EC Ophthalmology

The children were originally screened using a battery of diagnostic (indivisible elements of visual performance) and analytical tests (an amalgam of the elements which represented a key skill in the occupation), including the comparative rate of individual character recognition between a “Times” and Gill Sans font (CRST). Those children as risk of reading difficulties were then tested (refracted) and their before (unaided) and after (with their prescription in a trial frame) CRST speeds were measured.

The screening confirmed that all the children had five or more at risk signs of reading difficulty. The CRST results showed 61% of the children had predisposing signs to binocular difficulties and 39% to difficulties caused by visual development. After correction those with binocular vision difficulties showed a 23% improvement in CRST speed on the Times font (p = 1.123E-07, N = 34)) rising to 26% after 5 months. Difficulties with visual development showed a 15% improvement on the Gill Sans font (p = 0.0008, N = 22) rising to 17% after five months. At the five-month interval the profile of the group had changed from predominantly binocular vision difficulties (60.7%) to a majority with visual development difficulties (60.6%).

The likely causes of reading difficulties included unstable eye dominance, accommodation insufficiency, reduced contrast sensitivity, ocular motor balance and cortical fusion problems, as well as straightforward refractive errors including anisometropia. Binocular dysfunction is cited as the primary cause of reading difficulties. Important signs of aetiology include a physiological anatomical displacement of the orbits and/or the globe (horizontal or vertical), accommodation insufficiency, accommodation excess and paresis in one or more of the extra-ocular muscles.

CRST was the more reliable and specific screening tool as a measure of binocular and developmental difficulties. This argues for a more refined approach to the refraction and binocular vision assessment, which takes into account the relationship between the accommodation/vergence reflex and eye dominance, and a direct relationship between vision and its affect on occupation. It is likely that this new approach to optometry will need a post-graduate qualification and professional safeguards.

Stress in the visual system caused by a constant need to access on line information is placing a load on visual physiology with which it is not evolved to deal. It is likely that the majority of the population is suffering from this problem, which is normal and part of the human condition. These problems can be corrected with spectacles and or contact lenses, associated tints and aligning prism.

Keywords: CRST; Comparative Rate of Individual Character Recognition; Times Font; Gill Sans Font; Binocular Vision; Schoolvision; Prism; Differential Chromatic Occlusion; Fixation Disparity; Reading Speed; Developmental Difficulties; Visual Acuity; Dynamic Fixation Diagnostic Tests; Analytical Tests; Eyebright Test; Light Sensitivity; Contrast Sensitivity; Tinted Lenses; Reading Difficulties; Typoglycaemia; Auto-Refraction; Spectacle Correction; Refraction; Sight Test; Information Technology; Stereopsis; Eye Dominance; Aiming; Depth Perception; Drug Treatment; Tracking; Driving Standard; Ocular Physiology; Vision Screening; Information Technology; Myopia; Hyperopia; Convergence Insufficiency; Eye Exercises; Binocular Refraction; Divergence Excess; Rice Test; Ametropia; KPI; Key Performance Indicators; Foveal Ovaloid Maxwell Spots; Accommodation/Vergence Reflex

1. Geraint William Griffiths. “Vision Screening in Primary Education (A Cure for Dyslexia?)”. EC Ophthalmology4 (2022): 10-33.
2. Geraint William Griffiths. “The Comparative Rate of Reading Speed Test (CRST): The importance of Comparing the Rate of individual Character Recognition (Static Tracking Speed) in Serif and Non-Serif Fonts”. EC Ophthalmology8 (2020): 06-17.
3. Geraint William Griffiths. “The Significance of Eye Dominance and Unilateral Fogging of Vision on Sporting Performance”. EC Ophthalmology10 (2020): 37-52.
4. Griffiths GW. “Eye speed, motility and athletic potential”. Optometry Today 42 (2002): 12.
5. Griffiths GW. “Eye Eye Dominance in sport – a comparative study”. Optometry Today 43 (2003): 16.
6. The Moreton Study unpublished report. Available at SVUK Ltd 9 Leicester Road Anstey LE7 7AT 0116 236 3113 www.sportvision.co.uk The Moreton Study published SVUK. Available at SVUK Ltd 9 Leicester Road Anstey LE7 7AT 0116 236 3113.
7. Geraint Griffiths Hemyock Study 2016 published Association of Sport and Schoolvision Practitioners (ASvP) (2016).
8. Griffiths GW. The Comparative Rate of Character Recognition Test - Abbreviated to The Comparative Reading Speed Test (CReST) patent application (not granted because a diagnostic test is not patentable) Published the Association of Sport and Schoolvision Practitioners (ASvP) (2011).
9. Evans BJ and Stevenson SJ. “The Pattern Glare Test: a review and determination of normative values”. Ophthalmic and Physiological Optics4 (2008): 295-309.
10. Creavin AL., et al. Ophthalmic abnormalities and reading impairment Paediatrics (2015).
11. Geraint Griffiths Response to Creavin AL., et al. Ophthalmic abnormalities and reading impairment Paediatrics (2015).
12. James Davies. Cracked- Why psychiatry is doing more harm than good (2013): 38-39.
13. Wilkins AJ., et al. “Rate of Reading Test: its reliability, and its validity in the assessment of the effects of coloured overlays”. Ophthalmic and Physiological Optics 16 (1996): 491-497.
14. North RV. “Work and the eye”. Pub Butterworth Heinemann (1993).
15. Drasdo N and Haggerty CM. “A comparison of the British number plate and Snellen vision tests for car drivers”. Ophthalmic and Physiological Optics 1 (1981): 39-54.
16. Griffiths GW. “Auto-Refractors -Their Use and Usefulness”. Optician 5178196 (1988): 22-29.
17. Ying-Fang Sun., et al. “Brain imaging findings in dyslexia”. Review Pediatrics and Neonatology2 (2010): 89-96.
18. Geraint William Griffiths. “The Aetiology of Colour Preference and its Association with Light Sensitivity, Reduced Contrast Sensitivity and Binocular Deficiency”. EC Ophthalmology6 (2021): 16-31.
19. Lightstone A., et al. “Both coloured overlays and coloured and ophthalmic lenses can improve reading fluency, but their optimal chromaticities differ”. Ophthalmic and Physiological Optics4 (1999): 279-285.
20. Albert Le Floch and Guy Ropars. “Left–right asymmetry of the Maxwell spot centroids in adults without and with dyslexia” (2017).