Evaluation of Pseudoisochromatic Plates for Grading

• Published in: JAPANESE ORTHOPTIC JOURNAL Vol. 25; pp. 233 - 237
• Main Authors: Ishiguro, Susumu, Akiyama, Maki, Tanabe, Shoko, Hukami, Kaitiro
• Format: Journal Article
• Language: English
• Published: JAPANESE ASSOCIATION OF CERTIFIED ORTHOPTISTS 1997
• Subjects: congenital color vision defect; degree of color vision defect; pseudoisochromatic plates
• ISSN: 0387-5172; 1883-9215
• DOI: 10.4263/jorthoptic.25.233

In order to evaluate the validity of grading plated, the results of the TMC Plates and Ishihara-Okuma Plates of 886 subjects, and those of the Ishihara tests of 1, 000 subjects were reviewed. Color vision defects of all the subjects were diagnosed with a battery of color vision tests including anomaloscope. With the TMC Plates, 20.1% of dichromats scored moderate or mild degree and 33.4% of anomalous trichromats scored high degree. With the Ishihara-Okuma Plates, 53.8% of dichromats scored moderate or mild degree and 10.8% of anomalous trichromats scored high degree. In each subject, diagnoses of two plates were often different. With the Ishihara test, 85.9% of anomalous trichromats were judged to be dichromats. Thus, results of grading plates are rather inconsistent with real degrees of color vision defects. The reason of such inconsistency is well explained when the colors used in the plates are plotted on Fransworth's Uniform Chromaicity Scale Diagram.