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.
Tuesday, November 27, 2012
Wednesday, November 14, 2012
Genetic Testing for Macular Degeneration
Macular degeneration is a prevalent disease that is becoming more so with the aging population. 9.1 million Americans have macular degeneration today. A common question of patients is whether they should have a genetic test to determine if they are going to have macular degeneration or if their macular degeneration will progress to the advanced stage.
There are several companies that now offer genetic testing for macular degeneration. The tests examine certain genes that have been linked to macular degeneration such as complement factors, metabolic genes, energy metabolizing genes, extracellular matrix pathway genes. Then, the patient is stratified into categories based on the combination of their genes. Often, the testing is covered by insurance companies. However, the question is whether there is any benefit to the testing.
The American Academy of Ophthalmology recently addressed this question in a statement. Their position is that genetic testing for macular degeneration is NOT recommended. The position of the Academy is that screening exams are more productive for a patient than a genetic test that may or may not accurately predict the risk of AMD. Specifically, they state that "Although several genotypes are associated with increased risk for AMD, at this time, genetic testing provides no proven advantage in preventing or treating the disease." The Academy does suggest that in the future, treatments might be targeted based on genetic typing, at which time the testing would become valuable, but for now no such treatments exist. However, some argue that if a patient is high risk then he or she should have more frequent screenings to catch a neovascular membrane sooner. Currently, there are no studies that show more frequent screening in genetically high risk patients to be helpful.
Some patients do still chose genetic testing for macular degeneration for their own knowledge. This is certainly an option for such patients. However, even with a low risk score, patients should continue to undergo regular screening exams.
If you have questions about genetic testing and macular degeneration, consult your eye care professional.
This blog is for informational purposes only and is not intended to be medical advice. Please consult an eye care professional.
There are several companies that now offer genetic testing for macular degeneration. The tests examine certain genes that have been linked to macular degeneration such as complement factors, metabolic genes, energy metabolizing genes, extracellular matrix pathway genes. Then, the patient is stratified into categories based on the combination of their genes. Often, the testing is covered by insurance companies. However, the question is whether there is any benefit to the testing.
The American Academy of Ophthalmology recently addressed this question in a statement. Their position is that genetic testing for macular degeneration is NOT recommended. The position of the Academy is that screening exams are more productive for a patient than a genetic test that may or may not accurately predict the risk of AMD. Specifically, they state that "Although several genotypes are associated with increased risk for AMD, at this time, genetic testing provides no proven advantage in preventing or treating the disease." The Academy does suggest that in the future, treatments might be targeted based on genetic typing, at which time the testing would become valuable, but for now no such treatments exist. However, some argue that if a patient is high risk then he or she should have more frequent screenings to catch a neovascular membrane sooner. Currently, there are no studies that show more frequent screening in genetically high risk patients to be helpful.
Some patients do still chose genetic testing for macular degeneration for their own knowledge. This is certainly an option for such patients. However, even with a low risk score, patients should continue to undergo regular screening exams.
If you have questions about genetic testing and macular degeneration, consult your eye care professional.
This blog is for informational purposes only and is not intended to be medical advice. Please consult an eye care professional.
Monday, November 5, 2012
Diabetes and Eye Exams
Diabetes in an increasingly prevalent disease in the United States. One thing that many patients have questions and concerns about is when he or she should be seen for an eye exam to evaluate for diabetes in the eye.
Diabetic retinopathy is a leading cause of blindness in the US. Diabetes affects the small blood vessels in the retina and can lead to blurry vision and eventual blindness. However, the early, more treatable damage is asymptomatic and can only be discovered by routine screening exams.
So when should you have an eye exam? If you have Type 1 diabetes, your first eye exam should be within 1 year after diagnosis. If you have Type 2 diabetes, you should have an eye exam as soon as possible. Why the difference? Type 1 diabetes occurs suddenly and patients are usually diagnosed quickly after acquiring the diease. Type 2 diabetes can be present for years before the diagnosis. During this time, the damage could already be occurring and you may not even be aware of it!
Diabetic retinopathy occurs in several stages. The first stage is mild diabetic retinopathy. This is a few blood vessels that have become damaged and become weak. If you have mild retinopathy, you need at least a yearly exam. The second stage is moderate diabetic retinopathy. In this stage the damage is more extensive. We recommend patients with moderate retinopathy be seen every 6-12 months. Severe retinopathy can lead to permanent vision loss, so we recommend exams every 3-6 months. Proliferative retinopathy often requires treatment in the form of laser or surgery, so we see these patients every 3 months. Diabetic macular edema, the leading cause of vision loss from diabetes, can occur in any of these stages. Treatments such as laser and injections are available to treat this condition so follow-up can vary based on the patient. Only a dilated eye exam by a qualifed eye care professional can determine which type of retinopathy you have.
It is important to know that with regular screening and treatment, vision loss from diabetes can largely be avoided. So, if you have diabetes, be sure to see an eye care professional within the recommended time frame!
This blog is for informational purposes only and is not medical advice. Please consult an eye care professional.
Diabetic retinopathy is a leading cause of blindness in the US. Diabetes affects the small blood vessels in the retina and can lead to blurry vision and eventual blindness. However, the early, more treatable damage is asymptomatic and can only be discovered by routine screening exams.
So when should you have an eye exam? If you have Type 1 diabetes, your first eye exam should be within 1 year after diagnosis. If you have Type 2 diabetes, you should have an eye exam as soon as possible. Why the difference? Type 1 diabetes occurs suddenly and patients are usually diagnosed quickly after acquiring the diease. Type 2 diabetes can be present for years before the diagnosis. During this time, the damage could already be occurring and you may not even be aware of it!
Diabetic retinopathy occurs in several stages. The first stage is mild diabetic retinopathy. This is a few blood vessels that have become damaged and become weak. If you have mild retinopathy, you need at least a yearly exam. The second stage is moderate diabetic retinopathy. In this stage the damage is more extensive. We recommend patients with moderate retinopathy be seen every 6-12 months. Severe retinopathy can lead to permanent vision loss, so we recommend exams every 3-6 months. Proliferative retinopathy often requires treatment in the form of laser or surgery, so we see these patients every 3 months. Diabetic macular edema, the leading cause of vision loss from diabetes, can occur in any of these stages. Treatments such as laser and injections are available to treat this condition so follow-up can vary based on the patient. Only a dilated eye exam by a qualifed eye care professional can determine which type of retinopathy you have.
It is important to know that with regular screening and treatment, vision loss from diabetes can largely be avoided. So, if you have diabetes, be sure to see an eye care professional within the recommended time frame!
This blog is for informational purposes only and is not medical advice. Please consult an eye care professional.
Tuesday, October 30, 2012
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.
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.
Wednesday, October 24, 2012
Fluoroquinolones and retinal detachment?
A recent patient brought to mind the possible link between fluorquinolone antibiotics (ciprofloxacin, moxifloxacin, levofloxacin, etc) and the risk of retinal tears or detachments. Fluoroquinolones are one of the most often prescribed antibiotics, and if there is such a risk, could affect a large number of people.
An article posted in JAMA in April 2012 revealed a possible link between these antibiotics and retinal detachments. The article was a case control study of 989,591 patients who took the antibiotic between 2000-2007. 4384 patients had experienced a retinal detachment. Statistically, current use of fluoroquinolones carried a higher risk of retinal detachment but recent use and past use did not.
This article does not prove that fluorquinolones were the cause of the detachments, but merely suggests that there might be a correlation. The proposed mechanism is that the drug may have a destructive effect on collagen and connective tissue. In fact, there is a known risk between fluoroquinolone use and tendon rupture. Since the vitreous contains collagen, this could be the mechanism that leads to the increased risk of retinal detachment or tears.
So, what is the take home message of this possible risk? As a patient, be aware that there is a theoretical risk of retinal detachments with the use of this drug. If you are a prescriber, educate your patients about the signs of retinal tears and detachment such as flashes and floaters. If you are currently using a fluorquinolone antibiotic and experience flashes, floaters, or other symptoms of a retinal detachment, you should contact your physician and an eye care professional. They will perform an dilated exam to look for retinal pathology.
This blog post is for informational purposes only. It is not intended to medical advice. Please seek the advice of a qualified professional.
An article posted in JAMA in April 2012 revealed a possible link between these antibiotics and retinal detachments. The article was a case control study of 989,591 patients who took the antibiotic between 2000-2007. 4384 patients had experienced a retinal detachment. Statistically, current use of fluoroquinolones carried a higher risk of retinal detachment but recent use and past use did not.
This article does not prove that fluorquinolones were the cause of the detachments, but merely suggests that there might be a correlation. The proposed mechanism is that the drug may have a destructive effect on collagen and connective tissue. In fact, there is a known risk between fluoroquinolone use and tendon rupture. Since the vitreous contains collagen, this could be the mechanism that leads to the increased risk of retinal detachment or tears.
So, what is the take home message of this possible risk? As a patient, be aware that there is a theoretical risk of retinal detachments with the use of this drug. If you are a prescriber, educate your patients about the signs of retinal tears and detachment such as flashes and floaters. If you are currently using a fluorquinolone antibiotic and experience flashes, floaters, or other symptoms of a retinal detachment, you should contact your physician and an eye care professional. They will perform an dilated exam to look for retinal pathology.
This blog post is for informational purposes only. It is not intended to medical advice. Please seek the advice of a qualified professional.
Tuesday, October 16, 2012
At home visual acuity monitoring
SightBook is an application that you can download onto your iPhone or iPad that offers visual acuity testing, amsler grid testing, and various other vision tests.
When you register your account, it will record your results over time and allows you to not only keep track of your vision but also your treatments. The app will also notify you daily, weekly, or monthly to remind you that you need to take your test.
If your visual acuity changes, your application will automatically notify the physician you have selected.
Today, we have treatments for many vision threatening diseases, but prompt visits to your physician when you experience a change have been shown to improve your visual outcome over time. This free app allows you to keep track of your vision and be aware sooner of any changes.
To download the app, go to App Store and download SightBook. Make sure your register your account so that your results are stored and can be shared with your physician.
If you have an account and would like to add us, we are account number 149.
For more information, please go to www.digisight.net
Visit us at www.ncretina.com
When you register your account, it will record your results over time and allows you to not only keep track of your vision but also your treatments. The app will also notify you daily, weekly, or monthly to remind you that you need to take your test.
If your visual acuity changes, your application will automatically notify the physician you have selected.
Today, we have treatments for many vision threatening diseases, but prompt visits to your physician when you experience a change have been shown to improve your visual outcome over time. This free app allows you to keep track of your vision and be aware sooner of any changes.
To download the app, go to App Store and download SightBook. Make sure your register your account so that your results are stored and can be shared with your physician.
If you have an account and would like to add us, we are account number 149.
For more information, please go to www.digisight.net
Visit us at www.ncretina.com
Monday, October 15, 2012
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
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
Subscribe to:
Posts (Atom)