I have had two attacks of the following visual symptoms:

Whilst working on my computer there was a distortion right in the centre of my field of vision. A circular shape of blurred distortion, it was a swirl, rather like a vortex. I could not see the letters clearly within this distortion and the distortion made everything within its periphery blurred. The distortion was not limited to looking at the computer but remained in the centre of my vision for twenty minutes or so, but it is difficult to know exactly as I was rather stressed by this. It then become elongated and appeared to move to the upper left of my field of vision, although this was occurring in both eyes as closing each of my eyes in turn made no difference. The whole event lasted about an hour although again I cannot be precise. I had already a slight headache but after this I had a different kind of a headache which was not migraine.

Two days later there was another occurrence again whilst working on the computer. The event was more or less the same except his time for a few minutes towards the end of the attack I lost some vision on left side of my field of vision. A blind spot right in the corner. Again there followed another headache which was not migraine but which was somewhat worse in intensity than on the previous occasion.

Also the following my be relevant.

Since having migraine and chronic daily headaches I have from time to time experienced difficulties with reading, although I do not know if there is any connection to my headaches or migraine. This difficulty is the result of odd distortions somewhat similar to those described for visual dyslexia.

Whilst reading it appears as though the lines of writing are about to merge although they do not. Sometimes its appears as though the words are jittery as if they are about to jump about on the page but don’t, although it does not sound much it is sufficient to be disconcerting and makes it a strain to read. It is in a way rather similar to what happens with horizontal patterns and how they appear to move and the lines to merge.

Also it appears that at times, but not always, as though the vortex disturbance is about to begin again but does not quite happen. Also words seem to faded in patches, the colours are less bright. This really is difficult to explain. I have had this checked out with an optician at least ten years ago now, maybe more, and was given coloured sheets of plastic which helped make it easier to read. My present optician has made no comment when I tried to explain this problem to him when I had an appointment recently after the above attacks.

This problem comes and goes and varies in intensity, however since the two attacks described above this problem has become much worse and it is very difficult to read now it is as though the print is about to move , it appears to be jerky. Also recently I have experienced a slight soreness of my eyes after prolonged use of the computer

Since writing this in October my problems with reading particularly on a computer screen have become much worse. After a very short, while sometime only a few minutes the print is distorted as described above. In addition, after a short time, there appears an elongated diagonal oval inside which writing seems to fluctuate in a wave like motion, the greatest intensity in the middle of the oval gradually diminishing at the edges. The right eye sometimes appears to do this more than the left but it occurs in both eyes simultaneously. In the last week or so I am experiencing a quite significant increase in eye soreness within ten minutes or so of any activity on my computer.

Since my last appointment with the ophthalmic doctor I have had two further attacks of the visual anomaly with flashing lights described above. It seems that after the last episode my problem with reading is worse. However these two attacks where not as severe as the first two and no two attacks have been the same. After the most recent attack I had a headache different from the usual tension headaches and migraine with pain when I cough or bent down. Incidentally whist reading from a book the problem is not as severe as when reading from a computer screen but it can still be very difficult to focus to read but it is less so when using my grey plastic sheet.