title: A case of incomplete achromatopsia of the deutan type.
abstract: A 45 year old man was studied who was previously diagnosed as a typical achromat. Increment spectral sensitivity measurements on white and several colored backgrounds showed that he possessed a rod system, a cone system sensitive in the short wavelength region (blue cones) and a cone system sensitive in the long wavelength region (red cones). This investigation shows that rather extensive testing is required to classify incomplete achromats.
mesh_terms: D003119:Color Perception Tests / Q000295:instrumentation / Q000379:methods*; D003117:Color Vision Defects / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010786:Photoreceptor Cells / Q000503:physiopathology*