%0 Journal Article
%T Evaluation of Sodium Hyaluronate Lubricating Drops Used before Insertion of Contact Lenses on Symptomatology, Severity, and Intensity of Ocular Dryness
%A Langis Michaud
%A Beno£¿t Frenette
%J ISRN Ophthalmology
%D 2012
%R 10.5402/2012/762784
%X Purpose. This study aimed to evaluate outcomes from the use of a sodium hyaluronate (SH)-based comfort drop, instilled before the insertion of contact lenses, in a population of symptomatic contact lens wearers. Methods. This was a cross-over, open-label, multi-sites study. Subjects were fitted with silicone hydrogel lenses and followed for two months. Before insertion of the lenses, SH drops was instilled in the lens for half of the group. The other half did the same on the second month. Objectives and subjective outcomes were measured and compared before from baseline with the ones collected after usage of SH drops. 1. Introduction As mentioned in the Report of the National Eye Institute [1], dry eye is a disorder of the tear film due to tear deficiency or excessive tear evaporation, which causes damage to the interpalpebral ocular surface, and is associated with symptoms of ocular discomfort. Since contact lenses disrupt the integrity of the tear film and thin out the lipid layer, thus increasing tear evaporation, they can potentially cause symptoms of eye dryness in wearers [2]. Chalmers et al. [3] found that ocular dryness affects 20% of wearers of new-generation silicone hydrogel contact lenses, as well as 24% of wearers of older-generation, low-oxygen permeable (pHEMA) lenses. Brennan and Efron [4] found that 75% of low-oxygen permeable lens wearers report a feeling of discomfort at the end of the day related to dry eye. In general, it is believed that more than 50% of contact lens wearers are symptomatic of dry eye [5]. They may also present with clinical signs of dryness, such as damage to the surface of the eye, as well as instability and/or hyperosmolarity of the tear film; however, the symptoms do not always correlate with the objective signs [1]. In all of these cases, the subject develops discomfort in the absence of any ocular pathology that could trigger the dryness. All other factors being discarded, the contact lens wear must therefore be considered as the most likely etiology of the subject¡¯s symptoms. Subjects with induced ocular dryness by contact lens wear usually tend to drop out from this modality when the benefits of the lenses are outweighed by the discomfort they feel, especially during the last hours of wear, day after day. This is the main reason why 20% of low-oxygen permeable lens wearers and 13% of silicone hydrogel lens [6] wearers stop wearing contact lenses every year. This discontinuation rate represents a continuous loss for the industry and for eyecare professionals, and the quest to find new methods to prevent
%U http://www.hindawi.com/journals/isrn.ophthalmology/2012/762784/