HI upon waking up just before I open my eyes, for a split second there is blackness before my eyes , as if a curtain went dawn. It passes when I open my eyes. It happened 3 times in the last few weeks, some time actually I can feel a shock or a click in the whole body , when it happens. Head CT did not show a thing, nor did eye check up. I am waiting for head MRI , and am advised to see a neurologist.I should add that tinnitus started in my right ear at the same time. ear check ups were also O.K. I am very frighten not knowing, what it my be, and need an advise as to what may be the cause of it or where to go for further diagnosis. Appreciate your help