Have occasional issue where my eyes feel like the are crossed or a loss of my depth perception. My eyes feel like they are crossed but my vision is not double and when I look in a mirror they are not. Also when I cover one eye at a time my vision is fine except no depth. During this time I am unable to keep my balance and my head feels like there is a vise grip on it. It usually last only 5 to 10 minutes with no lasting effects.