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The effect of incipient presbyopia on the correspondence between accommodation and vergence.
Graefes Arch Clin Exp Ophthalmol. 2002 Jun; 240(6):488-94.GA

Abstract

PURPOSE

To investigate the accommodation-convergence relationship during the incipient phase of presbyopia. The study aimed to differentiate between the current theories of presbyopia and to explore the mechanisms by which the oculomotor system compensates for the change in the accommodation-convergence relationship contingent on a declining amplitude of accommodation.

METHODS

Using a Canon R-1 open-view autorefractor and a haploscope device, measurements were made of the stimulus and response accommodative convergence/accommodation ratios and the convergence accommodation/convergence ratio of 28 subjects aged 35-45 years at the commencement of the study. Amplitude of accommodation was assessed using a push-down technique. The measurements were repeated at 4-monthly intervals over a 2-year period.

RESULTS

The results showed that with the decline in the amplitude of accommodation there is an increase in the accommodative convergence response per unit of accommodative response and a decrease in the convergence accommodation response per unit of convergence.

CONCLUSIONS

The results of this study fail to support the Hess-Gullstrand theory of presbyopia in that the ciliary muscle effort required to produce a unit change in accommodation increases, rather than stays constant, with age. Data show that the near vision response is limited to the maximum vergence response that can be tolerated and, despite being within the amplitude of accommodation, a stimulus may still appear blurred because the vergence component determines the proportion of available accommodation utilised during near vision.

Authors+Show Affiliations

Ophthalmic and Physiological Optics Research Group, Neurosciences Research Institute, School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK. f.j.baker@aston.ac.ukNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

12107517

Citation

Baker, Fiona J., and Bernard Gilmartin. "The Effect of Incipient Presbyopia On the Correspondence Between Accommodation and Vergence." Graefe's Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie, vol. 240, no. 6, 2002, pp. 488-94.
Baker FJ, Gilmartin B. The effect of incipient presbyopia on the correspondence between accommodation and vergence. Graefes Arch Clin Exp Ophthalmol. 2002;240(6):488-94.
Baker, F. J., & Gilmartin, B. (2002). The effect of incipient presbyopia on the correspondence between accommodation and vergence. Graefe's Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie, 240(6), 488-94.
Baker FJ, Gilmartin B. The Effect of Incipient Presbyopia On the Correspondence Between Accommodation and Vergence. Graefes Arch Clin Exp Ophthalmol. 2002;240(6):488-94. PubMed PMID: 12107517.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - The effect of incipient presbyopia on the correspondence between accommodation and vergence. AU - Baker,Fiona J, AU - Gilmartin,Bernard, Y1 - 2002/05/15/ PY - 2001/12/20/received PY - 2002/03/20/revised PY - 2002/04/08/accepted PY - 2002/7/11/pubmed PY - 2002/10/4/medline PY - 2002/7/11/entrez SP - 488 EP - 94 JF - Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie JO - Graefes Arch. Clin. Exp. Ophthalmol. VL - 240 IS - 6 N2 - PURPOSE: To investigate the accommodation-convergence relationship during the incipient phase of presbyopia. The study aimed to differentiate between the current theories of presbyopia and to explore the mechanisms by which the oculomotor system compensates for the change in the accommodation-convergence relationship contingent on a declining amplitude of accommodation. METHODS: Using a Canon R-1 open-view autorefractor and a haploscope device, measurements were made of the stimulus and response accommodative convergence/accommodation ratios and the convergence accommodation/convergence ratio of 28 subjects aged 35-45 years at the commencement of the study. Amplitude of accommodation was assessed using a push-down technique. The measurements were repeated at 4-monthly intervals over a 2-year period. RESULTS: The results showed that with the decline in the amplitude of accommodation there is an increase in the accommodative convergence response per unit of accommodative response and a decrease in the convergence accommodation response per unit of convergence. CONCLUSIONS: The results of this study fail to support the Hess-Gullstrand theory of presbyopia in that the ciliary muscle effort required to produce a unit change in accommodation increases, rather than stays constant, with age. Data show that the near vision response is limited to the maximum vergence response that can be tolerated and, despite being within the amplitude of accommodation, a stimulus may still appear blurred because the vergence component determines the proportion of available accommodation utilised during near vision. SN - 0721-832X UR - https://www.unboundmedicine.com/medline/citation/12107517/The_effect_of_incipient_presbyopia_on_the_correspondence_between_accommodation_and_vergence_ L2 - https://dx.doi.org/10.1007/s00417-002-0483-x DB - PRIME DP - Unbound Medicine ER -