Abstract
Purpose: :
This study assessed the effect of topical anaesthetic (TA) on the anterior ocular surface, and examined patient anxiety and comfort during rigid lens (RGP) fitting.
Methods: :
Thirty-four subjects (m=11, f=24, mean age=26 years), with no previous RGP lens wear experience were randomly divided into 2 groups. Group A (N=18) received one drop of 0.5% proxymetacaine (proparacaine) prior to lens insertion at visit 1, while Group B (N=16) received one drop of a placebo (0.9% saline) at visit 1. Subjects completed a visual analogue scale (VAS) to indicate their anxiety prior to RGP lens fitting. Topographical details and examination of the ocular surface, specifically grading of corneal staining and conjunctival hyperaemia (CCLRU grading scales) were recorded. RGP lenses based on the corneal topography were inserted (Quasar, No7 Ltd, Hastings, UK), the lens fit was assessed and the lenses were removed. Corneal staining and conjunctival hyperaemia were reassessed. Subjects completed a further VAS to indicate comfort they had experienced with RGP lenses on the eye. One week later, at visit 2, no drops were instilled prior to lens insertion and the same fit procedure was repeated.
Results: :
At visit 1, no significant difference was found in baseline ocular surface gradings between Groups A and B (p>0.3, Mann-Whitney). Following RGP insertion, conjunctival and limbal hyperaemia, and corneal staining, all increased significantly in both groups (p<0.02, Wilcoxon). At visit 2, following RGP insertion, Group A showed an increase in conjunctival hyperaemia (p=0.028, Wilcoxon) and corneal staining (p=0.02, Wilcoxon), while Group B showed no change in hyperaemia (p>0.357, Wilcoxon), but a significant increase in corneal staining (p=0.012, Wilcoxon). There was no significant difference between Group’s A and B anxiety scores at visit 1 (P=0.155, Mann Whitney). At visit 2, anxiety was significantly reduced in Group A (p=0.017, Wilcoxon), and Group B was unchanged (p=0.861, Wilcoxon). At visit 1, initial RGP comfort scores were higher in group A compared to group B, though this difference was not statistically significant (mean Group A 50.3 + 26.3, Group B 30.3 + 18.8). At visit 2 comfort scores significantly decreased in Group A (p=0.003, Wilcoxon) and increased in Group B (p=0.033, Wilcoxon).
Conclusions: :
RGP lens wear caused ocular hyperaemia on initial fit, but this response reduced at the visit 2. TA use increased lens wear comfort at visit 1, but the lack of previous patient experience resulted in reduced RGP comfort at visit 2. The use of a TA at visit 1 for first-time wearers of RGP lenses resulted in reduced anxiety prior to lens insertion at visit 2.