Twenty healthy volunteers were fitted with a Bausch & Lomb plano O4
bandage contact lens (center thickness, 0.06 mm; water content, 38.6%) in one eye and a CooperVision therapeutic
bandage Permalens (center thickness, 0.24 mm; water content, 70%) in the other eye. Ten received
eyedrops every hour for six hours of a
solution of 224 ml Osmol and the other ten received a
solution of 670 ml Osmol. At the end of the examination period water loss was 21.05% and 20.36% in the
Permalens group with the hypertonic and
hypotonic solutions, respectively, and 8.86% and 10.74% in the Bausch & Lomb lens groups with the hypertonic and
hypotonic solutions, respectively. These values were not significant when compared to those for five control patients (13.75% water loss for the
Permalens and 7.28% for the Bausch & Lomb
contact lens), suggesting that other factors may be more significant in controlling
hydrogel contact lens dehydration.