Can Simply Wearing Contact Lenses Produce These Responses?
Habitual contact lens (HCL) wearers tended to experience vascular responses on the bulbar conjunctiva that was neither age- nor gender-related, according to a study involving 166 individuals.
Participants included HCL (n=75) and non-contact lens (NCL) wearers (n=91). Investigators imaged their temporal bulbar conjunctiva with a functional slit-lamp biomicroscope, looking specifically at vessel diameter and blood flow velocity (BFVs). They conducted fractal analysis using Dbox as vessel density and D0 as vessel complexity. Among the results:
- BFV of NCL wearers averaged 0.50 mm/s, which negatively correlated with age.
- BFV, vessel diameter, Dbox, and D0 of HCL wearers was significantly higher than NCL wearers.
- In HCL wearers, BFVs positively correlated with contact lens hours of wear/day and contact lens days of wear/week.
- BFV, Dbox, and D0 were not related to contact lens years of wear, power, base curve, or diameter.
The authors concluded that simply wearing contact lenses might be the major reason for the responses they observed.
Hu L, Shi C, Jiang H, Shi Y, Sethi Z, Wang J. Factors affecting microvascular responses in the bulbar conjunctiva in habitual contact lens wearers. Invest Ophthalmol Vis Sci. 2018;59(10):4108-4114. doi: 10.1167/iovs.18-24216.