Disparity-driven vs blur-driven models of accommodation and convergence in binocular vision and intermittent strabismus

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Horwood, A. ORCID: https://orcid.org/0000-0003-0886-9686 and Riddell, P. ORCID: https://orcid.org/0000-0002-4916-2057 (2014) Disparity-driven vs blur-driven models of accommodation and convergence in binocular vision and intermittent strabismus. Journal of the American Association of Pediatric Ophthalmology and Strabismus, 18 (6). pp. 576-583. ISSN 1091-8531 doi: 10.1016/j.jaapos.2014.08.009

Abstract/Summary

Background. Current models of concomitant, intermittent strabismus, heterophoria, convergence and accommodation anomalies are either theoretically complex or incomplete. We propose an alternative and more practical way to conceptualize clinical patterns. Methods. In each of three hypothetical scenarios (normal; high AC/A and low CA/C ratios; low AC/A and high CA/C ratios) there can be a disparity-biased or blur-biased “style”, despite identical ratios. We calculated a disparity bias index (DBI) to reflect these biases. We suggest how clinical patterns fit these scenarios and provide early objective data from small illustrative clinical groups. Results. Normal adults and children showed disparity bias (adult DBI 0.43 (95%CI 0.50-0.36), child DBI 0.20 (95%CI 0.31-0.07) (p=0.001). Accommodative esotropes showed less disparity-bias (DBI 0.03). In the high AC/A and low CA/C scenario, early presbyopes had mean DBI of 0.17 (95%CI 0.28-0.06), compared to DBI of -0.31 in convergence excess esotropes. In the low AC/A and high CA/C scenario near exotropes had mean DBI of 0.27, while we predict that non-strabismic, non-amblyopic hyperopes with good vision without spectacles will show lower DBIs. Disparity bias ranged between 1.25 and -1.67. Conclusions. Establishing disparity or blur bias, together with knowing whether convergence to target demand exceeds accommodation or vice versa explains clinical patterns more effectively than AC/A and CA/C ratios alone. Excessive bias or inflexibility in near-cue use increases risk of clinical problems. We suggest clinicians look carefully at details of accommodation and convergence changes induced by lenses, dissociation and prisms and use these to plan treatment in relation to the model.

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Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/37442
Identification Number/DOI	10.1016/j.jaapos.2014.08.009
Refereed	Yes
Divisions	Life Sciences > School of Psychology and Clinical Language Sciences > Department of Psychology Life Sciences > School of Psychology and Clinical Language Sciences > Development Life Sciences > School of Psychology and Clinical Language Sciences > Perception and Action
Uncontrolled Keywords	strabismus accommodation convergence AC/A CA/C
Publisher	American Association for Pediatric Ophthalmology and Strabismus
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Funders:	Medical Research Council	The sponsoring bodies who contributed funding for the creation of this item. Example: NERC Example: The Royal Society of Chemistry A pick list of funders may appear as you type in the funder's name in full or as an acronym. Select a correct match to complete the field or type in a new entry in full. For new entries, the full name is preferred.
Projects:	Typical and atypical ocular accommodation and convergence characteristics and relationships over the life span Funded by: Medical Research Council (G0802809 - £565,793) Local Lead (PI): Anna Horwood 31 December 2009 - 31 March 2014	Click Add to select your project (received at Reading) from an autocomplete list.

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Date Deposited:	21 Aug 2014 10:36	Date item deposited into CentAUR
Last Modified:	24 Nov 2024 05:38	Date item last modified

References

1. Schor C. The influence of interactions between accommodation and convergence on the lag of accommodation. Ophthalmic Physiol Opt. 1999;19(2):134-150. 2. Hung G. Linear model of accommodation and vergence can account for discrepancies between AC/A measures using the fixation disparity and phoria methods. Ophthalmic Physiol Opt. 1991;11(3):275-278. 3. Hung GK. Adaptation model of accommodation and vergence. Ophthalmic Physiol Opt. 1992;12(3):319-326. 4. Hung GK. Dynamic model of the vergence eye movement system: simulations using MATLAB/SIMULINK. Comput Methods Programs Biomed. 1998;55:59-68. 5. Horwood A, Riddell P. The use of cues to convergence and accommodation in naïve, uninstructed participants. Vision Research. 2008;48:1613-1624. 6. Fincham E, Walton J. The reciprocal actions of accommodation and vergence. J Physiol. 1957;137:488-508. 7. Tresilian JR, Mon-Williams M. Getting the measure of vergence weight in nearness perception. Exp Brain Res. 2000;132:362-368. 8. Judge S. How is binocularity maintained during convergence and divergence? Eye. 1996;10:172-176. 9. Hasebe S, Nonaka F, Ohtsuki H. Accuracy of accommodation in heterophoric patients: testing an interaction model in a large clinical sample. Ophthalmic Physiol Opt. 2005;25:582-591. 10. Horwood AM, Riddell PM. Differences between naive and expert observers' vergence and accommodative responses to a range of targets. Ophthalmic Physiol Opt. 2010;30:152-159. 11. Horwood A, Riddell P. The Clinical Near Gradient Stimulus AC/A ratio correlates better with the response CA/C ratio than with the response AC/A ratio. Strabismus. 2013;21:140-144. 12. Rosenfield M, Ciuffreda KJ. Accommodative responses to conflicting stimuli. J Opt Soc Am A. 1991;8:422-427. 13. Bruce A, Atchison D, Bhoola H. Accommodation-convergence relationships and age. Invest Ophth Vis Sci. 1995;36:406-413. 14. Schor C. A dynamic model of cross-coupling between accommodation and convergence - simulations of step and frequency responses. Optom Vision Sci. 1992;69:258-269. 15. Seemiller E, Teel D, Babinsky E, Roberts T, Candy TR. The influence of accommodation and vergence coupling during visual development. Journal of Vision. 2012;12:477. 16. Horwood A, Riddell P. Receding and disparity cues aid relaxation of accommodation. Optom & Vis Sci. 2009;86:1276-1286. 17. Horwood A, Riddell P. Hypo-accommodation responses in hypermetropic infants and children. BJOphth 2011;95:231-237. 18. Horwood A, Riddell P. Evidence that convergence rather than accommodation controls intermittent distance exotropia. Acta Ophthalmol Scand. 2012;90:e109-17. doi: 10.1111/j.1755-3768.2011.02313 19. Horwood A, Riddell P. Developmental changes in the balance of disparity, blur and looming/proximity cues to drive ocular alignment and focus. Perception. 2013;42:693-715. 20. Horwood A, Riddell P. Accommodation and vergence response gains to different near cues characterize specific esotropias. Strabismus. 2013 21:155-164. 21. Horwood A, Toor S. Clinical test responses to different orthoptic exercise regimes in typical young adults. Ophth almic Physiol Opt. 2014;34:250-262. 22. Ansons A, Davis H. Diagnosis and management of ocular motility disorders. Oxford: Blackwell Science; 2001: 229-312 23. Kotulak J, Schor C. The effects of optical vergence, contrast, and luminance on the accommodative response to spatially bandpass filtered targets [published erratum appears in Vision Res 1988;27:361]. Vision Res. 1987;27:1797-1806. 24. Tondel GM, Candy TR. Accommodation and vergence latencies in human infants. Vision Res. 2008;48(4):564-576. 25. Tsuetaki TK, Schor CM. Clinical method for measuring adaptation of tonic accommodation and vergence accommodation. Am J Optom Physiol Opt. 1987;64:437-449. 26. Ciuffreda K, Kenyon R. Accommodative vergence and accommodation in normals, amblyopes and strabismics. In: Schor C, Ciuffreda K, eds. Vergence Eye Movements: Basic and Clinical Aspects. Boston: Butterworths; 1983:101-173. 27. Bucci MP, Brémond-Gignac D, Kapoula Z. Speed and accuracy of saccades, vergence and combined eye movements in subjects with strabismus before and after eye surgery. Vision Research. 2009;49:460-469. 28. Kenyon R, Ciuffreda K, Stark L. Dynamic vergence eye movements in strabismus and amblyopia: symmetric vergence. Invest Ophthalmol Vis Sci. 1980;19:60-74. 29. Judge SJ, Cumming BG. Neurons in the monkey midbrain with activity related to vergence eye movement and accommodation. J Neurophysiol. 1986;55:915-930. 30. Tychsen L, Scott C. Maldevelopment of convergence eye movements in macaque monkeys with small- and large-angle infantile esotropia. Invest Ophthalmol Vis Sci. 2003;44:3358-3368. 31. Schor C, Horner D. Adaptive disorders of accommodation and vergence in binocular dysfunction. Ophthalmic Physiological Opt. 1989;9:264-268. 32. Schor CM, Kotulak JC, Tsuetaki T. Adaptation of tonic accommodation reduces accommodative lag and is masked in darkness. Invest Ophthalmol Vis Sci. 1986;27:820-827. 33. Hung GK, Ciuffreda KJ, Rosenfield M. Proximal contribution to a linear static model of accommodation and vergence. Ophthalmic Physiol Opt. 1996;16:31-41. 34. Hung GK, Semmlow JL, Ciuffreda KJ. A dual-mode dynamic model of the vergence eye movement system. IEEE Trans Biomed Eng. 1986;33:1021-1028.

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