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Safety Lenses

Studies show that there is unacceptably large number of eye injuries
occurring in the world. The visual impairment as a result of an eye injury
may vary from a slight reduction in visual acuity to the total blindness. In
the past these eye injuries have been associated with industrial occupations
only but now there are increasing number of eye injuries seen in sports,
leisure activities and at home also. All such ocular hazards caused by eye
injuries can be divided into two groups:
• Mechanical, and
• Non-mechanical.
Mechanical injuries may arise from a variety of causes and their effects
are generally divided into two main categories – contusion and perforation.
Contusion injury may result from various causes including flying blunt
objects, falling objects, explosions or compressed air accidents, fluids under
pressure escaping from burst pipes and water jets from fire hoses. The effects
of contusion on the various ocular structures are numerous. It may lead to
black eye, sub conjunctival hemorrhage, corneal abrasion, blow out fracture,
hyphaema, iridodialysis, cataract, choroidal ruptures, scleral ruptures, angle
recession, retinal hemorrhage etc., perforating ocular injuries can be caused
by foreign bodies.
Non-mechanical ocular injuries fall into four main categories – Chemical,
thermal, electrical and radiation. Most chemicals harm the eyes by direct
contact with the external ocular tissues. Concentrated Sulphuric acid from
exploding car batteries, household bleaches, detergents, disinfectants and
lime are examples of chemicals that can cause burns to the eyes. Thermal
injuries can be caused by flames and contact burns. Hot bodies, fluids or
gases are the usual sources. Burns usually involve the eyelids and not the
globe, which is often protected by reflex blink. Electrical injuries are basically
due to lighting and high tension electrical appliances. Injuries to eyebrows,
eyelashes with superficial burns of lids which are usually associated with
marked swelling and conjunctival chemosis are hazards caused by electrical