HELP- visual problems only when driving

Hi All

I’m not only new to forums but also to MS. I had my first epsiode in July last year with total numbness which affected my whole body. An MRI scan confirmed that it was MS. At the time because my symptoms were only sensory I was given a good prognosis and told that everything would resume to normal within the next couple of weeks/months and because of my age (35) and gender (female) the prognosis looked positive. However I waited 6 months and although most of my sensory functions came back my right hand still remained numb (I think it’s there for good now). Anyway to cut a long story short 8 months on and I have had another relapse - Sensory again only this time it’s just my right side and the tips of my fingers on my left hand. It started 3 weeks ago and I have received good support from my MS nurse and I am waiting for a Specialist appointment to discus DMD. Anyway that’s enough of the background info what I really would like your help and advice on is a problem I am having with my vision. It started a couple of weeks ago whilst everything was begininng to recover normally (apart from my hand but enough said on that), I began to develop a loss of hearing (which I suspected was caused by a cold infection). Anyway on Tuesday of this week I was driving home from work and noticed that my eyesight was considerably distorted and I was having trouble focusing, so much that I couldn’t make out if how many cars were in front of me as there appeared to be more than one car (it was a country road and daylight). I found that the only way to see clearly was to close one eye. I visited the GP on Thursday and told him about my ear - a viral infection that will have to clear on its own and asked if it was somehow affecting my eyesight, he told me he didn’t think so and to get my eyes tested, which I did the very same day. I told the optician I had MS and about my symptoms. She did a very thorough exam and found that my left distance vision had deteriorated since my previous test 2 years ago ( I also have an astigmatism in this eye). I passed all the other tests including the peripheral vision test) and she could not find any other problems - she even took photos inside my eyes and the nerves were all healthy. However because my left eye SPH has changed from +2.25 to +1.25 she has told me that she is referring me to an eye specialist through my GP and to hold back on getting lenses with the prescription she has given me. So after this long winded blog (not sure if that’s the technical term) I was wondering if anyone has any advice on:

  1. Can visual problems in MS only occur when driving? 2. Is it normal to be referred to an eye specialist with only a slight change after 2 Years? 3. Do you think this is just a normal distance vision thing that will be corrected by getting a new prescription? I am tempted to just order them online because I can’t drive without any corrective lenses and it will take ages for an eye hospital appointment. Any help or if anyone has any similar experience I would value your input. Katsxx

Hi Kats, I can’t answer your question, but be very careful about driving whilst waiting for your appointment. You could invalidate your insurance. Might be worth a call to your insurer to check. Hope you get a quick appointment. Shuffler

Thanks Shuffler, thanks for the advice I have already informed DVLA (have a 3year licence) and my insurance company know, they weren’t interested im my symptons just that I had MS (am expecting my premiums to go up at renewal). I’m not really convinced it’s anything to do with MS - but it seems as soon as you disclose to anyone you have MS this appears to be the reason for all health/sight problems. It’s probably just myopia which “normal people” have!!


Hi , visual problems are likely with MS , it can affect us all in different ways though , I mean as to what you can or can’t see , and when , even the heat or cold can affect it ,

It’s normal to get a referral (in my experience ) , and I bet you probably won’t have to wait long to see a specialist eye Dr , generally the hospital equiptment is more powerful than the opticians so it’ll be worth getting it checked out for a second time,

Optic neuritis is the main concern with MS I think , though my symptoms of that were loss of vision in one eye as opposed to blurring , hope I’ve been “some” help

OK, Kats, lets try and answer the questions.

1- It is most unlikely that any vision problem caused by MS would only be there when driving. Most likely, you are not looking at the right things to notice any problem.

2- I am tempted to suggest that the optometrist is passing the buck (but I am not an optometrist, please not). There are a few bits that you have left out, and somethings that do not quite add up.
I will guess that you are somewhere between mid-30s and mid-40s, and have short sight.
From the test results above, it looks like your distance vision - in one eye -has actually improved, so that your present glasses are really too powerful. This does tend to happen at around that age. Add in any astigmatism, and there could be a substantial change in the way your old prescription works for you.

3- A question for you first: Was there any mention of “prism” on your prescription. If there was, this could suggest something different (and probably MS influenced) is going on. Here is how it works:
For good vision, the eye muscles must focus the light correctly onto the retina (The back of the eye) and both eyes must align the point of sharp focus to the same place in each eye. If this last bit does not happen, you are heading down the road to double vision (with the two eyes fighting each other). Closing one eye usually sorts the problem out for a few moments.
For some reason, high-street “opticians” do not like to prescribe and supply glasses where the double vision effect is lateral, they only like vertical prism lenses (prescription has a value - like +1.5 and the words “up” or “down” ). In a hospital, any Orthoptics technician can establish the direction and strength of any prism needed in about 10-15 minutes. If there is no value on your prescription for prism, then the optometrist must think that there is something else happening.

So, to answer your third question …

If you have a prescription, and are willing to take a chance, then, yes, you could get a pair of glasses to your new prescription. Do not order them over the Internet - go to another “optician”. There are several things involved with getting new glasses, such as how far apart your eyes are (normally between 63-67 mm), how wide the bridge of your nose is, how long the side-pieces need to be, and so on; and these are things that need a trained person in front of you to get them right.
One thing you can test for yourself - find somewhere that you can park up and look at a road-sign from about 50 yards. You want a square sign ideally. Now concentrate on each edge in turn, and see if you can detect a second edge displaced a bit from the real edge. If you can, then you probably need a prism lens, and prisms for single vision lenses are easy.
If you normally have bi-focals, I would be inclined to get a pair of single vision glasses just to drive in (who cares what they look like as long as they work well enough) and buy a pair of cheap reading glasses in your local supermarket. That should hold you until the appointment comes through.

There is, of course, more to getting your vision right than that, but that should get you off to a good start.


Hi, I have SPMS and at tthe moment I am suffering with optic neuritis because of the MS. My eye is painful and I have blurred vision and have lost some of my vision so would strongly suggest you do not drive until after you have seen the specialist. I have been told not to drive. As Shuffler has said your insurance could well be invalid if something should happen whilst driving. Hope you get your appt’ through quickly.



Hi I’m sp too but haven’t had ON for some years now like Janet say’s I wouldn’t consider driving whilst having eye problems you would never live with yourself if you had an accident and caused serious damage to either yourself or worse still someone else. Let someone else do the driving. I presume it’s opthamology you’ve been referred to, they are usually pretty quick once they get the doctors or opticians referall. Good luck & I hope you get sorted soon Sue x

Hi All

Thank you for some good advice. The Optometrist has categorically ruled out ON, she could tell this from the internal photos she took of my eyes.

Doctor Geoff thank you for your in depth answer - I am 35 and yes I am short sighteded in my left eye which is the same eye that has the astigmatism and is causing most of my sight problems at the moment. There was no mention of a prism on my prescription - so I think this may be a good sign? I have booked an apointment with Specsavers today to get measured for glasses - they do some lower priced frames with free lenses so at least I will know sooner rather than later if it just a sight problem or if there is anything more sinister going on. I will also do the self-vision test with the road sign - will probably get someone else to drive me though and then swap seats when parked up.

Fingers crossed that my vision will be rectified when I get my new specs.

Thank you all again Katsxx

Hi Kats.

I expect your ear infection is elevating your MS symptoms. That is usually what happens. Any infection and increase in temperature makes things worse. I have called my MS Nurse on many occasions since diagnosis in 2005 with elevated symptoms and the first question she always asks is do you have any infections at the moment.

I know that my Optic Neuritis is worse when driving as there are lots of messages going on at the same time. I cannot go on motorways now as I can’t cope with all the cars that I am focusing on whizzing by me. The increase in messages from the brain makes it very difficult. I don’t drive anywhere where I know it is going to be busy. Just nice quiet roads where I can drive at my own speed. To be honest though I don’t drive much at all now.

Take care when driving/

Shazzie xxx

DrGeoff - that’s the first I’ve heard of shortsightedness improving when you get older. I am very short sighted and have astigmatism too, so it would have been useful. I am just getting long sighted too. They are caused by two different things so the can’t cancel each other out, as I once hoped they would. That was when I was a kid and didn’t

Any significant change in prescription - which this is - should be looked into. Especially if you have MS.

Don’t mess with your vision!

While you wait for the more in-depths invistigations you could change your lenses, but accept that they may become wrong quickly. I wouldn’t drive either. I have driven with eye problems because I never gave it a thought and none of the doctors I saw mentioned it to me. That included being treated for iritis, which included putting eye drops in to dilate the pupil in one eye - now you do get told to stop driving!

I have had lots of double vision, and still can’t work out why I carried on driving! The otician who diagnosed my double vision said she could supply lenses - my double was diagonal. So I can’t see why they can’t do vertical and horizontal. The only thing I have on my prescription that has a + or - is nothting to do with a prism as I don’t have one in my glasses. I don’t know how prisms are described on a prescription, though


There are several reasons for short sight. The most common one is that the muscles that focus the eye are over-doing things and making the point of focus come in front of the retina. As one gets older these muscles relax and the focus gets nearer to the retina. Astigmatism is when these muscles stop acting in a co-ordinated manner, and pull the eyeball out-of-round. Long sight is when the eye is focussing beyond the retina.

If you have both long and short sight, it is most likely that one eye has each problem. However, you can get temporary short sight from inflammation caused by elevated blood glucose levels. Double vision on a diagonal can be dealt with very easily with a prism lens – all it takes is for a lens to be specially ground to the right prescription. This can be hard to get in a bi-focal. Normally, the chain “opticians” don’t like doing this, because they order the complete assembly from a central depot who do not want to do custom lenses. Single vision lenses are very easy, if there is no astigmatism, because the lens(es) in a pair of glasses is(are) cut from a larger circular blank and can just be rotated. Astigmatism requires that the lens is specially ground for both conditions.

On your prescription, “prism” is the fourth column for each eye the first three are Sph, Cyl, Axis, and the fifth column is Base (which is for up or down referring to the position of the base of the prism. The value in the prism column referres to the degree to which the prism deflect a ray of light. As you can see, the standard prescription does not allow for a diagonal prism. Double vision (diplopia) is caused by a different set of muscles to long or short sight, or by the nerves that feed impulses to those muscles.


Kats, in answer to your questions: 1) No, it’s not normal, but it’s not unheard of. Driving makes our visual system work pretty hard and can show up problems that we wouldn’t otherwise notice. 2) I don’t know, but given your experience when driving, it is very sensible to get your eyes properly checked out. High street opticians are very limited in what they can check and, as far as muscle problems and prisms go, in my experience, most don’t even check for it. Also, the retinal photos that opticians do only scratch the surface - someone with an apparently perfect retina could in fact have significant problems with their vision. 3) No, I don’t think so. I suspect that your relapse has affected your vision and perhaps also your hearing. It is very suspicious that this has all happened around the same time. Saying that, if your hearing IS a virus, then it may be that you are not relapsing at all - it could be a pseudo-relapse brought on by the virus. Given that you don’t know what’s going on, I would agree with the optician - wait to buy new glasses; your prescription may change again. Karen x

This explanation is what I’ve always been told.

I hope it’s OK to post a url to the NHS website.

I have been wearing glasses since junior school and my Mum is a Zoologist and Biology teacher so I believed what she told me. I have been told by many opticians that my eye balls are rugby ball shaped - which is why ‘hard’ contact lenses tend to fall out when I look to the side and blink.

Like the basic article says, I have always been told that my astigmatism is caused by a bumpy surface of my cornea.

I was told at the eye hospital that my double vision was being caused by my eye muscles not working ‘properly’ - which is why it came and went at the time. All part of my MS.

DoctorGeoff, I’ve always wondered where your username comes from. I assumed that you are a doctor (either MD or PhD) but I’m interested to know which. It’s nice to know how big the range of people and their skills and interests we have on this forum. Of course the biggest spread is the experiences we have of our MS.

Hi Ellen

You ask the nicest questions …
Yes, I am, with a PhD (speciality at that time was human vision and simulator displays).
I say “at that time” because simulators takes one toward training, training can take one toward the military, that can get you into all sorts of oddball things, so I have been involved with software development, lecturing in a raft of related things, and been to some interesting places.

I would think that your astigmatism is down to the odd shape of your eyeball, which is - like the hospital said - down to some of your eye muscles not working properly. Diplopia is usually caused by another set of eye muscles pulling part of the eyeball out of shape.

Some of the things that the experts say to the patients are not, to be kind, the full story. The attitude seems to be that the patient does not need to know (this is a remainder of the “Doctor knows best” attitude). I have had two GPs (same practice) who have said to me “I don’t know” which is one reason why I am inclined to trust what they do say.


A lot of what I have learned is through school/college/uni - my Mum taught Science and taught me that what we get taught isn’t exactly right! She says that she spent a lot of time telling the girls she taught that what she’d taught them before wasn’t quite right. Then repeating the same words a few years later :slight_smile:

We get a lot of things simplifed for us to make it either easy to understand or easy to explain. Teaching five year olds about sub-atomic physics may never work, for example. What I love about science, and especially Biology as that’s what I studied, is that it’s all theory and open to debate and constant review. Biology is all about ‘when x is y then z is a. except when it’s not.’

I just want shiney, new and perfect eyes. And optic nerves which aren’t damaged to go with them :slight_smile: