|
10% of all trauma in sport involves the eyes, yet they represent just 0.27% of the body surface. Many people think that ocular injury will not happen to them, amateurs because they don't hit the ball sufficiently hard, and professionals because they feel they can avoid injury through increased skill. Both of these assumptions are incorrect. Everybody playing sports is potentially at risk of eye injury, be it direct trauma or the more insidious damage caused by UV radiation.
High risk sports for trauma include combat sports, cricket, football, rugby, hockey and racquet sports. Injuries can be caused by the projectile (ball, shuttlecock etc.) or by opponents’ elbows and fingers.
There are more eye injuries from football than any other single sport but there are more injuries from the combined racket sports of badminton, tennis and squash. In fact, 35% of sports eye injuries are from racket sports.
In squash the speed of the ball is somewhere between 130 and 145mph and the ball is small enough to fit in the eyeball socket and damage the eye more. Players can also be hit by their opponents’ rackets. Speeds of well over 120 miles an hour though are common. Squash is the only sport which recommends eye protection for all players following the publication of a British Standards document (BS 7930-1). It is now mandatory to wear eye approved eye protection for all squash players under the age of 18 and any doubles events.
In badminton, the shuttle-cock reaches speeds of 145 mph whereas in table tennis the 40 mm ball may travel at only 100 mph but being closer to your opponent you have only 6/100th of a second to react or it may have such spin that it can rotate more than 100 times per second. However, very few players are seriously injured by a table tennis ball.
The important factors determining the extent of injury is the kinetic energy of the projectile, the point of impact, the shape of the ocular structures and the shape of the projectile. The nature of the injury depends on the exact situation but generally they are high energy blunt impacts which can lead to:
- Black eyes
- Conjunctival haemorrhage
- Orbital blow-out fractures
- Iris damage
- Secondary glaucoma
- Rupture of the globe
- Corneal abrasions
- Hyphaema
- Cataract
- Vitreous haemorrhage
- Retinal detachment or tear
- Retinal swelling
Virtually all of these are potentially blinding conditions.
The good news is that the majority can be avoided with simple preventative measures. Sports eyewear is designed to resist impact from fast moving objects such as squash balls or pebbles when cycling. They can also include a contrast enhancement filter to increase the quality of vision. These protective appliances have, in the past, received a bad press but modern equipment is much more fashionable and comfortable. All products conform to the relevant British or European Standard and many can be found in our online catalogue.
Much of what has been discussed above is even more critical for those who only have good vision through one eye. This needs extra care because injury would be catastrophic.
The right tint?
All sports played outdoors increase the risk of damage caused by UV radiation, especially with recent changes to the thickness of the ozone layer in the atmosphere. In the short term, exposure to excessive levels of UV can cause discomfort, watering and photophobia e.g. snow blindness. This resolves in a couple of days and causes very little lasting damage. However, long term exposure can lead to chronic ocular changes such as cataract, macular degeneration, pterygium, pinguecula and basal cell carcinoma. UV exposure is a particular problem with water sports and winter outdoor activities.
All lenses used outdoors should provide protection from UVA and UVB no matter how dark the tint. Lenses can be coated to block out UV rays and polarising lenses cut down reflections off snow and water. It is also important to block out the blue end of the visible spectrum that can also lead to the symptoms described above. These tints are often a red/orange colour and can increase contrast and clear haze. However, lenses should not be too dark as they unnecessarily enlarge the pupil, reduce depth of field and hence the quality of vision.
To decide on the best tint you should consider the brightness of the ambient light, the colour of the target and background and its contrast.
Neutral grey filters keep colours looking natural. This is important in golf, mountaineering and skiing.
Polarising filters are good for reducing reflected glare. This is important for fishing, water sports and cycling on wet roads.
Anti-reflection coatings remove the distracting reflections from lens surfaces. This is recommended for racket sports, fishing, shooting and archery.
It is important to incorporate a suitable filter in ski visors and goggles to protect against the strong reflectivity of snow at high altitudes.
Sometimes it is necessary to use sports appliances to give clear vision when it is inappropriate to wear glasses or contact lenses. This includes swimming, diving and other water based sports. It is possible to get a range of products incorporating a prescription to give clear vision without additional glasses.
|
