
ColorDx® CCT HD®
Key Features

Easy Testing - 4 Button Response Pad
• Facilitates maintaining fixation near the test area
• Reduces uncontrolled contrast adaptation and response time variability due to visual searching for the response character
• No inadvertent testing of keyboard / mouse skills, or hunting for one of 10 letters when the focus should be on taking the test

High Granularity

Patient color vision trends analysis
This feature enables you to clearly, graphically, and numerically see changes in cone-isolated results (both threshold and Standard Error) over time. A new standard for clinical research, clinical trials, and routine patient monitoring of acquired color deficiencies

CE mark and FDA listed

Robust Psi-marginal Adaptive Threshold and Error Estimation
• Published technique that has wide academic use
• Estimates contrast threshold and slope virtually free of bias
• Calculation of ”guess rate” from the posterior distribution
• Addresses nuisance parameters in an adaptive manner
• Background calculation of next ‘look-ahead” of calculated trials based on distribution of prior answers
• Shown to give higher precision in the threshold estimate when the threshold is designated to be the only parameter of primary interest and the slope and the lapse rate are treated as nuisance parameters

The Low Contrast Ceiling is Lifted
• Subjects were ”binned” into 5 basic threshold levels, the lowest of which contained the majority of responses
• There is significantly more performance data uncovered by testing to < 0.3 % contrast with highly granular contrast steps down to ~ 0.25%.

Photopic Cone Isolation
• Common ophthalmic tests specifying photopic conditions are variously conducted generally in the range of ~ 85 cd/m²
• CCT HD provides background luminance in the mid photopic range

Co-developed with USAF

OBVA allied partners testing cone-isolation contrast sensitivity
• Singapore, Australia, Canada, Israel, NAMI, USAARL, University of Melbourne, University of Waterloo, York University
• Effect of hypoxia on color vision – Japan

Adaptive fast testing or Full Threshold
If at the end of the adaptive sequence, the score is below the Pass/Fail criteria, the test seamlessly continues through full threshold testing, only for the individual cone population(s) less than Pass/Fail. Full Threshold is designed to minimize the “Standard Error” of the determined threshold.

Response Time as Secondary Performance Measure
As examples, individuals with poor sensitivity for a cone population would be expected to struggle and take more time to try to accurately identify the stimulus direction. Poor cone-isolation contrast sensitivity would be expected to have long response times. The contrary, poor scoring on cone-isolation contrast sensitivity accompanied with very fast test times may indicate purposeful random responses and / or disinterest in proper test administration.

Smart, Deep Synchronous Calibration
• Reliable cone contrasts tested at less than 0.2% are required to eliminate the contrast ceiling of the original CCT and challenge the true thresholds of human vision
• Periodic in-office calibration are alerted to the user once per month and the last calibration or verification date is printed on the exam report. Importantly, CCT HD does not fully stop use of the system until recalibration is completed (triggered by the lapse of a single calendar day). The calibration process only takes minutes.

Secure 256-bit encrypted patient data
• CCT HD uses 256 bit encryption with admin and user-specific user names and passwords.
• CCT HD also features permission-based remote training and service as well as one-button software updates.
Solid – Secure – Robust from Konan Medical

Language and literacy neutral, no character bias, Landolt C
A secondary measure, response timing, is also recorded and averaged for set of cone trials, with the guideline that slow response are expected to accompany difficulty in seeing the targets, and fast, confident responses are expected with normal color vision.
Easy to administer. Easy to take.

Low Sensitivity to Viewing Angle

Clear Auditory Feedback

Robust, beautiful reporting
Reports include on-screen help and tool tips are provided with routing features to select EMR systems. Print / PDF reports may be customized with clinic name and logo.

Monocular and Binocular Test Strategies & Scoring
CCT HD provides separate score criteria for binocular Vs. monocular testing. Most color vision testing should be performed monocularly.

Illustrated Help

Fully automated incremental backup

Service-Defined Pass / Fail Criteria
