Al Atrach,M., Phan.C-M., Jones,L. Extended release of ciprofloxacin from commercial contact lenses containing vitamin E diffusion barriers Optometry and Vision Science 2024;Online ahead of print

Arvind,A., Najappa,R., Gupta,K. K., Macedo-De-Araujo,R. J., Fadel,F. Lid wiper epitheliopathy: Topical review of current identification strategies and future perspectives Contact Lens Anterior Eye 2024;Online ahead of print [ Show Abstract ]

Lid Wiper Epitheliopathy (LWE) is a recognized ocular condition affecting visual quality and ocular comfort, characterized by the damage of the marginal conjunctiva of the upper eyelid. This review critically examines the current strategies for LWE identification and explores the multifactorial etiology of LWE and its association with various ocular surface diseases. A literature review conducted on PubMed identified 67 relevant studies, which were analyzed to enhance understanding of LWE’s diagnostic criteria and its clinical implications, offering future perspectives on improving diagnostic accuracy and patient outcomes.

The association between LWE and contact lens-related discomfort is examined, with studies reporting conflicting findings regarding its prevalence and severity among soft contact lens wearers. Moreover, LWE has been linked to tear film abnormalities, altered tear composition, and eyelid margin abnormalities in non-contact lens wearers, further complicating diagnosis and management.

Current LWE grading systems, including subjective methods and semi-objective approaches, are reviewed, highlighting challenges such as subjectivity, complexity, and variability. Recent advances in LWE grading, including semi-automated methods and photographic scales, show promise but face implementation challenges in clinical settings.

The review concludes by proposing areas for further research, including investigating factors contributing to LWE onset and development, developing more sensitive diagnostic tools, and exploring the impact of LWE on ocular surface health and visual function. Standardization, validation, and innovation in grading systems are emphasized to enhance diagnostic accuracy and improve clinical outcomes for patients with LWE. Ongoing research in LWE grading is essential for addressing diagnostic challenges and optimizing assessment methodologies in clinical practice.

Aziz,A., Kuppusamy,R., Mazumder,K., Hui,A., Maulvi,F., Stapleton,F., Willcox,M. Absorption and attachment of atropine to etafilcon A contact lenses Contact Lens Anterior Eye 2024;Online ahead of print [ Show Abstract ]

Purpose: Myopia (short-sightedness) is a growing vision problem worldwide. Currently atropine eye drops are used to control the progression of myopia but these suffer from potential lack of bioavailability and low ocular residence time. Commercially available myopia control contact lenses are also used to limit myopia progression, but neither atropine nor contact lenses individually completely stop progression. Development of myopia control contact lenses which could deliver therapeutic doses of atropine is thus desirable and may provide increased efficacy. This study was designed to explore the feasibility of attaching atropine to etafilcon A contact lenses through an esterification reaction.

Methods: Carboxylic acid groups on etafilcon A contact lenses were quantified using Toluidine Blue O. The carboxylic acid groups in etafilcon A contact lenses were activated using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC-HCl) and N-hydroxysuccinimide (NHS) crosslinkers after which atropine was added to undergo potential binding via esterification. Atropine was released from lenses by alkaline hydrolysis. Reverse phase high performance liquid chromatography (HPLC) was used to detect and quantify the released atropine and its degradation products in solution. Contact lenses that had not been activated by EDC-NHS (controls) were also examined to determine the amount of atropine that could be absorbed rather than chemically bound to lenses.

Results: Each etafilcon A contact lens contained 741.1 ± 5.5 µg carboxylic acid groups which may be available for esterification. HPLC had a limit of detection for atropine of 0.38 µg/mL and for tropic acid, an atropine degradation product, of 0.80 µg/mL. The limits of quantification were 1.16 µg/mL for atropine and 2.41 µg/mL for tropic acid in NH4HCO3. The etafilcon A lenses adsorbed up to 7.69 μg atropine when incubated in a 5 mg/mL atropine solution for 24 h. However, there was no evidence that atropine could be chemically linked to the lenses, as washing in a high concentration of NaCl removed all the atropine from the contact lenses with no atropine being subsequently released from the lenses after incubating in 0.01 N NH4HCO3.

Conclusions: Etafilcon A contact lenses contain free carboxylic acids which may be an appropriate option for attaching drugs such as atropine. Etafilcon A lenses adsorbed up to 7.69 μg atropine, which would be more than enough to deliver atropine to eyes to control myopia. However, atropine could not be chemically bound to the carboxylic acids of the etafilcon A lenses using this methodology.

Barnett M, Compton J, Pal S, Jones L. The Greatest Contact Lens Course Ever Vision Expo East, New York, USA, Mar 15, 2024

Bose,S., Phan,C.-M., Rizwan,M., Tse,J. W., Yim,E., Jones,L. Fabrication and Characterization of an Enzyme-Triggered, Therapeutic-Releasing Hydrogel Bandage Contact Lens Material Pharmaceutics 2024;16(1):Article 26 [ Show Abstract ]

Purpose: The purpose of this study was to develop an enzyme-triggered, therapeutic-releasing bandage contact lens material using a unique gelatin methacrylate formulation (GelMA+).

Methods: Two GelMA+ formulations, 20% w/v, and 30% w/v concentrations, were prepared through UV polymerization. The physical properties of the material, including porosity, tensile strain, and swelling ratio, were characterized. The enzymatic degradation of the material was assessed in the presence of matrix metalloproteinase-9 (MMP-9) at concentrations ranging from 0 to 300 µg/mL. Cell viability, cell growth, and cytotoxicity on the GelMA+ gels were evaluated using the AlamarBlueTM assay and the LIVE/DEADTM Viability/Cytotoxicity kit staining with immortalized human corneal epithelial cells over 5 days. For drug release analysis, the 30% w/v gels were loaded with 3 µg of bovine lactoferrin (BLF) as a model drug, and its release was examined over 5 days under various MMP-9 concentrations.

Results: The 30% w/v GelMA+ demonstrated higher crosslinking density, increased tensile strength, smaller pore size, and lower swelling ratio (p < 0.05). In contrast, the 20% w/v GelMA+ degraded at a significantly faster rate (p < 0.001), reaching almost complete degradation within 48 h in the presence of 300 µg/mL of MMP-9. No signs of cytotoxic effects were observed in the live/dead staining assay for either concentration after 5 days. However, the 30% w/v GelMA+ exhibited significantly higher cell viability (p < 0.05). The 30% w/v GelMA+ demonstrated sustained release of the BLF over 5 days. The release rate of BLF increased significantly with higher concentrations of MMP-9 (p < 0.001), corresponding to the degradation rate of the gels.

Discussion: The release of BLF from GelMA+ gels was driven by a combination of diffusion and degradation of the material by MMP-9 enzymes. This work demonstrated that a GelMA+-based material that releases a therapeutic agent can be triggered by enzymes found in the tear fluid.

Carrasquillo K, Fadel D, Cardenas N, Flores P . Workshop: Conquering Scleral Lens Complications (Spanish & English session) Global Specialty Lens Symposium, Las Vegas, Jan 19, 2024

Chalmers R, Ng AY, Pucker A. You Can Help Avoid Contact Lens Dropouts NCC, Veldhoven, Netherlands, Mar 11, 2024

Chow,A. H. Y., Mungalsingh,M., Thai,D., Selimos,Z., Yan,S. K., Xu,H., Jones,D. A. Suitability of multifunction devices Myah and Myopia Master for monitoring myopia progression in children and adults Ophthalmic and Physiological Optics 2024;44(5):1017-1030 [ Show Abstract ]

Purpose: To assess the feasibility of using multifunction instruments to measure axial length for monitoring myopia progression in children and adults.

Methods: Axial length was measured in 60 children (aged 6–18 years) and 60 adults (aged 19–50 years) with multifunction instruments (Myah and Myopia Master) and stand-alone biometers (Lenstar LS900 and IOLMaster 700). Repeatability (measurements by the same examiner) and reproducibility (measurements by different examiners) were computed as the within-subject standard deviation (Sw) and 95% limits of agreement (LoA). Inter-instrument agreement was computed as intraclass correlation coefficients. The threshold for detecting myopic progression was taken as 0.1 mm. Measures were repeated only in children following the administration of 1% tropicamide to determine the impact of cycloplegia on axial length.

Results: Overall, the IOLMaster 700 had the best repeatability in children (0.014 mm) and adults (0.009 mm). Repeatability Sw values for all devices ranged from 0.005 to 0.021 mm (children) and 0.003 to 0.016 mm (adults). In children, reproducibility fell within 0.1 mm 95% of the time for the Myah, Myopia Master and IOLMaster 700. Agreement among all devices was classified as excellent (ICC 0.999; 95% CI 0.998–0.999), but the 95% LoA among the Myah, Myopia Master and Lenstar LS900 was ≥0.1 mm. Cycloplegia had no statistically significant effect on axial length (all p > 0.13).
Conclusions: The Myah and Myopia Master multifunction instruments demonstrated good repeatability and reproducibility, and their accuracy was comparable to stand-alone biometers. Axial length measurements using different instruments can be considered interchangeable but should be compared with some caution. Accurate axial length measurements can be obtained without cycloplegia. The multifunction instruments Myah and Myopia Master are as well suited for monitoring myopia progression in children as the stand-alone biometers IOLMaster 700 and Lenstar LS900.

Dang,R., Ehrmann,K., Jalbert,I., Hui,A., Kang,P. Refractive power profiles of commercially available soft multifocal contact lenses for myopia control Ophthalmic and Physiological Optics 2024;Online ahead of print [ Show Abstract ]

Purpose: Lens power profiles can provide valuable insights on the imposed optical defocus and visual experience of contact lens wearers, especially in the context of myopia control. This study measured the refractive power profiles of multifocal soft contact lenses (MFCLs) currently used or that have the potential for use in myopia control using high spatial resolution aberrometry. The instrument's repeatability for determining MFCLs power profiles was also assessed.

Method: The power profiles of 10 MFCLs of various designs (centre-distance, centre-near and extended depth of focus) were measured using the Lambda-X NIMOEVO, a phase shifting Schlieren-based device. Power profiles were graphically expressed as measured power at each chord position and the maximum add power was calculated. The repeatability of the NIMOEVO was expressed as the within-subject standard deviation at each chord position for a subset of five MFCLs.

Results: The measured distance powers differed from nominal powers for more than half of the MFCLs with a definable distance zone. There were variations in the chord position of the distance and near correction zones, rate of power transitions and calculated maximum add between the MFCLs which did not depend on lens design. For half of the MFCLs, the power profile shape was inconsistent between different nominal back vertex powers of the same design. The repeatability of the NIMOEVO was dependent on the lens design, with designs featuring faster rates of power change exhibiting worse repeatability.

Conclusions: Significant differences in MFCL power profiles were found which were not adequately represented in labelling. This is likely due to the small number of parameters used to define lens power characteristics. Eye health care practitioners should be aware of potential differences in power profiles between different MFCLs, which will impact the retinal defocus introduced during lens wear and the wearer's visual experience.

Davison J, Morrison S, Jones L, Compton J. Global Contact Lens Forum: Myopia Control: The Good, The Bad, and The Ugly Vision Expo East, New York, USA, Mar 14, 2024

Efron,N., Morgan,P., Woods,C. A., Jones,D. A., Jones,L., Nichols,J. International trends in rigid contact lens prescribing (2000–2023): An update Contact Lens Anterior Eye 2024;Online ahead of print [ Show Abstract ]

Purpose: Rigid contact lenses have an important role in contact lens practice. The purpose of this work is to update earlier surveys by describing global trends in rigid lens fitting between 2000-2023.

Method: An annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023. Data relating to 342,500 fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of rigid lens fitting, defined as the fitting of any design of a contact lens manufactured in a rigid material.

Results: Overall, rigid lens prescribing increased slightly over time, from 14.2 % of lens fits in 2000 to 15.2 % in 2023 (p < 0.0001). However, post-hoc analysis shows that the change over time is best described as a decline between 2000 and 2012, followed by a steady increase subsequently. There were significant differences in rigid lens prescribing between countries (p < 0.0001). The difference between the percentage of males fitted with rigid lenses, as a proportion of all contact lenses (12.7 %), and females (12.0 %) is significant (p < 0.0001), although not clinically meaningful. Rigid lens wearers are older at fitting than soft lens wearers (38.7 vs 31.3 years,
respectively) (p < 0.0001). Analysis of 5,994 rigid lens fits prescribed currently (2019–2023) were categorised as: corneal sphere – 30 %; scleral and corneo-scleral – 28 %; corneal myopia control/orthokeratology – 21 %; and corneal complex (including toric, multifocal and monovision) – 16 %.

Conclusion: There has been a slight increase in rigid lens fitting during the second decade of this century. This increase is apparently due to a ‘repurposing’ of rigid lenses, with the growth of scleral/corneo-scleral and myopia control/orthokeratology lens fits essentially replacing conventional spherical corneal lens fits.

Efron,N., Morgan,P., Woods,C. A., Jones,D. A., Jones,L., Nichols,J. International trends in prescribing toric soft contact lenses to correct astigmatism (2000–2023): An update Contact Lens Anterior Eye 2024;Online ahead of print [ Show Abstract ]

Purpose
There have been significant advancements in toric soft contact lens design and manufacturing technology, and increased product availability, over the past half a century. The purpose of this work is to update earlier surveys by describing international trends in toric 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 220,934 standard soft daily wear single vision lens fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of toric soft lens fitting.

Results
Overall, toric soft lens prescribing almost doubled over the time-course of this survey, from 24.4 % of standard soft daily wear single vision lens fits in 2000 to 46.2 % in 2023 (p < 0.0001). There were significant differences between countries in toric soft lens prescribing (p < 0.0001). Of all standard soft daily wear single vision contact lenses prescribed to males, 32.0 % were toric soft lenses, compared with 28.7 % for females (p < 0.0001). The mean age of toric soft lens wearers was 30.5 ± 12.5 years, compared to 27.9. ± 12.1 years for spherical soft lens wearers (p < 0.0001). Analysis of 13,582 recent toric soft lens fits (2019–2023, inclusive), in terms of material type and replacement frequency, revealed the following proportions: reusable silicone hydrogel – 51 %; daily disposable silicone hydrogel – 27 %; daily disposable hydrogel – 12 %; and reusable hydrogel – 10 %.

Conclusion
There has been a substantial increase in toric soft lens fitting throughout the 24 years of this survey, to a point whereby almost all clinically significant astigmatism is being corrected among those wearing standard soft daily wear single vision lenses.

Efron,N., Morgan,P., Woods,C. A., Jones,D. A., Jones,L., Nichols,J. International trends in prescribing silicone hydrogel contact lenses for daily wear (2000–2023): An update Contact Lens Anterior Eye 2024;Online ahead of print [ Show Abstract ]

Purpose
Introduced around the turn of the 21st century, silicone hydrogel contact lenses alleviated hypoxic anterior eye complications due to their high oxygen transmissibility. The purpose of this work is to update earlier surveys by describing international trends in silicone hydrogel daily wear contact lens fitting between 2000 and 2023.

Method
An annual contact lens prescribing survey was sent to eye care practitioners in up to 71 countries between 2000 and 2023. Data relating to 260,144 daily wear soft contact lens fits undertaken in 20 countries returning reliable longitudinal data were analysed in respect of silicone hydrogel daily wear contact lens fitting.

Results
There has been a dramatic increase in silicone hydrogel daily wear lens fits (p < 0.0001), increasing from 2.8 % of all daily wear soft lens fits in 2000 to 73.7 % in 2023. Of all daily wear soft contact lenses prescribed to males, 44.6 % were silicone hydrogel lenses, compared with 43.5 % for females (p = 0.0146). The mean age of those wearing silicone hydrogel daily wear lenses was 32.0 ± 14.5 years, compared to 30.4 ± 13.6 years for those wearing daily wear hydrogel lenses (p < 0.0001). Between 2019–2023, the average percentage of fits was – (a) material type: silicone hydrogel – 73 %; mid-water content hydrogels – 13 %; high water content hydrogels – 9 %; and low water content hydrogels – 5 %, and (b) lens design: spherical – 44 %, toric – 32 %, multifocal – 17 %, monovision – 4 %, and ‘other’ – 3 %.

Conclusion
The dramatic increase in silicone hydrogel contact lens prescribing for daily wear has been commensurate with the introduction of multiple lens brands and an ongoing expansion of lens designs, parameters and replacement frequency options. The balance between silicone hydrogel and hydrogel lens prescribing is perhaps starting to approach an equilibrium.

Fadel D. Mastering Scleral, Corneal, and Myopia Management With Contact Lenses! Ontario Association of Optometrists, Symposium, April 12, 2024

Fadel D. Scleral Lenses Know No Bounds Ontario Association of Optometrists, Symposium, April 12, 2024

Fadel D, Barnett M. Masterclass: Scleral Lens Special Applications Global Specialty Lens Symposium, Las Vegas, Jan 18, 2024

Fadel D, Frogozo M. Aspheric Optics in Scleral Lenses for Normal and Diseased Eyes Global Specialty Lens Symposium, Las Vegas, Jan 20, 2024

Fadel D, Wong S, Luensmann D, Guthrie S, Seo J, Woods J, Voltz K, Vega J. The use of Scleral Lenses to Manage Dry Eye Symptoms in Habitual Soft Lens Wearers Global Specialty Lens Symposium, Las Vegas, Jan 20, 2024 [ Show Abstract ]

PURPOSE: To determine if scleral lenses (SLs) with and without Hydra-PEG coating can improve ocular comfort and reduce dryness in symptomatic soft lens wearers.

METHODS: This prospective, randomized, double masked, 1-month bilateral cross over, daily wear study recruited symptomatic soft lens wearers who presented with healthy eyes and a CLDEQ-8 score ≥12 with their habitual contact lens (hab-CL). Eligible participants were fit with SLs (Onefit MED, CooperVision, Inc.) and wore these with and without HydraPEG coating (coated (C-SL) / uncoated (U-SL)) in a randomized order for 1 month per pair. Participants completed a CLDEQ-8 and rated comfort, vision clarity, dryness and handling after each 1-month wear period using a 0-10 scale (10=best) and these data were compared between study SLs and to their hab-CL.

RESULTS: Twenty participants (16F:4M), mean age 29.3±12.4 years [18-64 years] completed the study. The mean refraction of the right eye was Sph -4.69±3.42DS [-15.25 to -0.50DS] and Cyl -0.84±0.79DC [0.00 to -2.75DC]. At 1 month, the CLDEQ-8 score improved with both study SLs in comparison to hab-CL (p0.05) and both were rated better compared to hab-CL (p0.05). At study exit, 9 of the 20 participants requested the SL details to be shared with their eye care professional because they wanted to continue wearing these SLs in future.

CONCLUSIONS: Switching symptomatic soft lens wearers into scleral lenses improved comfort and reduced dryness symptoms after 1 month of wear, with little reduction in ease of lens handling. Subjective ratings were similar with uncoated and HydraPEG coated scleral lenses, with the latter providing slightly better visual clarity.

Fadel,D., Macedo-de-Araújo,R. J., Barnett,M. The Patient-Physician Relationship and Role of Empathic Communication in Contact Lens Practice Journal of Contact Lens Research and Science 2024;8(1):20-36

Ganguly,S., Wulff,D., Phan,C-M., Jones,L., Tang,X. Injectable and 3D Extrusion Printable Hydrophilic Silicone-Based Hydrogels for Controlled Ocular Delivery of Ophthalmic Drugs Applied Bio Materials 2024;Online ahead of print [ Show Abstract ]

While silicone elastomers have found widespread use in the biomedical industry, 3D printing them has proven to be difficult due to the material’s slow drying time, low viscosity, and hydrophobicity. Herein, we arrested the hydrophilic silicone (HS) macrochains into a semi-interpenetrating polymer network (semi-IPN) via an in situ photogelation-assisted 3D microextrusion printing technique. The flow behavior of the pregel solutions and the mechanical properties of the printed HS hydrogels were tested, showing a high elastic modulus (approximately 15 kPa), a low tan δ, high elasticity, and delayed network rupturing. The uniaxial compression tests
demonstrated a nearly negligible permanent deformation, suggesting that the printed hybrid hydrogel maintained its elastic properties. Drug loading and diffusion in the microporous hydrogel are shown via the non-Fickian anomalous transport mechanism, leading to highly tunable loading/releasing profiles (approximately 20% cumulative release) depending on the HS concentration. The drug encapsulation exhibits exceptional stability, remaining intact without any degradation even after a storage period of 1 month. As far as we know, this is the first soft biomaterial based on HS that functions as an exceptional controlled drug delivery device.

Garg P, Shokrollahi P, Phan CM, Jones L. 3D printing of PVA loaded ocular inserts for ocular drug delivery The Association for Research in Vision and Ophthalmology, Seattle, WA, May 9, 2024 [ Show Abstract ][ PDF ]

Purpose: To develop ocular inserts comprised of polyvinyl alcohol (PVA) and gelatin methacrylate (GelMA), using 3D printing technology.

Methods: Inserts were synthesized using a bioink formulation consisting of 10% (w/v) GelMA, 5% (w/v) and 7.5% (w/v) PVA, 0.6% (w/v) lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), and 5% (v/v) yellow dye as a light absorbing agent to improve print resolution. They had a 4mm diameter, 1mm thickness and were fabricated using a commercial masked-stereolithography (mSLA) 3D printer at 95% humidity and 37°C temperature. Morphology of the inserts was investigated by freeze-drying samples and imaging them using a scanning electron microscope (SEM). Release of PVA over 5 hours was studied by incubating at 35°C in PBS in an incubator shaker at 50rpm. The hydrogel samples were freeze dried and their equilibrium swelling was studied in PBS using gravimetric method.

Results: The PVA-loaded ocular inserts were 3D printed within 30 minutes. SEM images showed that 7.5% PVA loaded inserts had more uniform pore size distribution compared to the gels with no PVA. Approximately 37% of PVA was released within the first 2 hrs from the inserts containing PVA, and the release continued up to approximately 4 hrs before reaching a plateau. The release kinetics can be attributed primarily due to passive diffusion. The swelling curves of these hydrogels suggest that they reach equilibrium swelling within 24hr. From the slope of the swelling curve in the first hour, it can be inferred that swelling happens at a slower rate for GelMA/PVA compared to GelMA alone. This slower swelling rate helps to control the release and supports a sustained release of PVA from the combination.

Conclusions: This study showed that a GelMA-PVA based bioink can be used to 3D print ocular inserts that can release PVA for up to 4 hours. Future work will focus on designing 3D scaffolds to increase the release duration of PVA from these gels.

Guthrie,S. E., Luensmann, D., Woods,J., Vega,J., Orsborn,G. Relationships Between Success Factors in Daily Disposable Multifocal Contact Lenses Clinical Optometry 2024;16157-167 [ Show Abstract ]

Purpose: To explore links between subjective comfort and vision in habitual multifocal soft contact lens (MFCL) wearers when refit with daily disposable MFCLs, to determine which factors are relevant for success with MFCLs and evaluate consistency between MFCLs of different designs.

Patients and Methods: This work examined subjective measures in a randomised, participant masked, bilateral wear crossover study at five optometry practices. Fifty-eight habitual MFCL wearers wore stenfilcon A multifocal (stenA-MF; CooperVision Inc) and delefilcon A multifocal (delA-MF; Alcon) for two-weeks. Subjective ratings included satisfaction with comfort and vision and agreement questions.

Results: Agreement with “I would like to wear this MFCL in the future” was taken to indicate success with each MFCL; agreement was significantly higher with stenA-MF. There was strong correlation between agreement responses for “I would like to wear this MFCL in the future” and “MFCL met my needs for vision” with both lenses (p< 0.01). However, it was only with stenA-MF, which had higher agreement responses to both statements (p< 0.05), that responses to these two statements correlated with satisfaction with end-of-day (EOD) comfort (p< 0.01). These differences in correlations between the two lenses are seemingly driven by greater satisfaction with stenA-MF for near and intermediate vision (p< 0.05).

Conclusion: Subjective vision and comfort were only correlated when vision met the needs of most participants. Meeting participants’ needs for vision correlated strongly with wanting to wear a MFCL. Results indicate that meeting vision needs is more important than meeting comfort needs when influencing whether presbyopic patients continue wearing MFCLs.

Guthrie,S., Luensmann,D., Schulze,M., Woods,J., Jones,L. Investigation of Delefilcon A Contact Lenses for Symptomatic Daily Disposable Contact Lens Wearers with Dry Eye Disease: A Prospective Comparative Study Clinical Ophthalmology 2024;Online ahead of print [ Show Abstract ]

Purpose: This prospective comparative study aimed to assess the effects on contact lens comfort, dryness, and wear time when symptomatic daily disposable (DD) contact lens (CL) wearers were refit with delefilcon A (DT1) lenses.

Patients and methods: Thirty five symptomatic DD CL wearers with dry eye disease as determined according to the TFOS DEWS 2 guidelines, were enrolled and completed the study. Participants wore their habitual DD CLs during an initial assessment and were subsequently refit with DT1 for one month. Participants were masked to the study lens type. Subjective ratings of end-of-day comfort and dryness, average wear time, and comfortable wear time were evaluated as primary endpoints.

Results: Of the 35 participants, two participants were classified as aqueous deficient dry eye, while the remaining participants exhibited symptoms primarily due to evaporative causes. The median CLDEQ-8 score for dryness significantly improved from 17 (fair) with habitual lenses to 13 (good) with DT1 lenses (p<0.01). Participants reported significantly better end-of-day comfort (p=0.01) and less end of day dryness (p=0.01) with DT1 compared to their habitual DD lenses. The comfortable wear time was significantly longer with DT1 (8.5 ± 4.1 hours) compared to habitual DD lenses (6.7 ± 3.2 hours) (p=0.04). No significant differences were observed in vision ratings (p=0.07).

Conclusion: Refitting symptomatic DD CL wearers with DT1 resulted in improved end-of-day comfort, reduced end-of-day dryness, and extended comfortable wear time compared to their habitual lenses. These findings suggest that DT1 may offer benefits for symptomatic DD wearers with dry eye disease.

Ho B, Phan CM, Garg P, Shokrollahi P, Jones L. A screening platform for simultaneous evaluation of biodegradation and therapeutic release from an ocular hydrogel and its effect on human corneal epithelial cells The Association for Research in Vision and Ophthalmology, Seattle, WA, May 7, 2024 [ Show Abstract ][ PDF ]

Purpose: To integrate human corneal epithelial cells (HCECs) into a millifluidic screening platform that quantifies biodegradation and release of an entrapped therapeutic from an ocular hydrogel.

Introduction: Biodegradable hydrogels are novel drug delivery methods designed to release entrapped drugs or therapeutics as the gel degrades in situ. The primary challenge in developing biodegradable hydrogels for drug delivery lies in accurately measuring their degradation over time, while simultaneously being able to evaluate the drug release kinetics, which is typically a cumbersome procedure. To properly evaluate the biodegradation of a hydrogel, it is also essential to simulate key factors of the target tissue environment. In the context of the eye, this includes ocular temperature, tear flow, and low tear volume. Recent advances in organ-on-a-chip technologies have made it possible to emulate the human corneal environment. This will allow more accurate measurements of hydrogel degradation rates, subsequent drug or therapeutic release, and ultimately the overall effect on human corneal epithelial cells.

Methods: Gelatin Methacrylate (GelMA) ocular inserts with polyvinyl alcohol (PVA) (10% GelMA 7.5% PVA) were placed inside a custom-designed millifluidic device. Ocular inserts were degraded with up to 200 μg/mL of matrix metallipeptidase 9 (MMP9) for 24 hours at 37oC in PBS. Biodegradation of the ocular insert was quantified using a computational image analysis pipeline. The eluates containing the degradation products were collected to measure PVA released using a spectrophotometric assay, and its toxicity on human corneal epithelial cells (HCECs) was determined by alamarBlueTM assays.

Results: There was significant biodegradation of the GelMA-PVA inserts with increasing concentration of MMP9 in the millifluidic device, which was accurately quantified using a custom computational analysis. Degradation products in the eluate were collected, and there was a ~2-fold increase of PVA released in samples treated with MMP9 compared to the control. The same eluates were non-toxic to HCECs, and interestingly protected HCECs from hyperosmotic conditions mimicking dry eye disease.

Hui A. Research Review - Anti-inflammatory therapy in CLD Contact Lens Spectrum 2024;39, June: 6