Call Us: 703.273.2398

Tag Archives: laser treatment

Laser Treatment for Diabetic Macular Edema

Laser photocoagulation is still the best treatment for diabetic macular edema.  Diabetic macular edema, or DME, is the most common complication of diabetic retinopathy and it will affect almost everyone with the eye disease.

DME is also known as CSME (clinically significant macular edema).  The two terms are exactly the same for our purposes.

Before Laser Treatment

Diabetic macular edema before laser treatment.
Click to Enlarge

This is a retinal photograph of a patient with diabetic macular edema.  The white spots and flecks are evidence of chronic swelling of the retina from diabetes.  The swelling involves the macula, the most sensitive portion of the retina and causes loss of vision.

The goal of any treatment, laser, steroid injections or anti-VEGF injections is to reduce the swelling.  If the swelling improves, it is highly likely the vision improves, too.

Usually, a fluorescein angiogram is performed to demonstrate where the normal retinal blood vessels are leaking.  Using the energy of the laser, the areas of leakage are heated and this usually, but not always leads to improvement of the swelling.

Treatment can involve anywhere from a few to dozens of burns…all depending upon the number leaks.

Laser treatment to the center of the macula could lead to a permanent blind spot in the vision and, therefore, is not always the best treatment for every patient.  In these types of cases, intraocular injections of anti-VEGF or steroids might be a smarter option.

Laser Treatment Reduces Macular Edema

This is the same retina several months after laser treatment.  Note the white spots have all disappeared.

Diabetic macular edema after laser treatment.
Click to Enlarge

After 4-6 months, I can usually tell if the laser treatment is effective or needs to be augmented (ie. repeated).  At times, I’ll know I’ll need to treat with a combination of laser and intraocular injections of Avastin, steroids or even Ozurdex.

The laser treatment for diabetic macular edema is very similar to weeding a garden.  It is not a cure, and will have to be repeated.

What Does This Mean?

There are a variety of treatments for diabetic macular edema.   Laser treatment is still the standard of care for treating this common condition seen with diabetic retinopathy.

Though we have a variety of effective treatments available, we still don’t have a cure.  The best advice remains regular examination and treatment as early as indicated.

Randall V. Wong, M.D. 
Ophthalmologist, Retina Specialist
Fairfax, Virginia

Diabetic Macular Edema: Have No Fear

Diabetic Macular Edema,




Diabetic macular edema (DME) is swelling in the retina caused by diabetic retinopathy.  More specifically, the swelling is located in the macula, the functional center of the retina.

Diabetic Macular Edema Occurs In Almost Everyone

DME is the most common “side effect” or complication of diabetic retinopathy.  It should not be feared, but rather, it should be expected.  Almost every diabetic patient will develop some degree of macular swelling in their lifetime.

Diabetes can be considered a disease of blood vessels, caused in some way by high sugar levels.  For reasons that are not completely known, the blood vessels in the retina start to leak, both blood and the fluid component of blood.

As the leakage nears the macula, we get concerned as swelling in the macula leads to loss of vision.  The idea of treatment is to prevent the fluid from ever reaching the macula.  If fluid has already developed, treatment may prevent further leakage (and thus preserve vision) or possibly decrease the swelling (and maybe improve vision).

Laser Treatment is Only Approved Treatment

The only FDA approved treatment for diabetic macular edema, aka clinically significant macular edema (CSME), is laser treatment.  The laser is used to burn those areas around the macula that are leaking.  Often, the laser results in stablizing the retina and preventing further leakage.

Laser is Painless

The laser does not hurt.  There are no nerve endings underneath this portion of the retina.  The treatment may last just a few minutes and is accomplished while you are sitting at the laser.  In fact, the visit should mimic a routine dilated exam.

After treatment, no “healing” is really needed.  I personally do not recommend any drops, patches or time off from work.  Your doctor’s recommendations may vary.

Laser treatment for diabetic macular edema takes several months to start working.  After 4-6 months, I can usually tell if more treatment will be needed.

What Does This Mean?

Laser treatment for diabetic macular edema is the gold standard.  While DME is quite common, the treatment works best if instituted early in the disease process, preferably while the vision is 20/20.

Not all patients can be treated with laser.  Other treatments for DME include  intraocular injections of Avastin or Kenalog.  Using any of these tools, almost everyone with diabetic retinopathy may be treated.

Regardless, fear not, the treatment for the disease is quite successful in preventing further vision loss.  It is painless, safe and effective.

Enhanced by Zemanta

Retinal Ischemia: Supply vs. Demand

Retinal ischemia causes VEGF to be liberated inside the eye.  In cases of diabetes this can lead to diabetic retinal detachment or neovascular glaucoma.  Treatments included pan-retinal photocoagulation (laser) or anit-VEGF medication such as Lucentis or Avastin.

Ischemia results when oxygen supply does not meet oxygen demand to any tissue.  Other examples  are the heart and legs.  With strenuous activity, O2 demand increases.  If the body can’t compensate, chest pain or leg pain develops.

In cases of proliferative diabetic retinopathy, the retina becomes ischemic due to the loss of the microcirculation of the eye.  The small capillary beds that help feed the retina often get blocked and close off.  Blood flow is reduced, and therefore, so are oxygen levels.

In response to this lack of blood, or oxygen, supply, the ischemic retina produces Vascular Endothelial Growth Factor (VEGF).  VEGF causes abnormal blood vessels to grow on the surface of the retina and other structures inside the eye.  This can lead to blindness by causing a diabetic retinal detachment or glaucoma.

Stop the Ischemia

If we were to stop the ischemia, the VEGF production would cease. If we can change conditions so that supply is equal to demand, the imbalance is gone.

But we don’t know how to improve oxygen supply to the retina.  Presently, laser treatment and anti-VEGF medications are employed.

Laser Treatment Reduces Demand

As we are unable to increase oxygen supply, laser photocoagulation (specifically, pan-retinal photocoagulatoin, aka PRP) is used to decrease demand.  By ablating, a fancy term for killing, retinal tissue, we are in effect, reducing the demand.

If enough laser is performed, the overall O2 requirements will decrease.  Ischemia is stopped and VEGF is no longer produced.

The eye becomes stable.  A diabetic retinal detachment and glaucoma are prevented.

anti-VEGF Medications Block VEGF

Anti-VEGF medications such as Lucentis and Avastin block VEGF from doing its job.  In doing so, neovascularization can not be initiated and diabetic retinal detachment and glaucoma are avoided.

Is the eye stable?

What Does This Mean? Actually I am not sure.  The end result of laser (PRP) and anti-VEGF treatments are the same; preventing retinal detachment and glaucoma.

The use of laser for proliferative diabetic retinopathy is old hat.  It has been saving the sight of diabetics for about 40 years.  It is a good treatment because it fixes the problem.  PRP, when properly performed, stabilizes the eye by eliminating the ischemia.  It secondarily stops VEGF by halting the initial O2 imbalance.

I am not sure; however, if intraocular injections of Lucentis/Avastin actually fix the problem.  There is no mechanism to fix the ischemia.  VEGF is still liberated as the ischemia still exists.  Therefore, careful monitoring and repeated injections are needed.

Reblog this post [with Zemanta]

Lasers for "Eye Surgery"

There are many lasers and many ways to use lasers in eye surgery.  I am asked all the time if I perform “laser surgery,” but I know what they are asking.  While I do perform laser surgery for diabetic retinopathy, and (not so much anymore) macular degeneration, they are really asking if I perform laser vision correction eye surgery.  No, I don’t.

There are at least 5 different areas of ophthalmology using at least 6 different laser to perform “laser surgery.”

Laser Vision Correction is a laser procedure using an Excimer laser.  Principally, it reshapes the cornea to refocus light, allowing less dependence upon glasses.  Okay, it reshapes the cornea so people are less near-sighted.  Most of the time contact lenses and glasses are no longer needed.  People see well, assuming the retina/macula is normal.  There is limited use for far-sighted individuals.

Glaucoma laser surgery is performed for two reasons, and uses two different lasers.  In several types of glaucoma (e.g. open angle glaucoma, pigment dispersion), laser burns, using an argon laser, are placed on the trabecular meshwork to cause a reduction in eye pressure.  The trabecular meshwork is part of the drainage portion of the eye.  A diode laser can be used to perform a similar procedure as well.

In angle closure, or narrow angle, glaucoma, a ND:Yag laser is utilized to “cut” a hole in the iris (see below).  This hole, aka iridectomy, creates an alterate pathway for the intraocular fluid to leave the eye.

A similar Yag laser can be used for another glaucoma procedure called cyclophotocoagulation which reduces eye pressure by destroying the ciliary body, the tissue that makes intraocular fluid.

Nd:Yag laser is also used to fix “after-cataracts.”  When the natural cataract is removed from the eye, it is replaced by a crystal clear implant.  The implant rests in a clear sac that used to hold the cataract.  This tissue is similar to “Saran” wrap and commonly gets cloudy.  This cloudy tissue causes decreased vision in much the same way the original cataract caused problems.  Using the Nd:Yag laser, a cutting laser, a small hole is cut in this tissue allowing vision to be restored.

Diabetic retinopathy is common treated with laser photocoagulation.  Most of the time an argon laser is used for either treating macular edema or proliferative diabetic retinopathy.  An argon laser transfers heat and is a type of thermal laser treatment.  Laser treatment for diabetic macular edema is directed at microaneurysms.  Theoretically, the heat from the laser causes these tiny outpouchings along the vessel walls to scar over and stop leaking.  The same laser is used to perform panretinal photocoagulation (PRP) for cases of proliferative diabetic retinopathy.

Photodynamic Therapy (PDT) is a type of treatment for wet macular degeneration.  It was introduced as a “cold” laser.  A drug, Verteporfin,  is infused into the body via an intravenous line.  The drug accumulates in the abnormal blood vessels gathered underneath the retina.  The PDT laser is then used to convert the accumulated Verteporfin into a substance toxic to the neovascular tissue.  This treatment is still used for wet macular degeneration.

CO2 and Erbium lasers are also used in cosmetic skin laser surgery and is included here as our oculoplastic colleagues use these in their practice.

What Does This Mean? It’s not a coincidence that there are so many lasers used in ophthalmology.    Lasers (Light Amplification by Stimulated Emission of Radiation) are basically light beams.  As the structures of the eye are directly visible, i.e. you can see them, and can be “reached” by light, or laser.  Unlike other fields of medicine, we enjoy direct visualization of the structures/tissues we are treating.

So,  “Do I perform laser eye surgery?  Yes, I do.”


Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

Eye Injections Challenge Eye Laser for Diabetic Retinopathy

There is a small study just published in the journal “Ophthalmology” stating that intraocular injections of Lucentis® were superior to laser photocoagulation for the treatment of diabetic macular edema.  As you read this, don’t forget that the “gold-standard” for treatment of diabetic macular edema is still laser photocoagulation.  These “studies” are very small and not of the caliber needed to change the way we practice, but there is still some merit to the findings.

In this study, 126 patients with diabetic macular edema were split into 3 groups;

  1. treated with Lucentis® only
  2. treated with laser only
  3. treated with laser, then Lucentis

Of the 3 groups, the patients receiving Lucentis®, when compared to the laser only group, had the most improved vision and reduced “thickness” or “swelling” of the macula.  The 3rd group, where laser and Lucentis® were combined, was not significantly better in terms of vision, but the swelling was improved more than laser only.

What Does This Mean? The study indicates that intraocular injections of anti-VEGF therapy are better than laser treatment for diabetic macular edema.  If you watch the internet, many “authorities” will start proclaiming that this is a new, and better, treatment for diabetic macular edema.  But we should be cautious.

First, the best studies require that the “studies” are prospective, randomized and double-blinded.  These studies are prospective (vs. retrospective), randomized to treatments options, and basically, no one knows what treatment is administered, including the doctors and patients.  This helps remove bias and placebo effects.  This also means, in a study like this, “fake” lasers would have been performed along with “sham” injections.  After the study, a code would be cracked to disclose which treatments were given to which patients.

Second, the study is too small and too short to have allow any significant meaning.  “Statistical significance” means that an adequate number of patients were studied such that the results could not have occurred by chance.  I don’t know the actual number of patients needed, but most likely would have involved hundreds instead of tens and would have involved more than one testing center.

We also don’t know if the effects are long-lasting.  We only know there was improvement  in the short period of the study.  Now if the effects are still noted 1-2 years after treatment, for example, then maybe we are on to something.

Last, many aspects of the patient selection and treatment are not standardized.  For example, we don’t know if the patient selection was biased in any way that might favor one treatment over another.  For example, perhaps everyone in one group had better sugar control than the other.

My point is, that studies such as this are suspect due to many shortcomings.  Proper prospective, randomized, double-blinded studies take years to develop, perform and analyze.  The AREDS1 Study is an example.  These studies also take large reserves of cash.

The value of these studies is; however, that if similar “small” studies have similar themes, then these may serve as a nidus to create and form much larger, more formidable studies.  Also, for the clinicians (aka yours truly), it also gives us information about alternative treatments that seem viable.


Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

Reblog this post [with Zemanta]

Retina Laser Treatment Saves Vision

There are two conditions where laser treatment is needed in patients with diabetic retinopathy:  macular edema and evidence of proliferative retinopathy.  In cases where macular edema, swelling of the retina in the macular area, is present, “focal” photocoagulation is needed.  In cases of proliferative diabetic retinopathy, “pan-retinal photocoagulation,” or PRP, is needed.

  • Focal Laser —> Diabetic Macular Edema
  • PRP  —> Proliferative Diabetic Retinopathy

Focal Laser and Diabetic Macular Edema

If you remember, this is the most common stage of diabetic retinopathy.  Almost every patient with diabetic retinopathy develops some leakage in the macula, potentially causing decreased vision.  The normal retinal blood vessels develop tiny little blebs along the blood vessel walls.  Theses outpouchings are called “microaneurysms.”  We know, and can prove, using fluorescein angiography, that these microaneurysms leak both blood and the clear, fluid part of blood.  “Focal” laser is presently the treatment of choice for diabetic macular edema.

"Focal" Laser Treatment to Treat Microaneurysms
"Focal" Laser Treatment to Treat Microaneurysms

A small lens is placed on the surface of the eye.  The laser does not hurt, is performed in the office and takes less than 10-15 minutes.  The idea is to treat the microaneurysms near the macula, but not the actual macula.  Treating the actual macula will cause permanent blind spots in your vision (not good).

It may take several months to determine if the laser was successful.  There is no care needed after the laser is performed.  It will most likely need to be repeated some day.

Treating the leaky microaneurysms is like weeding a garden, new areas will crop up.

Pan-Retinal Photocoagulation (PRP) is Used to Treat Proliferative Diabetic Retinopathy

Proliferative diabetic retinopathy, or PDR, affects about 10%  of patients with diabetic retinopathy and can lead to blindness.  Proliferative diabetic retinopathy develops when the retina becomes ischemic.  When a tissue is “ischemic,” it is not getting enough oxygen, usually from poor, or insufficient, blood flow.

Ischemia = Oxygen Demand Exceeds Supply

When the retina becomes ischemic, it releases a protein called Vascular Endothelial Growth Factor (VEGF).  The vascular endothelial growth factor (VEGF) causes abnormal blood vessels (neovascularization) to develop on the surface of the retina and on other parts of the inside of the eye such as the optic nerve and iris.

Blindness may develop from massive proliferation of the neovascularization (aka abnormal blood vessels) causing either retinal detachment or, a rare type of painful glaucoma (neovascular glaucoma – NOT the regular glaucoma).

Neovascularization, aka "Abnormal Blood Vessels"
Neovascularization, aka "Abnormal Blood Vessels"

In the illustration above, neovascularization has developed on the surface of the retina.  These abnormal blood vessels have also broken and bled causing a very small vitreous hemorrhage.  This blood may be seen as sudden floaters, or if large enough, may block most of the light from hitting the retina, causing significant loss of vision.

Remember the word ischemia? (Oxygen demand exceeds oxygen supply).

So far, ischemia has caused vascular endothelial growth factor (VEGF) to be liberated.  The VEGF has caused neovascularization to develop.

Stop the ischemia, Stop VEGF,  Stop the Proliferation

If we laser the peripheral retina, the portion of the retina away from the macula, we can stop the production of VEGF in most cases and arrest the proliferative phase of the diabetic retinopathy.

In effect, we are killing small portions of the peripheral retina with each laser pulse. Since we (scientists and other smart guys) are unable to increase oxygen supply, we must decrease demand.  The “ischemia” is over, VEGF production stops and the neovascularization goes away.  Disease process halted!

Pan Retinal Photocoagulation (PRP) Used to Treat Proliferative Diabetic Retinopathy
Pan Retinal Photocoagulation (PRP) Used to Treat Proliferative Diabetic Retinopathy

This procedure is also performed in the office.  It can be uncomfortable (actually it can hurt!) and I prefer to numb up the entire eye.  The procedure can take 30-45 minutes.  It make take several weeks to determine if enough laser is performed.  It is not uncommon for 1000 pulses or more to be required.

If performed timely, this potentially blinding phase of the disease can be halted!

Thanks for reading.


Enhanced by Zemanta

Laser Treatment Still The Best

Laser treatment for diabetic macular edema is still the preferred treatment for most patients with diabetic retinopathy.  Despite all the recent news about intraocular injections of anti-VEGF and steroid medications, the laser remains the mainstay.

The most common manifestation of diabetic retinopathy is the development of macular edema (also known as diabetic macular edema (DME) or clinically significant macular edema (CSME)).  Almost all patients who develop diabetic retinopathy develop some degree of swelling in the macula.  The normal retinal blood vessels begin to leak into the surrounding tissue.  It is not unlike a “soaker” hose for your lawn.  Of all the stages of diabetic retinopathy, this is the most common and does NOT lead to blindness.

The development of swelling, or edema, can decrease the central vision.  This is the most common way vision is lost.  The surgical goal is to arrest further swelling by treating the retina with laser photocoagulation.  The laser treatment is focused on areas of leakage called “microaneurysms” which are the actual incompetent areas in the normal retinal vessels.

Once treated, the macular swelling usually stays the same.  About 80% of the time, the macular edema, and vision stabilize!  My job is achieve status quo.  At times, especially when caught early, the vision improves as the swelling decreases.  Rarely, the laser doesn’t work.

Intraocular injections of Avastin® for macular edema or intraocular Kenalog® can be used for cases in which laser doesn’t work.  In the future, Ozurdex® or other intraocular sustained release delivery systems may be useful.

The laser used is usually a “hot” laser, that is, it works by transferring heat to the tissue.  The procedure is performed in the office setting, takes no longer than a regular office visit and is painless.  There is no post-operative care needed.

The result of the laser can take months to assess.  I usually will not see a patient back for another 4 monthas or so.


Randall V. Wong, M.D.

Ophthalmologist, Retina Specialist
Fairfax, Virginia

Reblog this post [with Zemanta]

Laser Treatment for Diabetic Retinopathy Still The Best: True Cases

I saw two patients (RJ and JR)  yesterday that have the same “problem.”  They both are patients with diabetes and both have advanced, or proliferative, diabetic retinopathy.  Both have had diabetes for over 20 years, are on insulin and have been treated with pan-retinal photocoagulation to control the proliferative diabetic retinopathy.  Both still have 20/20 vision.  Neither have ever required retinal surgery and probably never will.  Their visual prognosis is excellent.

My Comments

This is not uncommon.  My point in writing about them is that there are many, many patients with diabetic retinopathy, even the potentially blinding stage, that see well, even normally.  I have taken care of them for several years and they have been stable since receiving pan-retinal photocoagulation  (PRP).  Future visits with me are limited to looking for signs of recurrence.   PRP is not a cure, but it has been the mainstay of treatment since the 1970’s.

What is Pan-Retinal Photocoagulation? Also known as PRP, panretinal photocoagulation is a procedure whereby the “peripheral” retina, or side-retina, is treated with multiple laser burns.  The burns are tiny.  Usually 1200-1500 burns are necessary for a successful treatment.  It does not directly effect vision.

How does Pan-Retinal Photocoagulation Work?  The proliferative phase of diabetic retinopathy is notable for the presence of abnormal blood vessels growing on the surface of the retina or iris.  These abnormal vessels, called neovascularization, develop as a result of retinal ischemia.  Ischemia develops when blood supply is compromised to a tissue and inadequate oxygen supply is delivered to the tissues.  In the eye, this results in the production of VEGF (Vascular Endothelial Growth Factor) which basically acts as a fertilizer for the neovascularization.  By ablating enough of the peripheral retina, VEGF production ceases, and the neovascularization goes away.  Patients are now stable.

Ischemia   ——–>    VEGF   ——–>  Neovascularization

Does this Decrease Vision? This does not change your central vision.  The PRP treats the so-called “peripheral” retina which may, but usually does NOT, change your peripheral vision.  Sometimes, there may be some decrease in going from light to dark situations and vice versa, for example, walking out of a movie theater in the afternoon.  Basically, we treat the peripheral retina, to save the central vision – the most important “vision.”

Central Vision is Preserved. In general, when epeople speak of “vision,” we actually are speaking of central vision.  Central vision is provided by the macula, the tiny 2mm X 2mm functional center of the retina.  It gives us our 20/20 vision, our ability to “stare” at something and gives us the best color and reading vision.

Proliferative diabetic retinopathy does not occur in every diabetic.  When caught early, as in the cases above, a life-time of excellent vision can be expected.


Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist

Reblog this post [with Zemanta]


Currently, I see patients with retinal diseases; macular degeneration, retinal detachment, macular holes, macular pucker within several different's a different arrangement, but it allows more continuous care with many eye specialists. In addition, I am very accessible via the web. To schedule your own appointment, call any of the numbers below.

Virginia Lasik | Office of Anh Nguyen, M.D.
Randall V. Wong, M.D.
Contact: Layla

A: 431 Park Avenue, Suite 103 • Falls Church, Virginia 22046
Ph: 703.534. 4393
View Map

Dressler Ophthalmology Associates, PLC
Randall V. Wong, M.D.
Contact: Ashley (Surgery/Web)
Chrissy Megargee (Web)

A: 3930 Pender Drive, Suite 10 • Fairfax, Virginia 22030
Ph: 703.273.2398
F: 703.273.0239
View Map