Tunnel vision
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- This article refers to the medical condition. For the novel see Tunnel Vision; for the film see Tunnel Vision (film).
In medical terms, tunnel vision is the loss of peripheral vision with retention of central vision, resulting in a constricted circular tunnel-like field of vision.[1]
Tunnel vision can be caused by:
- Alcohol consumption causes tunnel vision [1]. In addition, the vision becomes blurred or double since eye muscles lose their precision causing them to be unable to focus on the same object.
- Retinitis pigmentosa, a disease of the eye.
- Group B Rally driving (1985, 1986) [2]
- Sustained (1 second or more) high accelerations [2]. Typically, flying an airplane with a centripetal acceleration of up to or over 39 m/s2 (4gs) with the head towards the center of curvature, common in aerobatic or fighter pilots. In these cases tunnel vision and brownout may proceed to or g-force induced Loss Of Consciousness (g-LOC).
- Hallucinogenic drugs.
- Glaucoma, a disease of the eye.
- Extreme fear or distress, most often in the context of a panic attack.
- During an intense physical fight.
- Altitude sickness, hypoxia in passenger aircraft [3]
- Exposure to oxygen at a partial pressure above 1.5-2 atmospheres, producing central nervous system oxygen toxicity, notably while diving. [4] Other symptoms can include dizziness, nausea, blindness, fatigue, anxiety, confusion and lack of coordination.
- Other loss of blood to the brain.
- Prolonged exposure to air contaminated with heated hydraulic fluids and oils, as can sometimes happen in passenger aircraft [5].
- Pituitary stalk mass (i.e. tumor) compressing optic nerve fibers
- Severe cataracts, causing a removal of most of the field of vision
When combined with piloting an aircraft, driving, crossing roads or operating heavy machinery, the consequences have been known to be fatal[citation needed].
[edit] References
- ^ Effects of Alcohol on Vision
- ^ a b c d Cullen, John. Petrolheads: Too fast to stay. Sligo Weekender. Retrieved on 2006-11-17.