+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found

      Does Convergence, Not Accommodation, Cause Axial-Length Elongation at Near?

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          To determine whether convergence rather than accommodation has a primary effect on the changes in axial length and other biometric components during near fixation, we measured the anterior chamber depth, lens thickness, vitreous length and axial length in the right eyes of 124 young male subjects while their left eyes focused at distance (6 m) and near (20 cm). The measurements were performed before and after cycloplegia in the right eye, so we aimed to study biometric components of the eye in the states of accommodation and nonaccommodation, but converging at near. While the left eye focused at near, the axial length increased significantly with and without cycloplegia (p < 0.0005 and p < 0.0005). The vitreous length was the main increasing ocular biometric component at near both with and without cycloplegia (p < 0.044 and p = 0.001, respectively). At near, there was no difference between two mean axial length and two vitreous length measurements both with and without cycloplegia (p = 0.672 and p = 0.595, respectively). Under cycloplegia, anterior chamber depth also increased significantly at near fixation (p = 0.012). Axial elongation at near fixation, mainly due to an increase in vitreous length, may result from the effect of accommodative convergence rather than accommodation itself. Much use of convergence, not accommodation, may be one of the contributing factors in adult onset and adult progression of myopia.

          Related collections

          Most cited references 2

          • Record: found
          • Abstract: not found
          • Article: not found

          Local ocular compensation for imposed local refractive error

           F.A. Miles,  J Wallman (1990)
            • Record: found
            • Abstract: not found
            • Article: not found

            Myopia induced in cats deprived of distance vision during development

             L. Rose,  U. Yinon,  M. Belkin (1974)

              Author and article information

              Ophthalmic Res
              Ophthalmic Research
              S. Karger AG
              August 1999
              26 May 1999
              : 31
              : 4
              : 304-308
              Department of Ophthalmology, Turgut Özal Medical Center, İnönü University, Malatya, Turkey
              55551 Ophthalmic Res 1999;31:304–308
              © 1999 S. Karger AG, Basel

              Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

              Page count
              Tables: 1, References: 22, Pages: 5
              Original Paper


              Comment on this article