Medical legal validity of the use of the anomaloscope in the dyschromatopsia of aspiring civil and military aircraft pilots

Abstract

Color blindness is a condition of altered color perception, scientifically defined as "dyschromatopsia". Color blindness affects 8% of the world population. Color blindness is caused by an alteration of the cones that influences the vision of the color self (red, green, blue). A comparative study was conducted in dischromatopsic subjects identified during the course of the ordinary investigations directed towards the civil aero-navigating personnel by the Ophthalmology Department of the Air Force, between March 2019 and January 2020, at "Aldo Di Loreto" Institute of Aeronautical and Space Medicine of Rome. 10 subjects aged 20 to 50, with dyschromatopsia found at Ishihara's pseudoisochromatic tables, were submitted to Oculus HMC-Anomaloscope with a manual execution program and then a CAD test. Thus, in 2 out of 10 cases of dyschromatopsia, the Anomaloscope would have guided the medical judgement, while the CAD test would have oriented towards a judgment of full fitness despite the same lack of chromatic sensitivity however, underlined by both tests. In conclusion, the CAD test confirmed a highly sensitive and specific method of determining the presence and depth of the chromatic perception deficit but also the method was able to prevent the unjust refusal of certain air navigation activities to the aspirant staff.