According to a study published online in the British Journal of Ophthalmology there are over 200, 000 eye doctors in practice across the world. However, this is not enough to keep up with the current needs of developing countries and the increasing demands of aging populations. The study findings are based on an International Council of Ophthalmology survey that involved 213 ophthalmic societies in 193 countries between March and April 2010. The survey was created in order to determine how many ophthalmologists are currently practicing in each country, as well as to determine the growth rate of the profession. Of the 193 countries 192 responded. Results showed that in 2010, half of the 205, 000 ophthalmologists were in the USA, China, Japan, India, Russia, and Brazil. Results showed that the number of ophthalmologists practicing by country varied between 0 to over 28, 000 in China.
When observing a fly buzzing around the room, we should have the impression that it is not the fly, but rather the space that lies behind it that is moving. After all, the fly is always fixed in our central point of view. But how does the brain convey the impression of a fly in motion in a motionless field? With the help of functional magnetic resonance imaging (fMRI) scientists from the Werner Reichardt Centre for Integrative Neuroscience and the Max Planck Institute for Biological Cybernetics in TÃ bingen have identified two areas of the brain that compare the movements of the eye with the visual movements cast onto the retina so as to correctly perceive objects in motion. The two areas of the brain that are particularly good at reacting to external movements, even during eye movements, are known as V3A and V6.
Jackson Laboratory researchers have demonstrated that a single, targeted x-ray treatment of an individual eye in young, glaucoma-prone mice provided that eye with apparently life-long and typically complete protection from glaucoma. In research published March 19 in the Journal of Clinical Investigation, Gareth Howell, Ph.D., Simon John, Ph.D., (professor and Howard Hughes Medical Investigator) and colleagues also used sophisticated genomics methods to uncover some of the very first pathways to change during glaucoma in these mice. The first pathway they detected to change suggests a critical mechanism that could be responsible for the earliest damage that glaucoma inflicts on the optic nerve. Glaucoma, a leading cause of blindness, affects more than 4 million Americans, at least half of who don't even know they have the disease.
A clearer understanding of glaucoma Glaucoma is one of the leading causes of vision loss and blindness worldwide. In glaucoma patients, the optic nerve, which relays information from the eye to the brain, is damaged, though the molecular cause of nerve damage is unclear. Dr. Simon John, from Tufts University in Boston, and colleagues specifically wanted to understand the earliest events that lead to optic nerve damage in glaucoma. Using a mouse model of the disease, the researchers showed that inflammatory immune cells called monocytes cross blood vessels and invade the optic nerve. Remarkably, mice treated with a single X-ray treatment in eyes prior to the onset of glaucoma were protected from developing the disease later in life. Through an unknown mechanism, the X-ray treatment prevented neuroinflammation and allowed mice to avoid glaucoma development, even in the presence of other risk factors.
A new US study suggests that screening for retinopathy, a disease of blood vessels in the retina at the back of the eye, could serve as a marker for brain health, after researchers found that women aged 65 and over with even a mild form of the disease were more likely to have cognitive decline and related vascular changes in the brain. For the study, lead author Dr Mary Haan, professor of epidemiology and biostatistics at the University of California, San Francisco (UCSF), and colleagues, used data from the Women's Health Initiative Memory Study and the Site Examination study, two sub-investigations of the Women's Health Initiative Clinical Trial of Hormone Therapy. The findings, which they report in the 14 March online issue of Neurology, suggest that a simple eye test could look for early signs of retinopathy, and serve as a marker for cognitive changes linked to vascular disease.