I went today to an opthamologist and had a full dilated eye exam including a retina exam. Everything seems fine. The doctor did ask me if I have migraines when I mentioned the grainy vision expisodes. This may well be a migraine aura or some kind of aura from the occipital lobe. Perhaps I should seek a third opinion?
What you describe is not typical for a migraine visual aura. Migraine auras aer usually described as flashing lights sometimes colors, at times in a zig-zag or fortification type pattern, they are described as scintillating or shimmering. The headache usually comes on within an hour of the aura.
Some people do have aura without headache, more common as we get older. In this case the clinical history may be typical, but mnay times other disorder have to be excluded such as stroke/TIA/vascular/seizure.
Sometimes similar symptoms, eg flashing lights, floaters, visual field defects can be due to eye or retina problems - this may be the case with you, alhtough I cannot give you a formal opinion over the internet as this website is educational only. For this reason if you have not seen an ophthalmologist for a full eye and retinal exam you should do so.
Good luck
Hi I have suffered with migraines for 30 years and get them with and without the aura. My sister also gets them, but said that lately she just gets the aura and no headache afterwards. She is older than I and thinks that mayble as we age they change. I get what I call flares that shoot across my vision and don't get the headache. I think they have many different symptoms. Good luck to you.