Abstract
Purpose :
Chronic use of contact lenses (CL) disturbs ocular surface and produces ocular discomfort. We analyzed discomfort self-perception, ocular surface disease index (OSDI), blink frequency (BF), tearing rate (TR), TBUT and corneal sensitivity in young CL wearers.
Methods :
Young subjects (18-25 years old) of both sexes participated voluntarily. CL group wore CL for 2-5 years. Eyeglasses wearers (EG group) with similar refractive errors that never wore CL served as control. Subjects filled in an ad-hoc ocular discomfort self-perception questionnaire (Likert scale survey type) to score the frequency and intensity of ocular surface discomfort and dryness sensations, and an OSDI questionnaire adapted for Spanish speakers. Spontaneous and attentional (visual task) BF, TR, TBUT and corneal sensitivity (explored with a gas esthesiometer, 0-200 ml/min flow, 3s-duration air jets; scored with a VAS) were measured.
Results :
CL group (n=40) showed significantly higher percentage of discomfort than EG group (n=40) using the ad-hoc ocular discomfort self-perception test: 72.5% vs 32.5% for medium-high intensity discomfort; 87.5% vs 57.5% for dryness sensation; 92.5% vs 77.5% for discomfort sensation during the day, and 90% vs 27.5% for the frequency of watering eye sensation. Surprisingly, no differences were found in OSDI questionnaire between CL and EG wearers.
Spontaneous BF was slightly higher in CL than in EG group (22.8±5.1 vs 18.4±3.5 blinks/min). BF decreased significantly during performance of a visual attentional task in both, being this reduction apparently less prominent in CL group (9±3 vs 7.2±3.0 blinks/min). TR and TBUT were significantly lower in CL wearers (22.8±4.6 vs 34.4±1.2 mm; 9.1±3.0 vs 13.2±0.8 s). Intensity/response curves for mechanical corneal sensitivity measured 5 min after CL removal were not significantly modified in CL wearers (n=5) compared with EG users (n=5).
Conclusions :
Young CL users have reduced tear secretion and faster TBUT than non-wearers, which would explain their increased discomfort sensations and blink frequency. Despite being a valid and reliable instrument for measuring the severity of dry eye disease, OSDI was not sensitive enough to detect mild ocular surface alterations in young CL wearers. At this early stage of ocular surface alteration, no changes in mechanical sensitivity, measured with a gas esthesiometer, were evidenced.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.