Characterising eye movement dysfunction in ME/CFS

[Firestormm]

2013 Aug 6. [Epub ahead of print]

Characterising eye movement dysfunction in myalgic encephalomyelitis/chronic fatigue syndrome.

Abstract

Background:

People who suffer from myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) often report that their eye movements are sluggish and that they have difficulties tracking moving objects. However, descriptions of these visual problems are based solely on patients' self-reports of their subjective visual experiences, and there is a distinct lack of empirical evidence to objectively verify their claims. This paper presents the first experimental research to objectively examine eye movements in those suffering from ME/CFS.

Methods:

Patients were assessed for ME/CFS symptoms and were compared to age, gender, and education matched controls for their ability to generate saccades and smooth pursuit eye movements.

Results:

Patients and controls exhibited similar error rates and saccade latencies (response times) on prosaccade and antisaccade tasks. Patients showed relatively intact ability to accurately fixate the target (prosaccades), but were impaired when required to focus accurately in a specific position opposite the target (antisaccades). Patients were most markedly impaired when required to direct their gaze as closely as possible to a smoothly moving target (smooth pursuit).

Conclusions:

It is hypothesised that the effects of ME/CFS can be overcome briefly for completion of saccades, but that continuous pursuit activity (accurately tracking a moving object), even for a short time period, highlights dysfunctional eye movement behaviour in ME/CFS patients. Future smooth pursuit research may elucidate and improve diagnosis of ME/CFS.

ME Research UK

RESEARCH UPDATE – Eye Movement Dysfunction - 20 August 2013

Problems with eyes and vision are common in people with ME/CFS – yet there is very little formal evidence in the scientific literature that visual symptoms actually exist. To redress the balance, the Vision and Language Research Group, University of Leicester – with funding from ME Research UK and the Irish ME Trust – has been trying to identify and quantify vision-related problems in the disease.

The group published the first scientific paper on its findings several months ago – read our essay here http://bit.ly/17ZXP08 – and a second report has now appeared http://1.usa.gov/1bPaC9W, specifically on eye movements. The experiments measured cognitive speed (http://bit.ly/155jF4B), and eye movement tracking during ‘smooth pursuit’ of a slowly moving object (http://bit.ly/14SOa9O) and during reflexive (prosaccade) and inhibitory (antisaccade) (http://bit.ly/14xZhpw) movements to visual targets on screen.

Although the ME/CFS patients and matched controls (20 in each group) were similar in many respects, patients generally performed worse than controls in tasks that required quick and accurate eye movements. In particular, the ability to perform eye movements opposite a target (antisaccades) was more impaired in ME/CFS patients than controls, particularly for positional errors. In addition, patients were deficient in their ability to track closely a moving target during ‘smooth pursuit’, and their performance deteriorated as the testing session went on, something not seen in the healthy people. As the authors point out, it may be that patients are susceptible to fatigue even at these very short timescales – the ‘smooth pursuit’ requires sustained musculature activity for 30 seconds, and the 3 test-runs take only 5–10 minutes.

Intriguingly, the visual deficits seemed to be related to age in the ME/CFS patients but not in the healthy people, suggesting that older adults with the illness are less able than young adults to compensate for ME/CFS-related vision deficits. In fact, the overall disease impact may be proportionately greater in older ME/CFS patients, as a recent ME Research UK-funded report has also suggested http://bit.ly/1cXegCy.

 

[Sean]

Is accurately tracking a moving object the same problem as accurately tracking text?

I have serious (and increasing) trouble getting my eyes to consistently follow text, especially large unbroken blocks of text, which look more like a page of tiny squiggling worms to me.

 

[Firestormm]

Is accurately tracking a moving object the same problem as accurately tracking text?

I have serious (and increasing) trouble getting my eyes to consistently follow text, especially large unbroken blocks of text, which look more like a page of tiny squiggling worms to me.

With me it appears as a blur a lot of the time. Thank god for pdf. viewer and things. I remember at Uni I had all this stuff installed to help me read (or for text to be read out). It did help with my comprehension too of course. And that's something else - if you are struggling to read you struggle even more to understand.

Certainly not eyesight I don't think - some processing problem. I haven't properly absorbed the above yet.

 

[user9876]

With me it appears as a blur a lot of the time. Thank god for pdf. viewer and things. I remember at Uni I had all this stuff installed to help me read (or for text to be read out). It did help with my comprehension too of course. And that's something else - if you are struggling to read you struggle even more to understand.

Certainly not eyesight I don't think - some processing problem. I haven't properly absorbed the above yet.

There are a number of psycholinquistic experiments where they follow eye movements to get an understanding about how people comprehend language. They look for things such as rereading of bits of a sentence and timings for reading different types of clauses. These types of things might be interesting in looking at issues with blocks of text and processing problems.

 

[rosie26]

I have big focus problems when it comes to movement around me, it makes me feel off balance, sick.

Changes in space, like walking in a narrow hall then entering into a high ceiling large building, I find I have to stop and steady myself to adjust.

Also I can't watch tv programmes where they flick quickly from one scene to the next. I can't focus, process quickly enough. It really hurts my eyes. Have to turn the tv off or change channel.

 

[xxRinxx]

I've had numerous eye tests with interesting results. They did the eye-tracking test that made me focus as I tried to lie down, and my eyes 'spazzed' out, AKA, they started that rapid eye movement tracking and basically just couldn't focus on her finger.
Also, I had an Epilepsy test, that while I'm not quite Epileptic, i had 'Epileptic-like- results. My eyes couldn't dilate correctly and it made me start hyperventilate so bad they ended the test early. White lights, yellow, and any in that light spectrum I can't tolerate. Blue, darker reds, and green flashes don't bother me as bad.
I encourage more ME/CFS patients to get an Epilepsy test if only to document if these kind of results are usual for us.

 

[Little Bluestem]

Dr. Cheney considers ME/CFS a minor seizure disorder, or did at one time.

 

[Legendrew]

Interesting to see people looking into the lesser reported ME symptoms - I for one certainly have issues with blurring vision and difficult focusing on objects during times when all my other symptoms are worse. It'd be interesting to see further studies - i'm specifically interested to read the effects appear to be intensified in older patients but I think it's too early to speculate as to why this many be.
(Maybe that's why playing videogames, watching TV and using the computer for too long these days makes me feel so ill.)

 

[Nielk]

Interesting to see people looking into the lesser reported ME symptoms - I for one certainly have issues with blurring vision and difficult focusing on objects during times when all my other symptoms are worse. It'd be interesting to see further studies - i'm specifically interested to read the effects appear to be intensified in older patients but I think it's too early to speculate as to why this many be.
(Maybe that's why playing videogames, watching TV and using the computer for too long these days makes me feel so ill.)

What else is there left then to do?

 

[Legendrew]

What else is there left then to do?

I don't know =(

As for this data i'd have to say that now replication is the name of the game
If this is a common feature, it could be very good for diagnosis; i've never been a fan of the crazy 2 day exercise tests many researchers are working on.

 

[MeSci]

I have had episodes of several distinct visual abnormalities since getting ME. One has only occurred twice and seems to be a kind of scintillating scotoma. That was really weird, with everything outside the central visual field shimmering, and I self-tested for stroke both times (negative, thank goodness). It lasted about 15-30 minutes then disappeared completely. I could not read at all, or see a screen properly, during the episodes.

More common is what appears to be nystagmus, which sounds like what several people here are describing, when you can't see properly because your visual focus is jumping all over the place, and it's due to involuntary erratic movements of the eye muscles. I think I have it more when I also have post-exertional twitching in my leg muscles.

I just looked in Erica Verrillo's Guide to CFS and found several references to nystagmus, and indeed a paragraph on it, where it says among other things

Dr. Alfredo Sadun, a neuro-ophthalmologist at the University of Southern California, has observed nystagmus (small, rapid eye movements) in one fourth of patients with CFS/ ME.

I had it this morning, and have been trying to think of a way to describe it. It's not blurred vision in that things are not hazy or swimming. This morning I thought "My vision has gone wobbly again!" and that seems more accurate.

 

[Legendrew]

In terms of eyes, about ten minutes following the vaccination which triggered ME off for me I was walking home from my GP clinic and all my vision faded to black and white and I had to sit down on a grassy area as I had no energy to continue and stayed there for ten minutes before I could continue. I've never really mentioned it to anyone as I never knew what anyone would make of it but since we're talking about eyes and vision I thought why not.

 

[cfsme23]

Oh cool, I was a student at the University of Leicester when I took part in this research. I am pleased it has seen the light of day (pun intended)

 

[rosie26]

In terms of eyes, about ten minutes following the vaccination which triggered ME off for me I was walking home from my GP clinic and all my vision faded to black and white and I had to sit down on a grassy area as I had no energy to continue and stayed there for ten minutes before I could continue. I've never really mentioned it to anyone as I never knew what anyone would make of it but since we're talking about eyes and vision I thought why not.

Unpleasant experience for you Legendrew. ! Sounds like a sensitive reaction to the vaccine. Sound close to a black out ?

I had to get a tetanus jab about 6 years into my ME, I was very nervous about having it, but I had too as I had stood on a old rusty garden fork. Fortunately I had no problems with the tetanus injection. But I noticed they made me wait in the waiting room for 20 minutes after having the jab just in case of a reaction. So good idea to sit there in the waiting room even if they don't tell you too.

I wonder what vaccine it was that you had ?

 

[Legendrew]

Unpleasant experience for you Legendrew. ! Sounds like a sensitive reaction to the vaccine. Sound close to a black out ?

I had to get a tetanus jab about 6 years into my ME, I was very nervous about having it, but I had too as I had stood on a old rusty garden fork. Fortunately I had no problems with the tetanus injection. But I noticed they made me wait in the waiting room for 20 minutes after having the jab just in case of a reaction. So good idea to sit there in the waiting room even if they don't tell you too.

I wonder what vaccine it was that you had ?

Yeah I guess it was a sort of black out on reflection. I had MMR and tetanus at the same time so I don't know which it was or if it was both together. Not something i'd ever wish to experience again though! Thinking about it like that I guess its not really the same thing as the thread is discussing but as i've already said I get the blurred vision sometimes and difficult concentrating.

 

[Firestormm]

Taken from here comment #450

Prof. Jonathan Edwards:

"The eye movement study looks like something very well worth repeating. It sounds like just the sort of thing that might produce an objective biomarker of neurological dysfunction. Hot off the press by the looks of things."

 

[Firestormm]

There are a number of psycholinquistic experiments where they follow eye movements to get an understanding about how people comprehend language. They look for things such as rereading of bits of a sentence and timings for reading different types of clauses. These types of things might be interesting in looking at issues with blocks of text and processing problems.

I wonder how tests for dyslexia might reveal some problems with this kind of processing ability (or lack of) that we are talking about? Funny that before Uni (I was tested only at Uni), and before I retired with ME, I had no problems of this sort: but when tested at Uni I was found to be 'borderline positive' for dyslexia. Consequently, and because of my ME, I was able to take my exams on computer: much more amenable to me than trying to absorb, think, and write with a pen: just about

Maybe eye-movement doesn't imply issues with processing? Maybe dyslexia tests are not revealing something that is connected? Just seemed that way to me. Doesn't matter if it's a novel, a science paper, something relating to the work I do, a magazine, or reading things on the forum: my 'eyes' and the interpretation, then attempts to regurgitate and re-interpret meaningfully: are all now affected. But it varies - could this be due to fatigue? Am I worse when more tired? Possibly but certainly not always... No I would say that it is part of the 'cognitive dysfunction' more generally.

Interesting. Remember that experiment with playing cards inside an MRI? That struck a cord with me. Not been able to locate it - if you can would you mind posting? Thanks in advance

 

[Rrrr]

I just posted this on another thread but will put here too.

SUMMARY OF VIRUS IN VESTIBULAR: MOST IMPORTANT LINKS.

Vision distortions are very very common with ME/CFS. Some doctors think this vision distortion (vestibular issues) are from viruses in our vestibular ganglion. Specifically herpes viruses. So the treatment is to take antivirals, such as l-lysine, acyclovir, famvir or valtrex. See below. (If I am not allowed to include links, please let me know.)

1. http://www.tampabayhearing.com/vestibularneuritis

2. Evidence for a viral neuropathy in recurrent vertigo., Gacek, Richard R. , ORL J Otorhinolaryngol Relat Spec, 2008, Volume 70, Issue 1, p.6-14; discussion 14-5, (2008)

3. A Perspective on Recurrent Vertigo, Gacek, Richard, ORL J, 2013; 75:91-107 http://www.karger.com/Article/PDF/348710

4. publications by Dr. Mitsuo Shichinohe, M.D., PhD
http://shichinohe.web.fc2.com/english1.htm
http://rlovell.tripod.com/Acyclovir.pdf

5. http://www.ncbi.nlm.nih.gov/pubmed/19142031
ORL J Otorhinolaryngol Relat Spec. 2009 Jan 10;71(2):78-86.
Ménière's Disease Is a Viral Neuropathy.
Gacek RR.
Department of Otolaryngology - Head and Neck Surgery, University of Massachusetts Medical School, Worcester, Mass., USA.
Morphological and clinical evidence supports a viral neuropathy in Ménière's disease (MD). Quantitative examination of 11 sectioned temporal bones (TBs) from 8 patients with a history of MD revealed a significant loss of vestibular ganglion cells in both the endolymph hydropic (EH) and non-EH ears. Transmission electron microscopy of vestibular ganglion cells excised from a patient with MD revealed viral particles enclosed in transport vesicles. Antiviral treatment controlled vertigo in 73 of 86 patients with vestibular neuronitis (85%) and 32 of 35 patients with MD (91%). Copyright © 209 S. Karger AG, Basel.

6. http://menieresjourney.blogspot.com/2012/04/acyclovir-famciclovir-l-lysine-can-anti.html
blog on antiviral and meniere's disease

Here is another thought: vision disturbances could be from an autoimmune condition:Meniere's disease might be an autoimmune condition?
http://www.sciencedirect.com/science/article/pii/S1568997212000092

 

[Snow Leopard]

I hadn't seen this eye stuff before. I suffer from constant eye pain these days and I wonder whether it is that I overcompensate for the aforementioned defects, causing extra eye strain/fatigue/pain?

 

[MeSci]

@Rrrr, as I said in the other thread, your links seem to be about ear - not eye - problems. I don't have time to look at the links in detail.