Sorry, I know a few that get migraine headaches at times, including my wife of 24 years and middle child who’s now 20 years old.
Now I don’t migraine headaches per se, but I do get “ocular migraines” which sounds similar to your description.
My symptoms varies;
-sparklies like you describe
-intense flashes
Or
-the worst is when my vision collapses into a tunnel and I have to literally stop whatever I’m doing and let it pass. Yes, it’s happened while I was driving on highway and I pulled over with hazards blinking on as vision was quickly going, very scary, I was so shook up from that.
Thru all the eye doctor testing my eye nerve is good, the inside “guts”, etc.
Me; I’m near 62 and these ocular migraines started … 7-8 years ago.
They come and go in random ways, nothing I can equate as cause and effect.
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