Related Experiment Video
Updated: Sep 25, 2026

Development of an In Vitro Ocular Platform to Test Contact Lenses
Published on: April 6, 2016
Subjective experience with high-oxygen and low-oxygen permeable soft contact lenses in France
Florence Malet1, Roland Pagot, Catherine Peyre
1Hopital Pelegrin, Bordeaux, France.
Purpose:
This article reports the subjective results of a study comparing extended-wear high-oxygen permeable (HDk) silicone hydrogel soft contact lenses with low-oxygen permeable (LDk) hydroxyethyl methacrylate lenses.
Methods:
Six practitioners in France enrolled 134 subjects in this 4-month, open-label, multicenter, prospective, randomized, cross-over study. Subjects were randomized to receive prescriptions of either an HDk lotrafilcon A or an LDk etafilcon A soft contact lens. Subjects then crossed over to the alternative lens after either 3 months' experience with the HDk lens or 1 month's experience with the LDk lens. Clinical and subjective data were collected at scheduled follow-up visits.
Results:
The clinical data has been reported in a separate article. After 1 month of wear. HDk lenses were rated better than LDk lenses for all aspects of comfort and overall average symptoms. Subjects were satisfied with both lenses, and lens features were comparable through 1 month. The preference was higher for HDk lenses after crossing over, either from or to LDk lenses. Eighty-six percent of HDk and 85% of LDk subjects reported wearing their lenses while sleeping for 7 nights per week during the study. Seventy-seven percent of HDk and 21% of LDk subjects reported wearing their lenses while sleeping for 22 to 31 nights during the study.
Conclusions:
Based on subjective results, therefore, the HDk lens offers another option to patients and practitioners for extended-wear or continuous-wear soft contact lenses.
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