Dr. Brian Lewy- Dr. Jay Stockman
Americans have pursued a never ending search for nutrients, and supplements in an effort to improve ocular health and prevent eye diseases. While many advertized items have little or no actual benefit, there are some that have been shown to be helpful, and efficacious. Over the last half century research has started to embrace these supplements as beneficial to our health, and their impact on one’s general well being.
Understanding the aging, and physiological processes offers a pathway to the benefits of these nutrients. Cataracts, Macular Degeneration, dry eyes and other age related disorders are but a few of the considerations that these neutricuticals are targeted to address. A study conducted by West and associates concluded that there are some supplements that are very helpful and when taken properly will prevent damage and even do some repair.
Research conducted by the Age Related Eye Disease Study ( AREDS) found that individuals who took antioxidant combinations of 500 IU Vit C, 400 IU Vit E, 15 mg of beta carotene and Zinc for approximately 6 years had a 17%-21% lower rate of Age Related Macular Degeneration(ARMD) progression as compared to individuals in the placebo group. Patients who took Zinc or antioxidants alone also showed a decrease in the progression of ARMD, but not to the extend as the first group. No benefit was shown with the folks who took Vit E alone. In addition, participants who took Lutein for 18-20 weeks demonstrated higher plasma levels, and increased macular pigment density. This would counter the ARMD damage and improve visual quality.
The West and associate study found no benefit at all in preventing, improving or reversing the damage caused by Cataracts or Diabetic Retinopathy. Herbal remedies, antioxidants, and all vitamins were found to be useless with regard to these two conditions.
Unlike cataracts, Glaucoma has been shown to be aided by the use of supplements. Cannabinoids have demonstrated an ability to lower the intraocular pressure, thereby lowering the visual devastations of Glaucoma. The problem with this supplement is obtaining an accepted method of administration that is regulated, dose reproducible and legal. Additional studies have shown that Ginkgo Biloba has improved the visual fields of normal tension glaucoma patients with as little as four weeks of use. The reason is believed to be the vasodilating affect of this supplement. Bringing more blood, and oxygen to the starved retinal tissue. Bilberry has not been clinically demonstrated to aid glaucoma patients in any way.
While additional studies must be conducted to asses all the benefits of these, and other nutritional supplements, it is clear that some do help. Furthermore, of equal importance is the drug interaction of supplements with both each other and prescription medicines. Many herbs, drugs and supplements can and do increase/ decrease the affect of other substances when present at the same time. Care must always be taken and warnings displayed. In all cases, one must consult with their health care professionals as to what supplements can be safely used.
Saturday, November 22, 2008
Spotting eye disease sooner
Roxanne Stein
BACKGROUND: Macular degeneration is the age-related degenerative process of the macula. The macula is the area of the retina that is responsible for fine visual acuity. Macular degeneration can make it difficult or impossible to read and recognize faces and it's a major cause of blindness in the elderly. Age-related macular degeneration (AMD) begins with characteristic yellow deposits in the macula, called drusen. People with drusen can go on to develop advanced AMD. The risk is considerably higher when the drusen are large and numerous and associated with disturbance in the pigmented cell layer under the macula. Recent research suggests that large and soft drusen are related to elevated cholesterol deposits and may respond to cholesterol lowering agents.
There are two forms of AMD -- wet and dry. Central geographic atrophy, the dry form of AMD, results from atrophy to the retinal pigment epithelial layer below the retina, which can lead to blindness through loss of photoreceptors (rods and cones) in the central part of the eye. Neovascular or exudative AMD, the wet form of AMD, causes vision loss due to abnormal blood vessel growth in the choriocapillaries, ultimately leading to blood and protein leakage below the macula. Bleeding, leaking and scarring from these blood vessels can eventually cause irreversible damage to the photoreceptors and rapid vision loss if left untreated.
DIAGNOSING: The traditional way to diagnose macular degeneration has been with the Amsler Grid Test. The Amsler Grid is a pattern of intersecting lines, identical to a piece of graph paper, with a black dot in the center. A person with normal vision can fixate on the dot while still seeing the grid patterns. A person with macular degeneration will see part of the grid missing, or some of the grid lines will appear to be bent or unevenly spaced.
A new test called prospective hyperacuity perimetry, or PHP, is able to detect the change from dry to wet AMD. The computerized test is more accurate because it has a higher sensitivity level. It will detect a change from dry macular degeneration to the wet form faster or at an earlier stage than traditional testing. PHP testing works by showing a series of linear dots in a pattern and it tests the entire 14 degrees of the macular fields. It tests small portions at a time in a prearranged sequence. The patient is asked to detect if any of the dots arranged in a line are out of space. The PHP test also incorporates some dot sequences that really are out of order, allowing it to test a patient's reliability in answering. A computer records the data and can detect even the smallest changes in a patient's macula over time.
BACKGROUND: Macular degeneration is the age-related degenerative process of the macula. The macula is the area of the retina that is responsible for fine visual acuity. Macular degeneration can make it difficult or impossible to read and recognize faces and it's a major cause of blindness in the elderly. Age-related macular degeneration (AMD) begins with characteristic yellow deposits in the macula, called drusen. People with drusen can go on to develop advanced AMD. The risk is considerably higher when the drusen are large and numerous and associated with disturbance in the pigmented cell layer under the macula. Recent research suggests that large and soft drusen are related to elevated cholesterol deposits and may respond to cholesterol lowering agents.
There are two forms of AMD -- wet and dry. Central geographic atrophy, the dry form of AMD, results from atrophy to the retinal pigment epithelial layer below the retina, which can lead to blindness through loss of photoreceptors (rods and cones) in the central part of the eye. Neovascular or exudative AMD, the wet form of AMD, causes vision loss due to abnormal blood vessel growth in the choriocapillaries, ultimately leading to blood and protein leakage below the macula. Bleeding, leaking and scarring from these blood vessels can eventually cause irreversible damage to the photoreceptors and rapid vision loss if left untreated.
DIAGNOSING: The traditional way to diagnose macular degeneration has been with the Amsler Grid Test. The Amsler Grid is a pattern of intersecting lines, identical to a piece of graph paper, with a black dot in the center. A person with normal vision can fixate on the dot while still seeing the grid patterns. A person with macular degeneration will see part of the grid missing, or some of the grid lines will appear to be bent or unevenly spaced.
A new test called prospective hyperacuity perimetry, or PHP, is able to detect the change from dry to wet AMD. The computerized test is more accurate because it has a higher sensitivity level. It will detect a change from dry macular degeneration to the wet form faster or at an earlier stage than traditional testing. PHP testing works by showing a series of linear dots in a pattern and it tests the entire 14 degrees of the macular fields. It tests small portions at a time in a prearranged sequence. The patient is asked to detect if any of the dots arranged in a line are out of space. The PHP test also incorporates some dot sequences that really are out of order, allowing it to test a patient's reliability in answering. A computer records the data and can detect even the smallest changes in a patient's macula over time.
Ophthotech Enrolls First Patient in a Phase I Complement (Anti-C5) Inhibitor Trial for Macular Degeneration
ARC1905 Represents Second Compound in Clinical Development
PRINCETON, NJ and NEW YORK, NY--(Marketwire - October 27, 2008) - Ophthotech Corp. ("Ophthotech"), a privately held biopharmaceutical company focused on developing ophthalmic therapies for back-of-the-eye diseases, announced today the enrollment of its first patient in a complement inhibition trial for the treatment of age-related macular degeneration (AMD). This Phase I trial will assess the safety and tolerability of ARC1905, an anti-C5 complement factor aptamer, in combination with an anti-VEGF agent.
Dr. Donald J. D'Amico, Professor and Chairman, Department of Ophthalmology, Weill Cornell Medical College, New York-Presbyterian Hospital, and a member of Ophthotech's Scientific Advisory Board, said, "Multiple lines of evidence now point to a fundamental problem with inflammation and complement activation in patients with high susceptibility to develop AMD. Intervention in the complement pathway is the single most promising target for new therapeutic and preventive strategies for AMD."
"Preclinical and human genetic linkage studies strongly support the significant role of complement-mediated inflammation in both dry and wet AMD," said Samir Patel, M.D., President and Chief Executive Officer of Ophthotech. "We believe that anti-C5 aptamer blockade represents a potential breakthrough therapy for both wet and dry forms of AMD."
Published studies in Science, the New England Journal of Medicine and other leading journals suggest that abnormalities involving the complement pathway may be responsible for the majority of cases of dry and wet forms of AMD in the western world.
ARC1905 represents one of three compounds that Ophthotech is developing to treat AMD. Additional molecular entities include E10030, an anti-PDGF aptamer currently in a Phase I study, and volociximab, an anti-angiogenic monoclonal antibody targeting the alpha5beta1 integrin, which is on track to commence clinical trials in the near future.
About ARC1905
Anti-C5 aptamer ARC1905 inhibits C5, a central component of the complement cascade, which plays multiple roles in innate immunity and inflammatory diseases. Inhibition of this key step in the complement cascade at the level of C5 prevents the formation of key terminal fragments (C5a and C5b-9) regardless of which pathway (alternate, classical or lectin) induced their generation. The C5a fragment is an important inflammatory activator inducing vascular permeability, recruitment and activation of phagocytes. C5b-9 is involved in the formation of membrane attack complex (MAC: C5b-9), which initiates cell lysis. By inhibiting these C5-mediated inflammatory and MAC activities, therapeutic benefit may be achieved in both dry and wet AMD. In August 2007, Ophthotech licensed worldwide rights to all ophthalmic uses of Archemix's proprietary aptamers (ARC186 and ARC1905) targeting the C5 component of the complement cascade.
About E10030
E10030, currently being investigated in a Phase I trial, is an aptamer-based compound directed against PDGF-B. Pharmacology studies indicate that E10030 binds to PDGF-B with high specificity and affinity and inhibits the functions of PDGF-B both in vitro and in vivo. In preclinical studies, E10030 demonstrated the potential to regress neovascularization when used in combination with a VEGF-A inhibitor. In experiments involving models of ocular vascularization, concurrent inhibition of PDGF-B and VEGF-A signaling was superior to inhibition of the VEGF-A pathway alone.
About Volociximab (M200)
Volociximab is a monoclonal antibody targeting alpha5beta1 integrin, a key protein involved in the formation of new blood vessels, a process known as angiogenesis. alpha5beta1 integrin is a critical survival factor for proliferating endothelial cells involved in angiogenesis. Inhibition of alpha5beta1 integrin has demonstrated potent anti-angiogenic effects in multiple pre-clinical models of angiogenesis.
About AMD
AMD is the leading cause of blindness for people over the age of 50 in the United States and Europe. There are two forms of the disease, namely "dry" and "wet" AMD. The "wet" form is characterized by the growth of new blood vessels into the central region of the retina. These new vessels cause severe visual loss due to retinal damage caused by subsequent leakage and scar formation. Anti-VEGF therapies and photodynamic therapies have been approved for "wet" AMD. "Dry" AMD accounts for up to 90 percent of all cases of AMD. There is no approved therapy for "dry" AMD, which afflicts 8 million patients in the United States and an additional 8 million in Europe. Visual loss in "dry" AMD is typically not as severe as "wet" AMD, however, over time, "dry" AMD can progress to the wet form of the disease.
About Ophthotech
Ophthotech Corp. is a privately held biopharmaceutical company focused on developing and commercializing therapies for back-of-the-eye diseases. Ophthotech plans to develop a pipeline of compounds with strong scientific foundations for the treatment of AMD and bring them to market in an accelerated manner. In August of 2007, Ophthotech announced a Series A venture financing and two separate in-licensing deals with Archemix Corp. and Eyetech, Inc., which recently spun out of (OSI) Eyetech. A third in-license from Biogen Idec and PDL BioPharma was announced in January of 2008. Ophthotech's venture investors include SV Life Sciences, HBM BioVentures and Novo A/S. For more information, please visit www.ophthotech.com.
PRINCETON, NJ and NEW YORK, NY--(Marketwire - October 27, 2008) - Ophthotech Corp. ("Ophthotech"), a privately held biopharmaceutical company focused on developing ophthalmic therapies for back-of-the-eye diseases, announced today the enrollment of its first patient in a complement inhibition trial for the treatment of age-related macular degeneration (AMD). This Phase I trial will assess the safety and tolerability of ARC1905, an anti-C5 complement factor aptamer, in combination with an anti-VEGF agent.
Dr. Donald J. D'Amico, Professor and Chairman, Department of Ophthalmology, Weill Cornell Medical College, New York-Presbyterian Hospital, and a member of Ophthotech's Scientific Advisory Board, said, "Multiple lines of evidence now point to a fundamental problem with inflammation and complement activation in patients with high susceptibility to develop AMD. Intervention in the complement pathway is the single most promising target for new therapeutic and preventive strategies for AMD."
"Preclinical and human genetic linkage studies strongly support the significant role of complement-mediated inflammation in both dry and wet AMD," said Samir Patel, M.D., President and Chief Executive Officer of Ophthotech. "We believe that anti-C5 aptamer blockade represents a potential breakthrough therapy for both wet and dry forms of AMD."
Published studies in Science, the New England Journal of Medicine and other leading journals suggest that abnormalities involving the complement pathway may be responsible for the majority of cases of dry and wet forms of AMD in the western world.
ARC1905 represents one of three compounds that Ophthotech is developing to treat AMD. Additional molecular entities include E10030, an anti-PDGF aptamer currently in a Phase I study, and volociximab, an anti-angiogenic monoclonal antibody targeting the alpha5beta1 integrin, which is on track to commence clinical trials in the near future.
About ARC1905
Anti-C5 aptamer ARC1905 inhibits C5, a central component of the complement cascade, which plays multiple roles in innate immunity and inflammatory diseases. Inhibition of this key step in the complement cascade at the level of C5 prevents the formation of key terminal fragments (C5a and C5b-9) regardless of which pathway (alternate, classical or lectin) induced their generation. The C5a fragment is an important inflammatory activator inducing vascular permeability, recruitment and activation of phagocytes. C5b-9 is involved in the formation of membrane attack complex (MAC: C5b-9), which initiates cell lysis. By inhibiting these C5-mediated inflammatory and MAC activities, therapeutic benefit may be achieved in both dry and wet AMD. In August 2007, Ophthotech licensed worldwide rights to all ophthalmic uses of Archemix's proprietary aptamers (ARC186 and ARC1905) targeting the C5 component of the complement cascade.
About E10030
E10030, currently being investigated in a Phase I trial, is an aptamer-based compound directed against PDGF-B. Pharmacology studies indicate that E10030 binds to PDGF-B with high specificity and affinity and inhibits the functions of PDGF-B both in vitro and in vivo. In preclinical studies, E10030 demonstrated the potential to regress neovascularization when used in combination with a VEGF-A inhibitor. In experiments involving models of ocular vascularization, concurrent inhibition of PDGF-B and VEGF-A signaling was superior to inhibition of the VEGF-A pathway alone.
About Volociximab (M200)
Volociximab is a monoclonal antibody targeting alpha5beta1 integrin, a key protein involved in the formation of new blood vessels, a process known as angiogenesis. alpha5beta1 integrin is a critical survival factor for proliferating endothelial cells involved in angiogenesis. Inhibition of alpha5beta1 integrin has demonstrated potent anti-angiogenic effects in multiple pre-clinical models of angiogenesis.
About AMD
AMD is the leading cause of blindness for people over the age of 50 in the United States and Europe. There are two forms of the disease, namely "dry" and "wet" AMD. The "wet" form is characterized by the growth of new blood vessels into the central region of the retina. These new vessels cause severe visual loss due to retinal damage caused by subsequent leakage and scar formation. Anti-VEGF therapies and photodynamic therapies have been approved for "wet" AMD. "Dry" AMD accounts for up to 90 percent of all cases of AMD. There is no approved therapy for "dry" AMD, which afflicts 8 million patients in the United States and an additional 8 million in Europe. Visual loss in "dry" AMD is typically not as severe as "wet" AMD, however, over time, "dry" AMD can progress to the wet form of the disease.
About Ophthotech
Ophthotech Corp. is a privately held biopharmaceutical company focused on developing and commercializing therapies for back-of-the-eye diseases. Ophthotech plans to develop a pipeline of compounds with strong scientific foundations for the treatment of AMD and bring them to market in an accelerated manner. In August of 2007, Ophthotech announced a Series A venture financing and two separate in-licensing deals with Archemix Corp. and Eyetech, Inc., which recently spun out of (OSI) Eyetech. A third in-license from Biogen Idec and PDL BioPharma was announced in January of 2008. Ophthotech's venture investors include SV Life Sciences, HBM BioVentures and Novo A/S. For more information, please visit www.ophthotech.com.
Using Bifocal Reading Glasses
Telescopic glasses are among the latest of the numerous low vision aids used to help people in dealing with macular degeneration symptoms. While there is no cure for age related macular degeneration (AMD), there are macular degeneration treatments available that can assist such patients in maximizing what sight they do have; telescopic glasses are possibly among the most effective, both in terms of cost and effectiveness.
In some ways, these remarkable devices – also known as bioptics - are similar to bifocal reading glasses. They essentially work the same way; patients utilize these macular degeneration devices by tilting their heads forward. These particular macular degeneration devices are different however in their construction. Unlike bifocal reading glasses, which integrate two different prescriptions into single lenses, telescopic glasses actually consist of miniature telescopes that sit atop the frames.
The marvelous aspect of telescopic glasses – also known as bioptics - is the fact that they can be adjusted in the same way as many full-sized telescopes. As low vision aids for the relief of macular degeneration symptoms, telescopic glasses can be adjusted for a variety of activities requiring far, mid-range and near vision.
In fact, some states actually allow those who cannot pass the eye test for driving to operate a motor vehicle as long as bioptics are used. While there are usually restrictions, the use of telescopic glasses can help the patient to regain some measure of independence. These low vision aids are of great help in seeing road signs and other objects on the highway.
Telescopic glasses are like regular glasses, and if you plan on driving with them, you’ll need an optometrist’s prescription. Even if you’re not planning to operate an automobile (and admittedly, this is not appropriate for everyone – or even very many – people with macular degeneration symptoms), the use of these remarkable low vision aids can greatly add to your quality of life.
With the use of bioptics, people who use such macular degeneration devices can once again enjoy watching television and motion pictures, engage in artistic pursuits such as sculpture and painting or music requiring reading, and engage in their favorite sports.
Of course, because macular degeneration symptoms affect one’s central vision and because different activities in life require different kinds of vision, there is no one single solution. Bioptics are only one part of a comprehensive solution that will most likely require several different types of macular degeneration devices. Only your optometrist can advise you as to which of these prosthetic devices can be of most good in helping your particular case.
In some ways, these remarkable devices – also known as bioptics - are similar to bifocal reading glasses. They essentially work the same way; patients utilize these macular degeneration devices by tilting their heads forward. These particular macular degeneration devices are different however in their construction. Unlike bifocal reading glasses, which integrate two different prescriptions into single lenses, telescopic glasses actually consist of miniature telescopes that sit atop the frames.
The marvelous aspect of telescopic glasses – also known as bioptics - is the fact that they can be adjusted in the same way as many full-sized telescopes. As low vision aids for the relief of macular degeneration symptoms, telescopic glasses can be adjusted for a variety of activities requiring far, mid-range and near vision.
In fact, some states actually allow those who cannot pass the eye test for driving to operate a motor vehicle as long as bioptics are used. While there are usually restrictions, the use of telescopic glasses can help the patient to regain some measure of independence. These low vision aids are of great help in seeing road signs and other objects on the highway.
Telescopic glasses are like regular glasses, and if you plan on driving with them, you’ll need an optometrist’s prescription. Even if you’re not planning to operate an automobile (and admittedly, this is not appropriate for everyone – or even very many – people with macular degeneration symptoms), the use of these remarkable low vision aids can greatly add to your quality of life.
With the use of bioptics, people who use such macular degeneration devices can once again enjoy watching television and motion pictures, engage in artistic pursuits such as sculpture and painting or music requiring reading, and engage in their favorite sports.
Of course, because macular degeneration symptoms affect one’s central vision and because different activities in life require different kinds of vision, there is no one single solution. Bioptics are only one part of a comprehensive solution that will most likely require several different types of macular degeneration devices. Only your optometrist can advise you as to which of these prosthetic devices can be of most good in helping your particular case.
Friday, November 21, 2008
Medical Treatment
- Antioxidants: Deficiencies in antioxidants (specifically zinc and vitamins A, C, and E) have been noted in some people with age-related macular degeneration. Antioxidants may protect against age-related macular degeneration by preventing free radicals or unstable oxygen from damaging the retina.
- Laser treatment: Clinical trials have demonstrated the value of laser treatment for some people with the wet form.
- Laser treatment may stop or lessen vision loss in early stages of the disease.
- A laser beam destroys existing blood vessels and may stop the growth of new ones.
- A scar forms after the laser treatment. This produces a permanent loss of vision in that area of the retina, sacrificed in order to preserve the rest of the eye layer.
- Vision usually does not improve after laser treatment. It works in about half the cases, and only a small number of people meet the criteria for laser treatment. Its limitations have prompted a search for other forms of therapy.
- Laser treatment may stop or lessen vision loss in early stages of the disease.
- Photodynamic therapy: In April 2000, the U.S. Food and Drug Administration (FDA) approved this treatment. A light-activated drug called verteporfin (Visudyne) is given intravenously and uses a laser to close the abnormal vessels while leaving the retina intact. You may need several treatments over one to two years because closed blood vessels can reopen within the treated area. Because Verteporfin is activated by light, exposure to sunlight must be avoided for five days after treatment.
- Antioxidants: Deficiencies in antioxidants have been noted in some people with age-related macular degeneration. Antioxidants may protect against age-related macular degeneration by preventing free radicals or unstable oxygen from damaging the retina.
- A variety of drugs that block vascular endothelial growth factor (VEGF) are being evaluated as a treatment option.
No one has found a treatment of or a cure for the dry form of age-related macular degeneration.
The wet form of age-related macular degeneration is more likely than the dry form to cause significant vision loss. Different treatments of the wet form are available and may help decrease the amount of vision that is lost.
Subscribe to:
Posts (Atom)
