Smartphone Blindness

It has been reported in The New England Journal of Medicine that looking at your smartphone in bed at night could trigger a temporary loss of vision. Symptoms can be mistaken for a mini-stroke. However experts at Moorfields Eye Hospital have noticed the symptoms, usually lasting around 15 minutes, can be the result of looking at a screen in bed.

Two people attended the neuro-ophthalmology clinic at Moorfields Eye Hospital after experiencing repeated episodes of temporary vision loss which occured at night. All examinations and further tests were normal, including cardiovascular checks.

One case was a 40-year-old woman with a six-month history of recurrent loss of vision in one eye, lasting up to 15 minutes. The results of investigations for a vascular cause were again normal.

These symptoms occurred only after several minutes of viewing a smartphone screen, in the dark, while lying in bed (before going to sleep in the first case and after waking in the second). Symptoms were always in the eye opposite to the side on which the patient was lying.

A consultant neurologist at Moorfields, explained that both people typically looked at their smartphones with only one eye while resting on their side in bed in the dark – their other eye was covered by the pillow. While one eye adapts to the dark, the other gets used to the light of the device. When both eyes are opened, the one that has been staring at the screen cannot cope with the darkness and can experience temporary perceived blindness.

These episodes were ultimately harmless. But it is a good reminder, look at your phone with both eyes!

Air Pollution and Glaucoma - a correlation

Photo: Andrew Tunnicliffe

Air pollution may be a modifiable risk factor for glaucoma - timely to consider this as the fires burn on across the Tasman.

Researchers from UCL Institute of Ophthalmology and Moorfields Eye Hospital found that people living in areas with higher amounts of fine particulate matter pollution were at least 6% more likely to report having glaucoma. This was compared to people in the least-polluted areas.

This adds to other evidence that people in urban areas are 50% more likely to have glaucoma than people in rural areas. Air pollution may be a key contributor to that pattern.

“We have found yet another reason why air pollution should be addressed as a public health priority, avoiding sources of air pollution could be worthwhile for eye health alongside other health concerns,” said the study’s lead author, Professor Paul Foster (UCL Institute of Ophthalmology and Moorfields Eye Hospital).

“We hope to continue our research to determine whether air pollution does indeed cause glaucoma, and if there are avoidance strategies that could help people reduce their exposure to air pollution to mitigate the health risks.”

“Most risk factors for glaucoma are out of our control, such as old age or genetics. It’s promising that we may have now identified a second risk factor for glaucoma, after eye pressure, that can be modified by lifestyle, treatment or policy changes,” added Professor Foster.

The findings were based on 111,370 participants of the UK Biobank study cohort, who had eye tests from 2006 to 2010 at sites across Britain. The participants were asked whether they had glaucoma. Then they underwent testing to measure intraocular pressure, and have eye scans.

The data was linked to air pollution measures for their home addresses, from the Small Area Health Statistics Unit, with the researchers focusing on fine particulate matter (equal or less than 2.5 micrometres in diameter, or PM2.5).

The team found that people in the most-polluted 25% of areas were 18% more likely to report having glaucoma than those in the least-polluted quartile. Eye pressure was not associated with air pollution, which suggests that air pollution may affect glaucoma risk through a different mechanism.

Air pollution may be contributing to the constriction of blood vessels, which ties into air pollution’s links to an increased risk of heart problems. Another possibility is that particulates may have a direct toxic effect damaging the nervous system and contributing to inflammation.

Air pollution has been implicated in elevated risk of pulmonary and cardiovascular disease as well as brain conditions such as Alzheimer’s disease, Parkinson’s disease and stroke. Particulate matter exposure is one of the strongest predictors of mortality among air pollutants.

“We found a striking correlation between particulate matter exposure and glaucoma. Given that this was in the UK, which has relatively low particulate matter pollution on the global scale, glaucoma may be even more strongly impacted by air pollution elsewhere in the world. And as we did not include indoor air pollution and workplace exposure in our analysis, the real effect may be even greater,” said Professor Foster.

# AltTextForAll Movement

In October a new movement was launched by Blind & Low Vision NZ. The goal to to make the Internet more accessible by asking us to use the ‘Alt Text’ function when publishing digital images in the ‘#AltTextForAll Movement’.

It involves using the ‘Alt Text’ function to describe images which are uploaded. This is so people with sight loss can participate in the visually-driven digital world by describing the image. More than 6.6 billion images are uploaded everyday to the Internet, but in most cases there is either no description available or a poor attempt made by an AI Bot, which can be inadequate.

To solve the problem ‘#AltTextForAll Movement’ will see the descriptions added to images. The call is coming in the form of an online video featuring Karen, the digital Alt Text voice, explaining ‘Alt Text’.

Blind & Low Vision NZ general manager of marketing and communications Louise von Sierakowski says the #AltTextForAll Movement is easy to get on board with.

“It seems many people aren’t aware of the role Alt Text can play for screen reader users. We hope through this movement that people take a step forward in supporting how those who are blind or have low vision can have independent access to information. It’s simple, but it’s really important.”

Alongside the hero video is a series of smaller videos aimed at international celebrities and organisations, including Ryan Reynolds, Chris Hemsworth, BBC, Ellen, National Geographic and Humans of New York.

Recommendations for healthy young eyes

Recently a concerned school teacher asked me for help. She is noticing changes in work habits of her Year 7 students, aged 11-12. What was our advice and recommendations regarding device use and working habits?

As optometrists we look for clinical guidelines and studies, to give evidence and support to any recommendations. After 4 days in Tokyo at the International Myopia Congress I have met and heard many of the people who are researching and following young people’s eyesight. But clinical studies are often slow to produce results, especially in relation to children.

In terms of preventing myopia (short-sightedness) the biggest recommendation is making sure young children have two hours of outdoors time each day. This has been shown to delay the onset of myopia. Rock solid, with loads of clinical evidence to support this advice.

Here are my recommendations:

Not too close. This is a great one to tell children, first punch yourself in the chin, then don’t let your book/phone/screen come closer to your eyes than your elbow.

Regular Breaks - 20/20. After 20 minutes working/looking at close range, take a break, for 20 seconds.

Good posture makes sense. Hold your phone or screen directly in front, not looking sideways for long periods which is work for your eyes to coordinate.

The challenge and concern for most parents is around restricting the amount of time young people spend on screens. For more informative, research and resources, visit the website Screen Sensible Use, put together by Julie Cullen, a parent and physiotherapist. Julie is collating research and encouraging us all to consider the long term impact of our increasingly digitally focused lifestyle on children’s development. She has excellent references. My Kid’s Vision is an informative website about myopia, with a useful tool to calculate risks of children becoming myopic.

Meantime, apply common sense and if you have any concerns about your young person’s eyesight have them tested.

Considering Myopia Profile - are these eyes at risk?

For much of our working careers helping young people who were myopic (short-sighted) was simply a matter of prescribing glasses or contact lenses. Then adjusting the strength of the prescription as eyesight continued to deteriorate through the teenage years.

These days we know so much more about myopia, and how to we can manage myopia to try to slow down the rate of progression.

The best time to start is before eyes have become myopic, when we can identify young eyes at risk.

This tool shows how we evaluate the risk of a child developing myopia.

The good news - we can modify environmental risk factors.

If you have any questions, or would like to know more please get in touch.

What to expect at an eye examination?

If you are coming for your first eye examination what can you expect?

The foundation is your concerns. We would like to hear of any issues you have with your eyes, your vision, or your glasses and any problems you may have had with your eyes in the past, even if it is years ago. This is all useful and important.

Your eyesight will then be measured - “what size letter can you read on the chart”. Next will be a series of questions, “which is better lens 1 or 2”, as we refine and optimize your vision. The end result is a prescription which we can use for any glasses, or simply to compare with your existing pair.

Onto the health checks when we will examine your eyes on the microscope, starting at the front with the lids and eyes surface, moving through to the retina and nerve at the back (read more about what we see inside your eyes.) We will measure the eye pressure with a tonometer. This is important because increasing eye pressure means a greater the risk of getting glaucoma.

Sometimes we will recommend further testing, commonly a peripheral vision screening test. This test shines light in your field of vision where there would be reduced sensitivity in early glaucoma. We often use OCT scans to show a more detailed picture of the retina inside the eye.

With all this information we can help work out the solution for any difficulties you are having. Or simply be able to reassure you that your eyes and vision all look good - which is worth coming in for.

If we are recommending glasses, either first time glasses or a change to your current glasses, we will show you what to expect by mocking up lenses in a trial frame. Our team includes Dispensing Opticians who help with lenses, frames and sunglasses choices.

If you have any questions about having your eyes checked, don’t hesitate to contact us.