Altered visual sensitivity in axial high myopia: A local postreceptoral phenomenon?

Jaworski, Alexandra, Gentle, Alex, Zele, Andrew J., Vingrys, Algis J., & McBrien, Neville A. (2006) Altered visual sensitivity in axial high myopia: A local postreceptoral phenomenon? Investigative Ophthalmology and Visual Science, 47(8), pp. 3695-3702.

View at publisher (open access)


PURPOSE. The present study investigated retinal integrity in high myopia using spatial psychophysical tasks. METHODS. Ten axial high myopes (-8.5 to -11.5 D) and 10 age-matched control subjects (+/- 1.0 D) were recruited. All participants underwent clinical examination and ocular biometry and demonstrated no visible macular disease with visual acuities better than 6/12. Foveal summation thresholds were determined for white and S-cone-isolating spots of various diameters up to 5.4° and spatial contrast sensitivity to luminance sine wave gratings (0.5–9.7 cyc/deg). Data were analyzed after correction for the magnification induced by eye size and correcting lens power. RESULTS. Spatial summation for both white and S-cone-isolating spots showed a generalized loss of sensitivity at all spot sizes in myopes relative to control subjects (P < 0.01). Critical areas at maximum summation were significantly larger in myopes, for S-cone isolating spots only, after image size correction (P < 0.048). Sensitivity at maximum summation correlated negatively with vitreous chamber depth for both targets (P < 0.005). Sensitivities for S-cone and luminance spots also correlated (P < 0.001), indicating widespread dysfunction. Myopes displayed contrast sensitivity losses at high spatial frequencies (P < 0.006) with a normal peak contrast sensitivity. CONCLUSIONS. These data can be interpreted to indicate that highly myopic eyes have either (1) a reduction in the number of receptors and/or a reduction in their sensitivity or, (2) a reduction in the sensitivity of postreceptoral processes. The presence of normal contrast sensitivity at low spatial frequencies indicates dysfunction at a postreceptoral level in high myopes.

Impact and interest:

20 citations in Scopus
Search Google Scholar™
17 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 7469
Item Type: Journal Article
Refereed: Yes
Additional Information: Articles free to read on journal website after 6 months
Additional URLs:
DOI: 10.1167/iovs.05-1569
ISSN: 0146-0404
Subjects: Australian and New Zealand Standard Research Classification > MEDICAL AND HEALTH SCIENCES (110000) > OPTOMETRY AND OPHTHALMOLOGY (111300)
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Copyright Owner: Copyright 2006 Association for Research in Vision and Ophthalmology
Deposited On: 09 May 2007 00:00
Last Modified: 03 Feb 2015 00:47

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page