Primer on Charles Bonnet Syndrome

Charles Bonnet (pronounced “bon-nay”) was a naturalist and philosopher born in Geneva in 1720. At around 40 years-old, he released a book called “Essai Analytique sur les Faculties de L’Ame” (Analytical Essays Concerning the Faculties of the Mind) in which he described how his 87 year-old grandfather, Charles Lullin, experienced visual hallucinations that occurred at spontaneous times. 

Fast forward to 1967, the term “Charles Bonnet Syndrome (CBS)” was introduced to the world by another Geneva native, George de Morsier.

CBS can be described as the presence of visual hallucinations among those with sight loss. These hallucinations are completely the product of visual impairments and are not signs of mental health deterioration. 

There are generally two main types of hallucinations experienced:

  • Simple patterns and shapes, like brickwork or mosaic
  • Complex images of people, landscapes, or objects

These will only affect a person’s sight. Smell, hearing, and touch will not be compromised. 

The reasons behind these hallucinations are not yet entirely clear. It is suggested that when sight loss occurs, the brain no longer receives as many signals from the eyes. It then attempts to make up for this lack of communication by creating its own. These end up translating into “phantom” images seen by the individual. 

CBS normally appears in the weeks and months following a big change in sight loss. Fortunately, for the majority of people, these hallucinations get less frequent with time, although reappearance of hallucinations five years after initially starting is a possibility. 

One of the most serious aspects of CBS is its unknown nature. Many people who begin experiencing hallucinations are often unaware of its true nature. This can cause fear for both the individual as well as their family and friends, due to visions being taken to be symptoms of mental health issues. 

Unfortunately, there is no direct way to diagnose the presence of CBS. Doctors will generally talk to the patient about their medical history and may carry out tests to rule out other causes for the visual hallucinations. 

Although no treatment is available, given enough time, CBS can improve over time. It has been found that often simply a better understanding of CBS can help patients cope better as they understand that it is purely a normal result of sight loss rather than anything to do with mental health. In some cases, medication for epilepsy, Parkinson’s Disease, and dementia have been able to help, but due to the possibility of severe side-effects, it is only recommended for those who are seriously affected and under supervision. 

There are, however, a few self-help methods that may relieve any hallucinations experienced:

  • Changing lighting conditions, i.e. making it brighter or dimmer
  • Scanning from left to right repeatedly without moving the head for 15 secs. This can be done 4 or 5 times if hallucination continues.
  • Staring at an image and blinking rapidly, or attempting to touch it. 
  • Performing a task that includes large movement, e.g. going to the kitchen to make coffee
  • Sleeping and resting well. Fatigue and stress may increase the likelihood of hallucinations.

Blind individuals experience new musical “& Juliet” with OXSIGHT glasses

Manchester, 9th September, 2019 — Registered blind individuals were given the opportunity to experience the new musical “& Juliet” in Manchester wearing new smart glasses that allowed them to see the entire performance.

Participants with ‘tunnel vision’ also known as ‘peripheral vision loss’ entered a competition to experience the show using new smart glasses technology which allowed them to see the entire musical “& Juliet” before its West End debut. In addition, a further 10 registered blind winners were given an exclusive touch tour which allowed them to feel the props, costumes and meet the cast – followed by the Opera house’s fantastic audio description accessibility option. 

Enjoying a behind the scenes experience on the touch tour

Enjoying a behind the scenes experience on the touch tour

Kevin Crompton, 48 from Manchester who has lost 95% of his vision and describes his remaining sight as “looking through pin hole”, commented on the performance “It was very emotional putting the glasses on for the first time in the theatre, usually I wouldn’t be able to see the stage, but I was able to follow the entire story and see the full stage and all of the characters. Sight loss doesn’t mean having to give up on life, it means doing life differently – this is exactly what OXSIGHT are doing for people”.   

OXSIGHT teamed up with Opera House Manchester and Henshaw’s to make theatre experiences more accessible for those living with a visual impairment and as part of the World Sight Day 2019 campaign, giving free tickets to new musical.

When we were asked to be involved our answer was a fervent yes. This is an opportunity where we can support developments in accessibility and change how people can experience live entertainment. Working with OXSIGHT means there’s a chance of breaking down barriers and we are committed to making theatre to be accessible to everyone”, said Manchester Opera House Director, Sheena Wrigley.

Winners settling in for a night at the theatre wearing OXSIGHT glasses

Winners settling in for a night at the theatre wearing OXSIGHT glasses

OXSIGHT users have experienced an increased field of view of up to 68 degrees. Many utilise the different modes on offer to enhance their remaining vision and experience sights they thought they had lost forever.

Kirsty Hill from Shrewsbury lost her peripheral vision following a stroke three years ago commented on her experience, “I can’t tell you how much the glasses mean to me, I never thought I would be able to enjoy anything like this properly again. The planning and care that went into looking after all of us and our dogs was so appreciated. The show was an opposite of sensory deprivation, still feel like my hair is standing on end!”  

There are more than two million people in the UK living with sight loss that noticeably affects their quality of life. In addition, it is estimated that 250 people start to lose their vision every day. 

Hayley Allen, OXSIGHT Customer Care Manager, said: “It’s great to be able to collaborate with Henshaw’s, who do such amazing and important work in supporting the visually impaired. And Opera House Manchester have been brilliant. They’re always working hard to ensure that the visually impaired community feel as welcome as possible.”

Guide dogs and their water bowls at Manchester Opera House

Guide dogs and their water bowls at Manchester Opera House

This theatre event marks the first of many partnerships that OXSIGHT and Henshaw’s will be seeking out in order to increase accessibility at cultural venues for the visually impaired community.

retinopathy of prematurity

Primer on Retinopathy of Prematurity

The World Health Organisation (WHO) estimates that over 15 million babies are born prematurely (generally agreed to be at less than 37 weeks) every year. This equates to 1.5 times the population of Belgium.

Premature babies are at an increased risk of complications due to the non-optimal gestation period afforded them. If blood vessels in the retina fail to develop fully, babies can be born with retinopathy of prematurity (ROP). 

The retina is responsible for taking light that enters the eye and converting it into signals for the brain to interpret. They are supplied with blood through an extensive network of blood vessels that start to develop 16 weeks into pregnancy. Normally, it takes the full term (40 weeks) for the blood vessels to fully develop.

If this process is interrupted, it can leave the retina short of the blood vessels it requires to function properly. In order to make up for this deficiency, it may stimulate new blood vessels to grow. However, these are often weak and can lead to scarring and damaging of the retina. Severe ROP can also lead to retinal detachment. 

In the UK, babies born under 32 weeks or at a weight of under 3lbs will be screened for potential ROP. Eye examinations will continue until the risk of needing treatment has passed. 

 

Retinopathy of prematurity can be described in 5 stages:

  • In stage 1, the new blood vessels have not started to grow and the mark between where blood vessels are present and not is flat. Usually recovery without treatment is possible at this stage. 
  • At stage 2, the mark between the two regions has become raised, but still no new blood vessels have begun to grow.  It is still possible to recover without treatment at this stage but regular checkups to monitor the condition are recommended. 
  • Stage 3 is normally characterised by the growth of new vessels. These vessels are weak and can lead to scarring which may cause sight problems. Treatment is normally required at this stage. 
  • The new vessels that grew have begun to shrink and cause scarring in stage 4. This may start to pull the retina away from the back of the eye. 
  • During stage 5 the retina has fully detached and this would lead to permanent sight loss. 

 

Treatment for retinopathy of prematurity most often involves the removal of the fragile new blood vessels that grow. This can be done with laser treatment, eye injections or cryotherapy. 

If retinal detachment has begun, the patient may require surgery to help hold the retina to the back of the eye. Unfortunately, this needs to be done early during stage 4. If the condition has progressed to stage 5, it is unlikely that useful vision can be salvaged. 

nutritional optic neuropathy

Primer on Nutritional Optic Neuropathy

A young boy, aged 17, made the news when he developed a form of blindness after years of malnourished dieting.

After examination, it was found that the teenager’s diet had given him nutritional optic neuropathy, a type of acquired optic neuropathy.

Optic neuropathy is when the optic nerve is damaged which can then lead to changes in the individual’s sight. This is due to damage done to the retinal ganglion cells and their axons which can cause modifications to the optic nerve head as well as the surrounding retinal nerve fibre layer.

Optic neuropathy can be caused by a variety of factors, including trauma, drugs, and genetics. Nutritional optic neuropathy occurs when the body is deficient in certain nutrients due to the individual’s diet.

Although those who develop this type of optic neuropathy solely due to nutritional malpractice are rare (they are more commonly found in regions where famine is prevalent), lacking certain nutrients is often a big factor in the progression of other forms of this condition.

Some of the main deficiencies responsible for nutritional optic neuropathy include:

  • Vitamin B-12 (cyanocobalamin)
  • Vitamin B-1 (thiamine)
  • Vitamins B-2 (riboflavin)
  • Folate

In the case of the teenager mentioned above, his diet consisted of chips, crisps, white bread, and sausages, which left his body in need of more vitamin B-12, among other nutrients.

In the early stages of nutritional optic neuropathy, visual acuity is normally the first to worsen. At this stage, if treated correctly, it is possible to reverse the detriment done and recover lost sight. If left untreated, patients can lose central vision as well as the ability to distinguish colours.

Damage can be permanent so it is important to seek clinical advice as soon as any change in sight is noticed so that treatment can start. An improvement in diet as well as vitamin supplements can help with staving off the later stages of the condition.

It must be noted that due to the rarity of primarily nutritional optic neuropathy in developed countries, the selectiveness of the diet could be a symptom of avoidant restrictive food intake disorder (ARFID), an eating disorder that is not due to body image issues.

eyes of a baby

Luxturna gene therapy for sight loss on the NHS

This week, the BBC reported that gene therapy may become available on the NHS for those with visual impairments. With a commercial price of £613,410 per person, the NHS have managed to come to an agreement with global drug company Novartis over treatment with voretigene neparvovec (commercially known as Luxturna) and it is expected that treatment will be available from January 2020.

Let’s go through the main points:

  • Eligibility for the treatment is very specific – Voretigene neparvovec is targeted at those with inherited retinal dystrophies due to a mutation in the RPE65 gene, which aids the production of proteins vital to normal vision. The National Institute for Health and Care Excellence (NICE) estimate that approximately 86 people in England will be eligible.
  • Voretigene neparvovec aims to stabilise vision and prevent further sight loss – Unfortunately the treatment does not aim to restore vision that has already been lost.
  • Location may be important – NICE lists NHS England as the only NHS consultee for the proposed treatment. Furthermore, in reports, quotes from the NHS have come from Simon Stevens, the CEO of NHS England. This could suggest that the treatment will only be available to those living in England and Wales (who are legally obliged to fund NICE guidance). Those with the condition in Scotland and Northern Ireland will have to wait on separate decisions to be made. Additionally, according to a statement by NHS England, the treatment will initially be rolled out in three national specialist centres across the UK. Making it available to other hospitals later is an option and not mandatory.
  • Injections in the eye – The treatment is administered by a one-time injection under the retina of each eye. Normally, one eye will be treated first, with the other treated after at least 6 days. The injections aim to introduce a healthy version of the RPE65 gene which can then help production of the protein needed for normal vision.
  • Long-term effects are unclear – Studies have shown shorter term benefits (3 to 4 years) but longer term effects are uncertain. However, clinical experts feel that there is a “biological rationale” for the effects of the treatment to remain.
  • There are side effects – As with most treatments, there are potential side effects and these can be found on Luxturna’s website. Some of the more serious ones include eye infections, permanent decline in visual acuity or sharpness of central vision, as well as further sight loss due to various potential changes to the eye.
  • Not set in stone – This treatment is still currently in progress with final evaluation determination expected to conclude by 20th September 2019. It is still a possibility (admittedly a minute one) that the availability of Luxturna could be delayed. However, the NICE guidance is expected to be published on the 9th October 2019, which then gives NHS England three months to make it available “as an option”.

Please see the NICE website for full details and status of the treatment.

Primer on Diabetic Retinopathy

If you pool everyone with diabetes together and form a nation, they would be the third most populous country in the world.

Those with diabetes will normally find that they have increased levels of glucose in their blood. This can lead to nerve and blood vessel damage as well as an increased risk of cancer due to DNA harm.

Although, not everyone with diabetes will experience sight loss, diabetics will have a higher risk of developing certain visual impairments, such as cataracts and glaucoma.

One of the more common ones is diabetic retinopathy.

This is when the increase in blood sugar levels affect blood vessels at the back of the eye. This interferes with how the retina work and can lead to retinal vessels leaking or bleeding.

 

There are 4 main stages of diabetic retinopathy:

1. Background Retinopathy

This is when capillaries in the retina weaken and develop small areas of swelling. This can lead to small amounts of bleeding as well as the leaking of a fluid called exudate. Although this will normally not affect vision, if it is left untreated the condition can become worse and cause the condition to the next stage.

 

2. Non-Proliferative Retinopathy

Here we see more drastic damage to the capillaries in the retina and usually occurs after years of high blood sugar levels. Bleeding and leaking is more prominent and blood vessels are weakened, potentially losing the ability to transport blood which can cause the retina to malform. Eventually, blood vessels may be completely blocked, which will prompt the body to release growth factors to encourage the formation of new vessels.

 

3. Proliferative Retinopathy 

By now, new blood vessels have been formed to help supply blood. However, they are weak and are prone to haemorrhaging and leaking. They can also grow on the retinal surface or inside the vitreous gel. When blood or fluid is leaked, this can damage the retina or block vision when inside the vitreous gel. Scarring can also occur and an increase in scar tissue can cause the retina to detach which may lead to serious sight loss.

 

4. Diabetic Maculopathy

The more common cause of serious sight loss, diabetic maculopathy can occur with or without proliferative retinopathy [Pipe, D.M. & Rapley, L.J. (2008). “Abnormal Ocular Conditions: A Handbook for Dispensing Opticians”]. It occurs when haemorrhaging or leaking involves the macular area of the eye and can cause central vision loss.

 

Symptoms of diabetic retinopathy may not occur at the beginning and can start to appear as the condition advances. Typical manifestations include:

  • Blurred vision
  • Dark spots or patches
  • Eye pain or redness
  • Reduction in night vision
  • Sudden sight loss

Treatment for diabetic retinopathy can depend on how far it has progressed. Laser surgery can be done on a localised area to help reduce swelling and seal up blood vessels. For larger affected areas, pan-retinal laser surgery can be used to shrink abnormal blood vessels and inhibit the release of growth factors. Vitrectomies are used to treat severe bleeding into the vitreous gel. Vitreous is removed and replaced with a clear salt solution to maintain the pressure in the eye.

However, these treatment methods are more aimed at preserving sight rather than restoring. As with many diseases, prevention is just as (if not more) important as treatment. Maintaining a manageable blood sugar level is key and this includes exercise, diet, and generally living a healthy lifestyle.

Primer on Mobility Canes

Mobility canes. Some call them “white canes”. Others prefer the phrase “symbol cane”. Then there are those who use the word “stick” instead.

Whatever the nomenclature, mobility canes are a recognisable representation of sight impairment.

However, due to the various sizes and design they can come in, people may be confused as to what the differences are and if they are meant to convey different meanings.

Fortunately for you, OXSIGHT have a handy little primer to guide you through the varieties and what they represent.

 

Size Matters

The Symbol Cane – These canes are the shortest of all canes and are not meant for physical support. They are carried around to notify others that the individual may have a visual impairment. Often made out of lightweight aluminium, symbol canes are often collapsable into three or four segments so they can be folded up and stored conveniently away.

The Guide Cane – The next size up from symbol canes are guide canes. These are normally held diagonally in front of you body and used for basic protection, like detecting obstacles such as steps or kerbs. Like symbol canes, they are normally collapsable for easy storage. They may require training to use competently.

The Long Cane – The largest size of cane is the long cane. These extend out and are used by those with limited or no vision to feel the layout of the environment. Again they are collapsable, however they are normally made-to-measure to ensure maximum functionality for each individual. Training is required in order to safely operate long canes.

The Support Cane – Shorter and thicker than long canes, the support cane is used as an aid by providing physical support. They may have a handle on one end and are strong enough to support body weight which means that they are often heavier than the other types of canes. The end of a support cane will generally grip the floor to ensure that it does not slip when in use.

 

Just The Tip

Due to their functional nature, tips on the ends of guide, long, and support canes can be customised based on preferences and intended use.

Some tips may hold an advantage indoors, while others may be more suited to rugged terrain. They come in different shapes and sizes, and more may be introduced in the future as cane technology is further optimised.

Here are some of the more common ones:

Pencil Tip – A thin, straight piece of plastic which slightly extends the length of the cane, pencil tips are used in conjunction with the two-point touch technique. They are extremely lightweight so will not stress the wrist as much. However, due to their size, they are prone to being snagged in cracks and other hazards so are not as suitable for rough terrain.

Marshmallow Tip – Imagine a marshmallow on the end of a stick and that’s what you have. Their larger size provides a greater surface area of contact between the tip and the surroundings. This provides more feedback for the user. They will be slightly heavier due to the increase in bulk.

Ball Tip – One more size up is the ball tip. They are great for beginners and are suited to heavy or extended use as they wear down slower. Constant contact techniques are preferred over two-point touch when using ball tips due to their weight potentially straining the wrist. Their size means users will get alot of feedback and they are very suitable for rough terrain.

Roller Tip – These tips can come in different shapes, such as marshmallow, ball, or disk. They are capable of rolling and so making constant contact techniques easier to do as well as minimise the amount of wear the tip takes. They are good for urban environments but may struggle in more unconventional settings.

Flex Tip – Shaped like a bell, the flex tip does exactly that. When sweeping from side to side, the bell end will bounce over uneven surfaces, making it less prone to snagging. It is specifically designed for rough outdoors use.

Rover Free Wheeling Tip – Perhaps the most heavy duty tip, the rover free wheeling tip is a soft rubberised wheel attached to the end of the cane. It is designed to be rolled forwards and backwards and help navigation over really rough terrain.

Bundu Basher Tip – This tip looks like the end of thin hockey stick and was initially designed to aid navigation through the bush in South Africa. It curves up at the end to prevent it from snagging on rough terrain.

 

Once You Go White…

White – The most traditional and widely used colour for mobility canes. Instantly recognisable as an indicator of visual impairment.

Red Stripes – Often seen on top of white coloured canes, these red stripes indicate that the user also has a hearing impairment in addition to their sight loss.

Any other colour – Although non-traditional, it is possible to purchase canes in other colours. While they will not have the immediate effect of informing others of a visual impairment, they enable the user to display their own personality.

Glow in the dark – Mainly for navigation at night, these canes will not only help the user but also those around them as they can indicate where the user is. Usually, these canes do not require batteries as they will charge up in direct sunlight during the day.

Deafblind UK and OXSIGHT work in partnership to give people their sight back

Original post by Deafblind UK.


National charity, Deafblind UK, has announced a partnership with OXSIGHT, the provider of high-tech glasses that can give people with visual impairments their sight back.

The partnership sees the two organisations working closely together with the common goal of enhancing the lives of people living with sight loss. Steve Conway, CEO of Deafblind UK said: “Losing your sight can be devastating but even more so when your hearing is also impaired, and you are unable to rely on audio communications. That’s why OXSIGHT’s products are even more important to people who are deafblind.”

OXSIGHT glasses expand the field of vision for people with peripheral sight loss caused by conditions such as Glaucoma, Diabetes, Retinitis Pigmentosa, and other degenerative eye diseases. OXSIGHT are leading the way in the development of digital technology and they are building a strong pipeline of products to help those with a whole range of conditions including central vision.

Deafblind UK’s Chairman Bob Nolan uses the glasses. He said: “The moment when I first tried on the OXSIGHT glasses will stay with me for a long time. I was talking with one of my family members and I could only make out her head and shoulders in a dimly lit room. When I put the glasses on I could clearly see not one but five members of my family! When you have less than five degrees of vision as I do, looking through the glasses is nothing short of miraculous.”

Deafblind UK is a national charity supporting people with sight and hearing loss. As part of the partnership, OXSIGHT will hold monthly clinics at Deafblind UK’s office in Peterborough, where those with peripheral sight loss can book an appointment to try a pair of glasses. For every pair of glasses sold as a result of the clinic, OXSIGHT will make a donation to Deafblind UK.

Steve Conway, CEO of Deafblind UK said: “This is a fantastic example of a charity and a technology company coming together with a mutual interest to support people who are deafblind. The success stories that we have heard so far are incredible; people who haven’t seen their partner or children for years can suddenly see the world around them again. This really is life changing technology and I am proud to be a part of it.”

Rammy Arafa from OXSIGHT has been working with Deafblind UK to set up the partnership. He said: “I am delighted to be able to work so closely with Deafblind UK. They work so hard to support people with sight and hearing loss and our product will complement their existing service offering. If, by working together, we can help some of Deafblind UK’s members to see again then it’s a worthwhile venture.”

OXSIGHT clinics will take place at Deafblind UK’s office on: 21st August, 23rd October, 20th November, 18th December, 22nd January, 26th February, 25th March. For anyone interested in booking an appointment at the clinic, please complete an online form at www.oxsight.co.uk/consent. OXSIGHT registered opticians will then review your individual condition and let you know whether you are suitable to try the glasses.

Smoking and Sight Loss

The act of smoking is normally associated with a trip to the doctor’s and the subsequent discovery of cancerous cells in and around the lung region.

However, amongst the myriad of ailments smoking can cause lies vision loss.

Toxins inhaled into the body through smoking can help contribute to occurrences of vasoconstriction, reduced oxygen availability, and chronic inflammation. In addition, smoking increases the number of oxidative radicals in the body and lowers the level of antioxidants. This results in a ramp up of the body’s aging process.

However, due to the sheer amount of harmful chemicals there are in tobacco, harm is not limited to just internal. Smoke from tobacco contain ash particles and these can physically come in contact with the eye, causing harm.

This means that ocular distress from smoking is not just limited to those that actively take part in it. Bystanders within the smoker’s area of influence may also be subject to some of the harmful effects.

Here are some of the most common eye conditions associated with smoking:

 

Cataracts

Smokers will inhale heavy metals, including cadmium, iron, lead, and copper. These can accumulate in the lens of the eyes and cause damage.  Oxidative radicals can also cause changes to the lens structure and composition, contributing to the formation of cataracts, which is a clouding of the lens in the eye.

 

Age-related Macular Degeneration (AMD)

AMD is one of the leading causes of sight loss in the UK and smoking is one of the factors why. Those that smoke can be at increased risk due to the numerous toxins present. Tar from cigarettes can also help the formations of drusens, which are fatty deposits in the retina.

Those who already have signs of AMD may find that the condition progresses faster if they are smokers.

 

Graves’ Ophthalmopathy 

Graves’ ophthalmology, also known as thyroid eye disease (TED), occurs mostly amongst individuals with Graves’ disease, an autoimmune disease that impacts the thyroid.

Smoking can affect the thyroid gland and prevent the uptake of iodine as well as negatively impact the sympathetic nervous system which can then affect thyroid function. According to studies, smokers with Graves’ disease are at least twice as like to develop TED, with the probability increasing up to eight times for those that heavily engage in smoking.

Due to treatment methods often involving consumption of iodine, smoking can also reduce the efficacy of therapy, making it even harder to recover from.

 

Dry Eyes

Dry eye is most commonly caused by one or more glands in the lids reducing in function. This can be caused by blockages in those glands which causes more friction on the front surface of the eye. In some cases, the eyes will water profusely because the eye believes it is dry so it secretes more fluid. However, because there are three layers to the tears, if one is not functioning properly then the tear may not be able to relieve the dryness.

Although not as serious as the other conditions listed, dry eyes can be made worse due to smokers experiencing reduced tear production. If left untreated, this can lead to a variety of complications with the individual’s cornea.

Primer on Stroke-related Vision Loss

You push open the heavy oak doors of the pub and are instantly hit with a barrage of jovial sounds mixed with the scent of a strong alcohol and sweat cocktail. 

Scanning round the establishment, you quickly locate your friends and make your way to the empty seat left, you presume, for you. 

And then the drinks start. 

After a few rounds or more, you start to notice a numbing sensation on the left side of your body. Your friends comment on how your left eye and mouth are drooping. You try to say that something seems wrong, but it all sounds garbled and nonsensical.

At first, you blame it on the alcohol, but then you realise that you can no longer move your left arm. You start panicking. 

You’re having a stroke. 

The next thing you remember is waking up in a hospital room. It’s dark and you’re alone. 

You mentally check over yourself. Arm works. Face seems to be as expressive as ever. Mental calculations are tough, but you were never good at them anyway. Words sound clear enough. 

Footsteps gradually increase in volume and you realise that they are coming to you. 

You quickly close your eyes as light suddenly invade your eyes. As you become accustomed, you tentatively open your eyes. 

But you can only see half of what you would normally see. 

One side of your vision is gone.

 

Strokes occur when a part of the brain is deprived of oxygen. It is life threatening and can leave the victim/survivor with a series of conditions, ranging from mental to physical to cognitive. 

There are also various visual problems that can arise. Here are some of the most common stroke related sight loss conditions.  

 

Visual field loss

This is when parts of vision is lost. Hemianopia is when one half of vision is gone so those with the condition will only be able to see either the left or right half of what they are looking at. 

It is also possible to lose central vision, which may mean that it is not possible to directly look at something. 

 

Eye movement complications

Strokes can affect a victim’s control over their eyes. This may mean that the eyes are unable to coordinate with each other, which can cause diplopia (double vision). 

Some may also experience an uncontrollable wobble of the eyes (nystagmus) which can result in reading difficulties. 

 

Trouble with visual processing

Strokes can disrupt the way information is passed from the eyes to the brain and how that is processed. This miscommunication can often result in visual neglect, which is when something that is seen is not processed and therefore does not register with the individual. You may find that these individuals will unintentionally ignore people or objects because their brain has not interpreted the data sent by the eyes. 

The other extreme is also possible as many will experience hallucinations caused by processing errors by the brain, giving them images of things that aren’t actually there. 

 

Due to the wide range of visual conditions suffered by stroke victims, there is no one-fix-for-all. Treatment can help the victim cope and adapt to their vision loss, and can come in the form of rehabilitation, accessories, or smart glasses, depending on the exact nature of their condition. 

Some people will find that their vision improves for up to 6 months after their stroke. But again this depends on how well their brain heals after the initial damage.