Cataract is derived from Greek and Latin word which means ‘to fall down’ or ‘waterfall’. The human eye lens is naturally crystalline. Cataract is any opacity to this natural crystalline lens. It causes visual loss and blindness in humans, other mammals and birds. Generally, visual loss from cataract other than from trauma is gradual and painless.
The etiology of cataract can be any injury or trauma to the lens, including contusion injury, inflammation within the eye or uveitis, metabolic conditions like diabetes mellitus, intraocular diseases like retinal detachment, and intraocular tumors like melanoma, retinoblastoma or congenital factors.
The common signs and symptoms of cataract are glare or intolerance of bright light, uniocular polyopia, which is doubling or trebling of objects, colored halos, perception of black spots in front of eyes, blurring, distortion and misty appearance of images and ultimately vision loss. Diagnostic methods include testing for visual acuity, presence of iris shadow in the test for iris shadow, checking for the color of lens through oblique illumination, black shadow against red glow or absence of red glow in the distant direct ophthalmoscopic examination and checking for opacity site, shape, size, color and pattern through slit lamp examination.
Cataract can be treated through surgical procedure. Surgical removal of the cataractous lens is and the replacement of the optical power of the lens is the only effective method to restore lost vision. Intracapsular cataract extraction and extracapsular cataract extraction with intraocular lens implantation are the most common surgical procedures to treat cataract.
Majority of the cataracts can’t be prevented, though, sometimes, visual disability and blindness can be prevented in some cases. Secondary traumatic cataract in children can be prevented by education and eye safety. Safety measure like protective measures and use of goggles to prevent trauma to lens are recommended for people working in unsafe conditions. Early detection and treatment of uveitis, prompt treatment of penetrating eye injuries, proper control of diabetes and constant monitoring of patients taking medications like corticosteroids can help to effective measures to prevent its occurrence.
Reference
Schwab, Larry. Eye Care in Developing Nations (7th ed.). UK: Manson, 2007.Print.
