http://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. (Phys.org)—The eye, whether in humans or other animals, is truly one of nature's most sophisticated advancements, able to convert light into signals the brain can interpret as imagery, all in real time. Most of the actual work is done at the back of the eye where rods and cones, two types of photoreceptors are located. Cones are primarily responsible for the eye's sensitivity to color, while rods, which are far more numerous (some 120 million exit in one human eye), are more sensitive to light in general. To find out just how sensitive rods are, researchers in Singapore have been studying single rod photoreceptors taken from an African Clawed Frog, and have found, as they describe in their paper published in Physical Review Letters, that such rods are able to discern and count single photons and are also able to determine the coherence of very weak pulses of light. http://phys.org/news266825802.html Physics Fri, 14 Sep 2012 07:17:02 EST news266825802 A student at the University of Kansas School of Engineering has taken the first steps that could unlock new details about how extinct animals lived and hunted on a daily basis. http://phys.org/news266657526.html Other Sciences Wed, 12 Sep 2012 08:32:13 EST news266657526 (Phys.org) -- In the eye, the retina is the light sensitive tissue that lines its inner surface; packed with ganglion neurons, its job is to convert incoming information to something that the brain can understand. In some animals, such as people, cats and the macaque, the density of neurons in certain areas of the retina accounts for the highest resolution images sent to the brain. But some animals apparently reserve such areas for other jobs. Mice for example, according to new research by a team from Harvard, only use their high resolution areas when under threat from above. As they describe in their paper published in the Proceedings of the National Academy of Sciences, the team notes that high density neural areas in the retinas of mice are only activated when shadows from birds flying overhead are detected. http://phys.org/news264147762.html Biology Tue, 14 Aug 2012 07:23:02 EST news264147762 Magnetic resonance imaging (MRI) of the eyes and brains of 27 astronauts who have spent prolonged periods of time in space revealed optical abnormalities similar to those that can occur in intracranial hypertension of unknown cause, a potentially serious condition in which pressure builds within the skull. A retrospective analysis of the MRI data appears online in the journal Radiology. http://phys.org/news250831387.html Space & Earth Tue, 13 Mar 2012 04:50:02 EST news250831387 (PhysOrg.com) -- Scientists have a good overall understanding of human vision: when light enters our eyes, it is focused by the lens and strikes the retina in the back of the eye. The light causes some of the millions of photoreceptor cells that line the retina to undergo a chemical change, which send a message through the optic nerve fiber to the brain, which creates a picture. However, there are still a few unresolved questions in the details of the vision process, one of which is why the eye evolved to use a certain light-absorbing chromophore called 11-cis-retinal instead of one of its isomers (i.e., molecules with the same atoms but in different arrangements), such as 7-cis, 9-cis, or 13-cis. http://phys.org/news240735271.html Chemistry Thu, 17 Nov 2011 09:00:02 EST news240735271 (PhysOrg.com) -- University of Oregon researcher Richard Taylor is on a quest to grow flowers that will help people who've lost their sight, such as those suffering from macular degeneration, to see again. http://phys.org/news223832416.html Physics Thu, 05 May 2011 17:10:01 EST news223832416 Using a method that involved the clustering of samples that showed similarity in expression profiles, Jackson Laboratory researchers were able to identify molecular signatures of early events in glaucoma progression -- events that were detectable before there was morphological evidence of damage. http://phys.org/news218724062.html Medicine & Health Mon, 07 Mar 2011 13:40:01 EST news218724062 For two decades, Eric Selby had been completely blind and dependent on a guide dog to get around. But after having an artificial retina put into his right eye, he can detect ordinary things like the curb and pavement when he's walking outside. http://phys.org/news216895236.html Medicine & Health Mon, 14 Feb 2011 08:40:52 EST news216895236 In a study published today in the Proceedings of the National Academy of Sciences (Early Edition ahead of print), a team of researchers from the Kennedy Krieger Institute and four collaborating institutions, identified a new and unexpected biological pathway that appears to contribute to the development of glaucoma and its resulting vision loss. http://phys.org/news213292321.html Medicine & Health Mon, 03 Jan 2011 15:52:24 EST news213292321 This month's Ophthalmology journal includes surprising research from the Massachusetts Eye and Ear Infirmary on the relation of body weight to the risk for glaucoma. Also, from researchers at the Tokyo Medical and Dental University, comes the first specific map of how the development of myopic maculopathy, an illness that afflicts many severely nearsighted people, predicts which patients will be most susceptible to vision loss. http://phys.org/news199970942.html Medicine & Health Mon, 02 Aug 2010 12:29:19 EST news199970942 The most common - and under-diagnosed - genetic disease in humans just may be a cause of the worst form of macular degeneration, Medical College of Georgia researchers report. http://phys.org/news196596681.html Medicine & Health Thu, 24 Jun 2010 11:11:51 EST news196596681 (AP) -- Dozens of people who were blinded or otherwise suffered severe eye damage when they were splashed with caustic chemicals had their sight restored with transplants of their own stem cells - a stunning success for the burgeoning cell-therapy field, Italian researchers reported Wednesday. http://phys.org/news196533786.html Medicine & Health Wed, 23 Jun 2010 17:43:40 EST news196533786 June 8, 2010 - A quick, painless eye measurement shows promise as a way to diagnose multiple sclerosis in its very early stages, and to track the effectiveness of treatments, researchers from UT Southwestern Medical Center have found in a multicenter study. http://phys.org/news195147358.html Medicine & Health Mon, 07 Jun 2010 17:00:01 EST news195147358 UC Irvine scientists have created an eight-layer, early-stage retina from human embryonic stem cells, the first three-dimensional tissue structure to be made from stem cells. http://phys.org/news194117951.html Medicine & Health Wed, 26 May 2010 18:39:29 EST news194117951 The eyes are marvelous instruments for converting outside reality into images lodged inside our brains. A new study of the retina, the light-sensitive region at the back of the eye, solves a mystery as to why the images we see are so sharp. http://phys.org/news192634050.html Physics Sun, 09 May 2010 14:27:55 EST news192634050 An eye under pressure appears to express a unique set of proteins that physicians hope will one day help them better diagnose and treat glaucoma. http://phys.org/news192193503.html Medicine & Health Tue, 04 May 2010 12:30:24 EST news192193503 Scientists are reporting progress toward a test that could revolutionize the diagnosis of glaucoma -- the second leading cause of vision loss and blindness worldwide -- by detecting the disease years earlier than usually happens at present. They reported the findings here today at the 239th National Meeting of the American Chemical Society (ACS). http://phys.org/news188668407.html Medicine & Health Wed, 24 Mar 2010 17:20:03 EST news188668407 Researchers at the Vanderbilt Eye Institute are now a step closer to deciphering a leading cause of blindness in the United States - glaucoma. http://phys.org/news186669414.html Medicine & Health Mon, 01 Mar 2010 15:00:01 EST news186669414 Ask anyone who suffers from migraine headaches what they do when they're having an attack, and you're likely to hear "go into a dark room." And although it's long been known that light makes migraines worse, the reason why has been unclear. http://phys.org/news182326430.html Medicine & Health Sun, 10 Jan 2010 13:00:14 EST news182326430 Researchers led by specialists at the Johns Hopkins Wilmer Eye Institute have found that injecting a corticosteroid, triamcinolone, directly into the eye may slow the progression of proliferative diabetic retinopathy, a complication of diabetes that frequently leads to blindness. http://phys.org/news181213710.html Medicine & Health Mon, 28 Dec 2009 10:30:01 EST news181213710 (PhysOrg.com) -- Acute optic neuritis, an inflammation of the optic nerve, doesn't occur all that often. But for those who experience it, the vision loss, pain and nerve damage that often result are no small matter. A clinical trial is investigating whether or not a drug currently used to treat multiple sclerosis may protect the nerve from damage due to optic neuritis. http://phys.org/news180647068.html Medicine & Health Mon, 21 Dec 2009 19:44:55 EST news180647068 Brain and spinal-cord injuries typically leave people with permanent impairment because the injured nerve fibers (axons) cannot regrow. A study from Children's Hospital Boston, published in the December 10 issue of the journal Neuron, shows that axons can regenerate vigorously in a mouse model when a gene that suppresses natural growth factors is deleted. http://phys.org/news179584849.html Medicine & Health Wed, 09 Dec 2009 12:50:01 EST news179584849 A small group of patients with severe Graves' eye disease experienced rapid improvement of their symptoms — and improved vision — following treatment with the drug rituximab. Inflammation around their eyes and damage to the optic nerve were significantly reduced. The same patients had not previously responded to steroids, a common treatment for Graves' eye disease. http://phys.org/news176737372.html Medicine & Health Fri, 06 Nov 2009 13:43:30 EST news176737372 A 50-year-old New York woman who was diagnosed with a progressive blinding disease at age 13 was implanted with an experimental electronic eye implant that has partially restored her vision. A team led by Dr. Lucian V. Del Priore at NewYork-Presbyterian Hospital/Columbia University Medical Center performed the June 26 surgery -- the first case of its kind in New York. http://phys.org/news175359356.html Medicine & Health Wed, 21 Oct 2009 16:20:01 EST news175359356 This month's Ophthalmology, the journal of the American Academy of Ophthalmology, reports on use of bevacizumab (Avastin), to benefit diabetic patients with macular edema as well as people who develop cystoid macular edema after cataract surgery. Bevacizumab is also used to treat some cancers. Another study describes methods that could make cataract surgery safer for diabetic retinopathy (DR) patients. DR is the major threat to vision in working-age people, a problem that will only intensify if cases triple by 2050 as predicted. http://phys.org/news168263908.html Medicine & Health Fri, 31 Jul 2009 13:10:07 EST news168263908 Variations in how people perceive colors and how those same colors appear on TV, computers and other media have confounded broadcasters, Web designers and printers trying to reproduce lifelike hues. http://phys.org/news165513181.html Other Sciences Mon, 29 Jun 2009 17:10:01 EST news165513181 Dr. Michael Walter is one good gumshoe. The University of Alberta medical geneticist has cracked the case of WDR36, a gene linked to glaucoma. http://phys.org/news156761935.html Medicine & Health Fri, 20 Mar 2009 09:59:30 EST news156761935 One of the most pernicious aspects of multiple sclerosis (MS) — its sheer unpredictability — may finally be starting to yield to advanced medical imaging techniques. http://phys.org/news148672324.html Medicine & Health Tue, 16 Dec 2008 17:52:04 EST news148672324 Magnetic resonance imaging (MRI) measurements of the thickness of the optic nerve sheath are a good marker for raised intracranial pressure (ICP). New research published today in BioMed Central's open access journal Critical Care shows that a retro-bulbar optic nerve sheath diameter (ONSD) above 5.82mm predicts raised ICP in 90% of cases. http://phys.org/news140336465.html Medicine & Health Thu, 11 Sep 2008 07:21:05 EST news140336465