Radiation Injury to the Eye

Special attention should be drawn to changes of the organ of vision when exposed to different kinds of radiation energy (infra­red, ultra-violet, ultrasonic, X-ray, radio- and microwave, alfa-, beta-, gamma-rays, radiation of optic quant generators, etc).

Ultraviolet radiation causes the so-called electroophthalmia which is frequently observed after the influence of radiation in electric welding. Inflammation develops after the latent period which lasts for 4-10 hours. The symptoms are the following: photophobia, lac­rimation, hyperemia of the conjunctiva. The cornea is transparent, bright, though sometimes there are fine swellings of the epithelium.

The similar clinical picture is observed in snow blindness or snow ophthalmia. Which occurs in members of polar expedition and mountain tourists due to great reflection of ultra-violet rays get­ting to the earth through the pure air.

Treatment consists of instillation of 0.25-0.5% solution of dic-aine, 2% solution of novocaine, cod liver oil, sea buckthorn oil as well as 3% solution of sodium sulfacyl to prevent infection.

Infra-red radiation greatly affects the eye causing formation of complicated cataract. It is observed in workers of hot sections (founders, metallurgists, steel founders, glass-blowers). Pathogen­esis of this cataract depends on effect of short-waved portion of the infra-red rays on the lens, on the one hand, and of high tem­perature on the anterior section of the eyeball on the other hand.

Excessive infra-red radiation may result in retinal oedema and sometimes in haemorrhages into the vitreous and retina.

X-ray radiation may lead to complicated cataract as disc-live clouding in the posterior layer of the crystalline. Lens sensitivity to X-ray decreasing with aging and severity depends on rediation dose. Cataract develops after quite long latent period (from 2 to 17 years) and seldom reaches complete maturation.

Lenticular opacity is also characteristic of hard gamma-radia­tion, affection by neurons or excessive microwave radiation (fre­quent therapeutic diathermia, violation of the norms of work with

radars).

Ultrasound radiation on overdosage may result in corneal oede­ma with subsequent development of bulleous keratopathy, iris po­rosity with its possible partial atrophy.

At present light energy of optic quant generators is widely used in ophthalmology with therapeutic and surgical purpose. It is es­tablished that long work with laser leads to numerous punctate sub-capillary opacity in the lens. Not direct but reflected laser rays get into the eye. In exposure to direct rays of ruby laser there may be dystrophic changes of the retina.

Prophylaxis of the professional eye injuries consists, first of all, in strict observance of safety rules, norm of the uttermost permis­sible concentration of the toxic gases, evaporations and dust in the air of the work premises; use of eye protective devices (protective eye glasses, hand-shields made of stained glass, protective glass and walls containing up to 30% of lead, etc).

Date: 2015-02-03; view: 848