A medical condition that results in a loss of peripheral vision is known as Tunnel vision. With tunnel vision a person can only see objects from within a circular field.
Tunnel vision can be caused by:
Extreme fear or distress, most often in the context of a panic attack.
Blood loss to the brain, for example, can lead to tunnel vision
A tumour pressing against the optic never fibres.
Some eye diseases may also lead to tunnel vision such as Retinitis Pigmentosa, an inherited condition that may ultimately lead to blindness.
Glaucoma, a disease affecting the optic nerve, can also cause tunnel vision.
