Question: My eyes go out of focus with no warning. If I close either eye, everything appears in focus. It can last from a couple of minutes to four or five hours. Recently, my eyes also go out of focus for a short time when I turn my head. What might this be?
Dr. Hibberd's Answer:
Your symptoms can be caused by a number of conditions, and I recommend you seek the advice of a neuro-opthamologist promptly. Any visual loss, whether temporary or persistent, always needs immediate evaluation. In your case, your visual pathways are intact, but the images from each eye presented to your visual cortex appear to be divergent. Differing images can be seen with disorders that affect the muscles controlling movement of the eye.
Children with strabismus (crossed eyes or lazy eyes) accommodate the divergence of images by suppressing the signal from one eye or the other, thus losing binocular vision. If left untreated, they will develop a condition called amblyopia ex anopsia that will not be reversible even if the crossed eyes are corrected. This is why it is so important for children to have strabismus corrected very early.
A number of conditions may affect one of the three cranial nerves that control each eye’s muscle movements, and only one eye may have its visual signal affected. We can compensate for the diverging image presented to our brain by closing one eye or the other.
Conditions affecting blood supply can induce transient ischemia that may precede permanent vision loss. This can also be a symptom of ocular migraine, and disorders such as multiple sclerosis must also be considered. Consult your doctor without delay.