International trends in prescribing extended wear soft contact lenses (2000-2023): An update.

PURPOSE: Extended wear has long been considered as the ultimate contact lens modality in terms of user convenience. The purpose of this work is to update earlier surveys by describing international trends in extended wear soft lens fitting between 2000 and 2023, inclusive. METHOD: An annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023, inclusive. Data relating to 282,142 soft contact lens fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of extended wear soft lens fitting. RESULTS: Over the duration of the work there was a very small decrease in the prescribing of extended wear soft lenses (p < 0.0001). More detailed inspection shows that prescribing of these lenses steadily increased from 5.8 % of all soft lens fits in 2000 to 11.6 % in 2007, then steadily decreased to 5.2 % in 2023. Of all soft contact lenses prescribed to males, 9.2 % were fitted for extended wear, compared with 6.7 % for females (p < 0.0001). The mean age of extended wear soft lens wearers at fitting was 34.7 ± 14.7 years, compared to 31.1. ± 14.10 years for daily soft lens wearers (p < 0.0001). Analysis of 1,948 recent extended wear soft lens fits (2019-2023, inclusive), in terms of material type, revealed that, on average, 86 % and 14 % of extended wear soft lenses were fitted using silicone hydrogel and hydrogel materials, respectively. CONCLUSION: A modest increase in extended wear soft lens prescribing from 2000 to 2007 corresponded with the introduction of high oxygen transmissibility silicone hydrogel lenses. However, prescribing of this lens type declined thereafter, probably due to ongoing concerns over their increased rate of microbial keratitis, resulting in a prescribing rate in 2023 (5.2%) that was little different to that observed in 2000 (5.8%).

Subjective Symptoms of First-Time Wearers of Verofilcon A Silicone Hydrogel One-Day Disposable Contact Lenses: A First Time Use of Verofilcon A (FTVeA) Study.

Purpose: Verofilcon A, a new daily disposable silicone hydrogel soft contact lens (SCL), is expected to be more comfortable to wear due to its smooth surface. This study aims to compare the comfort level of verofilcon A with eyeglasses in first-time SCL wearers. Methods: A total of 58 new SCL wearers participated in this study. Participants' comfort scores while wearing glasses or verofilcon A were examined at baseline (glasses) and one and four weeks after starting to wear the SCLs. Results: At the end of the one-month study period, no participants had abandoned wearing the SCLs due to discomfort. The vision scores (1-10) for glasses (baseline) and SCLs (week one, week four) were better with SCLs than glasses in the morning (7.9 ± 1.9 vs 8.9 ± 1.3, 9.0 ± 1.2, p<0.01), during the day (8.0 ± 1.6 vs 9.0 ± 1.1, 8.9 ± 1.2, p<0.01), at the end of the day (7.2 ± 2.1 vs 8.5 ± 1.5, 8.7 ± 1.4, p<0.01), and the entire day (7.7 ± 1.7 vs 8.9 ± 1.2, 8.7 ± 1.3, p<0.01). The percentages of participants who agreed that wearing SCLs at week four was as good as or better than glasses in terms of overall vision, peripheral vision, vision at the end of the day, comfort during the day, comfort at the end of the day, less fatigue during the day, and less fatigue at the end of the day were 91.4%, 100.0%, 91.4%, 89.7%, 82.8%, 87.9%, and 89.7%, respectively. Of the participants, 93.1%, 100.0%, and 93.1% felt that the SCLs were easy to wear, more comfortable than expected, and would like to purchase the same lenses in the future, respectively. Conclusion: These findings suggest that verofilcon A is more comfortable than glasses and is effective as an introductory lens for first-time SCL wearers.

Comparison of comfort and tear stability with two novel silicone-hydrogel daily disposable contact lenses.

BACKGROUND: The surface wettability of soft contact lenses (SCLs) affects the wearing comfort. Verofilcon A is a daily disposable silicone hydrogel contact lens with SMARTSURFACE® technology, ensuring high surface wettability. PURPOSE: To evaluate tear stability on the surface of verofilcon A and narafilcon A SCLs and correlate these findings with clinical parameters and patients' discomfort. METHODS: Sixty-two SCL wearers (124 eyes) with SCL discomfort were randomly assigned to use narafilcon A (control SCL) and verofilcon A for 2 weeks each by crossover. The noninvasive tear break-up time (NIBUT) of the naked eye at baseline and pre-lens NIBUT (PL-NIBUT) of the SCL surface after 2 weeks of using each SCL were measured using the DR-1α® dry eye observation device. Corneal superficial punctate keratopathy (SPK) (0-3) and conjunctival hyperemia (0-3), and comfort level of SCL wear (1-10) were also evaluated. RESULTS: NIBUT and PL-NIBUT values were 4.6 ± 2.3 s for the naked eye, 6.6 ± 6.6 s for narafilcon A, and 11.3 ± 3.5 s for verofilcon A. verofilcon A had significantly higher PL-NIBUT than the naked eye and narafilcon A (p < 0.05). SPK (0.16 ± 0.48 vs. 0.00 ± 0.00, p < 0.01) and conjunctival hyperemia (1.15 ± 0.82 vs. 0.49 ± 0.50, p < 0.01) scores were lower when wearing verofilcon A than narafilcon A. The ocular comfort score of wearing SCLs was higher with verofilcon A than with narafilcon A (8.7 ± 1.8 vs. 9.8 ± 0.5, p < 0.01). The ocular comfort score for wearing verofilcon A was higher, regardless of the baseline NIBUT. CONCLUSION: The results of this study showed a consistent surface-wetting advantage of verofilcon A in patients with ocular discomfort. verofilcon A was used comfortably in patients with low NIBUT scores at baseline. The findings suggest that verofilcon A is recommended for SCL wearers experiencing SCL-related dry eye symptoms and discomfort.

Bandage contact lens for in-game corneal abrasion can allow immediate return to play.

While the prevailing treatment for corneal abrasions outside the athletic sphere is the application of a bandage contact lens (BCL), which lessens pain and allows for the maintenance of binocular vision, this is not the case during athletic play. This brief report highlights the advantage of BCLs in treating in-game corneal abrasions, ultimately allowing for an immediate return to play. Additionally, this report summarizes the mechanisms of bandage contact lenses, differentiates them from standard hydrogel contact lenses, and highlights the significant steps necessary to apply the bandage contact lens during an in-game corneal abrasion event. Overall, we link modern ophthalmology clinical practice and sports medicine, allowing for the attenuation of acutely-induced ocular pain to a manageable state.

Patient Satisfaction and Tear Film Break-Up Time After First-Time Wearing of Silicone Hydrogel Contact Lenses.

PURPOSE: The dryness and discomfort associated with soft contact lenses (SCLs) prevent their continued use. Recently, verofilcon A, a new daily disposable silicone hydrogel material SCL, was introduced, which has a high water content (surface water content of 80% or more) that overcomes the low water content drawback of silicone hydrogels. In this study, we evaluated the non-invasive tear break-up time (NIBUT) and comfort level in individuals wearing verofilcon A SCL for the first time. METHODS: We enrolled 42 first-time SCL wearers, comprising 84 eyes. NIBUT was measured using the DR-1α® dry eye observation device at the state of the naked eye before SCL wear (baseline) and at one and four weeks after the first SCL wear. Additionally, we conducted a questionnaire survey during the fourth week to assess the comfort level (0-10) of SCL wear. Results: The NIBUT values were significantly higher at one week (10.8 ± 2.2 s, p<0.01) and four weeks (11.4 ± 2.2 s, p<0.01) after the first SCL wear than those at baseline (5.9 ± 2.0 s). Comfort level in SCL use was significantly higher at one week (9.0 ± 1.1, p<0.01) and four weeks (8.7 ± 1.2, p<0.01) than that at baseline (7.8 ± 1.8), and this level was higher regardless of the baseline NIBUT value. CONCLUSION: Prolonged BUT and increased comfort levels were observed in individuals wearing verofilcon A SCLs. Improvement in tear fluid retention was found to alleviate dry eye and discomfort, suggesting that verofilcon A may be a beneficial introductory lens for first-time SCL wearers.

Association of ocular surface and meibomian gland alterations with silicone hydrogel contact lens wear.

PURPOSE: To evaluate silicone hydrogel contact lens (SH-CL) effects on the meibomian glands, corneal structure, and ocular surface parameters. METHODS: Fifty SH-CL wearers for at least 6 months, and 50 sex and age-matched control subjects were recruited for this cross-sectional study. Visual display terminal (VDT) work and CL wear duration were questioned, ocular surface and tear functions were evaluated using OSDI questionnaire, tear break-up time (TBUT), corneal fluorescein staining, and Schirmer test. Corneal sensitivity was measured with Cochet-Bonnet aesthesiometry. Meibography and in vivo confocal microscopy (IVCM) were performed to evaluate meibomian glands and corneal structure. Intergroup comparisons were made using the Chi-square test, Wilcoxon test, or Kruskal-Wallis test. RESULTS: In the CL group, TBUT was shorter (P = 0.01), corneal fluorescein staining (P = 0.04), OSDI scores (P < 0.001), and meiboscores (P < 0.001) were higher than the control group. The biomicroscopic evaluation revealed meibomian gland dysfunction (MGD) in 34 % of the CL group and 20 % of the control group, which was not statistically significant (P > 0.05). IVCM showed that endothelial cell density was lower (P = 0.01) and polymegethism was higher (P < 0.001) in the CL group. Subbasal nerve density and corneal sensitivity measurements were similar in the two groups (P > 0.05). The longer VDT work duration was associated with increased CFS in the CL group (P = 0.05). CONCLUSION: The results showed that SH-CL wear increased dry eye symptoms and ocular discomfort, especially in longer VDT work duration. Meibography revealed significantly worse results in SH-CL wearers. SH-CL-related ocular discomfort seems to be more associated with MGD rather than neurosensorial alterations.

Characteristics of Pre-Lens Tear Film Behavior in Eyes Wearing Delefilcon A Silicone Hydrogel Water Gradient Contact Lenses.

The pre-lens tear film (PLTF) over (i) delefilcon A silicone hydrogel water gradient (WG; 33-80% from core to surface) contact lenses (CLs) (SHWG-CLs) and (ii) subjects' own non-WG soft CLs (SCLs) (SO-SCLs) was studied in 30 eyes of 30 subjects to assess the hypothesized PLTF stabilization over SHWG-CLs. In both eyes, delefilcon A SHWG-CLs (DAILIES TOTAL1®; Alcon, Fort Worth, TX, USA) or SO-SCLs were worn. After 15 min of wearing each lens, the tear meniscus radius (TMR, mm), lipid-layer interference grade (IG) and spread grade (SG), and non-invasive breakup time (NIBUT, seconds) were evaluated and compared between the SHWG-CLs and the SO-SCLs. The comparison between the SHWG-CL and SO-SCL groups (SHWG-CL and SO-SCL, mean ± SD) revealed that TMRs temporarily decreased and reached a plateau value after 15 min (0.21 ± 0.06; 0.21 ± 0.06) compared to the value prior to CL insertion (0.24 ± 0.08; 0.25 ± 0.08), with no significant difference between the two groups. The NIBUT, IG, and SG values after 15 min of wearing the CLs were (9.7 ± 3.7; 4.7 ± 4.2), (1.0 ± 0.2; 1.8 ± 1.0), and (1.1 ± 0.4; 1.9 ± 1.5), respectively, and all values were significantly better in the SHWG-CL group (p < 0.0001, p = 0.0039, and p < 0.0001, respectively). We found that compared to the SO-SCLs, the maintenance of the PLTF on the SHWG-CLs was supported by the thicker and more stable PLTF.

Managing Pediatric Cataract Patients - The Whole Story: Aphakic Contact Lenses in Children - Techniques and Challenges.

Infantile cataract is one of the major causes of visual impairment in children. This article will discuss some of the techniques, challenges, complications, and compliance issues with aphakic contact lenses.

Study of silicone hydrogel contact lenses' surface reflection characteristics using confocal microscopy.

The physical and chemical properties of contact lenses (CLs) differ significantly from one another. This is already covered by the FDA classification, which divides soft lenses into groups and subgroups for additional characteristics. The differences relate to both the interior and surface of the lens. Several differences in the surface characteristics of individual contact lenses have been studied and demonstrated to date. However, one of their fundamental physical properties, that is light reflection or, quantitatively, reflectance has not been compared. This paper describes the surface differences of a range of silicone-hydrogel (SiHy) lenses using reflectance confocal microscopy. It shows the relationship between the amount of light reflected from the lens surface and the material parameters. Common SiHy lens materials were used in the study, including two lenses with surface modifications. Light incident at the interface between two media (phosphate-buffered saline and lens) with different refractive indices is partially reflected. The normalized results show significant differences between the reflection signals (1 vs 0.07), and that they are not correlated with the refractive index (R2 = 0.5536). For the water content (%H2O), a general trend was observed that the higher the %H2O, the lower the reflection signal is (R2 = 0.8105). The reflection signal and surface modulus show the best correlation. (R2 = 0.9883). The proposed CLs analysis method, using reflectance confocal microscopy, provides data to differentiate between lenses with and without surface modifications.

Biomimetic-Engineered Silicone Hydrogel Contact Lens Materials.

Contact lenses are one of the most successful applications of biomaterials. The chemical structure of the polymers used in contact lenses plays an important role in determining the function of contact lenses. Different types of contact lenses have been developed based on the chemical structure of polymers. When designing contact lenses, materials scientists consider factors such as mechanical properties, processing properties, optical properties, histocompatibility, and antifouling properties, to ensure long-term wear with minimal discomfort. Advances in contact lens materials have addressed traditional issues such as oxygen permeability and biocompatibility, improving overall comfort, and duration of use. For example, silicone hydrogel contact lenses with high oxygen permeability were developed to extend the duration of use. In addition, controlling the surface properties of contact lenses in direct contact with the cornea tissue through surface polymer modification mimics the surface morphology of corneal tissue while maintaining the essential properties of the contact lens, a significant improvement for long-term use and reuse of contact lenses. This review presents the material science elements required for advanced contact lenses of the future and summarizes the chemical methods for achieving these goals.

Corneal sensitivity in silicone hydrogel and rigid gas permeable contact lens wear.

PURPOSE: The aim of this prospective cross-sectional cohort study was to test the effect of silicone hydrogel (SH) and rigid gas permeable (RGP) contact lens (CL) wear on corneal sensitivity, applying the new Swiss Liquid Jet Aesthesiometer for Corneal Sensitivity (SLACS) and the Cochet-Bonnet (CB) aesthesiometer, based on subject feedback (psychophysical method). METHODS: Participants were recruited for three equally large groups: Group A (SH CL), Group B (RGP CL) and Group C (non-CL wearers). Inclusion criteria were healthy eyes and OSDI ≤ 13. Corneal sensory thresholds were determined twice during two visits, with aid of SLACS and CB. RESULTS: 96 participants completed the study (n = 33 in groups A and C, n = 30 in group B); average age in group A: 27.42 ± 6.83 years, group B: 36.90 ± 9.68 years and group C: 26.06 ± 6.19 years. No statistically significant difference in corneal sensitivity was observed between the three groups for either method (p = 0.302 for SLACS, p = 0.266 for CB; Kruskal-Wallis rank sum test). Higher CSTs were obtained for males than for females in both CL groups with SLACS, and with CB only in the RGP CL group (p = 0.041 in Group A, p = 0.006 in Group B with SLACS; p = 0.041 in Group B with CB; bootstrap analysis with age correction and gender balancing). No correlation was observed between CL comfort and corneal sensitivity for neither method applied (for SLACS r = 0.097 and p = 0.51, for CB r = 0.17 and p = 0.15; robust linear mixed model). CONCLUSIONS: No difference in corneal sensitivity with CL compared to non-CL wear was noted in this study. However, lower levels of corneal sensitivity were observed in the male CL groups, warranting further investigation.

Effect of Contact Lens Solutions in Stabilizing the Activity of Tear Lysozyme.

Purpose: Interactions between tear proteins and the interfaces of contact lenses can be complex and can influence contact lens wear success. Tear proteins, including lysozyme, function to maintain the balance of ocular surface homeostasis, as evidenced by the effects of its conformation relative to stabilizing the tear film and its potential impact on corneal epithelial cells. Contact lens manufacturers include components in lens care and blister package solutions to help stabilize the tear film and preserve homeostasis. This in vitro study was performed to evaluate the ability of daily disposable contact lens package solutions to stabilize lysozyme and preserve its native conformation under denaturing conditions. Methods: Lysozyme was added to contact lens solutions sampled from kalifilcon A, etafilcon A, senofilcon A, narafilcon A, nelfilcon A, verofilcon A, delefilcon A, somofilcon A, and stenfilcon A blister packages, then mixed with the protein denaturant sodium lauryl sulfate. Lysozyme activity was evaluated by adding test solutions to a suspension of Micrococcus luteus. Native lysozyme lyses the Micrococcus luteus cell wall, which decreases suspension turbidity. Stabilization of lysozyme activity was determined by comparing suspension turbidity before and after exposure to test solutions. Results: Lysozyme stabilization was 90.7% for kalifilcon A solution, a statistically significant improvement (p < 0.05) compared to phosphate buffered saline (PBS, negative control). No significant improvement was observed with any other contact lens solution (all lysozyme stabilization < 5.00%). Conclusion: The representative tear protein lysozyme was significantly more stable in the novel kalifilcon A contact lens solution containing multiple moisturizers and osmoprotectants than in PBS or other daily disposable contact lens solutions. The lysozyme activity assay provides mechanistic evidence that the kalifilcon A contact lens solution can stabilize proteins under conditions that typically denature proteins, which may contribute to maintaining ocular surface homeostasis.

Contact lenses that transform gold into nanoparticles for prophylaxis of light-related events and photothermal therapy.

This work describes for first time how anisotropic gold nanoparticles (AuNPs) can be spontaneously formed inside preformed contact lenses (CLs) avoiding the use of additional reductant agents (reagent-free) through a precise tunning of the monomeric composition, the saline concentration, and the application of steam heat sterilization. Protocols to generate AuNPs in solution using inorganic or small organic reductants are widely available. Differently, gold precursors interactions with polymer networks have been overlooked and, thus, the interest of chemically cross-linked hydrogels as organic reductants is still to be elucidated. In the ocular field, incorporation of AuNPs to CLs may expand their applications in prophylaxis, therapy and diagnosis. To carry out the work, a variety of hydrogels and commercially available CLs were incubated with gold salt solution without any other chemical reagent. AuNPs formation was monitored by changes in localized surface plasmon resonance (LSPR) bands and quantifying the gold sorbed. Only silicone hydrogels induced AuNPs formation at room temperature in few days; methacrylic acid red-shifted the LSPR band (550-600 nm), while monomers bearing F hindered the reduction. Storage of hydrogels in the gold precursor solution allowed a gradual formation of anisotropic AuNPs, which could be stopped at any time by washing the hydrogel with water. The developed CLs behave as efficient filters against highly penetrant light and also exhibit photoresponsiveness as demonstrated as rapid (10 s), focused mild hyperthermia when irradiated with green, red and NIR lasers.

Soft toric contact lens wear improves digital performance and vision-A randomised clinical trial.

PURPOSE: To compare objective and subjective digital near visual performance and comfort in low to moderate astigmatic participants fitted with toric versus spherical equivalent silicone hydrogel daily disposable contact lenses. METHODS: This was a double-masked, randomised, crossover study. Participants aged 18 to 39 years with astigmatism of -0.75 to -1.50 D were recruited and fitted with toric and spherical contact lenses, in random order. Outcomes were measured at baseline and after 1 week of wear with each contact lens type after the follow-up visits. High- and low-contrast near logMAR visual acuity, automated visual acuity, zoom (%), contrast (%), reading distance (cm), critical print size (logMAR) and reading speed were assessed. Participants also completed the validated Near Activity Visual Questionnaire (NAVQ) and Contact Lens Dry Eye Questionnaire 8 (CLDEQ-8) for each correction type. RESULTS: Twenty-three participants completed the study (74% female, average age 24.4 ± 4.2 years). When participants wore toric contact lenses, near high- and low-contrast visual acuity and automated visual acuity improved by 3-4 letters (all p < 0.03) and participants were able to read faster on an iPad (p = 0.02). Participants were also able to read with 8% less contrast on the iPad with toric lenses (p = 0.01). Participants reported better subjective vision on the overall NAVQ (p = 0.001) and better comfort on the CLDEQ-8 (p = 0.02) with toric lenses. Fewer participants reported difficulty with maintaining focus at near, reading small print, reading labels/instructions, reading the computer display/keyboard and reading post/mail with toric correction. CONCLUSIONS: Toric contact lenses improve comfort, subjective and objective visual performance with digital devices and other near tasks compared with the spherical equivalent correction in participants with low to moderate astigmatism.

Adhesion of Asian Dust Particles to Verofilcon a Soft Contact Lenses.

Purpose: Asian dust poses a serious global health hazard. Airborne particles adhering to contact lenses may cause substantial damage to the ocular surface. The recently released one-day disposable silicone hydrogel soft contact lens (SCL), the verofilcon A, has a smooth surface with SMARTSURFACE® technology, which is designed to prevent adhesion of protein components and foreign bodies. The purpose of this study was to verify the protective quality of verofilcon A SCL against adhesion of Asian dust particles to its surface. Methods: Verofilcon A and etafilcon A (control lens) SCLs were used (n=16 per group), and 0.2 mL of physiological saline containing 0.01 mg/mL of Asian dust particles was dropped on the surface of SCLs, allowed to stand for 1 hour, shaken for 1 minute, and rinsed three times with saline (after rinsing). In addition, the samples were agitated by a vortex mixer for 1 minute and rinsed three times with saline (after vortex). The number of Asian dust particles adhering to the SCLs and percentage of the surface area occupied by the Asian dust particles was determined before washing, after rinsing, and after vortexing. Results: The number of adherent Asian dust particles was lower on verofilcon A SCL (297 ± 116 after rinsing, and 5 ± 14 after vortexing) than on etafilcon A SCL (523 ± 212 after rinsing, p=0.003, and 378 ± 268 after vortexing, p<0.001). The Asian dust adhesion area was also lower on verofilcon A SCL (3.6 ± 2.3% after rinsing and 0.0 ± 0.1% after vortexing than on etafilcon A (10.2 ± 2.1% after rinsing, p=0.002, and 5.2 ± 3.0% after vortexing, p<0.001). Conclusion: These findings indicate that verofilcon A SCL has the property of low adhesion of Asian dust particles. Verofilcon A SCL can be recommended for SCL wearers during windy and Asian dust days.

The impact of a rub and rinse regimen on removal of human coronaviruses from contemporary contact lens materials.

PURPOSE: To assess the influence of contemporary contact lens (CL) materials on human coronavirus attachment and the influence of a rub and rinse step to remove these viruses. METHODS: The binding rates of HCoV-229E and HCoV-OC43 to eight soft CL materials and four rigid gas permeable materials were analyzed. The impact of a rub and rinse step to remove these viruses from all materials was examined. The efficacy of Biotrue (Bausch & Lomb), OPTI-FREE Puremoist (Alcon), Clear Care (Alcon) and cleadew (Ophtecs) to remove virus contamination from two representative soft lens materials (etafilcon A and lotrafilcon B) was also determined. RESULTS: Approximately 102 to 103 infectious viral particles were recovered from each CL material. Although some materials were more prone to coronavirus adhesion, contamination of both viral types was reduced to below the limit of quantification (LQ) from all materials using a simple saline rinse step. Exposure to Clear Care and cleadew reduced the number of infectious viral particles from both etafilcon A and lotrafilcon B to below the LQ, while for Biotrue and OPTI-FREE Puremoist, infectious viral particles were reduced to below the LQ only when additional rub and rinse steps were included. CONCLUSION: Human coronavirus contamination can be easily removed from CL surfaces. Although CL care products containing hydrogen peroxide and povidone-iodine efficiently removed virus contamination from CL surfaces without the need for a rub and rinse step, a full regimen including rub and rinse steps is crucial when using CL care products based on non-oxidative systems.

Brinzolamide-loaded soft contact lens for ophthalmic delivery.

Aim: In this study, brinzolamide (BRZ) was loaded in balafilcon A silicone hydrogel soft contact lens to enhance delivery in glaucoma therapy. Materials & methods: BRZ-loaded soft contact lens was prepared by the soaking method with optimization of pH, temperature and concentration of drug loading solution. Results: At pH 7.4, loading temperature and concentration of 32°C and 3 mg/ml, respectively, enhanced drug loading capacity and release were observed. Diffusional experiments showed Higuchi model of release. BRZ loading brought no appreciable changes in the physical properties of soft contact lens, likewise, maintaining stability. Conclusion: The results demonstrated BRZ loading and delivery through silicone hydrogel soft contact lens which provides a potential alternative in glaucoma therapy.

Aim: In this study, brinzolamide (BRZ) was loaded in soft contact lens to improve drug delivery in glaucoma therapy. Materials & methods BRZ-loaded soft contact lens was prepared by the soaking method modifying pH, temperature and concentration of drug loading solution. Results: At pH 7.4, loading temperature and concentration of 32°C and 3 mg/ml, respectively, enhanced drug loading and release were observed. Diffusion is the main mechanism regulating drug release. BRZ loading brought no changes in the physical properties of soft contact lens, likewise, maintaining stability. Conclusion: The results demonstrated BRZ loading and delivery through soft contact lens which provides a potential alternative in glaucoma therapy.

Bibliometric analysis of the literature relating to silicone hydrogel and daily disposable contact lenses

Purpose: Publication metrics are derived for the fields of silicone hydrogel (SH) and daily disposable (DD) contact lenses.Methods: A search of the Scopus database for papers in the fields of SH and DD contact lenses found 979 SH and 291 DD papers. Subject-specific h-indices for SH lenses (hSH-index) and DD lenses (hDD-index) were derived, in relation to five categories – authors, institutions, countries and journals – to serve as measures of impact. A short list of the most impactful entities was generated for each of the above five categories in the SH and DD fields.Results: A paper entitled “Soft contact lens polymers: An evolution” by Nicholson and Vogt was the most highly cited article (495 citations) in both SH and DD fields. The most impactful entities for the SH and DD fields were: authors – Lyndon Jones (hSH = 33) and Philip Morgan (hDD = 15); institutions – the University of Waterloo (hSH = 37) and the University of New South Wales (hDD = 15); countries – the United States (hSH = 45) and the United Kingdom (hDD = 24); and journals – Optometry and Vision Science (hSH = 33) and Contact Lens and Anterior Eye (hDD = 17). Overall, the SH field (hSH = 64) is far more impactful than the DD field (hDD = 34).Conclusions: Impactful papers, authors, institutions, countries and journals in the SH and DD fields are identified. Optometry is revealed as the leading profession in relation to SH and DD publications. (AU)

Bibliometric analysis of the literature relating to silicone hydrogel and daily disposable contact lenses.

PURPOSE: Publication metrics are derived for the fields of silicone hydrogel (SH) and daily disposable (DD) contact lenses. METHODS: A search of the Scopus database for papers in the fields of SH and DD contact lenses found 979 SH and 291 DD papers. Subject-specific h-indices for SH lenses (hSH-index) and DD lenses (hDD-index) were derived, in relation to five categories - authors, institutions, countries and journals - to serve as measures of impact. A short list of the most impactful entities was generated for each of the above five categories in the SH and DD fields. RESULTS: A paper entitled "Soft contact lens polymers: An evolution" by Nicholson and Vogt was the most highly cited article (495 citations) in both SH and DD fields. The most impactful entities for the SH and DD fields were: authors - Lyndon Jones (hSH = 33) and Philip Morgan (hDD = 15); institutions - the University of Waterloo (hSH = 37) and the University of New South Wales (hDD = 15); countries - the United States (hSH = 45) and the United Kingdom (hDD = 24); and journals - Optometry and Vision Science (hSH = 33) and Contact Lens and Anterior Eye (hDD = 17). Overall, the SH field (hSH = 64) is far more impactful than the DD field (hDD = 34). CONCLUSIONS: Impactful papers, authors, institutions, countries and journals in the SH and DD fields are identified. Optometry is revealed as the leading profession in relation to SH and DD publications.

Stabilization of comfort and visual quality after the insertion of soft contact lenses.

PURPOSE: To evaluate comfort, visual function, and in vivo wettability after the insertion of hydrogel and silicone hydrogel contact lenses for a better understanding of how long practitioners should wait for the initial evaluation of soft contact lenses. METHODS: A short-term prospective, contralateral, randomized, and participant-masked study was carried out. Twenty healthy participants (25.4 ± 2.6 years) were evaluated after the insertion of two different soft contact lenses at different times (1, 5, 10, 20, 30 min). Ocufilcon D (hydrogel) and Somofilcon A (silicone hydrogel) contact lenses were randomly assigned to both eyes of the same participant. Comfort, visual function under photopic conditions in terms of high-contrast visual acuity, low-contrast visual acuity, contrast sensitivity, and in vivo wettability were measured. RESULTS: There was an increase in comfort (p < 0.001), high-contrast visual acuity (p < 0.05), and contrast sensitivity (p < 0.001, only with silicone hydrogel) directly related to time after contact lens insertion. Besides, in vivo wettability suffered a statistically significant deterioration directly related to time with both contact lenses (p < 0.05). Except for comfort and contrast sensitivity, all the parameters stabilized their values 10 min after the insertion of both soft contact lenses. Additionally, in vivo wettability and visual acuity differences were found between hydrogel and silicone hydrogel contact lenses (p < 0.05). CONCLUSIONS: It would be possible to properly evaluate high-contrast visual acuity, low-contrast visual acuity, and in vivo wettability 10 min after the insertion of both soft contact lenses.