Randomized crossover trial of silicone hydrogel contact lenses

Abstract

The aim of the current study is to assess, using new technologies, the interaction of four monthly silicone hydrogel contact lenses on the ocular surface and the comfort over 15 days of use. Methods: Prospective cross-over, randomized and double-masked study including four materials (lotrafilcon-B, samfilcon-A , comfilcon-A and filcom-V3). Clinical examination was performed in the following order: tear meniscus height, first break-up of the tear film, the average time of all tear film breakup incidents, bulbar redness, limbal redness (Keratograph 5M ,Oculus, Germany); central corneal thickness (Pentacam, Oculus, Germany), thermography values (FLIR A325; FLIR Systems Inc., USA), and slit-lamp evaluations, including ocular surface staining. Finally, subjective comfort was obtained from Contact Lens Dry Eye Questionnaire-8. Results: The impact of contact lens wear on the ocular surface didn't show statistically significant changes over time except for corneal and conjunctival staining grades on day 15 compared to day 1 for the comfilcon A group (P = .003 and P = .01, respectively). Contact lens stability and impact on the ocular surface during contact lens wear didn't show statistically significant changes over time except in the case of the comfilcon A material with respect to the irritation item (P = .01). Conclusions: These results suggest that the impact of monthly silicone hydrogel contact lens materials on the ocular surface after and during contact lens wear, contact lens stability over time, and subjective comfort did not reveal any significant changes over 15 days of use for any of the materials.

<p>Comparison and Evaluation of Prelens Tear Film Stability by Different Noninvasive in vivo Methods</p>

“…They concluded that although NIK-DUT did not differ significantly among three types of silicone hydrogel SCLs, their subjective wettability grades differed significantly. 34 Considering the NIKBUT in vivo method did not find any significant difference among commercially available SCLs, 25,26 it may assess the tear film stability on the cornea under the SCL.…”

“…24 They also reported that NIKBUT was not significantly different among three types of silicon hydrogel contact lenses. 25 Mousavi et al reported that the evaluation of the prescribed SCL using conventional methods does not always correspond to the assessment of the tear film stability by NIKBUT. 26 Although the evaluation of prelens tear film stability of SCL plays an important role in identifying CLD, little is known about the comparison of prelens tear film stability measured using different methods.…”

Evaluation of Celligent® Biomimetic Water Gradient Contact Lens Effects on Ocular Surface and Subjective Symptoms

“…Conjunctival redness is an indicator of a potential vascular response to various factors, such as the degree of oxygen transmission, which can lead to corneal hypoxia or allergic reactions and wettability issues [ 12 , 35 ]. Mechanical irritation caused by SH-SCL can trigger an adaptive immune response resulting in serious eye complications and discontinuation of SCL use [ 36 ].…”

BCLA CLEAR - Contact lens complications

“…Conversely, when comparing normal and adverse environmental conditions, a greater reduction in comfort was observed when a SiHy was worn compared to a hydrogel contact lens [386]. Comfort also varies between different SiHy contact lenses [397,398], which suggests that other factors, such as the contact lens surface, design, material modulus and the care solution likely affect comfort [399]. However, contralateral eye studies comparing low modulus hydrogel to higher modulus SiHy contact lenses showed no differences in comfort [400,401].…”