[Correction of presbyopia in users of video terminals by progressive half-spectacles]. / Correction de la presbytie des utilisateurs d'écrans de visualisation par demi-lunettes progressives.

Twenty one presbyopes of 48 years old and over (considered as emmetropes or light ametropes), and a young aphakik patient wearing contact lenses, working before visualization screens, were equipped with semi-framed Varilux 2. The correction of their Intermediary Vision was made precisely on the upper edged level of the frame; the correction of their Near Vision was made by an addition of strength reduced by half when compared to the usual graduation. This specific equipment was compared to the classical system of their choice, manufactured at the same time and offering the same strength in Near Vision. This comparative study resulted in the following conclusions which were in most cases: a "normalization" of the distance to the working screen, an improved distinctness of characters in the intermediate and near distances, a very definite improvement of the vertical scanning when alternating between the keyboard and the screen, and of the horizontal scanning when alternating between the keyboard, or the screen, and the documents, an obvious diminution of the time of tiredness, and less stiffness of the neck in its usual working position, the proposed progressive half spectacles remained essentially a working tool, but most participants of this study used them for spare time activities, large professional categories (musicians, painters, etc.), including ours, might benefit from them. The possible benefits obtained from their use by aviators will be published separately. These half-framed progressive spectacles seemed to be the best optical complement to propose to aphakic patients wearing contact lenses and to the pseudophakics.