Comparison of tear osmolarity and ocular comfort between daily disposable contact lenses: hilafilcon B hydrogel versus narafilcon A silicone hydrogel

Abstract

The aim of this study was to evaluate tear osmolarity and ocular comfort with two different types of hydrogel daily disposable lenses. The right eyes of 15 first-time contact lens users were included in this prospective study. All eyes wore hilafilcon B silicone hydrogel contact lenses for 8 h (group 1). After 1 week without contact lenses, all eyes wore narafilcon A silicone hydrogel contact lenses for 8 h (group 2). Tear osmolarity measurement was performed before and after 4 and 8 h of each contact lens wear. Ocular comfort was assessed after 4 and 8 h of each contact lens wear. In group 1, the mean baseline, 4- and 8-h tear osmolarity values were 293 ± 10.57, 303.00 ± 10.5 mOsm/L (p = 0.023), and 295.0 ± 1.4 mOsm/L (p > 0.05), respectively. In group 2, the mean baseline, 4- and 8-h tear osmolarity values were 294 ± 13.65, 300.9 ± 11.3 mOsm/L (p = 0.007), and 298.80 ± 7.2 mOsm/L (p > 0.05), respectively. In group 1, the mean comfort score was 7.20 ± 0.45 and 8.60 ± 0.45 at 4 and 8 h, respectively (p = 0.038). In group 2, the mean comfort score significantly decreased from 9.80 ± 0.45 to 7.80 ± 0.84 at 4 h (p = 0.039). Both hydrogel and silicone hydrogel daily disposable contact lenses elevated tear osmolarity during 8 h of contact lens wear. The increase in tear osmolarity with both contact lenses was below the cut-off value for dry eye and was not associated with ocular comfort.

Tear Film Osmolarity in Response to Long-Term Orthokeratology Treatment

“…These findings are in agreement with those of Sarac et al 34 who noted increased TFO in wearers of two different types of daily disposable lenses (hydrogel and silicone hydrogel) over short periods. Osmolarities were similar to our values when measured before CL insertion (293610.97 and 294613.66 mOsmol/L).…”

Comparison of the influence of corneo-scleral and scleral lenses on ocular surface and tear film metrics in a presbyopic population

“…It allows us to hypothesize that since the lenses were of the same material and transmissibility, the TF osmolarity assessment is proven to be an effective diagnostic tool for DED [16][17][18][40][41][42][43]. Tear osmolarity increases have been associated with CL wear in some studies [22,44,45], whereas other studies evidenced no changes [46,47]. According to Efron and colleagues, it is thought increased tear evaporation inducing electrolyte concentration changes could explain tear osmolarity build up associated with CL wear [21,48].…”

The TFOS International Workshop on Contact Lens Discomfort: Report of the Subcommittee on Neurobiology

“…Some studies, [306][307][308][309][310] with one exception, 177 have found that contact lens wear results in increased osmolarity of the tear film or soft contact lenses, although there may not be an association with increased dry eye symptoms. 311 Either way, the sensory effect of tear film hyperosmolarity with contact lens wear may be difficult to measure because the soft contact lens is likely to represent a complex stimulus for the surface neural system. A hyperosmolar tear film that does not penetrate the contact lens is likely to stimulate only conjunctival neurons, which are relatively less sensitive to chemical stimuli compared with the cornea.…”