Author, Subjects, Keywords

Cited Author

 
 
   » By Author or Editor
 » Browse Author by Alphabet
 » By Journal
 » By Subjects
 » By Affiliations
 » By Type
 » By Year
 » By Latest Additions
 
 
   » By Author
 » Top 20 Authors
 » Top 20 Article
 » Top 20 Journal Cited
 » Top 20 Cited
 » Top 20 Author Cited
 » Usage Since Sept 2007


 
 
 

Login | Create Account

The Magnitude of Foveal Suppression During Fixation Disparity in Presbyppic Patients

Faudziah Abd Manan, and Jenkins, T.C.A. and Kaye, N.A. (2003) The Magnitude of Foveal Suppression During Fixation Disparity in Presbyppic Patients. Malaysian Journal of Medical Sciences, 10 (2). pp. 50-59. ISSN 1394195X

Full text not available from this repository.

Official URL: http://www.medic.usm.my/publication/mjms/

Affiliations

Universiti Kebangsaan Malaysia, Faculty of Allied Health Sciences, Dept. of Optometry
University of Bradford, Dept. of Optometry
NA Kaye Ophthalmic Opticians, West Yorkshire, England

Abstract

The characteristics of foveal suppression (FS) in fixation disparity (FD) due to visual stress were investigated and their relationship’s between, age, symptoms, and the effect of temporary elimination of FD using prisms on the degree of the FS were analysed. Forty-five presbyopic subjects (15 without FD and 30 with stress related FD) participated in the study. The subjects underwent comprehensive optometric examination prior to the study. Their FS and FD were measured. The FD was later corrected with ophthalmic prisms, the power of which was equally
divided between the eyes, and the FS was later verified. Age and FS had no significant correlation for subjects without FD (Spearman’s rs = 0.17, p = 0.55,NS) and in subjects with FD (rs = 2.49, p = 0.19, NS), respectively. Correlation between the degree of FS and FD was weak (rs=0.38, p=0.07), however the magnitude of FD significantly increased with age (r=0.27, p=0.04). Subjects with FD had significantly larger degree of FS compared with subjects without FD (Wilcoxon’s Z =-0.25, p=0.01). There was no significant difference in the magnitudes of FD (t = -0.38, p=0.07) and in their degrees of FS (Mann-Whitney U = 1.5, p=0.71) between subjects with and without symptoms. Correcting the FD with prisms generally reduced the degree of FS (Wilcoxon’s Z =1.96, p=0.04), however, significant change in FS only occured in subjects with symptoms (Z=-1.97, p=0.03), but was not significant in subjects without symptoms (Z=-0.70, p=0.48).

Item Type:Journal
Keywords:Fixation disparity, foveal suppression, symptoms, prism correction, Optometry
Subjects:R Medicine
ID Code:899

1. Asher H. Suppression theory of binocular vision. Brit J Ophthal 1953;37:37-49.

2. Blake R., Fox R. Binocular rivalry suppression: on sensitivity of spatial frequency and orientation change. Vis Res 1974;14:687-692.

3. Steinman S.B., Steinman B.A., Garzia R.P. Foundations of binocular vision. A clinical perspective. McGraw-Hill, New York; 200. p 125-130.

4. Schor C.M., Landsman L., Erickson P. Ocular dominance and intraocular suppression of monovision. Am J Optom Physiol Opt 1987;64:723-730.

5. Simpson T. The suppression effect of simulated anisometropia. Ophthal Physiol Opt 1991;11:350-357.

6. Schor C., Erickson P. Pattern of binocular suppression and accommodation in monovision. Am J Optom Physiol Opt 1988;65:853-861.

7. Goersch H. Decompensated heterophoria and its effects on vision. Optician 1979;177:13-16,29.

8. Mallett R.F.J. Fixation disparity. Its genesis and relation to aesthenopia. Ophthal Optician. 1974;14:1156-1168.

9. Sheedy J.E. Actual measurement of fixation disparity and its use in diagnosis and treatment. J Am Optom Assoc 1980;51:1079-1084.

10. Schor C.M. Fixation disparity. A steady state error of disparity induced vergence. Am J Optom Physiol Opt 1980;57:618-631.

11. Schor C. Fixation disparity and vergence adaptation. In: Vergence Eye Movements: Basic and Clinical Aspects . Schor CM and Ciuffreda KJ (Eds), Butterworth, London; 1983. p 465-516.

12. Pickwell D. The binocular stress syndromes. Optometry Today. 1991;March 25: 6.

13. Yekta A.A., Jenkins T. and Pickwell D. The clinical assessment of binocular vision before and after working day. Ophthal Physiol Opt 1987;7:349-352.

14. Pickwell L.D., Jenkins T.C.A, Yekta A.A. The effect of fixation disparity and associated ‘phoria of reading at an abnormally close distance. Ophthal Physiol Opt 1987;7:345-347.

15. Pickwell L.D., Yekta A.A., Jenkins T.C.A. Effects of reading in low illumination on fixation disparity. Am. J. Optom. Physiol. Opt. 1987;61;513-518.

16. Yekta A.A., Pickwell L.D., Jenkins T.C.A. Binocular vision, age and symptoms Ophthal Physiol Opt 1989;9:115-120.

17. Jenkins T.C.A., Pickwell L.D. Yekta A.A. Criteria for decompensation in binocular vision. Ophthal Physiol Opt 1989;9:121-125.

18. Yekta Karizbala A.A. The clinical significance of fixation disparity in binocular vision. PhD Thesis. University of Bradford, UK. 1988. Cited in: Jenkins TCA, Abd-Manan F, Pardhan S, Murgroyd RN 1994 Effect of fixation disparity on distance binocular visual acuity. Ophthal Physiol Opt 1994;14:129-131.

19. Jenkins T.C.A., Abd-Manan F., Pardhan S., Murgroyd R.N. Effect of fixation disparity on distance binocular visual acuity. Ophthal Physiol Opt 1994;14:129-131.

20. Gao H., Hollyfield J.G. Aging of the human retina -differential loss of neurons and retinal pigment epithelium cells. Invest Ophthal Vis Sci 1992;33:1-17.

21. Adams A.J., Wong L.S., Wong L., Gould B. Visual acuity changes with age : some new perspectives. Am J Optom Physiol Opt 1988;65:403-406.

22. Brown B., Yap M.K.H., Fan W.C.S. Decrease in stereoacuity in the seventh decade of life. Ophthal Physiol Opt 1993;1:138-142.

23. Grisham J.D., Sheppard M.M., Tran W.U. Visual symptoms and reading performance. Optom Vis Sci 1993;70:384-391.

24. Mallett R. Techniques of investigation of binocular vision anomalies: In Optometry. Edwards K., Llewellyn R. (Eds) Butterworth, London. 1988. 238-269.

25. Birnbaum M.H. Near point visual stress. A physiological model. J Am Optom Assoc. 1984; 55:825-835.

25. North R., Henson D.B. Adaptation to prism induced heterophoria in subjects with abnormal binocular vision or aesthenopia. Am J Optom Physiol Opt.1981;58:746-752.

Repository Staff Only: item control page
 
 
 
 
 
   
© Copyright 2007 MyAIS Faculty of Computer Science and Information Technology, University of Malaya – All Rights Reserved. Malaysian Abstracting and Indexing System is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.