Sudden loss of peripheral vision-- please help!?

Seek help. Vision may be lost peripherally from disasters within the eye such as retinal detachment or vascular occlusion; or from strokes in the brain in the occipital lobe or the pituitary region; or from systemic vascular collapse, drug toxicity or poisoning. You need to immediately see an ophthalmologist for this as some of these are extremely urgent and can affect both eyes.