Life expectancy of rigid gas permeable and high water content contact lenses

Jones, Lyndon, Woods, Craig A. and Efron, Nathan 1996, Life expectancy of rigid gas permeable and high water content contact lenses, CLAO journal, vol. 22, no. 4, pp. 258-261.

Attached Files
Name Description MIMEType Size Downloads

Title Life expectancy of rigid gas permeable and high water content contact lenses
Author(s) Jones, Lyndon
Woods, Craig A.ORCID iD for Woods, Craig A.
Efron, Nathan
Journal name CLAO journal
Volume number 22
Issue number 4
Start page 258
End page 261
Total pages 4
Publisher Lippincott Williams & Wilkins
Place of publication Philadelphia, Pa.
Publication date 1996-10
ISSN 0733-8902
Keyword(s) contact lens
rigid gas permeable lens materials
daily wear
life expectancy
soft lens
Summary Purpose: The purpose of this study was to evaluate the life expectancy of various rigid gas permeable (RGP) lens materials used on a daily wear basis and to compare these results with the life expectancy of a matched group of soft lens wearers.

Methods: We retrospectively analyzed the records of 600 contact lens wearing patients (300 soft contact lens users and 300 RGP lens users) fit between September 1987 and September 1994. None of the subjects wore lenses on a planned replacement system. For the purposes of the study, RGP lenses were divided into three groups: <40 Dk were considered low-Dk; 41-89 Dk were considered mid-Dk; and >90 Dk were considered high-Dk. All soft lenses were high water content lenses (>60% water content). Lenses were included if they were replaced due to loss, breakage, deposition, or poor wettability but not if replaced because of changes in fit or prescription.

Results; The mean (+SD) life-spans of each lens type in months were 19.9 +/- 17 for low-Dk RGP lenses, 15.9 +/-13.3 for mid-Dk RGP lenses, 9.0+8.2 for high-Dk RGP lenses, and 6.4 +/-5.2 for high water content soft lenses. Statistical analysis using a one-way ANOVA on ranks indicated that these results were statistically significant (P< 0.0001).

Conclusions: Patients should be informed that high-Dk lenses (RGP and soft) provide substantial clinical benefits and that they should expect to replace high-Dk RGP lenses after approximately 6 months. This lends further credence to the use of high-Dk lenses on a planned replacement basis.
Language eng
Field of Research 119999 Medical and Health Sciences not elsewhere classified
Socio Economic Objective 970111 Expanding Knowledge in the Medical and Health Sciences
HERDC Research category C1.1 Refereed article in a scholarly journal
Copyright notice ©1996, Contact Lens Association of Opthalmologists
Persistent URL

Document type: Journal Article
Collections: Faculty of Health
School of Medicine
Connect to link resolver
Unless expressly stated otherwise, the copyright for items in DRO is owned by the author, with all rights reserved.

Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 0 times in TR Web of Science
Scopus Citation Count Cited 17 times in Scopus
Google Scholar Search Google Scholar
Access Statistics: 478 Abstract Views, 1 File Downloads  -  Detailed Statistics
Created: Thu, 30 Aug 2012, 09:29:19 EST

Every reasonable effort has been made to ensure that permission has been obtained for items included in DRO. If you believe that your rights have been infringed by this repository, please contact