Visibility Vol 16 Issue 4, 2022


Mesopic Full-field Stimulus Threshold Testing – a Quick Method to Determine that Low Light Dysfunction is due to Poor Rod and Cone Function


The main objective of this preliminary study was to test a protocol of mesopic full-field stimulus threshold (mFST) testing to assess rod and cone function in controls and individuals poor low light functioning (due to retinitis pigmentosa; RP). Typically dark adapted black background FST testing requires pupil dilation and dark adaptation for at least 30 to 45 minutes. This traditional process of FST testing requires 45 to 60 minutes to complete the testing. We hypothesized that rod and cone function assessment can be achieved by performing FST in mesopic (low light; 0.01 cd/m2 to 3.0 cd/m2) back ground luminance without either pupil dilation or dark adaptation which then only requires 5 minutes of testing. Most nighttime outdoor and street lighting conditions are in the mesopic range of lighting.

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Callie Victor, PhD, OTR/L, CLA; Matthew Haase, MS, OTR/L, ATC; Michael Bown; Lindsey Bates, OTR; Michael Centra, OTR/L; Jaclyn Sachleben; Elizabeth Tyson; Michelle Gamber, DrPH; Suleiman Alibhai

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Characteristics of Older Bioptic Drivers: Effects of Increasing Age on Driving Safety

Bradley E. Dougherty, OD, PhD

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