Despite advances in new designs and materials, contact lens discomfort remains an issue for some patients and contributes to dropout. A team of researchers from Bascom Palmer Eye Institute suggests ocular comfort may be impacted by conjunctival vascular responses in habitual contact lens wearers.

Their study enrolled 27 subjects, comprised of 13 contact lens wearers and 14 non-wearers. The investigators imaged patients’ microvasculature and microcirculation on the temporal bulbar conjunctiva at baseline and again thirty minutes and six hours after wearing daily disposable contact lenses on both eyes.

After contact lens wear, no significant changes were found in vessel diameter, axial and cross-sectional blood flow velocities, blood flow volume, vessel density or complexity in the habitual contact lens wearers. However, non-wearers showed significant increases in axial and cross-sectional blood flow velocities, blood flow volume and vessel density and complexity at both time points of lens wear compared with baseline.

Moreover, non–contact lens wearers had significantly greater changes from baseline to 30 minutes of wear (axial and cross-sectional blood flow velocities and vessel density) and six hours of wear (axial and cross-sectional blood flow velocities, blood flow volume, vessel density and complexity).

Additionally, habitual lens wearers had higher scores on the Contact Lens User Experience questionnaire compared with non-wearers These findings were significantly tied to axial and cross-sectional blood flow velocities and complexity after six hours of lens wear in habitual lens wearers, the study noted.

This is the first study to reveal the relationship between ocular comfort and conjunctival vascular responses in habitual contact lens wearer, the researchers said.

Chen Q, Jiang H, Wang J. Conjunctival vascular adaptation related to ocular comfort in habitual contact lens wearers. Am J Ophthalmol. April 2, 2020. [Epub ahead of print].