NEW symptoms during a pseudo exacerbation? Or what does optic neuritis look like?

[trevvian]

I was working outside today in 80 degree weather, when I realized the vision in my left eye was blurry like someone smeared vaseline in my eye. (My left leg also went limp and the pins and needles came back.)

After an hour in the AC, all symptoms, including the vision, completely resolved. Went back outside, and same thing again.

Seems like a classic heat-induced pseudo exacerbation. Except I've never had vision problems, never optic neuritis. So I don't even know if that's the type of vision problem that could be caused by MS.

Is it normal to find NEW symptoms caused by heat? Since it didn't last, doesn't seem neuro-worthy. But I'm curious about it & whether it's my MS being weird, or just a random anomoly.

[SNOOPY]

Hi trevvian.

I have never had it confirmed by a Neurologist but, I do believe a Pseudo-Exacerbation can cause a new symptom. I have had this happen to me a couple of times with the same outcome as you (cool down, new symptom goes away). When our core body temperature increases anything is possible. Heat makes our CNS go haywire.

Please be careful of the heat.

[KoKo]

Hi trevvian ~

Is it normal to find NEW symptoms caused by heat? Since it didn't last, doesn't seem neuro-worthy. But I'm curious about it & whether it's my MS being weird, or just a random anomoly.

It is my understanding that increased temperature can reveal existing nerve damage due to the slowing down of impaired nerve impulses.

The nerve damage may be "silent" under ideal conditions, but the heat can accentuate and bring out the existence of demyelination and impaired nerve signals.

For example, under normal, ideal conditons, I don't present with nystagmus (involuntary eye movements), but when I have a fever or my body gets too warm, it shows up. The damage is already there, but evidently not enough to be present at all times (thankfully, so far).

Take Care

[KoKo]

Uhthoff's Syndrome

Better explanation:

Uhthoff’s syndrome is described by patients as a dimming or reduction in vision, usually associated with exercise or overheating. It indicates partial myelin damage along the optic nerve as the visual signal goes from the eye to the brain. As a person’s temperature rises, even by less than one degree, the ability to conduct nerve impulses along damaged nerves is reduced. This visual problem improves with rest.

https://mymsaa.org/ms-information/sy...offs-syndrome/

Take Care

[trevvian]

Thanks...it sounds like a normal part of a disease that's anything but normal.

Guess I'll just chalk it up to the heat for now, and ask the neuro if there's anything apparent on my optic nerve next time I see him.

Vision problems are something I hoped to avoid.

[KoKo]

Hot Bath Test

Also interesting:

For many years, the “hot bath” test was used to diagnose multiple sclerosis. A person suspected of having MS was immersed in a hot tub of water, and the appearance of or worsening neurologic symptoms was taken as evidence the person had MS.

Many people with MS experience a temporary worsening of their symptoms when the weather is very hot or humid, or when they run a fever. These temporary changes can result from even a slight elevation in core body temperature (one-quarter to one-half of a degree). An elevated temperature further impairs the ability of a demyelinated nerve to conduct electrical impulses.

Activities including sunbathing, exercise, and taking very hot showers or baths can have the same effect. For example, some people notice their vision becomes blurred when they get overheated — a phenomenon known as Uhthoff's sign.

https://www.nationalmssociety.org/Li...re-Sensitivity

[trevvian]

@Koko, that's interesting. I'm very familiar with old symptoms getting worse when I overheat, but had never experienced blurred vision before, so that one took me by surprise. I suppose it's possible I have deymyelination that just hasn't actually caused symptoms previously.

[KoKo]

I'm very familiar with old symptoms getting worse when I overheat, but had never experienced blurred vision before, so that one took me by surprise.

trevvian ~

I see what you're saying, that blurred vision is a brand new symptom for you, which took you by surprise when it showed up.

That would be somewhat disconcerting, especially with your having RRMS, and being on a DMT.

From what I understand, optic neuritis (if that's what is happening) often resolves over time.

Hope that happens for you.

Take Care