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These findings suggest that accurate measurements of RG and YB colour thresholds can provide a sensitive measure of functional change in diseases of the retina with patterns of loss that differ significantly in AMD and diabetes.

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Purpose Age Related Macular Degeneration (ARMD) is the leading cause of blindness in the developed world in people over the age of 50. Its prevalence increases with age as does diabetes. Such conditions affect the metabolic stability of the retina, resulting in non‐inflammatory damage to retinal structures, and finally retinopathy. These changes to the visual pathway result in colour vision loss and in general, diminished visual performance. The aim of this study was to quantify accurately using sensitive visual tests the severity of visual loss in subjects with ARMD and diabetes. Methods We investigated a large number of ARMD and Diabetic subjects with varying degrees of retinopathy and assessed their colour vision, achromatic high contrast acuity and flicker sensitivity under photopic and mesopic viewing conditions. Results Results show a loss of chromatic sensitivity in both the red‐green and yellow‐blue channels, more pronounced under mesopic viewing condition. It was observed that chromatic loss was not localised to the site of retinopathy but affected peripheral retina also. Flicker sensitivity and contrast acuity loss were also observed in all subjects diagnosed with the above conditions. Preliminary findings show that significant loss of chromatic and flicker sensitivity precedes structural changes in the retina as revealed in conventional fundus imaging. Conclusion The results so far suggest that loss of chromatic sensitivity is the most sensitive measure for detection of early damage in subjects with eye disease and can be used to detect and to monitor the progress of disease or the outcome of treatment.

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Purpose Concern has been expressed that current colour vision (CV) standards in occupational environments tend to screen for normal trichromacy and may not therefore relate directly to actual CV requirements within specific working environments. Methods The new approach of establishing CV limits for specific occupations involves: ‐ measuring chromatic sensitivity and investigating the variability amongst normal trichromats ‐ accurate assessment of the severity of CV loss ‐ identifying the most important colour‐critical tasks at the work place when no redundancy is involved and discrimination of colour differences is most difficult ‐ simulating the most critical colour‐based tasks identified ‐ correlating the level of chromatic sensitivity and the subject’s performance of these tasks. Results A large number of normal trichromats and colour deficient observers have been examined on the CAD (Colour Assessment & Diagnosis) test. The test provides an accurate measure of the severity of CV loss (for red‐green and yellow‐blue discrimination) and diagnoses the class of deficiency involved. The findings from this study so far have produced minimum CV requirements in two specific occupational environments. These limits specify the level of chromatic sensitivity loss below which colour deficient subjects no longer perform the most demanding colour related tasks with the same accuracy as normal trichromats. Conclusion The new approach provides evidence‐based guidelines for minimum CV standards that can be implemented through objective testing without having to rely on either arbitrary limits or normal trichromacy. Further, this approach can be extended to other occupational environments where colour is important for carrying out visual tasks.

Purpose Diabetic retinopathy is a major cause of blindness in the Western World and remains one of the most serious complications of diabetes mellitus. The gold standard to measure functional change in diabetic (DB) patients is LogMAR or Snellen VA. The aim of this study was to measure and characterise the severity of visual function loss in subjects with DB using sensitive psychophysical tests and to quantify accurately how changes in management of the disease correlate with changes in visual function. Methods Three groups of patients (n=50) were included in this study:DB patients with and without retinopathy and patients with no DB. Each patient had a full ophthalmic examination prior to psychophysical assessment. Colour vision assessment was carried out using the CAD test (Colour Assessment & Diagnosis) that provides a measure of both yellow‐blue and red‐green loss of chromatic sensitivity (CS). Rapid flicker (RF) was also measured by assessing sensitivity to a 20Hz flicker stimulus at five locations in the central visual field (fovea and 1.5 degrees from fixation in each quadrant). All tests were carried out at photopic and high mesopic light. Results The results show significant loss of CS (p <.001) and some loss in RF sensitivity (p <.01). The most sensitive measure of visual loss was CS.There was also a positive correlation between CAD thresholds as a measure of CS and improved DB control. Conclusion The results suggest that loss of visual function precedes structural changes in the retina and could be used as a means of detecting early structural changes in the retina that precede clinical diagnosis of retinopathy. Preliminary results also suggest that changes in CAD thresholds provide an objective way of monitoring the progress of DB and/or treatment outcome.

Purpose Treatments for myopia progression are now available, but implementing these into clinical practice will place a burden on the eye care workforce. This study estimated the full‐time equivalent (FTE) workforce required to implement myopia control treatments in the UK and Ireland. Methods To estimate the number of 6‐ to 21‐year‐olds with myopia, two models utilising separate data sources were developed. The examination‐based model used: (1) the number of primary care eye examinations conducted annually and (2) the proportion of these that are for myopic young people. The prevalence‐based model used epidemiological data on the age‐specific prevalence of myopia. The proportion of myopic young people progressing ≥0.25 dioptres (D)/year or ≥0.50 D/year was obtained from Irish electronic health records and the recommended review schedule from clinical management guidelines. Results Using the examination and prevalence models, respectively, the estimated number of young people with myopia was 2,469,943 and 2,235,713. The extra workforce required to provide comprehensive myopia management for this target population was estimated at 226–317 FTE at the 0.50 D/year threshold and 433–630 FTE at the 0.25 D/year threshold. Extra visits required for myopia control treatment represented approximately 2.6% of current primary eye care examinations versus 13.6% of hospital examinations. Conclusions Implementing new myopia control treatments in primary care settings over the medium‐term is unlikely to overwhelm the eye care workforce completely. Further increases to workforce, upskilling of current workforce and tools to reduce chair time will help to ensure sustainability of the eye care workforce into the future.