I went to bed with no symptoms (at least that I can remember) but woke up the following morning with dimmer vision and a feeling of tiredness (which mostly wore off after a few days). The dimmer brightness levels are identical in both eyes.
There is no optic nerve pain, or any other noticable symptoms (including no stroke type symptoms) apart from a tenderness or (maybe) slight pressure at the top of the head which also wore off after a few days.
This happened a month ago; there has been no recovery in brightness levels since then.
I've been to see a doctor and I am currently waiting to see a neurologist, but in the mean time I am wondering if anyone here has any ideas.
The doctor ran some blood tests, but apart from a reduced blood platelet count (which already existed prior to this incident), no anomalies were detected. In case the standard blood tests vary by country, I am in the UK.
My optician has determined that there has been no change in things like visual acuity and a retinal photograph does not show any noticable issues in the retina or the head of the optic nerve.
This same thing happened a few years ago (from which my brightness levels never really recovered) and the doctors were unable to determine a cause, although things like MS were eliminated as been the cause of that incident.
Thanks for any ideas.
PS: Given I've already been though this once without finding out what caused it, I am also open to ideas about how to get in touch with or referred to specialists in the UK who are used to tracking down unusual vision symptoms.