Publications

Showing 25 results out of 120 in total.

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 [ Show Abstract ]

SIGNIFICANCE
Vitamin E could be used as a coating with commercial silicone hydrogel lenses to extend the release of various ophthalmic drugs. This concept could provide a promising approach to improve overall ocular therapeutic outcomes for topical ocular drugs.

PURPOSE
This study aimed to develop a contact lens–based ocular drug delivery system using vitamin E as a diffusion barrier to extend the release duration of ciprofloxacin.

METHODS
Five commercial lenses were soaked for 24 hours in various concentrations of vitamin E dissolved in ethanol (0.0125 to 0.2 g/mL). The lenses were loaded with ciprofloxacin for 24 hours in 3 mL of 3 mg/mL of ciprofloxacin/acetic acid solution. The drug release was evaluated in 3 mL of phosphate-buffered saline solution. At t = 0.5, 1, 2, 4, 6, 8, 12, 16, and 24 hours, the amount of ciprofloxacin released was measured using a UV-VIS spectrophotometer at 270 nm.

RESULTS
There was a decrease in ciprofloxacin loading with increasing amounts of vitamin E loaded into the silicone hydrogel lenses. For each lens type, there was an optimal amount of vitamin E loaded that extended the release duration of the drug from 1 hour (without vitamin E) to as long as 16 hours. In contrast, vitamin E loaded into hydrogel lenses had no effect on the amounts of drugs loaded or the release duration.

CONCLUSIONS
Vitamin E can be used as a diffusion barrier with commercially available silicone hydrogel lenses to provide sustained release of ciprofloxacin. The results suggest that vitamin E may form blockages in channels within a silicone hydrogel lens material, thereby forcing a longer path for drugs to diffuse into and out of the lens material. There is an optimal amount of vitamin E that needs to be loaded to extend the release duration, and this is lens material dependent.

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;47(5):102246 [ 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;44(6):1202-1214 [ 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.

Darge,H., Addisu,K. D., Tsai,H-C., Birhan,Y. S., Hanurry,E. Y., Mekonnen,T. W., Gebrie,H. T., Arunagiri,V., Thankachan,D., Wu,T-Y., Chang,H-M., Huang,C-C., Wu,S-Y Actively Targeting Redox-Responsive Multifunctional Micelles for Synergistic Chemotherapy of Cancer ACS Omega 2024;9(32):34268-34280 [ Show Abstract ]

Stimuli-responsive polymeric micelles decorated with cancer biomarkers represent an optimal choice for drug delivery applications due to their ability to enhance therapeutic efficacy while mitigating adverse side effects. Accordingly, we synthesized a digoxin-modified novel multifunctional redox-responsive disulfide-linked poly(ethylene glycol-b-poly(lactic-co-glycolic acid) copolymer (Bi(Dig–PEG-PLGA)-S2) for the targeted and controlled release of doxorubicin (DOX) in cancer cells. Within the micellar aggregate, the disulfide bond confers redox responsiveness, while the presence of the digoxin moiety acts as a targeting agent and chemosensitizer for DOX. Upon self-assembly in aqueous solution, Bi(Dig–PEG-PLGA)-S2 formed uniformly distributed spherical micelles with a hydrodynamic diameter (Dh) of 58.36 ± 0.78 nm and a zeta potential of −24.71 ± 1.01 mV. The micelles exhibited desirable serum and colloidal stability with a substantial drug loading capacity (DLC) of 6.26% and an encapsulation efficiency (EE) of 83.23%. In addition, the release of DOX demonstrated the redox-responsive behavior of the micelles, with approximately 89.41 ± 6.09 and 79.64 ± 6.68% of DOX diffusing from DOX@Bi(Dig–PEG-PLGA)-S2 in the presence of 10 mM GSH and 0.1 mM H2O2, respectively, over 96 h. Therefore, in HeLa cell lines, DOX@Bi(Dig–PEG-PLGA)-S2 showed enhanced intracellular accumulation and subsequent apoptotic effects, attributed to the targeting ability and chemosensitization potential of digoxin. Hence, these findings underscore the promising characteristics of Bi(Dig–PEG-PLGA)-S2 as a multifunctional drug delivery vehicle for cancer treatment.

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;47(5):102255 [ 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;47(5):102276 [ 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, Wong S, Luensmann D, Guthrie S, Woods J, Jones L, Voltz K, Vega J. Evaluation of Scleral Lenses in the Management of Dry Eye Symptoms American Academy of Optometry Meeting, Indianapolis, Nov 8, 2024 [ Show Abstract ][ PDF ]

Purpose: This study aimed to determine if scleral lenses (SLs), either with or without a covalently bonded polyethylene glycol-based lens surface treatment (Hydra-PEG) (Tangible Science), could improve ocular comfort and decrease dryness in symptomatic habitual soft contact lens (CL) wearers and non-CL wearers.

Methods: This prospective, randomized, double-masked, 1-month bilateral cross-over, daily wear study recruited soft CL wearers with a CLDEQ-8 score ≥12 and non-CL wearers with an OSDI score ≥13. Eligible participants were fit with SLs (Onefit MED, Blanchard Contact Lens, a CooperVision Company) and wore one pair with and one pair without lens coating (coated (C-SL)/uncoated (U-SL)) in a randomized order for 1 month each. Participants completed the CLDEQ-8 and rated their overall satisfaction with ocular comfort, dryness, and vision clarity after each wear period using a 0-10 scale (10=best). These data were compared between study SLs and habitual correction (hab-correction), which is habitual CL (hab-CL) or baseline (BL) for non-CL wearers.

Results: 38 completed all study visits and were included in the analysis (20 hab-CL, 18 non-CL). At 1 month, the CLDEQ-8 score improved with both study SLs in comparison to hab-CL (p0.05) and were better than hab-correction (p0.05) but higher with C-SL than hab-CL (p< 0.05) (Hab-CL: 7.3, C-SL: 8.4, U-SL: 7.7). For non-CL wearers, comfort was improved with both study SLs compared to BL (p0.05) (BL: 4.7, C-SL: 7.3, U-SL: 7.1). Overall satisfaction with vision clarity was similar with hab-correction and study SLs (p >0.05) (hab-correction: 7.9, C-SL: 8.2, U-SL: 7.8). However, it was significantly higher with C-SL compared to U-SL for CL wearers (p< 0.05) (C-SL: 8.6, U-SL: 7.7). At study completion, 45% of participants (9 hab-CL and 8 non-CL) expressed interest in future SL wear.

Conclusion: Symptomatic soft CL wearers and non-CL wearers could successfully be fit with Onefit MED SLs. Both study SLs performed well, and only minor differences were seen between study SLs, which were typically in favor of the coated SL. After 1 month, comfort and dryness satisfaction ratings were better with SLs than hab-correction, indicating that SLs are a good option to manage patients with dry eye symptoms, irrespective of whether they are hab-CL or non-CL wearers.

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 [ Show Abstract ]

Purpose: To assess the relationship between eye care practitioners and contact lens patients and to
determine how empathy is associated with patients’ overall satisfaction.


Methods: Multilingual electronic surveys shared by email and on social media in patients’ and practitioners’ groups. Ratings were converted to a numerical scale. The scores were compared using Wilcoxon rank sum tests.


Results: The survey had 804 responses: 68.4% were over 46 years old, and 58.1% were female. Only 770 reported the type of contact lens worn. Of all patients, 10.6% would not recommend their physician due to feeling excluded from decisions (55.3%), lack of personal interest (63.5%), no written recommendations (84%), and unmet expectations (77%). Scleral lens wearers were highly satisfied. Optometrists excelled in care, ratings, relationships, communication, symptom relief, and prevention.


Discussion: The findings highlight the importance of empathy in eye care and its impact on patient experiences. Factors such as contact lens type, physician recommendation, and physician type can influence the level of empathy perceived by patients. Satisfaction varied based on contact lens type, with soft and scleral lens wearers reporting better experiences. Patients valued physicians who listened, explained treatments, showed empathy, and had patient-centered communication and open-ended questions. Optometrists were scored higher than ophthalmologists in several aspects.


Conclusion: Patients, especially scleral lens patients, were generally satisfied with the services and care. Optometrists scored higher than ophthalmologists. Patients would not recommend their physicians mainly because of a lack of empathy.

Fromstein S, Guthrie S, Acs M, Caffery B, Di Marco A, Pal S, Ramdass S, Thakrar V, Zeidenberg M, Jones D, Chow A. Clinical Practice Patterns for the Initial Management of Young Myopic Patients in Canada American Academy of Optometry Meeting, Indianapolis, Nov 7, 2024 [ Show Abstract ]

Purpose: To determine how optometrists in Ontario, Canada are managing myopic pediatric patients over time, and identify factors affecting prescribing decisions.

Methods: In a retrospective chart review, children aged 6-10 who had eye exams between 2017-2021 at optometry practices in Ontario were included. Children were grouped based on presenting spherical equivalent refraction (SER) as myopes (≤-0.50D) or pre-myopes (≤+0.75D). A maximum of five unique charts were selected for each age and visit year for each group, for up to 250 files per practice. Demographic information, refraction and recommended interventions (categorized as standard myopia correction with single vision (SV) glasses or contact lenses (CL); myopia control (MC) treatment with MC glasses or soft CL, ortho-keratology (ortho-K), atropine, bifocals/progressives) were recorded. The present analysis examines how myopes were managed at their initial visit. Data were analyzed using a one-way ANOVA with post-hoc pairwise t-tests with Bonferroni correction.

Results: 2920 patients (1162 myopes) were included from 15 practices across Ontario. All practices offered at least 1 form of myopia control. The majority of clinicians recommended SV glasses/CL as the initial intervention across all years studied (93.8% in 2017 to 59.0% in 2021), although the proportion diminished over time. The most prevalent MC treatments prescribed per year were ortho-K in 2017 (3.9%), MC soft CL in 2018 and 2019 (11.8% and 11.7% respectively) and MC glasses in 2020 and 2021 (12.8% and 30.1% respectively). In later years, clinicians recommended myopia control at earlier levels of myopia; compared to 2017, the mean difference in SER with 2019 was 1.40±0.41D (mean±SE) less myopia, with 2020 1.05±0.41D less myopiaand with 2021 1.08±0.39D less myopia (all p.05). The mean age at which MC glasses (8.6±0.2 years) and MC soft CLs (8.9±0.2 years) were recommended was not statistically different, and similar to the age at which SV glasses/CL were first recommended (8.8±0.1 years; all p>.05). There was no significant difference in the refractive error of patients who were recommended MC glasses (-1.92±0.13D) versus MC soft CL (-2.05±0.15D; mean difference 0.13±0.16D, p>.05). Children with high myopia (< -6D) do not appear to be offered myopia control options as initial management. The lower limit of SER for those offered myopia control was -5.50D (MC glasses) as compared to -7.75D for standard myopia correction (SV glasses/CL).

Conclusion: The prescribing behaviour of clinicians in Ontario, Canada changed from 2017-2021 to incorporate myopia control and interventions are being prescribed at earlier stages of myopia. Neither age nor refractive error seem to impact whether the modality of glasses or CL is recommended for myopia control. Children with high myopia may still benefit from myopia control and are currently underserved.

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;7(9):6286-6296 [ 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.