Clinical Application of Two-Color Dark Adaptometry: A Case Series

Title Clinical Application of Two-Color Dark Adaptometry: A Case Series
Author, Co-Author Carolyn Talbert, Ruh Patel, Brooke Houser, Jeff Rabin
Topic Functional Vision/Pediatrics
Program Number
Ballroom A-B
UIW Rosenberg School of Optometry

Background:  Numerous retinal diseases include sensitivity loss under dark and/or light adapted conditions. However, dark adaptometry (DA), which quantifies dark and light adaptation, is an elusive test available only at medical centers and universities which include related testing: flash, multi-focal, pattern electroretinography (ERGs), electro-oculography (EOGs), visual evoked potentials (VEPs) conducted in accord with international standards (www.iscev.ogr). To improve diagnosis of ocular disease, we developed a DA test to be given during the 20 minute dark adaptation phase of flash ERGs. The test is conducted in the Ganzfeld used for ERGs (Diagnosys, LLC) with alternating red and blue stimuli to elicit responses from cones (red) and rods (blue) yielding a red and blue two-curve DA function during. The final DA thresholds, sensitivity during various points during the 20 minute DA period, and amount of time to achieve specific levels of sensitivity were used to for diagnosis. We describe the efficacy of this technique for diagnosis in a diverse series of patients referred to our Visual Neurophysiology Service from Ophthalmology Retinal Specialists. 

Case Series: The efficacy of two color red-blue DA will be described in three case in conjunction with multiple additional tests including full field flash ERGs, mfERGs, EOGs, and advanced color vision testing. Cases include Ushers syndrome (hereditary hearing loss and retinitis pigmentosa; RP), fundus albipunctatus (rare disorder affecting night vision), and an atypical late onset variant of tapeto-retinal degeneration (variant of RP). 

Conclusions: Insofar as most patients requiring ERGs for definitive diagnosis also benefit from DA testing, the new two-color red-blue DA test, conducted during the dark adaptation phase of ISCEV flash ERGs, offer invaluable adjunctive information to substantiate diagnosis and offer a basis for tracking visual function over time.

Affiliation of Co-Authors UIW Rosenberg School of Optometry, UIW Rosenberg School of Optometry, UIW Rosenberg School of Optometry