How many injections will I get for macular degeneration?

One of the most common questions we get asked by patients receiving injections for exudative (wet) macular degeneration is how many injections that they will have to receive.  Understandably, most patients are anxious to decrease or even stop their injections all together.  The answer, however, is variable depending on the patient.

Exudative macular degeneration is a chronic disease where the blood vessels in the choroid (the back of the eye) grow through a barrier called Bruch's membrane and bleed.  This bleeding leads to fluid in the macula which is what leads to decreased vision.  Chronic fluid and blood can lead to scarring and eventually markedly decreased central vision. The primary driving force between these blood vessels is a protein called vascular endothelial growth factor (VEGF).  The medications that we currently use to treat macular degeneration-  including Avastin, Lucentis, and Eylea-block this protein (anti-VEGF medications).

When the anti-VEGF medications are injected into the eye they only have an effect for about 28 days. After the medications wear off, the VEGF proteins made in the eye rise again and cause the vessels to leak or grow.  That is why the medications have to be injected at regular intervals.  I often compare this to having to take your blood pressure medication every day to keep your pressure under control.  The medications aren't a cure, but a treatment.

In the initial trials for anti-VEGF medications, the injections were continued every 28 days for 2 years regardless of the patient's vision or amount of fluid in the retina.  The results were excellent- stabilization of vision in most patients and increased vision in many patients.  In the years since the initial trials, a few different approaches have been tried to decrease the number of injections including treating only as needed when fluid returns, and a treatment called treat and extend where we gradually increase the time between injections. One medication, Eylea, is often used very 8 weeks after a 3 to 6 month initiation with monthly injections with good success.

One recent trial, HORIZON, examined the use of as needed injections and revealed that patients lost some vision that they had initially gained when only receiving the injections as needed (when fluid returned in the macula) instead of on a strict schedule.  So, many retina physicians concluded that either monthly treatments or a slow treat and extend regimen is more beneficial to the patient.  And, we know that if we stop the injections all together, the blood often returns and leads to severe central vision loss.

As cumbersome as monthly injections seem to you as a patient, it is important to realize the benefit you are likely receiving from your injections.  The anti-VEGF medications have revolutionized the treatment of this blinding disease and have given hope to many patients who did not have a good visual prognosis in the past.

Researchers are working to develop longer acting medications and other methods that could help avoid these monthly or ever other month injections, so some day in the future you may be able to decrease your visits to the retina physician for macular degeneration treatment.

Each patient is different and is evaluated by his or her physician to determine the best course of treatment.

This blog is for informational purposes only and is not intended to be medical advice.  Please consult your physician for any medical advice.

A New Drug For Exudative AMD?

Exudative, or wet AMD, is a blinding condition that many of our patients deal with. In fact AMD is the leading cause of blindness in the developed world.  Wet AMD is caused by neovascularization, or new blood vessels, that grow under the macula and then "leak" into the center of the vision and create vision loss.

Currently, the standard of care for wet AMD is injections of Anti-VEGF (vascular endothelial growth factor) medications.  These medications, Lucentis, Avastin, and Eylea, all work similarly in that they inhibit VEGF, a compound that encourages new blood vessel growth.  These injections are usually given monthly for 3 months and then either as needed or extended to longer intervals.  Anti-VEGF medications have been very successful in helping patients retain or even improve their vision after their AMD has become wet.

Even though we have seen great strides in vision improvement since the introduction of these medications, patients and physicians are always looking for further improvement. Platelet derived growth factor (PDGF) is another component of the neovascular cascade that creates the complex in wet AMD.  It has been the source of research for several years, and now promising phase 2b data has been released.

Ophthotech is a biopharmaceutical company that specializes in the creation of medications to treat AMD.  They have recently completed phase 2b testing on Fovista.  Fovista is a PDGF-B inhibitor.  The compound inhibits the growth of the lining of the vessel walls, and with the combination of anti-VEGF was seen in lab studies to induce the regression of neovascular complexes.

In phase 2b testing of 449 patients, Fovista in combination with Lucentis was superior to Lucentis alone in terms of vision gain.  10.2 letters of vision gain was observed with combination therapy while on 6.5 letters were gained with Lucentis alone.  This represented a 62% benefit.

What does this mean for you?  Well, Fovista must now undergo Phase 3 testing before it can be presented to the FDA for approval.  Phase 3 testing involves treating larger numbers of people with the drug to insure that it does indeed continue to provide the increased benefit over Lucentis monotherapy in a larger sample of patients.  There is no information on when Phase 3 trials will begin, but our blog will keep you updated with the progress of this potentially beneficial drug.

You can read about Fovista at www.opthotech.com

This blog is for informational purposes only and is not intended to be medical advice.  Please seek the advice of a qualified medical professional.

Antibiotics after intraocular injections

Intravitreal injections for macular degeneration, diabetic macular edema, and other conditions are becoming more and more common. The risk of endophthalmitis, or infection in the eye, is the most concerning ocular risk of these injections.  Recently, vitreoretinal surgeons have been changing their minds about antibiotics before, during, and after intravitreal injections and many patients have questions about the sudden change.

When intravitreal injections first began for macular degneration, they were a newer procedure.  We  had done a few before for various conditions, but never before in the quantity and regularity we are doing them now.  For many intraocular procedures such as cataract surgery, glacuoma surgery, or even retinal surgery, post-operative antibiotic drops are recommended.  So, we routinely used them after intravitreal injection.

In 2011, an ARVO poster from Bascom Palmer showed that with merely providone-iodide pre and post injection, and no post-operative antibiotic drops, there was no greater risk of post-injection infection (1).  An article was then published showing routine use of post-injection antibiotics selects resistant bacteria (2).

Subsequently, in 2012, a large study of 15,895 patients was published that showed infeciton rates by Cheung, et al 5 in 8259 for patients who were given antibiotics for 5 days after injection, 2 in 2370 for those who received antibiotics immediately after each injection, and 2 in 5266 who received no antibiotics.  There was no statistically significant difference amongst the groups.  Several smaller studies have all confirmed that the risk remains about 1 in 1000 to 1 in 5000 patients that get an infection after intravitreal injection.

In light of all of the data showing no benefit to antibiotic drops after injection, and data suggesting maybe a negative effect of antibiotic drops after injection, many retina specialists have stopped using them post injection.

If you have any signs of infection after your injection such as decreasing vision, increasing eye pain, or redness or swelling of the eye or eyelid, you should contact your eye physician.

This is not intended to be medical advice and is for informational purposes only. Please consult a qualified eye care professional if you have questions or concerns.


1. Rumya R. Rao, Golnaz Javey, Philip J. Rosenfeld, William J. Feue. Elimination of Post-Injection Topical Antibiotics after Intravitreal Injections. ARVO May, 2011
2.  Kim SJ, Toma HS. Ophthalmic antibiotics and antimicrobial resistance a randomized, controlled study of patients undergoing intravitreal injections.Ophthalmology. 2011 Jul;118(7):1358-63. Epub 2011 Mar 21.

Avastin and Compounding

The recent fungal meningitis outbreak has brought to light the possible consequences of compounded drugs. The outbreak occurred from a contaminated steroid injection into the spinal cavity.

We, as retina specialists, often use compounded medications in the form of Avastin as an intraocular injection. Intravitreal Avastin is used to treat macular degeneration, retinal vein occlusions, and diabetic macular edema.

A compounded medication is one that is removed from a larger vial and mixed to smaller concentrations or dosages and then sent for use.  This process occurs for many medications that are used for a vast array of conditions. Since one vial creates many doses, one contamination can affect a large number of people.

Lucentis and Eylea, also used to treat macular degneration, retinal vein occlusions, and diabetic macular edema, are not compounded medications.  They arrive at our office in a one time use vial.  Therefore the risk of one single vial affecting multiple people is zero.  However, there is always a risk of infection using any medication for intraocular injection.

Many patients have become concerned about the risk of receiving Avastin since it is a compounded medication.  However, this is a complex discussion that is best had between the treating physician and the patient. Overall, patients need to weigh all of their choices when receiving any treatment or considering changing treatment regimen.

This is for informational purposes only and not intended to be medical advice. Please consult a medical professional for medical advice.

Please visit us at www.ncretina.com