will I have after the procedure? When can I return to work and other activities?

  • How should I take my medications?

  • How will you treat my pain?

  • When should I follow up with you?

  • How should I contact you? Ask for numbers to call during and after regular hours.

What can I expect after scatter laser treatment?

Knowing what to expect after scatter laser treatment can help you get back to your everyday life as soon as possible. 

How will I feel after scatter laser treatment?

Scatter laser treatment generally causes little discomfort, but your doctor will treat it as needed. Tell your doctor if you have pain because it can be a sign of a complication.

You will likely go back to normal activities within a few days. You will need to avoid vigorous activity for two weeks or longer as your eye heals. Tell your doctor about all your activities and follow any instructions for returning to them.

You will not regain lost vision after scatter laser treatment. Your vision may get worse but should improve to its previous level in two to three weeks. Sometimes vision loss is permanent. This procedure may cause some peripheral vision loss in order to save as much of the central vision as possible. Talk to your doctor about your risks and treatment goals. 

Scatter laser treatment will not prevent further retinal damage from diabetic retinopathy. You will need regular eye exams and good blood sugar control to keep your eyes healthy. 

When can I go home? 

You will go home on the same day of scatter laser treatment. You will need a ride home from the doctor’s office or clinic because your vision may be blurry. Do not drive until your vision has cleared. 

When should I call my doctor? 

It is important to keep your follow-up appointments after scatter laser treatment. Contact your doctor for questions or concerns between appointments. Call your doctor right away or seek immediate medical care if you have: 

Was this helpful?
  1. Facts about Diabetic Retinopathy. National Eye Institute.
  2. Laser Treatment of Diabetic Retinopathy. Joslin Diabetes Center.
  3. Pan-Retinal Photocoagulation.
  4. Pan-Retinal Photocoagulation (PRP). Pabalan Eye Center.
  5. Photocoagulation. Makati Medical Center.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Aug 21
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