Intermittent Vision distortions

[plent2d]

I am a 52 yo male with no health problems (i'm aware of) other then this..I am a smoker, a vegetarian and excercise pretty regularly..mainly by running.
Feb 2 yrs ago i was driving around NZ on holiday when i noticed i could not see the right half of the car number plate in front of me..this went on for about 30 mins then passed.
A month later i was at work when i realised i could not see what i was trying to read at work..again around 30 mins duration.
A week later i came home after a run and realised i could not see the right 1/2 of what i was trying to read on my pc..again it lasted about 30 mins.
Next day it happened again.
At this point i was freaking out so managed to arrange an appointment at my GPs (even though i couldn't read the phone book lol)
She said she'd covered this in her training and happily informed my about tumours etc..Anyway i had blood tests but nothing turned up except a possible minor infection which showed from a slight increase in my white cell count..
I had no more symptoms until almost exactly 2 yrs later..last month.
I was coming home in broad daylight from a course at work and feeling very relaxed when i realised i couldn't see what i was focussing on..people, cars signs..it was as though they didn't exist but everything around them did...again 30 mins or so duration.
Then 2 weeks later after another run..it happened again.
Only this time on the left side?
I'll attempt to describe what it's like...it's as though there's a curved downwards silver rippling ribbon in the same place in both of my eyes with a blank area below it where i can't see. Not a hole but an absence...?
I have no pain nor any other obvious symptoms whilst this occurs...
My fasting Cholesterol was slightly high but i take Vit C 1G daily to sort that.
Flummoxed???
ps
Family history from my sister re her 'hemianoepia' experience.

"CT scan "normal for my age", Carotid Doppler's showed 50% blockage - again apparently normal for my age. MRI scan also normal. Serum cholesterol through the roof and am now on anticholesterol meds and levels well down. I know you have views on this med but seems to have done its job and would rather have low readings than high, with their association with strokes.

Have had a couple of similar episodes since the. Happened when I was tired and dehydrated, I think. Also occurred on either side and passed off in ten minutes or so."

[Freddd]

Hi Plent2d,

Come on over the the b12 is hard to diagnose. That could be your problem, or part of it.

[chrismia]

You are having what are known as visual migrains.
They are very scary but are not dangerous.
The best thing you can do is lie down until they pass. They are not indicative of anything really serious going on.
Of course it is always advisable to get a second opinion after an internet diagnosis.
Best wishes for good health,