Accession Number : ADA185578

Title :   A Long Term Study of the Water Content Changes in Three Types of Hydrogel Contact Lenses.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Luehrs, L G

PDF Url : ADA185578

Report Date : May 1987

Pagination or Media Count : 146

Abstract : Sufficient oxygen is required to pass through a hydrogel contact lens for proper corneal metabolism. The permeability of oxygen through such a lens is determined by its specific water content. Thus, it follows that if a hydrogel lens has a decrease in water content there will be a proportional decrease in the amount of oxygen available to the cornea through the lens. This study addressed the change in water content of three lens types: a low water content, CSI-T lens, (n=20); a medium water content, Hydrocurve II lens, (n=25); and a high water content, Permaflex lens, (n=14). The lenses were being measured with a hand refractometer. Water content was measured at ten specific intervals from before lens wear to Day 180. Analysis of the data demonstrated that all three lens types showed a statistically significant decrease in water content. Although there were a few statistically significant points after the 30 minute point, none were deemed of clinical relevance. Key words: Soft contact lens, Oxygen permeability, Oxygen transmissibility, Theses.

Descriptors :   *CONTACT LENSES, *MOISTURE CONTENT, CORNEA, EYEGLASSES, GELS, HANDS, HIGH RATE, INTERVALS, LENSES, METABOLISM, OXYGEN, PERMEABILITY, REFRACTOMETERS, WATER, WEAR

Subject Categories : Optics
      Medical Facilities, Equipment and Supplies

Distribution Statement : APPROVED FOR PUBLIC RELEASE