Off the Cuff: March Madness

A survey was conducted with 300 eye care professionals' (ECPs) in the United States, United Kingdom and Japan during November 2017 to gain a better understanding of ECPs perceptions regarding the benefits of silicone hydrogel (SiH) daily disposable contact lenses (DDCL), particularly with respect to health, comfort and patient satisfaction. The survey comprised 34 statements relating to SiH DDCLs, to which the ECPs provided their level of agreement using a six-point Likert scale. A minimum of 70% agreement was set to define majority agreement. Categories of statements included Health, Comfort, Patient Experience and Standard of Care.

ECPs rated the highest levels of agreement to perceptions within the Patient Experiences and Health categories. The six statements receiving the highest ratings were "Silicone hydrogel 1 day lenses satisfy today's patients' demanding lifestyles" (93% agreement); "Silicone hydrogel 1 day lenses are the best choice to safeguard my patients' eye health related to contact lens wear" (92%); "Silicone hydrogel 1 day lenses provide the best benefits to my patients" (92%); "Silicone hydrogel 1 day lenses provide better long-term eye health for my patients than hydrogel 1 day lenses" (91%); "Silicone hydrogel is the healthiest lens material for my daily disposable patients" (90%); and "Silicone hydrogel 1 day lenses provide a better wearing experience for my patients than hydrogel 1 day lenses" (90%).

Researchers wrote that ECPs perceived that SiH DDCLs offered long-term eye health and comfort for the patient, and although the ECPs surveyed would not necessarily prescribe SiH DDCLs to all their patients, they would prescribe them to most of their patients. The results supported the premise that, while ECPs considered SiH 1 day contact lenses as the current "standard of care," the principal barrier continued to be the perceived higher cost of these lenses.

The wettability of silicone hydrogel (SiHy) contact lens (CLs) is crucial for the pre-lens tear film stability throughout the day. Therefore, sessile drop and captive bubble setups were used to study the advancing and receding water contact angles (CA) of four SiHy materials: narafilcon A (TE), senofilcon A (AOD), stenfilcon A (MD) and delefilcon A (DT). TE and AOD have 48% and 38% water content, respectively, and no surface coating. MD (54% water) implements "smart chemistry" with just 4.4% bulk silicone content, while DT has >80% water at its surface. These SiHy were subjected to continuous blink-like air exposure (10 s)/rehydration (1s) cycles for zero, 1, 2, 3, 4, 6, 8, 10, 12, 14, and 16 hours.

The advancing CA, which measured the rehydration propensity of the CL surface, proved to be the most sensitive parameter to discriminate between the samples. The order of performance for the entire time scale was DT > MD >> AOD ≥ TE. The extended desiccation/rehydration cycling increased the differences between the CA of DT and MD compared to AOD and TE.

This suggested that the low Si surface content and the high surface hydration were major determinants of SiHy wettability.

Researchers investigated the clinical efficacy of pinhole soft contact lenses for presbyopia correction. Twenty participants with presbyopia wore pinhole soft contact lenses in the non-dominant eye for two weeks. Manifest refraction, Goldmann binocular visual field tests, contrast sensitivity tests and biomicroscopic examinations were performed along with evaluations of questionnaire responses and binocular corrected distance visual acuity (CDVA), distance-corrected near visual acuity (DCNVA), distance-corrected intermediate visual acuity (DCIVA) and depth of focus, both before and after two weeks of lens wear.

DCNVA at 33cm and 40cm, and DCIVA at 50cm and 70cm showed significant improvements after pinhole lens wear, with no changes in the binocular visual field and binocular CDVA. Contrast sensitivities under photopic and mesopic conditions decreased at some frequencies; however, visual function questionnaire scores significantly improved.

These findings suggested that pinhole contact lenses effectively corrected presbyopia.