Thursday, January 19, 2017

An early study shows the positive effects of sleeping with an LED light mask on retinal disease.

Patients with diabetic macular oedema showed improvements in their retina after sleeping with a
light emitting diode (LED) sleep mask, in a small study by UK scientists.

The team, based in Liverpool and Durham, monitored the effects of the organic light masks on 60 volunteers who wore them for three months, followed by a one-month recovery period.

The participants were a group aged 18–30, a group aged 50–70 and a group of patients with diabetic macular oedema. The latter group showed a significant level of retinal thinning during the study.

More than two in three patients also had cysts in their eyes either reduce or resolve completely, according to the paper published in the journal Eye.

However, the study did find that the use of the masks came at a price – patients demonstrated lower daytime alertness and wellbeing. Over the study period, 16 patients also withdrew.

Despite these issues, the authors wrote that, with the preliminary data showing a beneficial effect on the symptoms of patients with diabetic macular oedema, “This novel therapeutic approach is ready for large clinical trials.”

Image credit: Deeped Niclas & Amanda Strandh

Wednesday, January 11, 2017

Stem cell therapy reverses blindness in animals with end-stage retinal degeneration

A stem cell-based transplantation approach that restores vision in blind mice moves closer to being tested in patients with end-stage retinal degeneration, according to a study published January 10 in Stem Cell Reports. The researchers showed that retinal tissue derived from mouse induced pluripotent stem cells (iPSCs) established connections with neighboring cells and responded to light stimulation after transplantation into the host retina, restoring visual function in half of mice with end-stage retinal degeneration.

"Our study provides a proof of concept for transplanting stem cell-derived retinal tissues to treat patients with advanced retinitis pigmentosa or age-related macular degeneration," says senior study author Masayo Takahashi of the RIKEN Center for Developmental Biology. "We are planning to proceed to clinical trials after some more additional studies, and hope to see these effects in patients as well."

End-stage retinal degeneration is a leading cause of irreversible vision loss and blindness in older individuals. Typically, patients with conditions such as retinitis pigmentosa and age-related macular degeneration lose vision as a result of damage to the outer nuclear layer of light-sensitive photoreceptor cells in the eye. There is no cure for end-stage retinal degeneration, and currently available therapies are limited in their ability to stop the progression of vision loss.

One strategy to restore vision in patients who are blind from outer retinal degeneration is cell replacement. Toward that goal, Takahashi and her team recently showed that stem cell-derived retinal tissues could develop to form structured outer nuclear layers consisting of mature photoreceptors when transplanted into animals with end-stage retinal degeneration. But until now, it was not clear whether transplantation of these cells could restore visual function.

In the new study, Takahashi and first author Michiko Mandai of the RIKEN Center for Developmental Biology set out to address that question. To do so, they first genetically reprogrammed skin cells taken from adult mice to an embryonic stem cell-like state, and then converted these iPSCs into retinal tissue. When transplanted into mice with end-stage retinal degeneration, the iPSC-derived retinal tissue developed to form photoreceptors that established direct contact with neighboring cells in the retina.

"We showed the establishment of host-graft synapses in a direct and confirmative way," Mandai says. "No one has really shown transplanted stem cell-derived retinal cells responding to light in a straightforward approach as presented in this study, and we collected data to support that the signal is transmitted to host cells that send signals to the brain."

Moreover, almost all of the transplanted retinas showed some response to light stimulation. The key to success was to use differentiated retinal tissue instead of retinal cells, which most researchers in the field use. "The photoreceptors in the 3D structure can develop to form more mature, organized morphology, and therefore may respond better to light," Takahashi explains. "From our data, the post-transplantation retina can respond to light already at one month in mice, but since the human retina takes a longer time to mature, it may take five to six months for the transplanted retina to start responding to light."

Remarkably, this treatment strategy restored vision in nearly half of the mice with end-stage retinal degeneration. When these mice were placed in a box consisting of two chambers that independently delivered electric shocks on the floor, they were able to use a light warning signal to avoid the shocks by moving into the other chamber. "We showed that visual function could be restored to some degree by transplantation of the iPSC-derived retina," Mandai says. "This means that those who have lost light perception may be able to see a spot or a broader field of light again."

To make the findings more applicable to patients, the researchers are currently testing the ability of human iPSC-derived retinal tissue to restore visual function in animals with end-stage retinal degeneration. If these experiments are successful, they will then test the safety of this protocol in part by assessing how the host retina responds to the graft. At the same time, they will continue to search for ways to increase the ability of graft photoreceptors to integrate with the host retinal tissue, with the ultimate goal of moving to clinical trials in humans.

"It is still a developing-stage therapy, and one cannot expect to restore practical vision at the moment," Takahashi cautions. "We will start from the stage of seeing a light or large figure, but hope to restore more substantial vision in the future."

Wednesday, December 28, 2016

Combatting Dry Eyes During the Winter

December 21 marked the first official day of winter which means subzero temperatures are in full swing across Canada. Some enjoyable aspects come with the cold, like delicious hot chocolate and ski season, but it also has its downsides as well – icy roads, wind burned cheeks, and chapped lips.
Another drawback you may notice as the temperatures continue to drop is irritated, dry eyes. The contrast between the brisk temperatures outdoors and dry head inside can cause our eyes to become dehydrated quicker during the winter creating a stinging, itching, or burning sensation as your glands struggle to produce enough tears.
We’ve developed a list of Do’s and Don’ts to help keeping your eyes hydrated and healthy throughout the 2016-2017 winter season:
DO
  • Use a humidifier: Offset the dry air in your home during the winter by using a humidifier, which increase the home’s humidity level that can dip during the winter months. In doing so, the humidity within your home can remain in the 30-55 percent range it requires for your eyes to remain lubricated.
  • Hydrate through foods: Up your intake of fluid-rich foods such as fruits, veggies, and soups throughout the winter to counteract the dehydration affects that can easily occur within your body, which quickly impacts the water development in the eyes.
  • Get your fix of omega-3 fatty acids: Increase your intake of omega-3 fatty acids through food or fish oil supplements to help improve the quality of your eye glands that often become inflamed from the winter’s dry air.
  • Use artificial tears: Using eye drops up to four times per day can provide your eyes with the lubricant they need when they become dry. Artificial tear drops can be purchased over the counter at a local drug store for mild cases of dry eyes, or your doctor may prescribe prescription medication for more serious conditions.
DON’T
  • Do not blow heat directly at your face: We’re all guilty of instinctively blasting hot air in the car to warm up, but it’s this habit that causes the eyes to dry out faster. As an alternative measure to staying warm in the car, direct the heat to the feet and window vents and use seat warmers if available.
  • Do not overconsume diuretic drinks: Be mindful of your consumption of diuretic drinks throughout the winter, such as coffee, tea and soda, as they can speed up dehydration affects in the body leaving your eyes irritated.
Occasionally, dry eyes can progress into a more serious eye condition which is why it’s important to make regular appointments to have your eyes examined by a local doctor of optometry.
Happy holidays and a happy new year!

Tuesday, December 13, 2016

UV damage doesn’t end when summer does

by Dr. Riaz Ahmed, past-president of the Alberta Association of Optometrists
During a recent ski trip to Banff, I was surprised to witness the number of people on the mountain without any type of protective eyewear. While most skiers, snowboarders and snowshoers on the mountain had the proper gear to protect their head, body, hands and feet, they fell short on protecting one of their bodies’ most valuable assets – their eyes.
I was reminded that many people think that protecting their eyes from the sun is only necessary when it’s warm outside. During the summer months, the mental checklist for sun protection includes sunscreen, sunglasses and a hat. However, it’s easy to forget to take these same protective measures once the snow starts to fall.
The danger in this situation is ultraviolet (UV) radiation — invisible rays of energy emitted from the sun 365 days a year. There are two main types of UV rays that reach the earth’s surface, known as UVA and UVB, both of which can have damaging effects on eyes and skin. When eyes absorb too much UV light, it can lead to serious eye conditions such as cataracts, retinal damage, growths on the front of the eye and eye cancers, especially on the delicate skin surrounding the eyes. People with lighter coloured eyes and skin are even more at risk for damage as they have less of the protective pigment that helps absorb these rays.
Unfortunately, many simply don’t understand the long-term damage UV rays can have. According to the Canadian National Institute For the Blind (CNIB), only nine per cent of Canadians are aware that sun can cause permanent harm to their eyes. While UV rays are undoubtedly stronger during the spring and summer months, people shouldn’t ignore these harmful effects as soon as fall arrives. Those who are keen to get on the mountain after the first snow fall should be particularly mindful since UV exposure increases on reflective surfaces, such as snow.
There are several proactive measures you can take to ensure your eyes remain in good health. The first step is to be cautious year-round while exposing your eyes to the sun. Wearing proper protective gear is important, which includes UV-blocking sunglasses with wrap-around frames to keep the sun out from the sides, and broad-brimmed hats.
Second, maintain regular visits with your optometrist who will assess your individual eye health and discuss the best options for protecting your eyes year-round. The Alberta Association of Optometrists recommends that adults have an eye exam every one to two years, and at least annually for those over 65 depending on the presence of eye disease. Children should have their first eye exam at six months, again at age three, and every year while they are in school.
Comprehensive eye exams with a doctor of optometry can also reveal insight about your overall health. These visits not only allow an optometrist to detect eye diseases, but also uncover serious health conditions which often have early warning signs present in the eye.
For example, optometrists often identify nevi (similar to skin moles or freckles) in the pigmented layer at the back of the eye. If exposed to UV rays over a lifetime, these can develop into a rare form of cancer called choroidal melanoma, which can be deadly if not treated. Also, as mentioned earlier, the eyelid area is one of the areas of the body where skin cancer is first diagnosed. The most common form is invasive lesions called basal cell carcinomas that grow deep into the surrounding tissue.
Perhaps the most important lesson to be learned about the eyes is this: good vision and good eye health are often unrelated. You may have 20/20 vision but you may also have risk factors for UV related eye disease. For this reason, it’s important to remember eye protection year-round.
Whether you’re skiing on top of a mountain or sitting on a beach chair on your well-deserved winter vacation, remember to protect your most precious sense against the harmful effects of UV rays.

Tuesday, December 6, 2016

How binge watching TV shows can impact your eyes

As we head into the long, dark and cold winter months, binge watching your favourite TV shows may become unavoidable. And let’s be honest, services like Netflix and Crave make it entirely too easy to do so.
Adults in Canada between the ages of 18 to 34 spend an average of 17.7 hours per week watching TV, that’s around 2.5 hours each day. However, many fail to acknowledge the negative effects the extended hours in front of the television has on the body, which in large part has to do with your eyes.
Overexposure to the TV can cause eye muscle fatigue, resulting in headaches and the reduced ability for our eyes to change focus when looking away from the TV. We also blink half as much while watching TV, causing our eyes to become dry, red and irritated. A lot of people will experience these common symptoms; however, many don’t recognize it’s due to eye strain. Instead, they’ll chalk it up to a simpler explanation, such as being tired.
Ironically, TV is a common contributor in people’s inability to sleep at night. Watching TV during the evening hours impacts our mind’s ability to unwind, and also suppresses melatonin production, which our brain produces to regulate our sleep cycle.
Too much TV time may also have other negative health effects, including a slowed down metabolism, muscle cramps, and poor blood circulation.
To discuss any recurring symptoms that might be the result of eye muscle strain, or perhaps a more serious vision condition, make sure to book regular appointments with one of our Doctors of Optometry.

Tuesday, November 29, 2016

Did you know cold-water fish are a great source of omega-3-fatty acids?

For your eye health cold-water fish has protective effects against AMD, cataracts and dry eye syndrome because of its high concentration of omega-3-fatty acids (DHA and EPA).

Omega 6 and Omega 3 Fatty Acids:
  • Omega 3 fatty acids are anti-inflammatory. Omega 6 fatty acids are pro-inflammatory.
  • It’s all about balance, the ideal ratio of Omega 6 to Omega 3 is 4:1 or less. The average North American has a ratio of 15:1 or higher. 
  • Avoid foods that are high in omega 6 fatty acid such as processed foods.
  • Look for foods high in omega 3 fatty acids – such as cold-water fish.
Eyefoods Fish Recommendations:
  • Eat cold water fish, 4 per week gives you 850mg of DHA and EPA per day.
  • One Eyefoods serving of fish is the size of a deck of cards.
  •  Small fish tend to have fewer contaminants such as mercury and PCB’s when compared to larger fish.
  • Eat wild salmon, sardines, rainbow trout and mackerel – they are high in omega 3 fatty acids and low in contaminants.

Tuesday, November 22, 2016

The cost of diabetes for Canadians

Diabetes currently affects more than five million people across Canada, and those who have been diagnosed understand that the chronic disease not only imposes a significant impact on their health, but their financial state as well.

In a report commissioned by the Canadian Diabetes Association, the costs directly associated with diabetes can range from $1,000 to $15,000 per year, including payment for treatment, care and rehabilitation.

Diabetes doesn’t only have personal financial consequences on those affected. The rapid rate in which Canadian’s are being diagnosed with diabetes has a costly impact on the workplace and economy as well. The economic burden of diabetes in Canada is expected to reach approximately 23 billion dollars by 2020, and a recent article by the Regina Leader Post indicated that diabetes can cost employers between $400 to $1,000 per person per year.

33 per cent of Canadians are living with diabetes or prediabetes and many are not aware of their condition. The longer diabetes goes undiagnosed, the greater the burden can become both financially and medically. Early diagnosis can be cost effective by reducing future medical complications. Diabetic retinopathy is currently the leading cause of one of these complications, legal blindness.

Doctors of Optometry along with the entire team of medical health professionals stress the importance of reducing risk of diabetes with lifestyle choices like maintaining a healthy body weight, consuming a healthy diet, and exercising regularly. It’s ultimately important to book yearly comprehensive eye exams. Eye exams allow optometrists the ability to look at the tiny structures within the eyes, which can provide indicators of various health complications.