I may have posted this earlier but I have been SS free since Sept.
Last June my doctor recomended I have my vision checked. I was very
skeptical but was overdue for a new prescription anyway. I purchased
some very expensive transition lenses to handle both astigmatism and
myopia. The result is that I wear glasses much more often now. The SS
attacks disappeared almost as soon as I started wearing them.
I had maybe three since then and prior to that I was getting two or
three really bad ones a week.
I theorize that my visual cortex was overstimulated by the astigmatic
imagery coming in from the retina and this resulted in the strong
frequent CSD attacks.