The HRR pseudoisochromatic plate (pip) test was originally designed as a screening and diagnostic test for color vision deficiencies. The original HRR test is now long out of print. We evaluate here the new 4th edition of the HRR test, produced in 2002 by Richmond Products. The 2002 edition was compared to the original 1955 edition for a group of subjects with normal color vision and a group wh...

Carriers of X-linked color vision deficiencies have previously been reported to exhibit mild abnormalities of color matching and discrimination. In a sample of 55 carriers of protan and deutan deficiencies and 55 age-matched normal controls, we measured chromatic discrimination along a red-green axis. We found that discrimination was impaired in the case of carriers of deutan deficiencies (whic...

PURPOSE The genetics underlying inherited color vision deficiencies is well understood: causative mutations change the copy number or sequence of the long (L), middle (M), or short (S) wavelength sensitive cone opsin genes. This study evaluated the potential of opsin gene analyses for use in clinical diagnosis of color vision defects. METHODS We tested 1872 human subjects using direct sequenc...

The groundwork for understanding color defects in eye disease was established by the end of the nineteenth century. Thereafter the field was neglected as scientists concentrated on studies of normal color vision and congenital color vision defects. Spurred by the development of the Farnsworth 100 hue-test, interest was renewed in the 1950s. The past 25 years have seen an explosion of interest i...

In the past, equine color vision was tested with stimuli composed either of painted cards or photographic slides or through physiological testing using electroretinogram flicker photometry. Some studies produced similar results, but others did not, demonstrating that there was not yet a definitive answer regarding color vision in horses (Equus caballus). In this study, a pseudoisochromatic plat...

This article presents a critical review of the literature surrounding the potential impact of undiagnosed and untreated vision impairment on reading development in the early years of primary school. Despite pre-school screening programmes, it is still possible for children to enter school with undiagnosed, uncorrected vision impairments. This can be due to healthcare access issues for children....

Aim: A commonly used method to examine the ability of the visual system to discriminate colours is based on isochromatic plates, such as the Ishihara plates. This article will introduce a computer-based method to determine red–green colour deficiencies based on presenting Ishihara plates using a CRT monitor. Method: The spectral emission of the reflected daylight of the plates was compared with...