Effect of Three Interventions on Contact Lens Comfort in Symptomatic Wearers: A Randomized Clinical Trial

Abstract

PurposeTo investigate whether carrying out various interventions part way through the day influences comfort in symptomatic daily disposable (DD) contact lens wearers.MethodsA subject-masked, randomized, controlled clinical trial was conducted in thirty symptomatic soft lens wearers who wore their habitual DD contact lenses bilaterally for 12 h on two separate days. Five hours after lens application, one of the following three interventions or a control was performed on each eye: replacing the existing lens with a new lens; removing and reapplying the same lens; performing a ‘scleral swish’; and no action (control). Comfort scores were recorded using SMS text messages every hour following lens application using a 0 (causes pain) to 100 (excellent comfort) scale. Comfort scores before lens application, at 6 mins post-application, and at 6 mins post-intervention were also recorded.ResultsThere was a significant reduction in comfort from pre-lens application to 6 mins post-application for all groups (all p<0.05). Comfort gradually decreased from 6 mins to 5 h after lens application for each group (p<0.0001) with no significant difference between groups over the 5-h period (p = 0.09). There was no significant difference in comfort 6 mins post-intervention for any group (all p>0.05). After the intervention, comfort continued to decline (p<0.0001) with slightly lower mean scores for the control group compared to the new lens group (p = 0.003). Change in comfort relative to pre-intervention (5 h) was similar for all groups (p = 0.81). There was no difference in comfort at 12 h between groups (p = 0.83).ConclusionThis work has confirmed that comfort shows a continual and significant decline over a 12-h wearing period in symptomatic DD contact lens wearers. None of the interventions investigated had any significant impact on end-of-day comfort. These data suggest discomfort in lens wearers is more heavily influenced by changes to the ocular environment rather than to the lens itself.Trial RegistrationControlled-Trials.com ISRCTN10419752 http://www.controlled-trials.com/ISRCTN10419752

Monitoring ocular discomfort using a wrist-mounted electronic logger

“…This increase in the severity of symptoms, has been previously observed later in the lens wearing cycle using both conventional grading and text messaging systems [35,8]. By weighting the LAL events according to their severity, a more meaningful profile through the day was generated, which is thought to relate to how bothersome the contact lens had been, in addition to a single metric (LAI) which summarises the degree of awareness into a single value.…”

“…To more accurately characterise changes in ocular comfort with time and minimise the effect of recall bias, a range of approaches have been developed where such grading scores and/or questionnaires are captured outside of the clinic environment. This typically involves prompting the patient to complete a grading scale and/or questionnaire for ocular comfort at key time-points, typically with the use of a paper diary [7], via text messaging [8] or via the internet [9]. Although this allows the capture of ocular comfort data in the real world, there is often still a requirement for recollection of symptoms, the quality of the data is not always assured (e.g.…”

A single vectored thermal pulsation treatment for meibomian gland dysfunction increases mean comfortable contact lens wearing time by approximately 4 hours per day

“… 4 , 5 The improvements in contact lens design serve, in part, to minimize the discomfort caused by the physical changes, which occur to a contact lens within minutes and hours of placement on the eye (eg, lens dehydration, pre-lens tear film stagnation, and post-lens debris). 6 – 8 However, regardless of lens design optimization, there are ocular tissue changes that occur due to the disruptive presence of any contact lens on the eye. 3 , 6 – 8 Examples of ocular tissue changes that have been reported as strongly correlated with contact lens wear are lid wiper epitheliopathy (LWE), lid parallel conjunctival folds (LIPCOF), and meibomian gland dysfunction (MGD).…”

“… 6 – 8 However, regardless of lens design optimization, there are ocular tissue changes that occur due to the disruptive presence of any contact lens on the eye. 3 , 6 – 8 Examples of ocular tissue changes that have been reported as strongly correlated with contact lens wear are lid wiper epitheliopathy (LWE), lid parallel conjunctival folds (LIPCOF), and meibomian gland dysfunction (MGD). 9 – 11 The mechanisms responsible for these tissue changes can be largely categorized as the result of increased evaporative stress on the tear film, friction between the lid wiper and the ocular surface, and the resulting inflammatory cascades that predictably ensue.…”

Temporal changes in contact lens comfort over a day of wear

“…CLD is associated with ageing of the lens but it also occurs over the day of wear . Patients have been reported to wear their lenses for total wearing times that exceed their comfortable wearing time .…”