A few. Cortical blindness is due to failure of the occipital lobe, the visual information processing center of the brain, to function properly. Many of these occur at birth. The eyes frequently are normal with normal pupillary reaction, yet the patient reports not seeing anything. There are tests of cortical electrical activity (vep) similar to an eeg which can register the lack of activity.
Brain vision loss. The eye sends information to the brain (occipital lobe) which computes the image we see as vision. If there is a disturbance to the function of this part of the brain, that is short term and returns to normal, we call it transient cortical blindness. This can be a circulatory problem, due to trauma or to some rare drug side effects. A neurologist can help you sort this out.
Inability to see. Cortical blindness is loss of acuity due to damage to the occipital lobe of the brain. This can be a birth defect or an acquired vascular defect. If at birth, the child will show no recognition of the space around him, the eyes usually will dance (nystagmus) and will not track together. As an adult, the eyes cannot fixate, the pupils usually react to light but no vision will be reported.
Brain blindness. The occipital lobe and the optic connections to it allow for the making of images which we call vision. If these tissues are damaged by tumors or strokes, you can lose vision even though the eyes usually are normal. This is called cortical blindness. It sometimes occurs in newborns as a birth defect.
Multiple. The back part of your brain, the occipital lobe is what 'sees' images, your eyes are just fancy attenaes transmitting the image to your occipital lobe. If there is anything wrong with the cortex of your occipital lobe, this is cortical blindness. Stroke, migraine, seizures, tumors, all can be problems.
No. That's when you're brain can't process the information, and eye is usually fine. There is no treatement for this at this time.
Usually reversible. Posterior reversible encephalopathy syndrome (pres) is a syndrome characterized by headache, confusion, seizures and visual loss. There have been reported cases presenting with cortical blindness with near or complete recovery of vision. There are many implicated causes, including ecclampsia, malignant hypertension, tacrolimus and Cyclosporine use, hypercalcemia. Treatment depends on the cause.
None known. This is usually the result of a cerebral infarction in the visual part of the brain. Once the pattern of loss is established, the loss is permanent and no known treatment exists.
Blindness after bonk. Transient cortical blindness - the name says it all. This is blindness which is temporary due to injury of the brain (not the eye) following trauma.