It’s never too early for children get their first eye exam, according to the American Academy of Ophthalmology. “Babies must have a vision screening by a health care professional soon after they are born, which must include an evaluation of the ‘red reflex’ of the eyes,” says Marcela Frazier, O.D., associate professor in the Department of Ophthalmology and Visual Sciences. “If an eye problem is suspected, then a comprehensive eye exam that includes the use of eye drops to dilate the pupil should be scheduled immediately. Children with developmental delays should also have a comprehensive eye exam, even if the vision screening is normal."
A dilated eye exam differs from a vision screening. “Vision screenings are good for detecting eye and visual conditions that may require further testing,” School of Optometry Professor Katherine Weise, O.D., said. “A dilated eye exam allows for a more comprehensive look at the health of the eye. It also allows the eye doctor to determine the best glasses prescription for the child, if needed. The drops make it difficult for the child to see up close for a while and create a sensitivity to light. However, more accurate information is obtained from eye doctors who use dilating drops to examine the eyes of children.”
There are signs to look for that your child may have blurred or improper vision. Children do not typically complain about their vision, and there are many signs parents and teachers should look for when it comes to children. “Squinting indicates a potential need for glasses, and covering an eye while reading indicates a potential difficulty in getting the eyes to work together efficiently,” Weise said. “Complaints of eyestrain, intermittent blur or double vision, frequent headaches during the school week, or skipping lines and words when reading may indicate a problem coordinating the eyes and tracking properly while reading.”
A white light reflecting from one of the pupils can indicate an eye turn or something more serious. Parents or pediatricians who discover this should seek an eye doctor immediately.
Children’s Eye Injuries
Trauma to the eye - such as a ball hitting the eye - can cause serious vision difficulty. “Sport-related eye injuries are very common; therefore, we recommend sports goggles,” Frazier said. “Injuries due to BB guns and fireworks are also very prominent. Some toys can have sharp edges that can cause injuries, so proper parental supervision is a must. Some household cleaning items can cause severe damage when they come in contact with the eye; they must be stored away from the reach of children.”
It’s also important to know what kind of eye protection your child should wear during sports. “Some sports require goggles to be worn at all times,” Frazier said. “If the child needs corrective lenses to see well, the safest are sports goggles with polycarbonate lenses.”
Eyes Can Detect Early Sign Of Parkinson's Disease
People with early Parkinson's disease gradually lose brain cells that produce dopamine, a substance that helps control movement. A recent study published in Neurology found that the thinning of the retina, the lining of nerve cells in the back of the eye, is linked to the loss of such brain cells. "Our study is the first to show a link between the thinning of the retina and a known sign of the progression of the disease - the loss of brain cells that produce dopamine," says study author Jee-Young Lee, MD, Ph.D., of the Seoul Metropolitan Government - Seoul National University Boramae Medical Center in South Korea. "We also found the thinner the retina, the greater the severity of disease. These discoveries may mean that neurologists may eventually be able to use a simple eye scan to detect Parkinson's disease in its earliest stages, before problems with movement begin.
Forty-nine people with an average age of 69 who were diagnosed with Parkinson's disease an average of two years earlier but who had not yet started medication took part in the study. They were compared to 54 people without the disease who were matched for age. Researchers evaluated each study participant with a complete eye exam as well as high-resolution eye scans that use light waves to take pictures of each layer of the retina. Twenty-eight of the participants with Parkinson's disease also had dopamine transporter positron emission tomography imaging to measure the density of dopamine-producing cells in the brain.
Researchers found retina thinning, most notably in the two inner layers of the five layers of the retina, in those with Parkinson's disease. For those with Parkinson's disease, the inner most layer of the retina in one section of the eye had an average thickness of 35 micrometers compared to an average thickness of 37 micrometers for those without the disease. The thinning of the retina corresponded with the loss of brain cells that produce dopamine. It also corresponded with the severity of disease.
When disability from the disease is measured on a scale of one to five, the people with the most thinning of the retina, or thickness of less than 30 micrometers, had average scores of slightly over two, while people with the least thinning, or thickness of about 47 micrometers, had average scores of about 1.5. "Larger studies are needed to confirm our findings and to determine just why retina thinning and the loss of dopamine-producing cells are linked," said Lee. "If confirmed, retina scans may not only allow earlier treatment of Parkinson's disease but more precise monitoring of treatments that could slow progression of the disease as well."
Half Of Vision Impairment In First World Is Preventable
A recent study published in the British Journal of Ophthalmology says that around half of vision impairment in Western Europe is preventable. The study was carried out by the Vision Loss Expert Group, led by Professor Rupert Bourne of Anglia Ruskin University, and shows the prevalence and causes of vision loss in high income countries worldwide as well as other European nations in 2015, based on a systematic review of medical literature over the previous 25 years.
The study showed that the United Kingdom has the fifth lowest prevalence of blindness in the over 50s out of the 50 countries surveyed, with 52 percent of men and women in that age group affected. Belgium had the lowest prevalence at 46 percent. However, in terms of the percentage of population with moderate to severe vision impairment, the UK ranked in the bottom half of the table with 6.1 percent, a higher prevalence than non-EU countries such as Andorra, Serbia and Switzerland.
Cataract was found to be the most common cause of blindness in Western Europe in 2015: 21.9 percent, followed by age-related macular degeneration – 16.3 percent - and glaucoma with 13.5 percent. The main cause of moderate to severe vision impairment was uncorrected refractive error - a condition that can be treated simply by wearing glasses. This condition made up 49.6 percent of all moderate to severe vision impairment in Western Europe. Cataract was the next main cause in this region, with 15.5 percent, followed by age-related macular degeneration.
The contribution of the surveyed countries to the world's vision impaired is expected to lessen slightly by 2020, although the number of people in these nations with impaired sight will rise overall to 69 million due to a rising overall population. "Vision impairment is of great importance for quality of life and for the socioeconomics and public health of societies and countries,” says Rupert Bourne, Professor of Ophthalmology at Anglia Ruskin University's Vision and Eye Research Unit. "Overcoming barriers to services which would address uncorrected refractive error could reduce the burden of vision impairment in high-income countries by around half.
“This is an important public health issue even in the wealthiest of countries and more research is required into better treatments, better implementation of the tools we already have, and ongoing surveillance of the problem,” Bourne continued. "This work has exposed gaps in the global data, given that many countries have not formally surveyed their populations for eye disease. That is the case for the UK and a more robust understanding of people's needs would help bring solutions."
Vision Keeps Maturing Until Mid-Life
Research in The Journal of Neuroscience states the visual cortex - the human brain's vision-processing center that was previously thought to mature and stabilize in the first few years of life - actually continues to develop until sometime in the late 30s or early 40s, a McMaster neuroscientist and her colleagues have found. Kathryn Murphy, a professor in McMaster's department of Psychology, Neuroscience and Behaviour, led the study using post-mortem brain-tissue samples from 30 people ranging in age from 20 days to 80 years. Her analysis of proteins that drive the actions of neurons in the visual cortex at the back of the brain recasts previous understanding of when that part of the brain reaches maturity, extending the timeline until about age 36, plus or minus 4.5 years.
The finding was a surprise to Murphy and her colleagues, who had expected to find that the cortex reached its mature stage by five to six years, consistent with previous results from animal samples and with prevailing scientific and medical belief. "There's a big gap in our understanding of how our brains function," says Murphy. "Our idea of sensory areas developing in childhood and then being static is part of the challenge. It's not correct."
Treatment for conditions such as amblyopia or "lazy eye," have been based on the idea that only children could benefit from corrective therapies, since it was thought that treating young adults would be pointless because they had passed the age when their brains could respond. Though the research is isolated to the visual cortex, it suggests that other areas of the brain may also be much more plastic for much longer than previously thought.