الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Welding is defined by the American Welding Society (AWS) as a localized coalescence of metals or non metals produced either by heating the materials to the required welding temperatures, with or without the application of pressure, or by the application of pressure alone, and with or without the use of filler material.
Different types of welding are present in the market. These include gas welding, arc welding (SMAW, SAW, MIG, TIG and PAW), resistance welding and solid state welding. The 2 most common types present are gas welding and SMAW arc welding.
Welding arc emits a wide spectrum of radiations. Those in the visible and near infrared spectrum (400-1400) penetrate the eye to be absorbed by the retina and may cause thermal or photochemical damage depending on intensity, duration of exposure and the wavelength emitted.
Clinical manifestations of welder maculopathy usually develop 1-4 hours after exposure to welding arc and include unilateral or bilateral decreased vision, metamorphopsia and central scotomata. Visual acuity ranges from 20/40 to 20/200 acutely. A small yellow spot with a gray margin may be noted in the foveolar or parafoveolar area shortly after exposure which in mild cases may not be visible ophthalmoscopically. The yellow lesion is replaced by a permanent focal depression, with RPE mottling or a lamellar hole during the weeks following injury. Vision usually improves to 20/20 to 20/40 within 6 months, although scotomata and metamorphopsia can persist.
FA is an important tool in diagnosing welder maculopathy. Abnormalities found to be RPE window defect whether fovea or parafoveal. OCT is a relatively new tool for diagnosing macular diseases. Abnormalities included hyper reflectivity in the outer foveal retina or interruption of IS/OS junction corresponding to the junction between the photoreceptor inner and outer segments.
PPE is the most preventive measure for welder maculopathy. It may be welding shield alone which contains filter to prevent specific wavelengths from reaching the retina, goggles alone that assist in preventing welder maculopathy from occurring and to prevent striking objects from hitting the eye.
This prospective study was designed to clarify the effect of exposure to welding arcs on the retina of welders working in Alexandria and to compare the findings with a matched group of non welders in the same working places.
This study was carried out on 400 welders chosen from various industrial sectors, which are private, petroleum, and small workshops. Inclusion criteria were working between 40 hours/week for at least one year and age group between 18 -60 years. A matched group of 400 workers from the same places were taken as control group. The latter had no history of occupational exposure to welding but showed the same demographic characteristics, such as age, educati