A patient is having their vision tested at an optical practice.

Measurement of visual function in infantile nystagmus: a systematic review

As a member of NUKE, the Nystagmus UK Eye Research group, the Nystagmus Network is delighted to see the publication of a literature review of functional vision testing for Infantile (Congenital) Nystagmus. The authors are Bader Almagren, NUKE and Matt Dunn.

NUKE sees this as a step towards establishing vision testing in cases of nystagmus which more closely measures what people living with the condition actually see.

Read the full article online at the BMJ/BJO here

Background/aims Recent work has called into question the ability of visual acuity (VA) to accurately represent changes in visual function in infantile nystagmus (IN). This systematic review investigated factors affecting visual performance in IN, to guide development of suitable alternatives to VA.

Methods Included studies used an experimental manipulation to assess changes in visual function in people with IN. Interventional studies, case series and case studies were excluded. Six databases were searched in August 2023. Selection, detection, attrition and measurement bias were assessed. Due to heterogeneous methodologies, narrative synthesis was undertaken.

Results Eighteen relevant papers were identified, 11 of which complied with the review criteria. Articles were grouped according to the factor manipulated to evoke within-participant changes in performance (motion blur, psychological state, gaze angle or visual crowding). Optotype, image, grating and moving stimuli have been employed under varying lighting conditions and exposure duration.

Conclusion Several factors affecting visual performance should be considered when assessing visual function in IN. While maximum VA is a useful metric, its measurement deliberately minimises nystagmus-specific factors such as changes in visual performance with gaze angle and the ‘slow to see’ phenomenon. Maximum VA can be measured using the null zone, providing unlimited viewing time, reducing stress/mental load and minimising visual crowding. Gaze-dependent functional vision space is a promising measure which quantifies the impact of the null zone but does not consider temporal vision. Although no complete measurement technique has yet been proven, this review provides insights to guide future work towards development of appropriate methods.

The logo of the University of Plymouth.

Research participation opportunity in Plymouth

Perceptual Learning for Nystagmus

We are delighted to offer people who have nystagmus the opportunity to take part in an exciting new research study at the University of Plymouth, in collaboration with Cardiff University and jointly funded by the Nystagmus Network and Fight for Sight.

Who are we looking for?

Anyone aged between 18 and 35, diagnosed with Infantile (Congenital) Nystagmus

What will you be doing?

  • Complete vision tests on computer at the University of Plymouth to assess how well you can see static and moving letters and static dots
  • Complete vision training at home for 1 hour per day, 3 days a week over a period of 4 weeks

Who are we?

Dr Mahesh Joshi

Dr Mahesh Joshi

Dr Asma Zahidi

Dr Asma Zahidi

For more information, please contact: [email protected] or [email protected]

Travel Expenses

We will be paying your travel expenses to Plymouth up to £50.

a blurred image of busy outdoor scene with lots of people milling around

Living with nystagmus through a global pandemic

Learning to live with nystagmus, finding our way in the world and developing independence creates a range of challenges as we move through the stages of life. Whether we’re talking about an everyday experience or the bigger and more stressful events we face, we all need a certain amount of resilience.

There’s a balance to strike between knowing when to seek or accept support and when to resist. Having someone help you may be the easy way, but we also need to hold on to our independence, develop self-confidence and learn new skills.

The dictionary describes resilience as “the capacity to recover quickly from difficulties; toughness”. Ultimately, it’s something that’s developed through the challenges we face in our lives, often learnt from the things that might not go as well as we’d hoped. Misjudging a step, being misunderstood because we’re not looking someone in the eye, struggling to see a train departure board or a menu, all these build our resilience and that’s not diminished when we choose to ask for help.

The challenges of this last year have added an additional level to our need for resilience. Familiar routines and networks have been removed with the loss of many of the vital distractions, the random meetings, the events to look forward to. In addition, we’ve been bombarded with often unhelpful news tugging emotional strings, loosening attachment to normal life and adding levels of fear and uncertainty.

So, what can we do to retain or renew our resilience?

I’ve tried to keep perspective and challenge fear inducing messages.

Daily walks have been important for physical and mental health and have also meant that I’ve guarded against having to relearn basic mobility skills or redevelop the confidence to get out independently again when things return to normal.

I also think having hope is important, having plans for when this is all over, buying tickets for shows, planning a family get together or meeting with friends.

Personally, I find sport great for building resilience, keeping running when you really want to stop, not being disheartened by the disappointment of a defeat or an unlucky net chord in tennis or a bad decision from an official. 

Sometimes we face bigger challenges: ill health, loss of loved ones, struggles to make ends meet or to find employment. It can feel that nothing has fully prepared us for these and yet learnt resilience can still help. Perhaps a capacity to accept our vulnerability can help the development of resilience, freeing us to accept support where we need it.    

Improving the infantile nystagmus test

Delegates at 100% Optical learned about progress on refining the way an eye movement disorder is identified in babies

Professor Jon Erichsen from the University of Cardiff gave a presentation on infantile nystagmus to eye care professionals at the recent 100% Optical event (ExCeL London, 25–27 January).  

Professor Erichsen highlighted that in the condition there are several “known unknowns.”

“One thing we don’t understand is why we can have all sorts of conditions where the nystagmus is the same even though the disease is different,” he elaborated.

He added that while treatments for nystagmus attempt to dampen oscillation in order to improve vision, it is still uncertain whether abnormal eye movements affect visual acuity.

Patients with infantile nystagmus see the world as stable despite their involuntary eye movements, Professor Erichsen shared.

Experiments aimed at assessing a patient’s visual acuity in the absence of involuntary eye movements came to a surprising conclusion.

“Acuity in the absence of visual motion is unchanged,” Professor Erichsen highlighted.

To illustrate this point, he shared the case of a patient with infantile nystagmus who received surgery that dampened her eye movements.

“By reducing eye movements, what we may be doing is increasing the contrast sensitivity function which is why patients are reporting that their vision is better” University of Cardiff’s Professor Jonathan Erichsen 

The patient reported being able to see better, although objective measures of her visual acuity had not changed.

Professor Erichsen shared that contrast sensitivity rather than visual acuity may be a better way of assessing treatments in infantile nystagmus.

“By reducing eye movements, what we may be doing is increasing the contrast sensitivity function which is why patients are reporting that their vision is better without the movements,” Professor Erichsen observed.

Read the full report on Professor Erichsen’s presentation in Optometry Today, here.

A young child's eyes.

How well will my child see?

Researchers from the University of Leicester have identified a new way of predicting the future vision of children with infantile nystagmus. The research, published in the journal Ophthalmology has developed a grading system for retinal development in infants and young children with the condition, providing an important tool for ophthalmologists to determine their future vision.

This new research, funded by Fight for Sight and the Nystagmus Network, highlights for the first time that we can use this existing grading system to predict future vision in children and infants with nystagmus. Importantly, it is more reliable than the current tests used.

Infantile nystagmus is a condition of involuntary (or voluntary, in some cases) eye movement, acquired in infancy or later in life, that may result in reduced or limited vision. It affects approximately one in 500 people. Due to the involuntary movement of the eye, it has also been called “wobbly eyes”, and often comes with a negative social stigma.

Nystagmus can be challenging to diagnose in children and often the level of sight loss a newly diagnosed child will experience is unclear, leading to significant anxiety for parents who fear their child will develop severe visual impairment.

With the advent of hand-held optical coherence tomography (OCT) – a non-invasive imaging test that uses light waves to take cross-sectional images of the retina – healthcare professionals are now able to obtain detailed information about the status of retinal development in young children and infants. These scans can be obtained in a few minutes and can be performed non-invasively in children.

In 2011, lead researcher, Dr Mervyn Thomas, had developed a grading system based on optical coherence tomography (OCT) for arrested retinal development and found that this system is able accurately to predict the prognosis of vision in children and adults with arrested retinal development.

Dr Mervyn Thomas, said “This study required a lot of patience and cooperation from our nystagmus patients and families. The result is now we have a validated method of predicting prognosis in children and infants with infantile nystagmus. This will allow clinicians to plan better for patients whose vision is likely to be worst affected by nystagmus, while also helping to reassure and enable patients and families to optimise the development and educational attainment of the child during this crucial, formative stage.”

Fight for Sight’s Head of Research and Policy, Dr Rubina Ahmed, said “This grading system is a positive step towards better care for children with infantile nystagmus and will help to allay concerns of parents with unanswered questions related to visual development and prognosis for their children and may in future lead to better care plans for individuals.”

Sue Ricketts, Executive Information and Development Manager at Nystagmus Network, said “This development highlights the importance of research investment in nystagmus diagnostics and also answers the question most parents of newly diagnosed babies have: How well will my child be able to see?”

This research was jointly funded by Fight for Sight and Nystagmus Network via the Small Grant Award, awarded to Dr Mervyn Thomas and Professor Irene Gottlob.