Abstract
Abstract: :
Purpose: Extensions in Tear Film Break-Up Time (TFBUT) have been shown to increase ocular protection. If an artificial tear substitute is able to extend TFBUT, it may be beneficial when used on a regular basis. The purpose of this study was to examine alterations in tear film stability after instillation of a new novel artificial tear developed by Alcon Laboratories Inc. Methods: Twelve (12) normal subjects were bilaterally dosed with 1 drop of HP-Guar formulation. Tear film break-up-time (TFBUT) was evaluated at baseline (5 minutes prior to product instillation) and again at 5, 10, 15, 20, 30, 45, and 60 minutes post instillation. TFBUT was evaluated using a controlled micro-amount (1 µl) of non-preserved 2% sodium florescein and a digital image recording system with a light filter was used to aid in the evaluation. A Non-Invasive Tear Film Break-Up Time (NIBUT) was performed on ten (10) normal subjects five minutes pre and five minutes post bilateral drop instillation. NIBUT is defined as the time between opening of the eyelids and the first subject reported ocular discomfort. Results: Mean TFBUT was significantly increased at 5, 10, 15, 20, and 30 minutes post instillation compared with baseline. Mean TFBUT, n = 12, was 7.74 seconds at baseline, 17.77 at 5 minutes (P = 0.002), 21.60 at 10 minutes (P = 0.008), 22.58 at 15 minutes (P = 0.008), 12.92 at 20 minutes (P = 0.002), 10.33 at 30 minutes (P = 0.033), 7.70 at 45 minutes (P = 0.935), and 7.10 at 60 minutes post drop instillation (P = 0.091). Mean NIBUT, n = 10, was 7.21 seconds at baseline and 12.57 seconds at 5 minutes post drop instillation (P = 0.040). Conclusions: The results of this study show that the HP-Guar formulation significantly increased TFBUT for 30 minutes post drop instillation. This is corroborated by NIBUT, a subjective measurement given by patients that was extended significantly at 5 minutes post drop instillation. This data suggests that if the HP-Guar product is used on a regular basis, it can protect the ocular surface by extending TFBUT in people who suffer from dry eye.
Keywords: cornea: tears/tear film/dry eye • cornea: clinical science • clinical (human) or epidemiologic studies: tre