This following article was in the December 2014 issue of RODS, the quarterly journal of Retina Australia (NSW). If you would like to become a subscriber to the journal contact: email@example.com
RETINA AUSTRALIA (NSW) INC
In some respects, this has been an uneventful year for RA (NSW). While the Council has worked steadily in their voluntary capacity to ensure the continuity of the organization, things are changing in the sphere of voluntary commitment. Not only RA (NSW) but all the state bodies of Retina Australia are experiencing difficulties in recruiting individuals competent and willing to take on a major role, roles which are becoming more complex and demanding of time than they were in earlier years. Therefore, long-standing office bearers continue to accept nomination, having what young people now refer to as a passionate commitment to our cause.
Having said that our two newer members of the Council have organized major fund-raising events during the year: Debra Hescott put on an amazing ‘Dining in the Dark’ event in Newcastle, raising $2,600. Leanne Calthorpe, with the experienced assistance of Robyn Richards, organized a delightful “1920’sevening of jazz” at Luna Park which raised well over $6,000. At this event, we were presented with a $1,500 cheque from Yates Australia and we also heard from one of our best speakers ever: Dr Richard Smith, documentary maker, who gave his time freely. We rely on the council members and their friends and our long-standing supporters from the public for these events as only a few members attend.
Those of us, serving on the RANSW Council value very much those members who constantly show their support, both by donating to our cause and by attending our annual meeting. Members were once again generous in responding to our annual “tax appeal” letter and we thank them all. Once again, we thank Nino and Elese Gatto of Griffith whose regular street stalls have raised a significant amount over the year. This year, in May we received a cheque for $7,000 from the Masonic Order of the Amaranth, and we are very grateful to them for having chosen RANSW as their charity for 2013/14.
Our strongest work has been in the area of peer support, with members of our council giving a lot of their time to speak to people newly diagnosed or who have a relative or friend in that situation. We continue to send our information packages to these people but are noticing a diminishing willingness to take up membership offered therein. Others often tend to take up membership and then fall away, probably turning their attention to other commitments and neglecting to pay an annual subscription to RODS journal. We do not lose contact with any of these people as membership is a lifetime one, and they do get notice of our AGM and its associated lunch.
Robert Craft took over the position of editor of RODS and has continued in this, notwithstanding his work commitments. We continued to market our owl merchandise in conjunction with World Retina Day and Hayfee worked on this, sending out boxes for the counters of the HCF offices and many optometrists, and some individual supporters, whom she contacted. Kerrie has been our absolute mainstay and we value very much her work along with Hayfee in our office on Wednesdays. Robyn organized media releases for World Retina Day along with ‘dub sats’ for TV. These are sometimes shown all over Australia but mostly late at night.
Having noticed the relatively low response from NSW families contributing blood samples to the Australian Inherited Retinal Disease Register and DNA bank, this year we wrote to every optometrist in NSW promoting participation from their clients who have an inherited retinal dystrophy.
Another promotional activity we have undertaken is to design and produce donation envelopes similar to those now being used by major charities to facilitate donations from the public, particularly at events where they can be handed out. We urge you to contact us for a supply if you can place them where there could be donors, as we need to have financial support to continue our work. This year we once again contributed substantially to the Retina Australia research effort and the Australian Inherited Retinal Disease Register, calling on our reserves to do so.
Finally, a note of thanks to everyone who has helped RANSW to continue to be a healthy and very necessary support for people with a retinal dystrophy and most importantly to raise funds to encourage researchers to find a cure or treatment. Thank you Don and Marea Burke, Yates Australia, Bruce Richards, Diane Deggens, and those who work willingly on the council: Secretary Robyn, our valued treasurer Andrew, Robert, Leanne and Debra.
From all of our committee along with myself, we would like to wish all of members a safe and happy Christmas and we look forward to your continued support into 2015.
There is a new short movie doing the rounds: “ Beyond Sight”
Blind Brazilian Surfer Derek Rabelo, 20, underwent a three year journey to prepare himself mentally, physically and spiritually to achieve his dream to surf the famous Banzai Pipeline on Hawaii’s North Shore.
“Beyond Sight” is the name of the film which has been made documenting this journey. Rabelo said he was always fascinated by the sounds of the waves and the feelings of the ocean.
The film features surfers such as Kelly Slater, Tom Curren, Laird Hamilton, Rob Machado, Mike Stewart, Lake Peterson and Derek Ho and how these individuals assisted Rabelo in his quest to conquer the world’s ultimate wave.
Every one of these surfers is the cream of the surfing world.
“Pipeline is one of the most dangerous waves in the world” Laird Hamilton said. “And when you know what you’re doing and have perfectly good eyes, you can die. When Derek went out to Pipeline and surfed , the angels were busy that day”.
To a surfer a Pipeline is as dangerous as it gets, and is like the Everest of surfing. It is a short and very steep wave with unbelievable power.
For a guy who was born blind to achieve this is remarkable.
Google Beyond Sight and watch or listen to the trailer – it’s inspirational.
Date: October 31, 2014
Source: Harvard University
A team of researchers has developed a system that uses commercially-available molecules called cationic lipids -- long, greasy molecules that carry a positive charge -- to efficiently deliver genome-editing proteins into cells, and have even demonstrated that the technology can be used to perform genome editing in living animals.
As potential next-generation therapeutics and research tools, few life sciences technologies hold more promise than genome-editing proteins -- molecules that can be programmed to alter specific genes in order to treat or even cure genetic diseases.
There's at least one catch though -- getting genome-editing proteins into cells, where they need to be to access the genome, is a major challenge, especially in live animals or human patients.
Conventionally, researchers have delivered the DNA encoding these genome-editing proteins into cells and then relied on the cells to produce the corresponding genome-editing proteins. But many DNA delivery strategies cannot be used in animals or human patients. Other DNA delivery strategies such as infecting with viruses that inject DNA into cells can raise complicating long-term safety issues, especially when the editing of the human genome is involved.
What may be more promising, the new study finds, is the direct delivery of genome-editing proteins into cells, rather than delivery of the corresponding genes that encode these proteins. And a class of molecules that can open the door for genome-editing proteins, as it turns out, is probably already on the shelves of many biologists.
Led by Professor of Chemistry and Chemical Biology David Liu and his group members Drs. John Zuris and David Thompson, a team of Harvard researchers has developed a system that uses commercially-available molecules called cationic lipids -- essentially long, greasy molecules that carry a positive charge at one end -- to efficiently introduce genome-editing proteins into cells, and have even demonstrated that the technology can be used to modify genes in living animals. The study is described in an October 30 paper in Nature Biotechnology.
"Current drugs that treat genetic diseases cannot address the root cause of the disease," Liu explained. "Unlike infectious diseases, for example, which we treat by killing the disease-causing agent, in the case of diseases that come from mutations in our own genes, one has to go into the cells and do surgery on our genomes to fix the root cause. Thanks to recent discoveries by scientists around the world, we now have genome-editing proteins that can do the surgery. But the challenge is that these proteins, like virtually all proteins, do not enter cells spontaneously”.
"In this study we describe a method to very potently deliver genome-editing proteins into cells," Liu added. "And we observed efficient genome modification using this method not just in cultured cells, but also in living animals."
Though he warned that no system, including this one, will be a one-size-fits-all delivery solution, Liu believes that delivering genome-editing proteins into cells could offer hope to patients suffering from a host of conditions, including certain diseases of the eye, ear, liver, muscles, and blood.
One condition that's already in researchers' crosshairs is deafness.
Working with Zheng-Yi Chen, an Associate Professor of Otology and Laryngology at Harvard Medical School and researcher at Massachusetts Eye and Ear Infirmary, Liu and colleagues used the newly-developed system to modify genes in specialized "hair cells" in the inner ear of mice. Hair cell damage, either from environmental or genetic factors, is a common cause of hearing loss.
A common strategy for introducing proteins into cells, Liu said, has been to rely on positively charged proteins. Because the exterior of mammalian cells are decorated with negatively charged molecules, positively charged proteins are stick to them, causing them to be engulfed by cells in compartments called endosomes. Liu and his students previously developed one such strategy that uses positively "supercharged" proteins as delivery vehicles.
"The key difficulty, which has been known for decades, is that getting cargo out of endosomes is very difficult," Liu said. "The efficiency with which a protein will spontaneously escape an endosome is very low -- maybe as low as one-in-a-million under normal circumstances."
To develop a system that would allow for the more efficient delivery of proteins into cells, Liu and colleagues took the opposite approach, one that involved mimicking the way scientists deliver nucleic acids like DNA and RNA into cells.
That system relies on positively charged molecules called cationic lipids, which bind with negatively charged nucleic acids to form structures called liposomes. Once formed, there are at least two ways for liposomes to deliver their contents into a cell. In some cases, Liu explained, the liposome may fuse with the cell's membrane, releasing its cargo. Alternately, the liposome may be taken in as an endosome, and then release its contents if the liposome and endosome membranes fuse.
"We had the very simple idea to use the same commercially-available cationic lipids researchers use to deliver DNA and RNA to deliver proteins. But instead of using super-positively charged proteins, we use super-negatively charged proteins, which resemble nucleic acids in their highly negatively charged state." Liu said. "The potency of delivering proteins that are associated with highly negatively charged molecules using cationic lipids is approximately 1,000 times greater than delivering proteins using positively charged proteins or peptides."
Importantly, the team's experiments showed that the new system, when applied to the delivery of genome editing proteins, results in target gene modification that is at least as efficient as the best results they observed from the delivery of DNA encoding genome-editing proteins. But Liu and co-workers showed that the specificity of genome editing -- how accurately the targeted genes are modified versus modification of other sites in the human genome -- was much higher from protein delivery instead of DNA delivery.
This outcome was what the researchers hoped to see. "Following DNA delivery, the encoded proteins can be expressed in difficult-to-regulate amounts for long periods of time," Liu said. "There has always been a mismatch between DNA delivery and the desired outcome of genome editing. In genome editing, the mission is to fix one or two copies of a gene. After a genome-editing protein finishes that mission, you want it to go away, because the only things it can do after that point are undesired and possibly harmful. "So protein delivery, which is transient and short-lived, seemed to be a better match than DNA delivery for most genome-editing applications."
Ultimately, Liu believes genome-editing proteins may serve as the next generation of therapies for a host of disorders that have been difficult to treat.
"We hope this approach to protein delivery will help connect where genome editing is now to where the field needs to be in order to realize the therapeutic potential of these proteins to address genetic diseases," Liu said.
Date: October 31, 2014
Source: University of Lincoln
A new computer game is being tested that researchers hope could hold the key to helping visually-impaired children lead independent lives. Developed by a team of neuroscientists and video game designers, the Eyelander game features exploding volcanoes, a travelling avatar and animated landscapes. The idea is to improve the functional vision of children who have sight issues due to a brain injury rather than damage to the eye itself.
Researchers are to begin testing a new computer game which they hope could hold the key to helping visually-impaired children lead independent lives. Developed by a team of neuroscientists and video game designers from the University of Lincoln, UK, and the WESC Foundation, one of the UK's leading specialist schools for visually impaired children, the Eyelander game features exploding volcanoes, a travelling avatar and animated landscapes.
The idea is to improve the functional vision of children who have sight issues due to a brain injury rather than damage to the eye itself. Functional vision is used to perform everyday tasks such as safely crossing the road or finding a book on a bookshelf, but when the visual pathways between the brain and the eyes become damaged, the messages aren't correctly relayed and the visual field becomes reduced.
There are around 25,000 blind and partially-sited children in the United Kingdom -- equating to two children per 1,000. The causes of blindness in children are varied, but cerebral visual impairment (damage to areas of the brain associated with vision) is among the most common.
Computational neuroscientist Jonathan Waddington is conducting the trials of Eyelander at WESC, overseen by Timothy Hodgson, Professor of Cognitive Neuroscience and Head of the School of Psychology at the University of Lincoln and Dr Conor Linehan, a specialist in computer game development based in Lincoln's School of Computer Science.
Jonathan said: "What we are aiming to do is improve the patient's functional vision, which is needed to perform tasks of independent living. We are tapping into the brain's innate ability to adapt (also known as neuroplasticity), and because substantial changes in vision are possible even into adulthood, this could yield real results.
"The game draws on existing training programs, which only offer black and white, two-dimensional shapes, and no interaction. The key to making the game successful is that we have we have combined our knowledge of neuroscience and psychology with expertise in game development so it is both effective and engaging. "Clinical trials will get under way this summer to evaluate whether the software could become a valuable new tool for the treatment of children and young adults with visual impairments."
Gamers begin by helping the main character, Eyelander, safely escape an erupting volcanic island. The animated character then has to navigate a series of obstacles across 12 levels, ranging from a stampede of angry cows and an oversized baby, to a UFO and a naughty panda. The scenes change and include an enchanted forest, a swamp owned by a friendly alligator called Barry, a fairground, and a secret laboratory.
In the early levels, players must find a shape on the screen which is surrounded by a group of similar 'distracting' shapes, and track its movement. As the game progresses, multiple colours and more distracting shapes are introduced. The game also features advanced options to adapt the difficulty to the specific cognitive and visual impairment of the person playing, such as changing the size or number of shapes, and the amount of time the player has to complete each level.
During the clinical trial phase visually-impaired children and young adults from ages eight to 25 will have the game installed on a home computer and complete the tasks in their own time to emulate the environment in which the software would be used. Professor Hodgson said: "Research has already shown that this type of training can lead to significant recovery of sight following damage to visual centres of the brain in adults, so it is vital that those using it are motivated by something interesting and engaging."
A video outlines the game: http://youtube/DPXDH1pfstw
Our AGM and lunch on 8th November was a really enjoyable occasion. The highlight was our speaker Josh Guest Managing Director of his company b2Cloud who came up from Victoria in response to our invitation to tell us about the amazing technology in the process of development that will be life-changing for those of us with a visual impairment, and in fact for the community as a whole. We heard about all sorts of apps in the pipeline, including “Google Glass”, a tiny computer worn on glasses that will tell us verbally just about anything we want to know, which of course is often just what object or information is in front of us. We heard about watches worn on the wrist that will do just about the same, including setting up a vibration in a retail store that will bring help immediately if needed or just simply take us to what we want to look at. This retail service is already in action in some stores and most will implement it. All in all, Josh’s talk had us all fascinated and excited about options for the very near future. Josh reported that in consideration of people’s needs in the early stages, they realised that what would benefit those with low vision or hearing would be of benefit to all, so things are advancing on that premise.
While we were disappointed at having lost our longstanding venue, The ‘Mezz’ Restaurant which has now closed, we found the staff at the City of Sydney RSL most obliging and the lunch prepared by Joe’s Kitchen was excellent.
In their usual quiet way of helping our cause, Reg and Margaret McBride surprised our Treasurer by taking up the $590 bill, so that the profit from the event was substantial. Thanks Margaret and Reg for your valued donation.
A new Council for 2015 was elected and councillors’ names appear on the back cover. We welcome Fleur Henderson and Bruce Richards to the Council.
Donations envelopes - We’ve prepared envelopes for promoting an easy way to donate. These are ideal for occasions where it is asked that people not give a gift or flowers, but donate to a charity instead. If you or someone you know is involved in such an occasion, a supply of these can be posted to you by calling the office on 9744 7738.
The aim of this project is to establish a comprehensive Australian Inherited Retinal Disease (AIRD) Register and DNA Bank, and to progressively analyse stored DNA samples in an attempt to identify IRD-causing mutations.
As the project progresses, the list of individuals within Australia for whom disease causing mutations have been identified will grow. The well-considered conduct of this project will therefore place Australians affected by specific IRDs in an enviable position for taking advantage of gene specific treatments as they continue to emerge over the coming years.
All DNA samples and results of genetic analyses (where known) are shown on the web site www.scgh.health.wa.gov.au/Research/InheritedRetinal.html (without identifying information). This web site is updated every 3 months, and the number of DNA samples listed is steadily growing to thousands. These DNA samples may be made available to other approved research groups who wish to carry out and report back on IRD targeted studies, thereby increasing the power of this resource. However, under no circumstances will participants identifying information be provided to other research groups.
This project may also lead to informed genetic counselling for some participants.
Have you and your family registered with the Australian Inherited Retinal Disease Register and DNA Bank? If you have NOT sent DNA samples from the affected person and family members then please do not hesitate to contact:-
Tina Lamey – Senior Research Officer
Phone : 08 9346 3586 or email firstname.lastname@example.org
THE KNFB READER for YOUR iPhone
The highly anticipated KNFB Reader
converts printed text into high quality speech to provide accurate,
fast, and efficient access to both single and multiple page documents
with the tap of a button on the iPhone. Picture accuracy is facilitated
by a Field of View Report, Automatic Page Detection, and Tilt Control.
Our app allows users to capture pictures of virtually any type of
printed text, including mail, receipts, class handouts, memos and many
other documents that you may encounter. Proprietary document analysis
technology determines the words and reads them aloud to the user with
high quality text-to-speech and Braille access. Individuals with print
disabilities will benefit from the synchronized speech and text
highlighting capabilities. KNFB Reader will revolutionize access to
print materials for the mobile professional and busy student by
providing advanced state of the art mobile reading technology in a
single hand-held device.
By harnessing the power of digital photography coupled with state of the art Apple hardware, this new app, tailored to the specific needs of people who are blind or visually impaired, makes access to print materials much faster and more efficient than ever. This fabulous, life-changing technology was presented by James Gashel, Vice President of Business and more efficient than ever. This fabulous, life-changing technology was presented by James Gashel, Vice President of Business Development at K–NFB Reading Technology Inc. and Secretary of the National Federation of the Blind, during the General Session of the Convention, before a presentation of Ray Kurzweil, Director of Engineering at Google Inc. The KNFB Reader for iOS is a joint development effort of Sensotec nv and K–NFB Reading Technology Inc.
The KNFB Reader app may be purchased and downloaded by navigating to the following link. KNFB Reader for iOS.
Date: October 20, 2014
Source: University of Pennsylvania School of Medicine
Blue light can both set the mood and set in motion important biological responses. Researchers at the University of Pennsylvania's School of Medicine and School of Arts and Sciences have teased apart the separate biological responses of the human eye to blue light, revealing an unexpected contest for control. Their work addresses the properties of melanopsin, a light-sensitive protein in the eye that establishes the rhythm of our day-night cycle and the familiar constriction of the pupil to bright light. They measured the pupil response to stimulation of melanopsin and of short-wave-sensitive (S) cones, the other blue light-sensing cells that operate in daylight. Surprisingly, they found that melanopsin and S-cones have opposite effects and compete for control of the pupil in blue light. Their complete results are published in the current issue of PNAS.
Drs. Aguirre and Brainard and graduate student Spitschan found that melanopsin, a protein and short wave-sensitive S-cones, both in the retina have opposite effects and compete for control of the pupil in response to blue light.
"The challenge of studying melanopsin is that it is very sensitive to blue light, a short-wave light emitted by digital devices including smartphones, tablets, and computers, as are S-cones," says lead author, Manuel Spitschan, a Penn graduate student in psychology. "Previous studies in the human eye have not separately studied the S-cones and melanopsin because flashing a blue light stimulates both of these cells, so we didn't know if what a person saw or the response of the pupil was from one or both." To overcome this problem, the Penn team developed a special class of visual stimuli: they produced flickering light that stimulates melanopsin but is invisible to S-cones, and a second flickering light that stimulates S-cones but is invisible to melanopsin. The lights were created using a machine that can sculpt and switch between computer-designed rainbows of light.
The researchers had 16 people watch this flickering light while the response of their pupil was recorded. The light that stimulates melanopsin made the pupil slowly contract. To their surprise, they also discovered that stimulation of S-cones made the pupil get larger. That is, when the S-cones of the eye captured more light, the pupil enlarged, the opposite of what is generally thought of as the natural pupil response. This means that blue light sets off a tug-of-war between melanopsin and S-cones to make your pupil smaller or bigger. The melanopsin effect is stronger, resulting in the familiar shrinking of the pupil to bright light of any colour.
"For the first time in people we are able to probe the relationship between melanopsin signals and the cones and how they work together or in opposition," says David Brainard, PhD, RRL professor of Psychology, director of the Vision Research Center and director of the Institute for Research in Cognitive Science. And what do these special flickering lights look like? "The flicker that stimulates S-cones looks like it is switching between a bluish and yellowish colour. The flicker that stimulates melanopsin, however, is hard to see, and looks like a soft glow that rises and falls in brightness."
Light enters the human eye and is imaged on the retina. It has long been know that the retinal image is sensed by neurons known as the rods and cones. The rods operate in dim light levels and allow us to see at night. It is the signals from rods and cones that the brain converts into the images we see. Recently, though, another class of retinal cells has been identified that also senses light. These cells are known as intrinsically photosensitive ganglion cells, and they contain the protein melanopsin. Melanopsin is sensitive to light at wavelengths intermediate to those sensed by the S and M cones. It appears that it primarily mediates light-driven functions other than conscious vision, such as setting our circadian clock and contributing to control of the pupil.
The work of the Penn team makes it possible to isolate and study the properties of melanopsin in people, separate from the cone cells. We can now ask what we "see" with melanopsin.
"This is important because we think melanopsin could be involved in clinical conditions," says Geoffrey K. Aguirre, MD, PhD, a behavioral neurologist and associate professor in the department of Neurology. "For example, it seems that too much stimulation of melanopsin produces the feeling of pain from light that is too bright, and not having enough melanopsin stimulation may be part of seasonal affective disorder, in which people become depressed when they don't have enough light exposure. Having now teased apart the melanopsin and cone responses to blue light, we can study how the eye is involved in these disorders."
A patent on this alternative photoreceptor isolation method and its applications has been filed by the University of Pennsylvania with Spitschan, Aguirre and Brainard as inventors. In addition, they have founded a company with the Penn UpStart incubator with the goal to commercialize a device based upon these techniques. This work was supported by NIH grants R01 EY020516, R01 EY10016 and P30 EY001583.
Date: November 5, 2014
Source: Stanford University Medical Center
Scientists have found a new way to forecast which patients with age-related macular degeneration are likely to suffer from the most debilitating form of the disease. The new method predicts, on a personalized basis, which patients' AMD would, if untreated, probably make them blind, and roughly when this would occur. Simply by crunching imaging data that is already commonly collected in eye doctors' offices, ophthalmologists could make smarter decisions about when to schedule an individual patient's next office visit in order to optimize the chances of detecting AMD progression before it causes blindness.
Stanford University School of Medicine scientists have found a new way to forecast which patients with age-related macular degeneration are likely to suffer from the most debilitating form of the disease.
The new method predicts, on a personalized basis, which patients' AMD would, if untreated, probably make them blind, and roughly when this would occur. Simply by crunching imaging data that is already commonly collected in eye doctors' offices, ophthalmologists could make smarter decisions about when to schedule an individual patient's next office visit in order to optimize the chances of detecting AMD progression before it causes blindness.
AMD is the leading cause of blindness and central vision loss among adults older than 65. An estimated 10-15 million people in the United States suffer from the disease, in which the macula -- the key area of the retina responsible for vision -- shows signs of degeneration. During normal aging, yellowish deposits called drusen form in the retina, which is the light-sensitive layer of tissue at the back of the eye. As drusen increase in size and number, they eventually begin to damage the light-sensitive cells of the macula. This stage of the disease, called "dry" AMD, can mean blurry central vision and impaired day-to-day activity.
While about four of every five people with AMD have the dry form of the disease, it's the so-called "wet" form that most concerns ophthalmologists, because it accounts for 80-90 percent of all legal blindness associated with the disease. In wet AMD, abnormal blood vessels accumulate underneath the macula and leak blood and fluid. When that happens, irreversible damage to the macula can quickly ensue if not treated quickly.
But until now, there has been no effective way to tell which individuals with AMD are likely to progress to the wet stage. Current treatments are costly and invasive -- they typically involve injections of medicines directly into the eyeball -- making the notion of treating people with early or intermediate stages of AMD a non-starter. Doctors and patients have to hope the next office visit will be early enough to catch wet AMD at its onset, before it takes too great a toll.
Predicting Progression to 'Wet' AMD
In a study published in the November issue of Investigative Ophthalmology & Visual Science, the researchers derived a formula that they say predicts, with high accuracy, whether a patient with mild or intermediate AMD will progress to the wet stage. The formula distinguishes likely from unlikely progressors by analyzing patient data that's routinely collected by ophthalmologists and optometrists when they perform retinal scans with an imaging technique called spectral domain optical coherence tomography.
This imaging technique is analogous to ultrasound: The macula is scanned with a beam of focused laser light, and the amount of reflected light coming back at each point is measured and recorded. The resulting stream of data is computationally converted into an extremely high-resolution, three-dimensional image.
"Right now, a patient who goes into the ophthalmologist's office typically gets an SD-OCT scan anyway," said the study's senior author, Daniel Rubin, MD, assistant professor of radiology and of biomedical informatics. "Our technique involves no new procedures in the doctor's office -- patients get the same care they've been getting anyway. We've simply added on a computerized image-processing step that analyses not only that scan but any previous ones available from that same patient's earlier visits."
Generating a Risk Score
From this computerized analysis, the investigators are able to generate a risk score: a number that predicts a patient's likelihood of progressing to the wet stage within one year, three years or five years. The likelihood of progression within one year is most relevant, because it translates into a concrete recommendation: how soon to schedule the patient's next office visit.
Until now, attempts to predict AMD progression have relied on eye doctors examining color photographs of the retina taken in their offices. There is no way to translate that information into risk scores. The high-resolution imaging technique, Rubin said, provides much richer detail. "You can almost see individual cells," he said. Plus, it is far more amenable to digital analysis. Previously proposed predictive models have shown some accuracy over long periods of time, but none has been adequately accurate over the shorter, one-year time frame that's relevant to making decisions about office-visit frequency, Rubin said.
In the study, the Stanford team analysed data from 2,146 scans of 330 eyes in 244 patients seen at Stanford Health Care over a five-year period. They found that certain key features in the images, such as the area and height of drusen, the amount of reflectivity at the macular surface and the degree of change in these features over time, could be weighted to generate a patient's risk score. Patients were followed for as long as four years, and predictions of the model were compared with actual instances of progression to wet AMD. The model accurately predicted every occurrence of progression to the wet stage within a year. About 40 percent of the time when the model did predict progression to wet AMD within a year, the prediction was not borne out.
"No test gets it right 100 percent of the time," Rubin said. "You can tweak the model to trade off the risk of telling someone they will progress when they actually won't against the risk of telling them they won't progress when they actually will. With AMD you really don't want any false negatives, so you tune the model accordingly. The downside is that some patients will wind up being told to come in sooner than, in fact, they probably need to. But that's nothing compared with the downside of a patient at high risk for progression's not coming in soon enough."
· In the above image, the dark area in the center of the retina is hemorrhage associated with wet AMD.
Credit: Daniel Rubin
Larger Studies Needed
Rubin emphasized that this proof-of-principle study needs to be followed up by a larger study, ideally using data gathered from patients seen at other institutions. He and his associates have now embarked on such a study.
WHAT WAS THAT?
Sudden and unusual noises grab my attention completely.
Recently an intermittent sound had me searching for its location which turned out to be a failing battery in our smoke alarm. A problem easily fixed.
At a recent discussion group, one participant claimed that shopping improved her mood.
As I contemplate the increasing fury of sound as we enter the Christmas cycle in our own shopping centre, I think the term for me to use is "Aversion Therapy".
I realize that some of the constant sounds around our home have become part of my orientation in space. Perhaps this means that while noise can be a problem there are helpful sounds all around us.
ENJOY THE SEASON, AND INTO NEW YEAR 2015.
W.W.B. (WAL BOLIN)
Views expressed in this publication are not necessarily those of Retina Australia (NSW) Inc. Retina Australia (NSW) Inc. accepts no responsibility and disclaims all liability for such views as well as for any information contained in articles and summaries of research reports, including but not restricted to, the use of pharmaceuticals or other products, items of equipment or practices. Retina Australia (NSW) Inc. strongly suggests that persons seek advice from their medical practitioners before adopting any changed procedures, practices or products.