Fran Lowry
Cataract surgery does not appear to increase the progression of age-related macular degeneration (AMD). Instead, it might reveal pre-existing AMD that had been hidden by the cataract, suggests a new study published in the November issue of the Archives of Ophthalmology.
"There has been a longstanding controversy among clinicians as to whether cataract surgery is contraindicated in eyes with nonneovascular AMD," write Li Ming Dong, PhD, from Stony Brook University School of Medicine in New York, and associates from Johns Hopkins University School of Medicine in Baltimore, Maryland. "A major concern has been whether cataract surgery increases the risk of progression to neovascular AMD in eyes at risk of progression, such as those with intermediate AMD (extensive medium-sized drusen, large drusen, or nonfoveal geographic atrophy)."
The aim of this study was to evaluate the course of AMD during the year after cataract surgery in individuals with preconfirmed nonneovascular AMD.
The investigators analyzed 86 patients with nonneovascular AMD who underwent cataract surgery to note the incidence of neovascular AMD development in the 12 months after the operation. Only 1 eye from each patient was analyzed.
Fluorescein angiography was performed preoperatively, and at 1 week, 3 months, and 12 months postoperatively.
The median age of the patients was 76 years (range, 58 to 92 years); 48% were women, 97% were white, and nearly two thirds were current or former cigarette smokers. The median preoperative visual acuity (Snellen equivalent) was 20/50 (range, ≥20/40 to 20/400).
Photographic documentation of AMD status was done in 71 patients (83%) at the 12-month visit. Sixty-six patients (77%) also completed a clinical examination at this visit.
Neovascular AMD was observed in 9 eyes (12.7%; 95% confidence interval [CI], 6.0% - 22.7%) by 12 months, including 1 that was graded as probable neovascular AMD. Five eyes displayed signs of neovascular AMD at the 1-week follow-up, but the size and location of the lesions indicated that they might have been present before surgery but not visible because of the opacity caused by the cataract, the authors report.
One eye did not have a 1-week follow-up. After excluding this eye, as well as the 5 eyes that showed lesions at the first follow-up period, the rate of confirmed progression to neovascular AMD between week 1 and month 12 decreased to 3 (4.6%) of 65 eyes (95% CI, 1.0% - 12.9%), the investigators report.
The investigators also noted the progression to neovascular AMD in the study subjects' phakic contralateral eyes. They report that neovascular AMD developed in only 1 eye (3%) at 12 months.
Previous Reports Might Be Biased
"Our findings suggest that previous reports of the association or progression of nonneovascular AMD to advanced AMD after cataract surgery could be biased by the absence of immediate preoperative and postoperative fluorescein angiography to rule out pre-existing neovascular AMD or geographic atrophy," the study authors write, adding that a strength of their study — the first to their knowledge — was the use of color fundus photographs and fluorescein angiography in the immediate pre- and post-cataract surgery setting.
However, they point out, their study is limited by its small size and limited duration of follow-up to just 12 months. In addition 15 eyes (17%) at risk for neovascular AMD had to be excluded from the analysis because their postsurgery AMD status at 12 months could not be determined because of unavailable or ungradable images.
"Only a small percentage of study participants with AMD had definite progression to either neovascular AMD or geographic atrophy within 1 year of cataract surgery when eyes were carefully monitored with immediate preoperative and postoperative fundus photographs and fluorescein angiograms," the study authors conclude. "Our findings do not support the hypothesis that cataract surgery accelerates the progression of AMD."
In an accompanying editorial, Barbara E. K. Klein, MD, MPH, from the University of Wisconsin in Madison, writes that several reports have shown an association between cataract surgery and AMD since the late 1980s.
"Some report a cross-sectional association, some, incidence of AMD after surgery, and yet others report progression to more severe AMD. Still, there are some studies that do not find a significant association after controlling for relevant confounders. What might explain the disparate results? In my estimation, the diversity of findings in no small part begins with differences in study design," Dr. Klein noted."
Discussing these inconsistencies will help patients and their physicians make a more informed decision about the risks for progression to early AMD and development of late AMD after cataract surgery, she writes. "Until we have better information regarding the risk of developing AMD in those undergoing cataract surgery, it is the best we can do for our patients."
For more information go to www.maculardegenerationassociation.org
Monday, November 16, 2009
Monday, November 9, 2009
Obese Britain Blind to Risk of Sight Loss
ANDOVER, England,
As the UK's obesity crisis burgeons, millions of overweight Brits are blind to the fact that their unhealthy lifestyles mean they are twice as likely to lose their sight as someone with a normal BMI (Body Mass Index).
A shocking new report launched by the sight charity Eyecare Trust and healthcare provider Simplyhealth to mark National Eye Week (9-15 November 2009) reveals that just eight per cent of us associate obesity with sight loss(1), despite weight being a major risk factor in the onset and progression of many sight-threatening eye conditions.
With more than half of all adults across the UK tipping the scales above their recommended weight and a staggering 23 per cent now classed as obese (2), millions of Brits are needlessly putting themselves at risk of poor vision or even worse - total sight loss.
Iain Anderson, Chairman of the Eyecare Trust warns: "Carrying excess weight causes pulmonary problems which can lead to irrevocable damage to the delicate blood vessels in the eye. A Body Mass Index of 30 or more doubles your risk of age-related macular degeneration - the UK's leading cause of blindness - and significantly increases your chances of developing cataracts or glaucoma."
The survey also found that people's perceptions about weight - and in particular obesity - are seriously wide of the mark. For example, four fifths of those polled (82 per cent) believed a man of 6ft weighing 13st 3lb is healthy, when in fact he is overweight.
Iain continues: "While people are more likely to be aware of threat to eye health from factors such as smoking, excessive alcohol consumption or poor diet, they just don't make the connection with obesity, which can also put people at risk of diabetic retinopathy whether or not they suffer from diabetes." The strong links between obesity and eye disease have been affirmed by recent international research undertaken by eminent ophthalmologists in Israel and Singapore(3).
Regular sight tests are vital for the early diagnosis and treatment of these eye conditions, yet the National Eye Week 'See the Benefit' poll found that obese people were the group least likely to visit their optician. Worryingly, the survey reveals that those with a BMI in excess of 25 are most likely to believe their eyes are in a state of 'good' or 'very good' health(4).
Raman Sankaran of Simplyhealth says: "As well as lifestyle choices having an impact on eye health, the research also worryingly found that cost - or the issue of perceived cost - affects whether people attend regular sight tests. In fact 75 per cent of people admit to putting off having their eyes tested due to the price of the examination and the expense of glasses or contact lenses if needed.
"Attending a sight test needn't be expensive or act as a barrier to good eye health as there are many options available to help people budget for eyecare, such as a cash plan from Simplyhealth," Raman adds.
The Eyecare Trust recommends that everyone should have an eye examination every two years, unless advised otherwise by an optometrist. As well as providing a valuable insight into the health of your eyes a sight test also acts as an essential general health check uncovering a number of other underlying health problems such as high cholesterol, high blood pressure, diabetes and an increased risk of stroke.
For more information go to www.maculardegenerationassociation.org
As the UK's obesity crisis burgeons, millions of overweight Brits are blind to the fact that their unhealthy lifestyles mean they are twice as likely to lose their sight as someone with a normal BMI (Body Mass Index).
A shocking new report launched by the sight charity Eyecare Trust and healthcare provider Simplyhealth to mark National Eye Week (9-15 November 2009) reveals that just eight per cent of us associate obesity with sight loss(1), despite weight being a major risk factor in the onset and progression of many sight-threatening eye conditions.
With more than half of all adults across the UK tipping the scales above their recommended weight and a staggering 23 per cent now classed as obese (2), millions of Brits are needlessly putting themselves at risk of poor vision or even worse - total sight loss.
Iain Anderson, Chairman of the Eyecare Trust warns: "Carrying excess weight causes pulmonary problems which can lead to irrevocable damage to the delicate blood vessels in the eye. A Body Mass Index of 30 or more doubles your risk of age-related macular degeneration - the UK's leading cause of blindness - and significantly increases your chances of developing cataracts or glaucoma."
The survey also found that people's perceptions about weight - and in particular obesity - are seriously wide of the mark. For example, four fifths of those polled (82 per cent) believed a man of 6ft weighing 13st 3lb is healthy, when in fact he is overweight.
Iain continues: "While people are more likely to be aware of threat to eye health from factors such as smoking, excessive alcohol consumption or poor diet, they just don't make the connection with obesity, which can also put people at risk of diabetic retinopathy whether or not they suffer from diabetes." The strong links between obesity and eye disease have been affirmed by recent international research undertaken by eminent ophthalmologists in Israel and Singapore(3).
Regular sight tests are vital for the early diagnosis and treatment of these eye conditions, yet the National Eye Week 'See the Benefit' poll found that obese people were the group least likely to visit their optician. Worryingly, the survey reveals that those with a BMI in excess of 25 are most likely to believe their eyes are in a state of 'good' or 'very good' health(4).
Raman Sankaran of Simplyhealth says: "As well as lifestyle choices having an impact on eye health, the research also worryingly found that cost - or the issue of perceived cost - affects whether people attend regular sight tests. In fact 75 per cent of people admit to putting off having their eyes tested due to the price of the examination and the expense of glasses or contact lenses if needed.
"Attending a sight test needn't be expensive or act as a barrier to good eye health as there are many options available to help people budget for eyecare, such as a cash plan from Simplyhealth," Raman adds.
The Eyecare Trust recommends that everyone should have an eye examination every two years, unless advised otherwise by an optometrist. As well as providing a valuable insight into the health of your eyes a sight test also acts as an essential general health check uncovering a number of other underlying health problems such as high cholesterol, high blood pressure, diabetes and an increased risk of stroke.
For more information go to www.maculardegenerationassociation.org
Tuesday, October 27, 2009
Blue light-filtering increases macular pigment, may protect against age-related vision loss
Age-related macular degeneration, a major cause of vision loss, affects millions of older persons
Results of an important new study show that implantation of blue light-filtering intraocular lens (IOLs) at the time of cataract surgery increases a nutritional component of the eye, which may afford protection against the development and/or progression of age-related macular degeneration (AMD).
The study, conducted by leading ophthalmology and vision researchers from the Macular Pigment Research Group at the Waterford Institute of Technology, is published in the October 2009 issue of the high impact journal Investigative Ophthalmology & Visual Science (IOVS).1
AMD is a disease affecting the central part of the retina and is the leading cause of vision loss in the developed world.2 Implantation of lenses that do not filter blue light during cataract surgery has been shown to increase the risk for development and/or progression of AMD.3
"Blue light-filtering lenses filter and block damaging blue light from reaching the retina, which holds the potential of reducing vision loss and improving the quality of life for millions of older patients," said the study's chief investigator, John M. Nolan, Fulbright Scholar, BSc, PhD, deputy director, Macular Pigment Research Group, Waterford Institute of Technology, Waterford, Ireland. "These data represent an important first step in fully realizing the benefits of blue light-filtering in improving a nutritional component of the eye known as macular pigment. There is a strong scientific rationale supported by an ever-growing body of scientific evidence which suggests that macular pigment plays a role in reducing the onset and progression of AMD."
Dr. Nolan and fellow Macular Pigment Research Group researchers discovered an increase in macular pigment levels shortly after cataract surgery among the study patients who had blue light-filtering IOLs implanted.1
"Since prolonged exposure to blue light is harmful to the retina, increased levels of macular pigment are considered a strong surrogate marker for protection against the processes that cause age-related blindness, including AMD," says Dr. Nolan.
According to the study, the potential benefits associated with increased macular pigment resulting from the use of blue light-filtering lenses for prevention and/or decreased progression of AMD would be conferred at the time of cataract surgery and are expected to continue thereafter, over a patient's lifetime.1 This is especially meaningful in the modern era of cataract surgery, which is being performed annually in millions of older persons who live for many years after the procedure, as well as certain patient subgroups, who have had the surgery at an earlier age.2 The researchers note that further studies are needed to confirm the clinical benefit of their findings.1
About the Study
Dr. Nolan and colleagues conducted a prospective study in which 42 patients scheduled for cataract surgery were randomized to implantation with a blue light-filtering acrylic IOL or a standard acrylic IOL (control), with macular pigment optical density measured by a reliable method (heterochromatic flicker photometry), and serum concentrations of the macular carotenoids were quantified by a scientific procedure known as high performance liquid chromatography, prior to surgery and then at several post-procedural time points over a 1-year follow-up period.1
Cataract surgery in older persons, where the natural diseased lens (cataract) is replaced with a clear artificial IOL, has been associated with increased subsequent risk for macular disease,4 perhaps due to increased transmission of potentially injurious short-wavelength (blue) light to the retina.3
Therefore, lens manufacturers have incorporated a blue light-filter into IOLs to help reduce photo-oxidative retinal injury and thereby reduce the risk of new-onset AMD and/or its progression. Evidence suggests that photo-oxidative stress is important in the development of AMD.5 The likelihood of retinal damage is highest for short-wavelength light (blue light). Several parts of the eye, most importantly the lens, act as filters to block short-wavelength light from reaching the retina.4
Macular pigment is thought to protect against AMD because it absorbs short-wavelength (blue) light before it reaches photoreceptors in the retina and because of its antioxidant properties (decreases oxidative stress by quenching free radicals). Portions of the eye behind (posterior to) macular pigment are exposed to approximately six times the amount of blue light in persons having the lowest levels of macular pigment, as compared to those with the highest levels.5 Macular pigment is obtained entirely from the diet and transported to the retina via the blood. Therefore, ongoing research is being conducted to determine to what extent a person's diet may affect AMD. However, the data available to date is in support of such a notion.5
About Cataracts and AMD
As the aging population grows and becomes a larger percentage of the overall population, age-related diseases such as cataracts and AMD will become more prevalent.6
Surgical removal of cataracts – lens that have become clouded from buildup of protein – is the most frequently performed surgery in the U.S.7, with more than 6 million cataract surgeries currently performed each year in the U.S. and Europe combined.7,8 While vision is almost universally improved immediately following cataract removal, implantation of lens that does not filter harmful short wavelength (blue) light may hasten the progression of AMD,5 the leading cause of vision loss in people over the age of 60 in the U.S.9
AMD is a disease that affects part of the back of the eye called the macula, the central part of the retina. The central vision of affected individuals becomes blurry or wavy and can be eventually lost, which severely alters their quality of life.9,10 Approximately 25-30 million individuals are affected worldwide, with the number estimated to triple in the next 25 years.11
For more information go to www.maculardegenerationassociation.org
Results of an important new study show that implantation of blue light-filtering intraocular lens (IOLs) at the time of cataract surgery increases a nutritional component of the eye, which may afford protection against the development and/or progression of age-related macular degeneration (AMD).
The study, conducted by leading ophthalmology and vision researchers from the Macular Pigment Research Group at the Waterford Institute of Technology, is published in the October 2009 issue of the high impact journal Investigative Ophthalmology & Visual Science (IOVS).1
AMD is a disease affecting the central part of the retina and is the leading cause of vision loss in the developed world.2 Implantation of lenses that do not filter blue light during cataract surgery has been shown to increase the risk for development and/or progression of AMD.3
"Blue light-filtering lenses filter and block damaging blue light from reaching the retina, which holds the potential of reducing vision loss and improving the quality of life for millions of older patients," said the study's chief investigator, John M. Nolan, Fulbright Scholar, BSc, PhD, deputy director, Macular Pigment Research Group, Waterford Institute of Technology, Waterford, Ireland. "These data represent an important first step in fully realizing the benefits of blue light-filtering in improving a nutritional component of the eye known as macular pigment. There is a strong scientific rationale supported by an ever-growing body of scientific evidence which suggests that macular pigment plays a role in reducing the onset and progression of AMD."
Dr. Nolan and fellow Macular Pigment Research Group researchers discovered an increase in macular pigment levels shortly after cataract surgery among the study patients who had blue light-filtering IOLs implanted.1
"Since prolonged exposure to blue light is harmful to the retina, increased levels of macular pigment are considered a strong surrogate marker for protection against the processes that cause age-related blindness, including AMD," says Dr. Nolan.
According to the study, the potential benefits associated with increased macular pigment resulting from the use of blue light-filtering lenses for prevention and/or decreased progression of AMD would be conferred at the time of cataract surgery and are expected to continue thereafter, over a patient's lifetime.1 This is especially meaningful in the modern era of cataract surgery, which is being performed annually in millions of older persons who live for many years after the procedure, as well as certain patient subgroups, who have had the surgery at an earlier age.2 The researchers note that further studies are needed to confirm the clinical benefit of their findings.1
About the Study
Dr. Nolan and colleagues conducted a prospective study in which 42 patients scheduled for cataract surgery were randomized to implantation with a blue light-filtering acrylic IOL or a standard acrylic IOL (control), with macular pigment optical density measured by a reliable method (heterochromatic flicker photometry), and serum concentrations of the macular carotenoids were quantified by a scientific procedure known as high performance liquid chromatography, prior to surgery and then at several post-procedural time points over a 1-year follow-up period.1
Cataract surgery in older persons, where the natural diseased lens (cataract) is replaced with a clear artificial IOL, has been associated with increased subsequent risk for macular disease,4 perhaps due to increased transmission of potentially injurious short-wavelength (blue) light to the retina.3
Therefore, lens manufacturers have incorporated a blue light-filter into IOLs to help reduce photo-oxidative retinal injury and thereby reduce the risk of new-onset AMD and/or its progression. Evidence suggests that photo-oxidative stress is important in the development of AMD.5 The likelihood of retinal damage is highest for short-wavelength light (blue light). Several parts of the eye, most importantly the lens, act as filters to block short-wavelength light from reaching the retina.4
Macular pigment is thought to protect against AMD because it absorbs short-wavelength (blue) light before it reaches photoreceptors in the retina and because of its antioxidant properties (decreases oxidative stress by quenching free radicals). Portions of the eye behind (posterior to) macular pigment are exposed to approximately six times the amount of blue light in persons having the lowest levels of macular pigment, as compared to those with the highest levels.5 Macular pigment is obtained entirely from the diet and transported to the retina via the blood. Therefore, ongoing research is being conducted to determine to what extent a person's diet may affect AMD. However, the data available to date is in support of such a notion.5
About Cataracts and AMD
As the aging population grows and becomes a larger percentage of the overall population, age-related diseases such as cataracts and AMD will become more prevalent.6
Surgical removal of cataracts – lens that have become clouded from buildup of protein – is the most frequently performed surgery in the U.S.7, with more than 6 million cataract surgeries currently performed each year in the U.S. and Europe combined.7,8 While vision is almost universally improved immediately following cataract removal, implantation of lens that does not filter harmful short wavelength (blue) light may hasten the progression of AMD,5 the leading cause of vision loss in people over the age of 60 in the U.S.9
AMD is a disease that affects part of the back of the eye called the macula, the central part of the retina. The central vision of affected individuals becomes blurry or wavy and can be eventually lost, which severely alters their quality of life.9,10 Approximately 25-30 million individuals are affected worldwide, with the number estimated to triple in the next 25 years.11
For more information go to www.maculardegenerationassociation.org
Thursday, October 22, 2009
NeoVista®, Inc. Completes Enrollment in Pivotal CABERNET™ Study
Neovascular AMD affects hundreds of thousands of patients globally. It is our hope that upon one-year follow-up, the data will support FDA approval in a most timely manner so that retinal surgeons, patients, and heath care systems in the US and around the world will have a cost effective option available for treating this dreadful disease in the immediate future.
NeoVista, Inc. today announced the completion of enrollment in its global 450-patient randomized controlled study of their revolutionary epimacular brachytherapy procedure for the treatment of neovascular age-related macular degeneration (AMD). The Company will now begin the mandated one-year data follow-up before submitting the final clinical module of its Pre-Market Approval (PMA) submission to the FDA.
"It's exciting to reach this long anticipated milestone in the CABERNET Study," said John N. Hendrick, President and CEO of NeoVista. "Neovascular AMD affects hundreds of thousands of patients globally. It is our hope that upon one-year follow-up, the data will support FDA approval in a most timely manner so that retinal surgeons, patients, and heath care systems in the US and around the world will have a cost effective option available for treating this dreadful disease in the immediate future."
The largest study of its kind to date, the multi-center CABERNET (CNV Secondary AMD Treated with BEta RadiatioN Epiretinal Therapy) Study assigned patients into one of two arms: a control arm where patients were administered regular Lucentis® (Genentech, South San Francisco, CA) injections and a one time surgical arm, where patients were administered a dose of strontium-90 beta radiation via a short surgical procedure, followed by concomitant injections of Lucentis when needed. The primary efficacy endpoint for the CABERNET Study is based on one-year follow-up of the surgical arm cohort when compared to the control group.
"The CABERNET Study has brought together multi-disciplinary clinical teams aligned around the mission of addressing the serious problem of neovascular AMD," said Pravin U Dugel, Managing Partner, Retinal Consultants of Arizona, Phoenix, Arizona and principal investigator for the CABERNET Study. "I look forward to the final results of this ambitious clinical trial. More than any other recent trial, this clinical trial has the potential of improving the quality of life and the overall treatment of patients with neovascular AMD. It could potentially have a significant impact on the practice patterns and economics of retinal physicians as well as global health care systems."
For more information go to www.maculardegenerationassociation.org
NeoVista, Inc. today announced the completion of enrollment in its global 450-patient randomized controlled study of their revolutionary epimacular brachytherapy procedure for the treatment of neovascular age-related macular degeneration (AMD). The Company will now begin the mandated one-year data follow-up before submitting the final clinical module of its Pre-Market Approval (PMA) submission to the FDA.
"It's exciting to reach this long anticipated milestone in the CABERNET Study," said John N. Hendrick, President and CEO of NeoVista. "Neovascular AMD affects hundreds of thousands of patients globally. It is our hope that upon one-year follow-up, the data will support FDA approval in a most timely manner so that retinal surgeons, patients, and heath care systems in the US and around the world will have a cost effective option available for treating this dreadful disease in the immediate future."
The largest study of its kind to date, the multi-center CABERNET (CNV Secondary AMD Treated with BEta RadiatioN Epiretinal Therapy) Study assigned patients into one of two arms: a control arm where patients were administered regular Lucentis® (Genentech, South San Francisco, CA) injections and a one time surgical arm, where patients were administered a dose of strontium-90 beta radiation via a short surgical procedure, followed by concomitant injections of Lucentis when needed. The primary efficacy endpoint for the CABERNET Study is based on one-year follow-up of the surgical arm cohort when compared to the control group.
"The CABERNET Study has brought together multi-disciplinary clinical teams aligned around the mission of addressing the serious problem of neovascular AMD," said Pravin U Dugel, Managing Partner, Retinal Consultants of Arizona, Phoenix, Arizona and principal investigator for the CABERNET Study. "I look forward to the final results of this ambitious clinical trial. More than any other recent trial, this clinical trial has the potential of improving the quality of life and the overall treatment of patients with neovascular AMD. It could potentially have a significant impact on the practice patterns and economics of retinal physicians as well as global health care systems."
For more information go to www.maculardegenerationassociation.org
Tuesday, October 13, 2009
Signs Of Macular Degeneration May Predict Heart Disease
A large study found strong evidence that older people who have age-related macular degeneration (AMD) are at increased risk for coronary heart disease (CHD), although not for stroke. This result adds to mounting evidence that AMD and cardiovascular disease may share some risk factors--smoking, high blood pressure, inflammatory indicators such as C-reactive protein, genetic variants such as complement factor H--and disease mechanisms.
For more information go to www.maculardegenerationassociation.org
For more information go to www.maculardegenerationassociation.org
Monday, October 5, 2009
Patent-pending process improves eye disease detection
Memphis Business Journal - by Michael Sheffield
A collaboration between two professors at the University of Memphis and Southern College of Optometry could result in earlier detection of retinal diseases through a patent-pending testing process.
The Pseudo 2D Fractal Analysis was developed through a collaboration between Khan Iftekharuddin, associate professor in the Department of Electrical and Computer Engineering at the University of Memphis, and Pinakin Gunvant, assistant professor at Southern College of Optometry.
The process uses light beamed through the back of the retina to measure the thickness of retinal tissue at certain points. If the tissue is thick at the “12 and six o’clock” points, it is an indicator of glaucoma. The reflection of the light provides an indicator of the tissue’s thickness.
Gunvant says previous testing methods were accurate 85% of the time, but the 2D method has proven to be 98% accurate.
“That’s very clinically significant,” Gunvant says. “But you’re not inventing new devices. You’re just analyzing the data better.”
Gunvant and Iftekharuddin were doing separate research, with Gunvant focusing on retinal research at the Southern College and Iftekharuddin doing imaging work at the U of M. Gunvant said neither of the two had any idea the other existed until he looked Iftekharuddin up online. Ironically, the U of M professor was out of the country when Gunvant first contacted him.
“I found him through my good friend, Google, and he was right down the road,” Gunvant says. “If it wasn’t for technology, we might have never met.”
Iftekharuddin had used imaging to detect brain tumors through work with St. Jude Children’s Research Hospital, but hadn’t done any research with glaucoma. He says fractal imaging is able to pick up any irregularities in shapes or signals.
“We just took that and applied it to glaucoma and the results turned out to be excellent,” Iftekharuddin says. “Like any other disease, if you diagnose early you can treat it better.”
Once the two professors ensured the technique worked, the University of Memphis began the patent process, which can take up to three years. But it could also yield a viable product for the school to market and license, says Kevin Boggs, director of technology transfer and research development at the University of Memphis.
Boggs says the length of the patent process won’t prevent the two schools from marketing the product to companies that have a history of licensing patent applications.
“Once they’re familiar with the product, they’ll invest in it knowing the odds of getting a patent,” Boggs says. “There are a couple of options. We could either go with an exclusive or non-exclusive license, but we’d have to look at what would bring the product to the broadest possible market to help the most people.”
Gunvant says the technique could also detect other causes of blindness, like diabetes or macular degeneration. The immediate focus, however, is glaucoma, which is the second-leading cause of blindness in the world and the leading cause of blindness among African-Americans.
Gunvant says the new focus of the research will be trying to reach 100% accuracy.
“I doubt we’ll ever hit 100%, but most scientists get proven wrong in 15 years,” Gunvant says. “Glaucoma is very variable and affects different individuals in different ways. We’d have to do a very large scale study to get better than where we are at the moment.”
Gunvant says the technique probably would not have been perfected without the team effort.
“It’s hard to be an expert in every field, so multi-disciplined collaboration is required,” he says. “When you look at a problem from one angle, your brain gets fried, so you have to have someone else to come in and help you solve it.”
For more information go to www.maculardegenerationassociation.org
A collaboration between two professors at the University of Memphis and Southern College of Optometry could result in earlier detection of retinal diseases through a patent-pending testing process.
The Pseudo 2D Fractal Analysis was developed through a collaboration between Khan Iftekharuddin, associate professor in the Department of Electrical and Computer Engineering at the University of Memphis, and Pinakin Gunvant, assistant professor at Southern College of Optometry.
The process uses light beamed through the back of the retina to measure the thickness of retinal tissue at certain points. If the tissue is thick at the “12 and six o’clock” points, it is an indicator of glaucoma. The reflection of the light provides an indicator of the tissue’s thickness.
Gunvant says previous testing methods were accurate 85% of the time, but the 2D method has proven to be 98% accurate.
“That’s very clinically significant,” Gunvant says. “But you’re not inventing new devices. You’re just analyzing the data better.”
Gunvant and Iftekharuddin were doing separate research, with Gunvant focusing on retinal research at the Southern College and Iftekharuddin doing imaging work at the U of M. Gunvant said neither of the two had any idea the other existed until he looked Iftekharuddin up online. Ironically, the U of M professor was out of the country when Gunvant first contacted him.
“I found him through my good friend, Google, and he was right down the road,” Gunvant says. “If it wasn’t for technology, we might have never met.”
Iftekharuddin had used imaging to detect brain tumors through work with St. Jude Children’s Research Hospital, but hadn’t done any research with glaucoma. He says fractal imaging is able to pick up any irregularities in shapes or signals.
“We just took that and applied it to glaucoma and the results turned out to be excellent,” Iftekharuddin says. “Like any other disease, if you diagnose early you can treat it better.”
Once the two professors ensured the technique worked, the University of Memphis began the patent process, which can take up to three years. But it could also yield a viable product for the school to market and license, says Kevin Boggs, director of technology transfer and research development at the University of Memphis.
Boggs says the length of the patent process won’t prevent the two schools from marketing the product to companies that have a history of licensing patent applications.
“Once they’re familiar with the product, they’ll invest in it knowing the odds of getting a patent,” Boggs says. “There are a couple of options. We could either go with an exclusive or non-exclusive license, but we’d have to look at what would bring the product to the broadest possible market to help the most people.”
Gunvant says the technique could also detect other causes of blindness, like diabetes or macular degeneration. The immediate focus, however, is glaucoma, which is the second-leading cause of blindness in the world and the leading cause of blindness among African-Americans.
Gunvant says the new focus of the research will be trying to reach 100% accuracy.
“I doubt we’ll ever hit 100%, but most scientists get proven wrong in 15 years,” Gunvant says. “Glaucoma is very variable and affects different individuals in different ways. We’d have to do a very large scale study to get better than where we are at the moment.”
Gunvant says the technique probably would not have been perfected without the team effort.
“It’s hard to be an expert in every field, so multi-disciplined collaboration is required,” he says. “When you look at a problem from one angle, your brain gets fried, so you have to have someone else to come in and help you solve it.”
For more information go to www.maculardegenerationassociation.org
Friday, September 25, 2009
Retinal implant could help the blind see
By Emma Woollacott
MIT researchers are working on a retinal implant that could help blind people regain a useful level of vision.
It's designed for sufferers of retinitis pigmentosa and age-related macular degeneration, two of the leading causes of blindness. It won't restore normal vision, but could help blind people get around more easily.
Patients would wear a pair of glasses with a camera that sends images to a microchip attached to the eyeball. The glasses contain a coil that wirelessly transmits power to receiving coils surrounding the eyeball.
When the microchip receives visual information, it activates electrodes that stimulate nerve cells in the areas of the retina corresponding to the features of the visual scene. The electrodes directly activate optical nerves that carry signals to the brain, bypassing the damaged layers of retina.
In previous implants, the electrodes were attached directly to the retina from inside the eye, which carries more risk of damage. In the latest version, the implant is attached to the outside of the eye, and the electrodes are implanted behind the retina.
The team has been working on the implant for 20 years, and hopes to start testing it in blind patients within the next three years. The goal is to produce a chip that can be implanted for at least 10 years.
They've tried it out in Yucatan miniature pigs, which have roughly the same sized eyeballs as humans, purely to determine whether the implants remain functional and safe. So far, the prototypes have been successfully implanted in pigs for up to 10 months.
The researchers hope that once human trials begin and blind patients can offer feedback on what they're seeing, they will learn much more about how to configure the algorithm implemented by the chip to produce useful vision.
Patients have said that what they would like most is the ability to recognize faces. "If they can recognize faces of people in a room, that brings them into the social environment as opposed to sitting there waiting for someone to talk to them," says Shawn Kelly, a researcher in MIT's Research Laboratory for Electronics.
For more information go to www.maculardegenerationassociation.org
MIT researchers are working on a retinal implant that could help blind people regain a useful level of vision.
It's designed for sufferers of retinitis pigmentosa and age-related macular degeneration, two of the leading causes of blindness. It won't restore normal vision, but could help blind people get around more easily.
Patients would wear a pair of glasses with a camera that sends images to a microchip attached to the eyeball. The glasses contain a coil that wirelessly transmits power to receiving coils surrounding the eyeball.
When the microchip receives visual information, it activates electrodes that stimulate nerve cells in the areas of the retina corresponding to the features of the visual scene. The electrodes directly activate optical nerves that carry signals to the brain, bypassing the damaged layers of retina.
In previous implants, the electrodes were attached directly to the retina from inside the eye, which carries more risk of damage. In the latest version, the implant is attached to the outside of the eye, and the electrodes are implanted behind the retina.
The team has been working on the implant for 20 years, and hopes to start testing it in blind patients within the next three years. The goal is to produce a chip that can be implanted for at least 10 years.
They've tried it out in Yucatan miniature pigs, which have roughly the same sized eyeballs as humans, purely to determine whether the implants remain functional and safe. So far, the prototypes have been successfully implanted in pigs for up to 10 months.
The researchers hope that once human trials begin and blind patients can offer feedback on what they're seeing, they will learn much more about how to configure the algorithm implemented by the chip to produce useful vision.
Patients have said that what they would like most is the ability to recognize faces. "If they can recognize faces of people in a room, that brings them into the social environment as opposed to sitting there waiting for someone to talk to them," says Shawn Kelly, a researcher in MIT's Research Laboratory for Electronics.
For more information go to www.maculardegenerationassociation.org
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