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The Moran Eye Center has been involved in many of…
Date Recorded
April 23, 2014 Health Topics (The Scope Radio)
Vision Transcription
Man: Medical news and research from the University of Utah physicians and specialists you can use for a happier and healthier life. You're listening to The Scope.
Interviewer: Dr. Paul Bernstein at the Moran Eye Center. Let's talk about some of the trials and some of the work and research that have been done into AMD and what you've discovered.
Dr. Paul Bernstein: Okay. We at the Moran Eye Center have been very involved in many of the key clinical studies for age-related macular degeneration. One of our primary treatments is a drug called Lucentis, which involves injections once a month of a medicine into the eye every month for age-related macular degeneration for the wet form.
Interviewer: And that's where the veins are starting to come into the eye?
Dr. Paul Bernstein: That's correct.
Interviewer: What does this medication do? Does it just stop that?
Dr. Paul Bernstein: The Lucentis and similar drugs, when injected into the eye, combat the growth of blood vessels. They actually interact with the signal to grow blood vessels, a compound called VEGF or vascular endothelial growth factor.
Interviewer: We learned in our previous podcast that what's going on there is that those cells are sending those signals to grow those blood vessels, and this tells it to stop.
Dr. Paul Bernstein: Yes.
Interviewer: Okay.
Dr. Paul Bernstein: It just blocks the signal right there.
Interviewer: Gotcha.
Dr. Paul Bernstein: It binds them, and the signal can no longer interact with the receptor to grow the blood vessels, and the blood vessels that are abnormal begin to get smaller and kind of wither away. After the drug wears off in a month or so, we have to give another injection into the eye.
So, we're trying to develop longer acting versions of the drug, and we're involved in some early stage clinical trial planning of either reservoirs that can be implanted into the eye that will slowly release a compound that would block vascular endothelial growth factor. We're also trying to look at different ways to get the medicine across the sclera, across the white part of the eye instead of using a needle, trying to use electrical impulses to get the drug to cross the eye.
Interviewer: Interesting.
Dr. Paul Bernstein: We would love to have a drug that could be just given as an eye drop. As you know, we have many medicines we give as eye drops. The challenge is that the retina is the back of the eye, and trying to get a drug to go all the way back and interact with the retina is difficult. Drug companies are very actively trying to improve that process.
Interviewer: So I suppose a pill, an orally taken thing, is just completely out of the question?
Dr. Paul Bernstein: People are looking at pills for macular degeneration that could combat the growth of blood vessels. The process is the macula and the eye is a very small part of the body.
Interviewer: Yeah.
Dr. Paul Bernstein: You have to worry about side effects and other reactions.
Interviewer: Sure.
Dr. Paul Bernstein: We certainly like the idea of local delivery, of targeted delivery to the eye.
Interviewer: Yeah. That's interesting. And what other kind of research of trials are you involved in or do you have going on?
Dr. Paul Bernstein: Well, we were one of the centers for the Age-Related Eye Disease Study, too, the AREDS 2 Study. We're really trying to understand the role of nutrition and nutritional supplements in age-related macular degeneration. This was a very large trial. There were nearly 100 centers across the country. Over 5,000 patients were in the study. It lasted five years. They had to come in every few months for eye examinations and to be given their supplements or placebos. It was definitely a placebo-controlled trial to really understand how these supplements work.
Interviewer: In a situation like that, I think you gave me a hint. How would you even know where to start and what to look for as far as nutrition that might be helpful? It sounds like you said these two things are high concentration in the eye, and that's where you started.
Dr. Paul Bernstein: Yes. So, the lutein and zeaxanthin are particularly interesting because the macula, which we all hear about for macular degeneration, is technically the macula lutea, which means "yellow spot" in Latin. And the macula uniquely in humans and fellow primates concentrates yellow compounds from our diet, the lutein and zeaxanthin. So I was always fascinated as to why nature went out of its way to put these two compounds that are antioxidants and light screening compounds directly into the back of the eye.
Interviewer: So somebody would take this supplement, and you would look to see if the concentration increased in their eye. Is that what you were looking for?
Dr. Paul Bernstein: That was in part. We were a sub-study in the trial to do measurements of the macular pigment levels, but ultimately for a national eye institute sponsored study, we're looking to see if it is effective with whether we can decrease the rate of progression to advanced age-related macular degeneration. That was the ultimate endpoint in the study. We have to see that we are getting an effect.
Interviewer: Yeah. Because if you increase those compounds, who cares if it's not solving the problem?
Dr. Paul Bernstein: That's exactly right.
Interviewer: Yeah. Interesting. What else do you have going on? You mentioned something on the horizon. Can you talk about that a little bit?
Dr. Paul Bernstein: We are looking at some other trials trying to interact with the immune system and the complement system. There is some exciting work as some of my colleagues here in the Genetics have discovered that the inflammatory system in the eye may be part of macular degeneration. So drug companies are developing new compounds that could interact with the complement system. Those are very early stage trials, and we're very hopeful that we can get involved in preventing macular degeneration earlier.
Other studies are to improve the compounds that we use to treat wet macular degeneration by doing combinations. Just like in cancer and chemotherapy, we know that there are multiple pathways that need to be attacked, and we are about to be a part of a new study that will be involved in even a second injection in the eye of a different compound. So it's a large commitment for patients to be in studies such as that.
Interviewer: So what's the theory there with the inflammatory system that's causing the problem? Is that, like, inflammation in other parts of my body, but it's happening in my eye? What would cause that?
Dr. Paul Bernstein: Inflammation as part of macular degeneration relates, we think, to the formation of drusen, the yellowish deposits we see underneath the retina. That is a very important sign of early macular degeneration. This causes damage to the cells and also contributes to the stimulus of new blood vessel growth underneath the retina.
Interviewer: So the thought that this is happening in the immune system that's trying to fight it is actually causing more harm than good. Is that what I'm hearing?
Dr. Paul Bernstein: We think that there may be a problem, and modifying that, that's what we need to test in these trials.
Interviewer: Any final thoughts for our listeners about the future of research trials?
Dr. Paul Bernstein: We always are looking to improve treatments. We've been very gratified by the improvements that have occurred in the last two decades for macular degeneration. We especially appreciate the commitment that the patients who join these trials have committed to this to trying to help both themselves and to others.
Interviewer: Could somebody listening be part of one of these trials? How would they make that happen?
Dr. Paul Bernstein: They need to talk with their doctor.
Interviewer: Okay.
Dr. Paul Bernstein: If you have macular degeneration, the best thing is to ask your doctor. Ask what trials are available, and how they could be improved on the standard therapy that we have now.
Man: We're your daily dose of science, conversation, medicine. This is The Scope, University of Utah Health Sciences Radio.
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Age-related macular degeneration is the leading…
Date Recorded
April 18, 2014 Health Topics (The Scope Radio)
Vision Transcription
Interviewer: If you've had a relative with macular degeneration you know how heartbreaking it can be to watch them lose their sight; and a little terrifying for you, too, because you've got to wonder if you're next. We're doing to discuss that next on The Scope.
Recording: Medical news and research from University Utah Physicians and Specialists you can use for a happier healthier life. You're listening to The Scope.
Interviewer: Coming up today on The Scope we're going to talk about macular degeneration. We're going to cover what it is, what are the risk factors that could help you get it, what you can do to prevent it, and some possible treatments. We're with Dr. Paul Bernstein of the Moran Eye Center.
First of all macular degeneration, or also called AMD, what's going on? There are two different types if I understand correctly.
Dr. Paul Bernstein: Yes, age related macular degeneration is the leading cause of blindness in the developing world. And there are two types and it affects the central part of vision called the macula. The macula is the area of the eye that is responsible for reading, driving, recognizing faces, and in age related macular degeneration there is a dry form, which is a slow form that progresses slowly over years if not even decades, it can eventually lead to central blindness in the eye.
And there is the wet form which involves growth of new blood vessels under the retina and this can have a much more rapid course and lead to loss of vision in a matter of days or weeks.
Interviewer: So the dry form, what exactly is happening in the eye?
Dr. Paul Bernstein: In the dry form initially it starts with deposits forming underneath the retina; something that we call drusen that are yellowish spots under the retina. The patient may have completely normal vision, and not have any symptoms. But eventually there is more malfunction of the cells of the retina and some of them begin to die in the center of the macula and that is why the center of the retina no longer senses light properly, and that can lead to blindness.
Interviewer: So it's like a camera not being able to sense light?
Dr. Paul Bernstein: That's correct; it's a problem of a camera with bad film.
Interviewer: And in the wet you're actually getting some growth back there and that's blocking your vision?
Dr. Paul Bernstein: That is disturbing the vision.
Interviewer: Okay.
Dr. Paul Bernstein: It's interrupting the retina from having contact with its supporting cells, and eventually this can damage both types of cells as these blood vessels get in between these two layers and they can bleed. They can leak fluid, and eventually they can form scars and that's what leads to loss of vision there.
Interviewer: What's going on? Why are those starting to grow there?
Dr. Paul Bernstein: We don't know completely, but we understand that with age there is some malfunction of the cells and they for reasons that we don't completely understand start sending out signals and that seems to be an important factor for causing these blood vessels to start to grow underneath the retina. So it's kind of a malfunction; it's the wrong signals being sent out, that's correct.
Interviewer: All right, so who is at risk for age related macular degeneration? I think the name kind of gives you some sort of an indication?
Dr. Paul Bernstein: Yes, there are many risk factors, and certainly age is one of the most important ones. We know that age related macular degeneration is not very common in the people in the 50 to 60 year old range. Only a couple percent of people show the signs, but as we age it rises almost exponentially so that over age 75 at least 30% to 35% of people show at least some signs of age related macular degeneration.
Interviewer: So it's hereditary, so if you get old enough you're just going to get it?
Dr. Paul Bernstein: Well, there are a number of important risk factors for age related macular degeneration. And these genes are risk factors and we know of two very important ones; one on chromosome 1 related to complement and inflammation. And another one on chromosome 10 that we still don't quite understand, but if you have the wrong combination of genes that you've inherited from your parents it can put you at much, much higher risk. It can raise your risk three, five, even tenfold higher than the average population.
Other things that we also know as risk factors include being Caucasian; it is much more common in light skinned populations to have age related macular degeneration. And we also know in terms of modifiable risk factors that smoking is the number one modifiable risk factor. If you are a smoker, it increases your risk of developing the wet form of macular degeneration many fold and we certainly encourage our patients not to smoke.
And then the other area that I'm quite interested in is nutrition. We've learned that nutrition is very important in helping to prevent age related macular degeneration; specifically dark green leafy vegetables, orange and yellow fruits and vegetables, and cold water fish are certainly things that we recommend even in children at risk for age related macular degeneration because their parents have macular degeneration. And in the patients with macular degeneration we often recommend that they take supplements because it's often hard to change diet late in life.
Interviewer: How much do you know about the direct causation of diet?
Dr. Paul Bernstein: We know that diet is very important. And there is accumulating research that modifying diet can change the levels of the lutein and zeaxanthin which are from the dark green leafy vegetables that are actually accumulated in the eye. So we know that diet can make a difference, but as I said, when people are older changing their diet is difficult and that's why through the Areds 2 Study...
Interviewer: And what does AREDS stand for?
Dr. Paul Bernstein: AREDS stands for Age Related Eye Disease Study.
Interviewer: Okay.
Dr. Paul Bernstein: And that most recently specifically looked at adding lutein and zeaxanthin, and omega 3 supplements to the vitamins that we already knew were effective against age related macular degeneration.
Interviewer: So what are some other things that you can do then? So you have these supplements, and do you really feel they are effective from what you've seen?
Dr. Paul Bernstein: I think they are, and I certainly . . . it's a big part of my practice, encouraging patients to take these supplements, because often my patients present they've lost vision in one eye, and they are very concerned that it's going to affect their other eye, because you can get by with good vision as long as you have good vision in one eye. But if you have age related macular degeneration that's significant in both eyes, it can be devastating to these otherwise well-functioning patients. We encourage them not to smoke. We also think that there is a negative role for excessive sunlight, so we encourage patients to wear sunglasses on bright sunny days. That's an easy thing to do.
Interviewer: And it sounds like all of these things that you're currently recommending are really pretty low impact? It's not like anything too serious. What's the risk of taking a few vitamins?
Dr. Paul Bernstein: We think that lutein, zeaxanthin, and the basic AREDS vitamins are very safe and few patients complain of side effects.
The other thing that I encourage my patients is to monitor their vision and to learn the early signs of age related macular degeneration, especially the conversion from the dry form to the wet form. With the wet form of macular degeneration we have developed very effective treatments now for this once almost universally blinding form of macular degeneration.
Interviewer: The wet form is actually treatable; dry form once it's started, not so much. Is that correct?
Dr. Paul Bernstein: That's correct. We are certainly looking at new treatments for the dry form, but currently the standard of care is just antioxidant vitamins and good diet.
Interviewer: Does the wet form always come before the dry form, or the dry form before the wet form?
Dr. Paul Bernstein: The dry form comes before the wet form. Okay, so and they almost always start with the dry form of macular degeneration, the slow form. The wet form can then rear its ugly head and we have to treat it and sometimes we get it back under control and still the dry form slowly progresses over time. Macular degeneration is a manageable disease; we'd like to make it a curable and a preventable disease, and that's what we're working on here.
Interviewer: If I have a family history of it can I get a genetic test and can you actually see if I have the gene mutations you were talking about?
Dr. Paul Bernstein: As a research tool, yes. We can and there are models that can predict that you have an increased risk. But it is I would caution a risk assessment, so not everyone even with the relatively high risk develops macular degeneration and other people develop macular degeneration for reasons that we don't completely understand. We are trying to figure out the role of the test still in clinical practice and in helping counsel people and that's part of further research that we will be conducting.
Recording: We're your daily dose of science, conversation, medicine; this is The Scope, University of Utah Health Sciences Radio.
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Teen doesn't let catastrophic eye injury…
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