General pain perception sensitivity, lid margin sensitivity and gas permeable contact lens comfort

Abstract

Background: The non-predictable variability in the capability of sensory adaptation to rigid gas permeable (RGP) contact lenses (CLs) represents a considerable challenge for CL practitioners and patients when choosing this CL type. This study explored if lid margin sensitivity and general pain sensitivity at baseline may help predict experienced subjective comfort of RGP CL wear. Methods: For this prospective clinical cohort study, subjects filled in the Pain Sensitivity Questionnaire and lid margin sensitivity was measured at the lid wiper of the upper and lower lid at baseline, using the Cochet Bonnet aesthesiometer. RGP CL parameters were determined based on corneal topography, with additional use of fluorescein simulation. During the second visit, lid wiper sensitivity measurement was repeated and the RGP CLs were worn for 40 minutes. Upon removal of the CLs, lid wiper sensitivity measurement was repeated and spontaneous CL comfort was rated. Results: Thirty-four subjects participated (mean age: 23.85 AE 5.39 years; 17 male). No correlation could be observed between the baseline lid margin sensitivity and spontaneous CL comfort (r = 0.013, p = 0.9417, upper lid; r = 0.016, p = 0.9277, lower lid). A decrease in lid margin sensitivity was obtained after CL wear (p = 0.0004, upper lid; p = 0.0001, lower lid). A good correlation was observed between Pain Sensitivity Questionnaire score and spontaneous CL comfort (r = 0.62, p = 0.0007). Conclusion: The results of this study suggest that lid margin sensitivity may not play an important role in spontaneous RGP CL comfort. The use of the Pain Sensitivity Questionnaire may well help select patients who are more likely to show good spontaneous tolerance of RGP CLs.

Effect of large diameter and plasma coating on the initial adaptation of gas permeable contact lens fitting for neophytes

“…The finding would suggest that it is not friction with the lens surface that drives initial discomfort with GP wear, rather the bulk of the lens and its interaction with the eyelids and ocular surface. Visual analogue discomfort scores [7] and the Pain Sensitivity Questionnaire [24] have been found to help predict those who will successfully adapt to GP wear, whereas lid sensitivity did not.…”

BCLA CLEAR - Effect of contact lens materials and designs on the anatomy and physiology of the eye

“…Lid margin sensitivity is the highest of all the conjunctival areas [282][283][284]. It is generally considered to be reduced in both rigid corneal and soft lens wear [209,279,281,282,285,286]. The mechanism for this effect is thought to be linked to a neural adaptation from the mechanical interaction between the eyelid margin and the edge of the contact lens during blinking.…”

“…Although an optical benefit is produced by lens wear, the mechanical interaction of the contact lens with the cornea and eyelids can produce a strong foreign body sensation, particularly in rigid corneal lens wear. Thus adaptation to the presence of the lens is a desired side-effect for successful rigid corneal lens wear [21,282,286,[352][353][354]. Adaptation to soft lens wear is not needed to the same extent, but discomfort from soft lens wear raises a different question about how the corneal nerves respond to lens wear and whether a lack of adaptation may be contributing to discomfort [21].…”

BCLA CLEAR - Evidence-based contact lens practice

“…However, other studies suggest on average 2-3 weeks adaptation is required [386,418]. Identifying a potentially successful rigid lens wearer is challenging, but visual analogue scores [418] and the Pain Sensitivity Questionnaire [419] have been found to help, whereas lid sensitivity did not [419]. Anaesthetic use during rigid lens fitting appointments can improve initial comfort [387,415], reduce drop outs [387] and reduce anxiety [415], but a survey of UK ECPs (n = 451) found less than 1.5% used anaesthetic regularly and less than one-third (30.3%) considered it clinically acceptable to do so [420].…”