Concern over VDUs is overplayed

A couple of additional points to the advice given by David Thomson on VDU users (optician, May 15 and 22). At the VDU workstation, there is normally no significant difference between the subject's near visual working distances. Paperwork is displaced away from the eyes by the keyboard, becoming as far away as the screen. Only exceptionally is there any optical basis for dispensing screen/near multifocals. Varifocals may not be easy to use when paperwork is well to the side of the screen. Single-vision intermediate is the most applicable lens form. There is nothing special about VDUs. Aside from simple, optical issues of object position, there is insufficient scientific basis for our particular interest in screens. Cathode ray tubes flicker and, although this is usually subliminal, it does make reading a little harder than with paperwork, but there is nothing we can do about it. The eyes may dry a little but this is rarely of consequence. Yet student optometrists are trained to ask patients whether they use VDUs alongside questions about personal and family ocular and general disease. Perhaps we should now stop emphasising VDU use. This issue is echoed by, for example, the promotion of lenses to block the little solar UV to which the British are exposed. We are in a responsible position and surely need good, demonstrable reason to create or exploit anxiety. David Burns London N8