Color Vision in Blue Cone Monochromacy: Outcome Measures for a Clinical Trial

Area of Science:

• Ophthalmology
• Genetics
• Vision Science

Background:

• Blue cone monochromacy (BCM) is an X-linked retinopathy caused by mutations in the OPN1LW/OPN1MW gene cluster.
• BCM is characterized by reduced visual acuity and impaired color vision.

Purpose of the Study:

• To evaluate color vision outcome measures for future clinical trials in Blue cone monochromacy.
• To assess the clinical feasibility and interpretability of arrangement tests and the Color Assessment and Diagnosis (CAD) test in BCM patients.

Main Methods:

• Retrospective case series of 36 BCM patients (ages 6-70) using the Farnsworth-Munsell (FM) D-15 test.
• A subset of six patients also underwent Roth-28 Hue and CAD testing.
• Comparison with normal-vision participants.

Main Results:

• All BCM patients exhibited abnormal results on D-15, Roth-28, and CAD tests.
• Protan-deutan confusion was observed with the D-15 test, without a bimodal tendency.
• Unexpected yellow-blue sensitivity abnormalities were noted, with varying severity based on age.

Conclusions:

• Arrangement tests and the CAD test are clinically feasible and interpretable for monitoring color vision in Blue cone monochromacy.
• These tests can serve as valuable outcome measures in clinical trials for BCM.