The influence of water content of hydrogel contact lenses when fitting patients with ‘tear film deficiency’

Abstract

THe fitting of patients presenting a deficient tear film with hydrogel contact lenses offers a challenge to the professional who must choose between materials having either a low or a high water content. Conflicting conclusions from previous studies concerning the better option led the authors to design a single-centre, double masked, clinical study. Twenty-six subjects deemed to have ‘tear film deficiency’ were fitted with a low water content hydrogel lens on one eye and a high water content one on the other eye. Each subject wore the lenses on a daily wear basis (about 10 hours a day) for 30 days. A detailed questionnaire about subjective considerations, such as comfort and ocular appearance, was completed by the subjects at the end of every day of contact lens wear. The data obtained from these questionnaires and those recorded at three follow-up visits led to the final conclusions. THe questionnaires showed no statistically significant difference between the two eyes in dryness sensation, redness, light sensitivity, blurred vision or overall comfort. During the follow-up visits, no observed sign showed a clinically significant difference between the two eyes. Accordingly, the authors conclude that the water content of hydrogel lens is not a key factor when fitting hydrogel lenses to patients with ‘tear film deficiency’.