[Value of very low voltage halogen lighting of desaturated panel D 15 test in established glaucoma]

The colour vision of a first group of glaucomatous patients was tested with the desaturated Panel D 15 test, first illuminated by a 300 lux Macbeth lamp, then with a very low voltage 1000 lux halogen lamp. In addition to the recording of 80% cases of dyschromatopsia, in line with previously published data, we demonstrated a great number (33.3%) of red-green axis anomalies under Macbeth light and, paradoxically, even more under halogen light (53.3%). To explain this high percentage of red-green axes under halogen light, we discuss the influence of luminance and emission spectrum of the light source. We conclude that the use of high luminance halogen light is capable of revealing concealed Verriest type II dyschromatopsias probably due to a specific fragilisation of the red-green channels induced by the glaucoma disease. This original colour vision testing procedure applied on established glaucomatous patients enabled us to easily obtain a factor of severity in the course of the disease.