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Peer-reviewed articles

2021

Morgan,P. B., Murphy,P. J., Gifford,K. L., Gifford,P., Golebiowski,B., Johnson,L., Makrynioti,D., Moezzi,A. M., Moody, K., Navascues-Cornago,M., Schweizer,H., Swiderska,K., Young,G., Willcox,M. CLEAR - Effect of contact lens materials and designs on the anatomy and physiology of the eye Contact Lens Anterior Eye 2021;44(2):192-219 [ Show Abstract ]

This paper outlines changes to the ocular surface caused by contact lenses and their degree of clinical significance. Substantial research and development to improve oxygen permeability of rigid and soft contact lenses has meant that in many countries the issues caused by hypoxia to the ocular surface have largely been negated. The ability of contact lenses to change the axial growth characteristics of the globe is being utilised to help reduce the myopia pandemic and several studies and meta-analyses have shown that wearing orthokeratology lenses or soft multifocal contact lenses can reduce axial length growth (and hence myopia).

However, effects on blinking, ptosis, the function of Meibomian glands, fluorescein and lissamine green staining of the conjunctiva and cornea, production of lid-parallel conjunctival folds and lid wiper epitheliopathy have received less research attention. Contact lens wear produces a subclinical inflammatory response manifested by increases in the number of dendritiform cells in the conjunctiva, cornea and limbus. Papillary conjunctivitis is also a complication of all types of contact lenses. Changes to wear schedule (daily disposable from overnight wear) or lens materials (hydrogel from SiHy) can reduce papillary conjunctivitis, but the effect of such changes on dendritic cell migration needs further study. These changes may be associated with decreased comfort but confirmatory studies are needed. Contact lenses can affect the sensitivity of the ocular surface to mechanical stimulation, but whether these changes affect comfort requires further investigation.

In conclusion, there have been changes to lens materials, design and wear schedules over the past 20+ years that have improved their safety and seen the development of lenses that can reduce the myopia development. However, several changes to the ocular surface still occur and warrant further research effort in order to optimise the lens wearing experience.

2019

Moezzi,A. M., Varikooty,J., Luensmann,D., Schulze,M., Ng,A. Y., Karkkainen,T., Xu,J., Jones,L. The short-term physiological impact of switching reusable silicone hydrogel wearers into a hydrogel daily disposable multifocal Clinical Ophthalmology 2019;13:1193-1202 [ Show Abstract ]

Purpose: To evaluate ocular physiological responses to etafilcon A multifocal (etMF) daily disposable (DD) lenses after 4 weeks of wear, when switching from habitual silicone hydrogel (SiHy) daily wear.
Method: A single-arm, open-label, bilateral dispensing study was conducted in 39 habitual spherical SiHy wearers (14 hyperopes; 25 myopes). Clinical visits occurred with habitual SiHy (control) at baseline and after 4 weeks of etMF DD open-eye lens wear at exit. Objective limbal/bulbar hyperemia using the Oculus K5M (0–4) and subjective grading of lid wiper epitheliopathy (LWE) (0–4) were tested for non-inferiority (NI), using a margin of 1 grade. Corneal thickness along a 10 mm cord was measured using the Visante OCT and tested for NI using a 30 μm margin. Corneal staining area was graded (0–100%).
Results: The least-square mean differences (LSMD) and 95% confidence interval (95% CI) between etMF DD and habitual SiHy in central and peripheral corneal thickness (μm) were 3.64 (−2.0, 9.29) and 3.0 (−7.72, 13.72) in hyperopic, and 3.56 (−0.66, 7.78) and 6.40 (−1.62, 14.42) in myopic subjects. The LSMD (95% CI) for bulbar and limbal hyperemia were −0.08 (−0.19, 0.02) and −0.01 (−0.12, 0.09) in hyperopes, and 0.04 (−0.03, 0.12) and 0.04 (−0.04, 0.11) in myopes. The LSMD (95% CI) for LWE were 0.11 (−0.39, 0.60) and 0.30 (−0.07, 0.67) for hyperopes and myopes, respectively.
Conclusions: No clinically significant differences in a variety of physiological responses were found when habitual reusable SiHy daily wear subjects were refitted into hydrogel etMF, when the subjects were followed for 4 weeks.

2018

Moezzi,A., Hutchings,N., Fonn,D., Simpson,T. L. Mixed Model Analysis of Between-Subject Variability in Overnight Corneal Swelling and Deswelling With Silicone Hydrogel Lenses Invest Ophthalmol Vis Sci 2018;59(6):2576-85 [ Show Abstract ]

PURPOSE: To model between subject variability of corneal swelling (CS) and deswelling after overnight wear of silicone hydrogel (SiHy) contact lenses.

METHODS: A total of 29 neophyte subjects wore 12 SiHy lenses with central transmissibility range of 31 to 211 Dk/t units on separate nights, in random order, and on one eye only. The contralateral eye served as the control. Central corneal thickness was measured using digital optical pachymetry before lens insertion, immediately after lens removal on waking, then 20, 40 minutes, 1, 2, and 3 hours later. Mixed modelling was conducted for simultaneous analysis of group and between-subject effects of CS and deswelling.

RESULTS: The best model for overnight CS versus Dk/t was linear with a random intercept showing constant between-subject differences in CS for different Dk/t values. The best fit for corneal deswelling versus time was a curvilinear random intercept and random slope model. About 90% of the total between-subject deswelling variance in either lens or control eyes was due to the intercept variability with much less (∼10%) being due to the variability of the individual deswelling rate (slope). Subject age, sex, and ametropia were not predictors of individual corneal swelling in the swelling versus Dk/t analysis. Age, however, was a significant (inverse) predictor of the rate of corneal deswelling, only in lens-wearing eyes.

CONCLUSIONS: A large proportion of variability in corneal swelling is because of subject-specific differences in corneal response to hypoxia. This shows that "low swellers" and "high swellers" actually do exist.

Wallerstein,A., Jackson,W.B., Chambers,J., Moezzi,A., Lin,H., Simmons,P.A Management of post-LASIK dry eye: a multicenter randomized comparison of a new multi-ingredient artificial tear to carboxymethylcellulose Clinical Ophthalmology 2018;12:839-848 [ Show Abstract ]

Purpose: To compare the efficacy and safety of a preservative-free, multi-ingredient formulation of carboxymethylcellulose 0.5%, hyaluronic acid 0.1%, and organic osmolytes (CMC-HA), to preservative-free carboxymethylcellulose 0.5% (CMC) in the management of postoperative signs and symptoms of dry eye following laser-assisted in situ keratomileusis (LASIK).
Methods: This was a double-masked, randomized, parallel-group study conducted in 14 clinical centers in Canada and Australia. Subjects with no more than mild dry eye instilled CMC-HA or CMC for 90 days post-LASIK. Ocular Surface Disease Index© (OSDI; primary efficacy measure), corneal staining, tear break-up time (TBUT), Schirmer’s test, acceptability/tolerability surveys, and visual acuity were assessed at screening and days 2, 10, 30, 60, and 90 post-surgery. Safety analyses included all enrolled.
Results: A total of 148 subjects (CMC-HA, n=75; CMC, n=73) were enrolled and assigned to receive treatment, and 126 subjects completed the study without any protocol violations. Post-LASIK, dry eye signs/symptoms peaked at 10 days. OSDI scores for both groups returned to normal with no differences between treatment groups at day 90 (P=0.775). Corneal staining, Schirmer’s test, TBUT, and survey results were comparable. Higher mean improvements in uncorrected visual acuity were observed in the CMC-HA group at all study visits, reaching statistical significance at day 30 (P=0.013). Both treatments were well tolerated.
Conclusion: CMC-HA-containing artificial tears relieved post-LASIK ocular dryness as well as CMC alone, and demonstrated incremental benefit in uncorrected vision, with a favorable safety profile. Results support use of CMC-HA eye drops to reduce signs and symptoms of ocular dryness post-LASIK.

2016

Cox,S. M., Berntsen,D. A., Chatterjee,N., Hickson-Curran,S. B., Jones,L. W., Moezzi,A. M., Morgan,P. B., Nichols,J. J. Eyelid margin and meibomian gland characteristics and symptoms in lens wearers Optometry and Vision Science 2016;93(8):901-908 [ Show Abstract ]

Purpose. To describe the lid margin characteristics of contact lens wearers and relate them to comfort during lens wear. Methods. Three study sites enrolled habitual contact lens wearers. Subjects completed the Comfort domain of the Contact Lens User Experience (CLUE) questionnaire, and each eye was graded for the presence of mucocutaneous junction (MCJ) displacement, lid margin irregularity, and lid margin vascularity. Examiners counted the number of meibomian gland (MG) orifices in the central centimeter of the lower eyelid and the number of those that showed pouting/plugging and vascular invasion. MG expressibility was graded according to the Shimazaki schema. Subjects were grouped based on presence/ absence of each characteristic, total number of orifices (=5 vs. 0). Descriptive statistics are reported. A linear model was used to assess the fixed effect of each characteristic on combined CLUE score and each CLUE statement, if the effect on combined CLUE score showed p < 0.10. Results. The study included 203 subjects (67.5% female) with mean age (±SD) of 30.3 ± 9.6 years. The most commonly observed characteristics were orifice pouting/plugging, compromised MG expressibility, and lid margin vascularity (35.0, 30.3, and 20.4%, respectively). MCJ displacement and MG expressibility had an effect on the combined CLUE score such that individual CLUE statements were analyzed (p = 0.01 and p = 0.06, respectively). MCJ displacement had an effect on comfort upon insertion (p = 0.01), comfort after 5 minutes (p = 0.03), end-of-day comfort (p = 0.01), and ability to maintain ocular moisture (p = 0.030). MG expressibility had a significant effect on general comfort (p = 0.01), comfort throughout the day (p = 0.02), and the ability to maintain ocular moisture (p = 0.02). Conclusions. MCJ displacement and MG expressibility have an effect on contact lens comfort. © Copyright 2016 American Academy of Optometry.

Moezzi,A. M., Varikooty,J., Schulze,M., Ngo,W., Lorenz,K. O., Boree,D., Jones,L. W. Corneal Swelling with Cosmetic etafilcon A Lenses versus No Lens Wear Optometry and Vision Science 2016;93(6):619-628 [ Show Abstract ]

Purpose: To determine if the use of pigments or adding polyvinyl pyrrolidone during the fabrication of 1-DAY ACUVUE DEFINE (AD) brand contact lenses impacts open-eye corneal swelling compared with no lens wear (NLW). Methods: A partial double-masked, randomized, bilateral crossover study was conducted in 24 Asian subjects using AD, 1-DAY ACUVUE DEFINE with Lacreon (ADL), NLW, and a control lens with no tint (1-DAY ACUVUE MOIST [AM]). Central corneal thickness was measured before insertion and immediately after removal after 8 ± 1 h of open-eye wear using an optical pachymeter in one eye. Corneal thickness along a 10-mm cord was measured in the contralateral eye using the Visante optical coherence tomographer (OCT). Corneal swelling was tested for noninferiority using a 5% margin. The endothelial bleb response was measured at baseline and 20 min after lens insertion using specular microscopy. Subjective grading of corneal staining and limbal/bulbar hyperemia were also monitored. Results: After 8 ± 1 h of open-eye wear, central corneal swelling across the study lenses with either optical pachymeter or OCT methods was negligible. Peripheral corneal swelling least-square mean differences with OCT were -0.03% (95% confidence interval [95% CI], -0.65 to 0.58%) and -0.26% (95% CI, -0.87 to 0.36%) between AD and ADL and the control lens (AM), respectively, and 1.67% (95% CI, 1.06 to 2.29%) and 1.45% (95% CI, 0.84 to 2.06%) between AD and ADL and NLW, respectively. No endothelial blebs were observed. No clinically significant differences were distinguished between the lenses and NLW for corneal staining and limbal/bulbar hyperemia. Conclusions: After 8 ± 1 h of open-eye wear, central and peripheral corneal swelling along the horizontal meridian with AD, ADL, AM, and NLW were equivalent. These results confirm that the addition of polyvinyl pyrrolidone or pigments to etafilcon A to obtain a limbal ring design have no impact on corneal swelling or limbal/bulbar hyperemia during normal open-eye wear.

2015

Moezzi,A. M., Fonn,D., Varikooty,J., Simpson,T. L. Overnight corneal swelling with high and low powered silicone hydrogel lenses Journal of Optometry 2015;8(1):19-26 [ Show Abstract ]

Purpose To compare central corneal swelling after eight hours of sleep in eyes wearing four different silicone hydrogel lenses with three different powers. Methods Twenty-nine neophyte subjects wore lotrafilcon A (Dk, 140), balafilcon A (Dk, 91), galyfilcon A (Dk, 60) and senofilcon A (Dk, 103) lenses in powers -3.00, -10.00 and +6.00 D on separate nights, in random order, and on one eye only. The contra-lateral eye (no lens) served as the control. Central corneal thickness was measured using a digital optical pachometer before lens insertion and immediately after lens removal on waking. Results For the +6.00 D and -10.00 D, lotrafilcon A induced the least swelling and galyfilcon A the most. The +6.00 D power, averaged across lens materials, induced significantly greater central swelling than the -10.00 and -3.00 D (Re-ANOVA, p < 0.001), (7.7 ± 2.9% vs. 6.8 ± 2.8% and 6.5 ± 2.5% respectively) but there was no difference between -10.00 and -3.00 D. Averaged for power, lotrafilcon A induced the least (6.2 ± 2.8%) and galyfilcon A the most (7.6 ± 3.0%) swelling at the center (Re-ANOVA, p < 0.001). Central corneal swelling with +6.00 D was significantly greater than -10.00 D lens power despite similar levels of average lens transmissibility of these two lens powers. Conclusions The differences in corneal swelling of the lens wearing eyes are consistent with the differences in oxygen transmission of the silicone hydrogel lenses. In silicone hydrogel lenses central corneal swelling is mainly driven by central lens oxygen transmissibility.

2014

Moezzi,A. M., Fonn,D., Varikooty,J., Simpson,T. L. Overnight corneal swelling with high and low powered silicone hydrogel lenses Journal of Optometry 2014;8(1):19-26 [ Show Abstract ]

Purpose: To compare central corneal swelling after eight hours of sleep in eyes wearing four different silicone hydrogel lenses with three different powers. Methods: Twenty-nine neophyte subjects wore lotrafilcon A (Dk, 140), balafilcon A (Dk, 91), galyfilcon A (Dk, 60) and senofilcon A (Dk, 103) lenses in powers -3.00, -10.00 and +6.00 D on separate nights, in random order, and on one eye only. The contra-lateral eye (no lens) served as the control. Central corneal thickness was measured using a digital optical pachometer before lens insertion and immediately after lens removal on waking. Results: For the +6.00 D and -10.00 D, lotrafilcon A induced the least swelling and galyfilcon A the most. The +6.00 D power, averaged across lens materials, induced significantly greater central swelling than the -10.00 and -3.00 D (Re-ANOVA, p < 0.001), (7.7 ± 2.9% vs. 6.8 ± 2.8% and 6.5 ± 2.5% respectively) but there was no difference between -10.00 and -3.00 D. Averaged for power, lotrafilcon A induced the least (6.2 ± 2.8%) and galyfilcon A the most (7.6 ± 3.0%) swelling at the center (Re-ANOVA, p < 0.001). Central corneal swelling with +6.00 D was significantly greater than -10.00 D lens power despite similar levels of average lens transmissibility of these two lens powers. Conclusions: The differences in corneal swelling of the lens wearing eyes are consistent with the differences in oxygen transmission of the silicone hydrogel lenses. In silicone hydrogel lenses central corneal swelling is mainly driven by central lens oxygen transmissibility. © 2013 Spanish General Council of Optometry.

2012

Luensmann,D., Moezzi,A., Peterson,R. C., Woods,C., Fonn,D. Corneal staining and cell shedding during the development of solution-induced corneal staining Optometry and Vision Science 2012;89(6):868-874 [ Show Abstract ]

Purpose. This non-dispensing cross-over study was conducted to determine if lenses presoaked in Opti-Free RepleniSH (OFR) or ReNu MultiPlus (RMP) cause solution-induced corneal staining (SICS) and subsequent cell sloughing before the typical 2 h in vivo examination point. Methods. Study lenses (PureVision) were worn bilaterally by 13 participants for periods of 15, 30, 60, and 120 min using two different contralateral care regimen pairings. The lens worn on the test eye was soaked overnight in either OFR or RMP and the control eye in Clear Care (CC). After lens removal, corneal staining was rated on a scale of 0 (negligible) to 100 (severe) for four peripheral quadrants and the central region, and the differential global staining score was calculated by subtracting baseline staining scores. Following the staining assessment, corneal cells were collected from the ocular surface using a non-contact irrigation system to determine ocular cell shedding rates. Results. Differential global staining score with OFR was greater than CC with the differences being statistically significant at 30 and 60 min (p 0.05). Conclusions. SICS occurred earlier but to a significantly lower degree when PureVision lenses were presoaked in OFR compared with RMP, while lenses presoaked in CC did not cause SICS. Ocular surface cell shedding after lens removal was not impacted by lens wear durations of ≤2 h. © 2012 American Academy of Optometry.

2011

Moezzi,A. M., Fonn,D., Varikooty,J., Richter,D. Distribution of overnight corneal swelling across subjects with 4 different silicone hydrogel lenses Eye and Contact Lens 2011;37(2):61-65 [ Show Abstract ]

Purpose: To determine distribution of central corneal swelling (CCS) across subjects after 8 hr of sleep in eyes wearing silicone hydrogel lenses with various oxygen transmissibility (Dk/t) values and in eyes without lenses. Methods: Twenty-nine neophytes wore lotrafilcon A (Dk, 140), balafilcon A (Dk, 91), galyfilcon A (Dk, 60), and senofilcon A (Dk, 103) lenses in powers -3.00, -10.00, and +6.00 diopters on separate nights, in random order, and on 1 eye only. The contralateral eye (no lens) served as the control. Central corneal thickness was measured using a digital optical pachometer before lens insertion and immediately after lens removal on waking. Results: The average difference between the mean (7%) and the median (6.8%) CCS of all lenses was only 0.2%, suggesting a normal distribution. There was no correlation between the mean and the range of the CCS (r=0.058, P=0.766). Normal CCS distributions were also found with each lens-wearing eye and the control eye (P>0.20 for all). There was a significant correlation between lens-wearing eye and control eye (r=0.895, P<0.001) and between lotrafilcon A and each of the other 3 lenses for mean CCS across the study participants (P<0.001 for all). Conclusions: Distribution of corneal swelling in both lens-wearing eye and control eye followed a normal curve. An individual's corneal swelling response seems to be independent of lens type. © 2011 Lippincott Williams & Wilkins.

2006

Dumbleton,K., Keir,N., Moezzi,A., Feng,Y., Jones,L., Fonn,D. Objective and subjective responses in patients refitted to daily-wear silicone hydrogel contact lenses Optometry and Vision Science 2006;83(10):758-768 [ Show Abstract ]

PURPOSE. Silicone hydrogel (SiH) lenses offer many physiological advantages for daily wear (DW) in addition to the continuous-wear modality for which they were originally developed. The purpose of this study was to investigate the clinical performance and physiological responses in a group of successful long-term wearers of conventional hydrogel lenses when refitted with DW SiH contact lenses. METHODS. Eighty-seven successful soft lens wearers (8.4 ± 4.7 years of prior lens wear) participated in this study. Bulbar and limbal hyperemia were subjectively graded and digitally photographed for subsequent masked objective evaluation. Subjective symptoms were scored using visual analog scales. In addition, refractive error, corneal curvature, and corneal thickness were measured. All subjects were refitted with Focus Night & Day (lotrafilcon A) SiH lenses; however, to reduce the potential for bias, they were informed that they were being randomly assigned to wear either low oxygen permeability (Dk) lenses or high Dk SiH lenses and were "masked" as to their lens assignment. Subjects returned after 1 week, 1 month, and 2 months of DW, at which time all gradings, photographs, and measurements were repeated. End-of-day subjective symptoms were also graded periodically during the study. RESULTS. Ninety-three percent of subjects were successfully refitted. Both objective and subjective evaluations showed that bulbar and limbal hyperemia decreased significantly in all quadrants during the study (p < 0.001), particularly for those subjects with greater baseline hyperemia (p < 0.001). Subjects reported a concurrent reduction in end-of-day dryness and improved end-of-day comfort compared with their habitual lenses (p < 0.001). No significant changes in refractive error, tarsal papillary response, corneal curvature, or corneal thickness were found during the study. CONCLUSIONS. Hyperemia in contact lens wearers may be attributed to a number of factors, including hypoxia. Refitting existing low Dk lens wearers with SiH lenses on a DW basis can result in a decrease in hyperemia, which may be significant for some subjects and also results in improvements in symptoms of dryness and discomfort. © 2006 American Academy of Optometry.

Moezzi,A. M., Fonn,D., Simpson,T. L. Overnight corneal swelling with silicone hydrogel contact lenses with high oxygen transmissibility Eye and Contact Lens 2006;32(6):277-280 [ Show Abstract ]

PURPOSE. To compare central corneal swelling after 8 hours of sleep in eyes wearing 2 different silicone hydrogel lenses with high oxygen transmissibility. METHODS. Twenty neophyte subjects were randomly assigned to wear a comfilcon A lens (CooperVision Inc) in one eye and a lotrafilcon A lens (CIBA Vision) in the contralateral eye for an 8-hour overnight period. The study was repeated with another 20 neophyte subjects wearing comfilcon A in one eye only and no lens in the contralateral control eye. Central corneal thickness was measured with optical pachometry before lens insertion, immediately after lens removal on waking, at 20 and 40 minutes, 1 hour, 2 hours and 3 hours. RESULTS. There was no significant difference between the amount of overnight central corneal swelling induced by the 2 lenses (4.1% ± 1.9% with comfilcon A vs. 4.0% ± 1.7% with lotrafilcon A; P>0.05). The swelling of the comfilcon A lens-wearing eyes was significantly higher than that found in the non-lens-wearing contralateral eyes (4.5% ± 2.1% vs. 3.0% ± 1.7%; P<0.05). CONCLUSIONS. The same amount of overnight corneal swelling was induced by the 2 study lenses. The higher overnight swelling observed with the comfilcon A lenses compared to the non-lens-wearing eyes is similar to that reported in the literature for studies using lotrafilcon A lenses. © 2006 Lippincott Williams & Wilkins, Inc.

Moezzi,A. M., Sin,S., Simpson,T. L. Novel pachometry calibration Optometry and Vision Science 2006;83(6):E366-E371 [ Show Abstract ]

PURPOSE: The purpose of this study was to develop a simple method for cross-calibrating instruments that measure corneal thickness. METHODS: Fourteen rigid lenses of different thicknesses were manufactured using a material with refractive index of 1.376. Center thickness of the lenses (CT) was measured using a computerized optical pachometer (OP), two optical coherence tomographers (OCTs), and a confocal microscope (CM). Accuracy of measurements was compared between the four instruments. RESULTS: Before calibrating the machines, there was a significant effect of the measurement device (p < 0.05). The differences between instruments were eliminated (p > 0.05) after applying calibration equations for each device. In addition, after each instrument was calibrated with lenses of 1.376 refractive index, there was no significant difference (p > 0.05) between measured values of lens center thickness by OP, each OCT, CM, and the physical center thickness of the lenses. CONCLUSIONS: Using calibration lenses with the same refractive index as the cornea (1.376) allows rapid and simple calibration of the pachometers so that corneal thickness measurements from different devices can be used interchangeably.

2004

Moezzi,A. M., Fonn,D., Simpson,T. L., Sorbara,L. Contact lens-induced corneal swelling and surface changes measured with the Orbscan II corneal topographer Optometry and Vision Science 2004;81(3):189-193 [ Show Abstract ]

Purpose. The purpose of this study was to measure central and topographical corneal swelling in response to contact lens wear and eye closure, to determine whether the swelling induced by soft and polymethyl methacrylate (PMMA) lenses is different, and to determine whether the anterior and/or posterior corneal shape alters with corneal swelling. Methods. An Orbscan II corneal topographer was used to measure corneal swelling and the shape of the anterior and posterior corneal surfaces of 16 neophytes before and after wearing soft and PMMA contact lenses with near-zero oxygen transmissibility. The lens-wearing eye was patched for 3 h. Results. The mean 15.1% ± 3.8% (±SD) central corneal swelling with soft lenses was significantly > 12.6% ± 4.1% with PMMA lenses. Topographical corneal swelling was significantly greater with soft vs. PMMA lenses. However, the difference between central and peripheral corneal swelling was much greater with PMMA lenses. With both lenses, the cornea swelled significantly more in the center than the periphery. The anterior best-fit sphere radius remained unchanged in response to soft lenses (0.00 ± 0.04 mm) and steepened slightly but significantly with PMMA lenses (-0.04. ± 0.05 mm). The posterior best-fit sphere radius flattened significantly with both lenses (0.12 ± 0.07 mm with soft and 0.14 ± 0.08 mm with PMMA lenses). Conclusions. Corneal swelling (greater centrally than peripherally) flattens the posterior surface of the cornea and is independent of lens type. Although the anterior best-fit sphere radius steepened with PMMA, the magnitude is probably clinically unimportant. Both lens types produced greater central vs. peripheral corneal swelling. However, the soft lens induced significantly greater overall swelling than PMMA. Because their oxygen transmission was the same, these results suggest that there is lateral diffusion of oxygen from the peripheral area of the cornea (that is not covered by the lens) toward the center.

Scientific Presentations

2024

Moezzi A, Moghadas M, Laachiri K, Lamrani M, Woods J, Jones L, Ngo W. Dry Eye Diagnostic Efficacy of Novel Ocular Thermography Metrics American Academy of Optometry Meeting, Indianapolis, Nov 8, 2024 [ Show Abstract ]

Purpose: This pilot study aimed to investigate the efficacy of novel ocular thermography metrics for screening and diagnosis of dry eye disease (DED).

Methods: This was a prospective study that enrolled 20 DED participants that were sex- and age-matched (12 female, 8 male, 33.3 ± 14.8 years) to 20 non-DED controls (12 female, 8 male, 33.6 ± 14.6 years). Participants were non-contact lens wearers, healthy, and free of ocular disease, except for DED in the DED group. During the screening visit (V1), OSDI (Ocular Surface Disease Index) score, Dry Eye Questionnaire-5 (DEQ5) score, non-invasive tear-break-up time (NITBUT), tear meniscus height (TMH), meibomian gland dysfunction (MG) score and corneal staining were obtained from both groups. DED group was defined as: OSDI score of ≥ 13 or DEQ-5 score of ≥ 6, and ≥ 1 of DED signs in at least one eye (corneal/conjunctival/lid margin staining, NITBUT < 5, Tear film osmolarity ≥ 308 mOsm/L). The next day (V2), a 30 second thermography recording of the ocular surface was conducted using an infrared recording camera (FLIR A655sc™), during which participants maintained natural blinking and constant straight-ahead gaze. Thermal cooling rate and thermal interblink interval (IBI) were derived from the recording.

Results: Thermal IBI was significantly lower in the DED group compared to the non-DED group (Mean ± SD) (1.89 ± 0.89 vs 2.54 ± 0.88; p=0.034). Thermal cooling rate (°C/sec) for 30 second measurement was significantly faster in the DED group than in the non-DED group (-0.12 ± 0.07 vs -0.08 ± 0.04; p=0.047). For clinical measurements, significant differences were noted between groups for the OSDI score, DEQ-5 score, NITBUT, MG score, corneal staining (all p<0.001) and TMH (p=0.011). Thermal IBI significantly correlated with DEQ5 score (r=-0.37; p=0.025) and OSDI score (r=-0.37; p=0.026). Thermal cooling rate correlated with DEQ5 score (r=-0.39; p=0.022) and OSDI score (r=-0.36; p=0.036). Area under the curve of the receiver operator characteristics (ROC) function was 0.70 for thermal cooling rate and thermal IBI. Thermal cooling rate (p=0.047) and TMH (p=0.044) were found as significant predictor variables for the dependent variable ‘DEQ5 score’ (linear mixed model). Thermal IBI (p=0.037) and MG score (p<0.001) were also found as significant predictor pair for ‘DEQ5 score'.

Conclusion: Thermal IBI and thermal cooling rate over 30 seconds of natural blinking were found as significant predictors of DED, suggesting the efficacy of these novel ocular thermography-derived metrics for DED screening.

2019

Guthrie S, Moezzi A, Varikooty J, Woods J, Jones L. A bilateral dispensing evaluation of two different toric lens geometries
BCLA Conference, Manchester, UK, 2019 [ Show Abstract ][ PDF ]

Purpose: To evaluate the subjective acceptance of two different types of prism ballast toric lens geometries, when worn on a daily wear modality over 1 month.
Methods: The study was a prospective, double-masked, bilateral, randomized, cross-over, 1-month wear, dispensing study where 45 astigmats wore two different soft toric lenses: comfilcon A toric which utilises a uniform horizontal iso-thickness design and samfilcon A toric which utilises a thin-edge design. Assessments were completed at 1-month. Ratings (0-10 scale) were competed at 2-weeks and 1-month.
Results: At 1-month, investigator-rated lens fit acceptance was high for both lens designs (3.65 vs 3.58, p=0.29), as was logMAR visual acuity for high contrast, high illumination (-0.12 vs -0.12, p=0.63) and low illumination (-0.10 vs -0.09, p=0.71). Subjective ratings for ‘overall visual quality’ were significantly higher for comfilcon A at 1-month (8.1 vs 7.4, p=0.04), but not different at 2-weeks (8.2 vs 7,6, p=0.05). ‘Vision stability’ ratings were significantly higher for comfilcon A at 2-weeks (8.2 vs 7.3, p=0.01) and 1-month (8.0 vs 7.2, p=0.03). ‘Overall comfort’ was rated significantly better with comfilcon A at 2-weeks (8.1 vs 7.4, p=0.04) and 1-month (8.1 vs 7.4, p=0.03). ‘End of day comfort’ ratings were similar after 1-month but significantly better with comfilcon A at 2-weeks (7.2 vs 6.5, p=0.03). ‘Overall satisfaction’ was statistically higher for comfilcon A after 2-weeks (8.0 vs 7.0, p<0.01) and 1-month (7.8 versus 7.0, p=0.02). Comfortable wearing time was not different at 2-weeks (9.2 vs 8.8, p=0.12), but was significantly longer with comfilcon A at 1-month (8.9h vs 8.0h, p=0.03).
Conclusions: Although both comfilcon A and samfilcon A use a prism ballast stabilisation principle and both provide excellent acuity and lens fit results, comfilcon A provided better subjective results for vision, vision stability, comfort, comfortable wear time and overall satisfaction.

Guthrie S, Woods J, Moezzi A, Varikooty J, Jones L. Comparing in-office evaluations to subjective evaluations for two toric lenses American Academy of Optometry, Orlando, 2019 [ Show Abstract ][ PDF ]

Purpose: To evaluate the performance of two monthly replacement silicone hydrogel toric lenses, comfilcon A toric and samfilcon A toric, using in-office assessments and subjective evaluations after 1 month.

Methods: A prospective, double-masked, bilateral, cross-over, dispensing study was conducted, where 45 subjects wore each lens type in a reusable, daily wear modality for 1 month, in a randomised order. Both in-office and subjective evaluations (0 [worst]-10 [best] scale) were completed at 1-month.

Results: Comfilcon A and samfilcon A toric lenses both performed well and similarly in all aspects of investigator lens evaluation. At 1-month, there was no significant difference for ‘fit acceptance’ grades (3.65 vs 3.58, p=0.29), ‘overall lens stability’ (3.56 vs 3.42, p=0.09) or for measures of logMAR high contrast acuity under ‘high illumination’ (-0.12 vs -0.12, p=0.63) or ‘low illumination’ (-0.10 vs -0.09, p=0.71). However, subject evaluations did show some significant differences related to comfort and vision. At 1-month comfilcon A toric lenses were rated significantly better for ‘overall comfort’ (8.1 vs 7.4, p=0.03). The difference in the 1-month ratings for ‘end of day comfort’ was not statistically significant (7.1 vs 6.7, p=0.15), however the ‘comfortable wear time’ was significantly longer for comfilcon A toric (8.9h vs 8.0h, p=0.03). For vision, comfilcon A toric was rated significantly better for ‘overall vision quality’ (8.1 vs 7.4, p=0.04) and ‘vision stability’ (8.0 vs 7.2, p=0.03). Subjects were asked to rate their ‘overall satisfaction’ and comfilcon A toric was rated significantly higher (7.8 versus 7.0, p=0.02). Subjects were also asked if they had a lens preference. Of those with a preference, significantly more subjects preferred the comfilcon A toric lens in terms of comfort (32 vs 10, p<0.01), dryness (28 vs 10, p=0.01) and overall (31 vs 13, p=0.01).

Conclusions: Although both comfilcon A and samfilcon A toric lenses both provided similar, high-level results for lens fit, stability and acuity, comfilcon A toric was rated statistically significantly higher in the subjective evaluations, specifically for comfort, vision, vision stability, overall satisfaction and comfortable wear time. These results illustrate that the patient experience cannot always be predicted from in-office evaluations.

Yang M, Moezzi A, Woods J, Jones L. Comparing Strip Meniscometry to Tear Meniscus Height & Schirmer Test American Academy of Optometry, Orlando, 2019 [ Show Abstract ][ PDF ]

Purpose: Evaluation of tear volume is an important parameter for investigating aqueous deficient dry eye disease (DED). Historically, this has been achieved using Schirmer (SCH) strips or non-invasively using estimation of tear meniscus height (TMH). A method using strip meniscometry (SM) (SMTube, Shirakawa Factory, Tokyo, Japan) has recently been developed as a fast (5-second) in-office diagnostic test. The purpose of this study was to determine how tear volume assessed by SM compared to TMH and SCH in a mixed cohort of subjects with and without DED.

Methods: Both eyes of 27 participants (7 males; 20 females) aged between 21 and 64 (mean 40.7 years) underwent all measurements. TMH and non-invasive tear breakup time (NITBUT) were assessed using the Keratograph5M (Oculus, Germany). Subjects completed the ocular surface disease index (OSDI). SM was undertaken, and after a 1 hour delay, SCH (without anesthetic) was measured over five minutes. Subjective preference between SM and SCH was also collected. The correlation between SM and NITBUT, TMH and SCH were analysed.

Results: Only right eye data is presented. The mean (±SD) scores were: SM 5.6 (±3.2) mm; NITBUT 8.82 (±5.35) seconds; TMH 0.23 (±0.07) mm; SCH 22.2 (±10.1) mm. Mean OSDI was 13.1 (±9.3). The linear correlations (Pearson r) with SM were all low: NITBUT (0.479), TMH (0.006), SCH (0.301) and OSDI (0.075). 100% of participants preferred SM to SCH, citing the reasons for their preference as better comfort and shorter test time.

Conclusion: Strip meniscometry (SM) is a more rapid test compared to Schirmer test, and was found to be significantly more comfortable by the participants. However, given the low correlation with standard tear film evaluation tests its ability to discriminate between patients with and without DED requires further evaluation.

2018

Woods J, Moezzi A, Varikooty J, Jones L. Comparison of lens orientation stability of two daily disposable silicone hydrogel toric lenses Contact Lens & Anterior Eye 2018;41, Supp 1:S93

2017

Moezzi A, Varikooty J, Luensmann D, Schulze M, Ng AY, Karkkainen T, Xu J, Jones L. Evaluation of Clinical Success with etafilcon A multifocal daily disposable lenses Optom Vis Sci 2017;94: E-Abstract 175341

2016

Moezzi A, Fonn D, Hutchings N, Simpson T. Mixed model analysis of corneal deswelling following overnight wear of silicone hydrogel lenses Invest Ophthalmol Vis Sci 2016;57: E-abstract 1491 [ PDF ]

Moezzi A, Varikooty J, Luensmann D, Ng A, Schulze M, Karkkainen T, Xu J, Jones L. Open-eye clinical performance of etafilcon a multifocal daily disposable hydrogel contact lenses compared to habitual silicone hydrogel lens wear Optom Vis Sci 2016;93: E-abstract 165259 [ PDF ]

2014

Cox S, Berntsen D, Chatterjee N, Hickson-Curran S, Jones L, Moezzi A, Morgan P, Nichols J. Eyelid margin characteristics associated with a large cohort of soft contact lens wearers Optom Vis Sci 2014;91: E-abstract 140080

Moezzi A, Varikooty J, Schulze M, Ngo W, Lorenz K, Boree M. Open-eye corneal swelling with etafilcon A daily disposable hydrogel contact lenses compared to no lens wear BCLA Clinical Conference and Exhibition, 2014 [ PDF ]

Moezzi A, Varikooty J, Schulze M, Ngo W, Lorenz K, Jones L. Open Eye Corneal Swelling with 1-DAY ACUVUE® DEFINE™ and 1-DAY ACUVUE® DEFINE™ with Lacreon® compared to 1-DAY ACUVUE® MOIST® Invest Ophthalmol Vis Sci 2014;55: E-abstract 4672 [ PDF ]

Stahl U, Luensmann D, Lemp J, Moezzi A, Schulze M, Varikooty, Dumbleton K, Jones L. Determination of higher order aberrations with two silicone hydrogel toric lenses Optom Vis Sci 2014;91: E-abstract 145188 [ PDF ]

2013

Moezzi A, Richter D, Varikooty J, Simpson T. A Novel Method for removing inter-observer Bias in Optical Pachometry 8th Canadian Optometry Schools Research Conference (COSRC), 2013

2012

Dumbleton K, Woods C, Moezzi A, Fonn D, Jones L. The influence of masked lens replacement on subjective comfort and vision with aging soft contact lenses Contact Lens & Anterior Eye 2012;35, S1:e38

Dumbleton K, Woods CA, Woods J, Moezzi A, Fonn D, Jones L. An Investigation Into The Role Of Masked Lens Replacement On Subjective Comfort And Vision With Aging Soft Contact Lenses Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 4722

Fonn D, Holden B, Moezzi A, Lazon de la Jara P, La Hood D, Richter D. Overnight Corneal Swelling (ONCS) of the Contralateral Non-Lens Wearing Eye is affected by the amount of ONCS in the Lens Wearing Eye American Academy of Optometry, 2012

Holden B, Fonn D, La Hood D, Moezzi A, Richter D, Lazon de la Jara P. Revised Estimate of the Oxygen Transmissibility Needed to produce Same Level of Overnight Corneal Swelling as that which occurs when No Lens is worn American Academy of Optometry, 2012

2011

Anderson T, Moezzi A, Varikooty J, Jones L, Woods C, Fonn D. A novel method for measuring contact lens movement and centration using a high speed camera and computer vision Optom Vis Sci 2011;88:E-abstract 115439

Moezzi A, Situ P, Luensmann D, Fonn D, Woods C, McNally J, Jones L. Does comfort with aging silicone hydrogel lenses relate to changes in lens fit and conjunctival staining? Optom Vis Sci 2011;88:E-abstract 115708

2010

Fonn D, Moezzi A, Richter D, Woods CA. Can Overnight Lens Induced Corneal Swelling Be Minimised to Equal No Lens Wear Regardless of Oxygen Transmissibillity? Optom Vis Sci 2010;87:E-Abstract 100318

Fonn D, Woods C, Richter D, Moezzi A. Critical Oxygen Transmissiblity to Avoid Overnight Lens Induces Corneal Swelling Contact Lens & Anterior Eye 2010;33, 6:267

2009

Fonn D, Moezzi A, Varikooty J. Distribution of overnight corneal swelling across subjects with 4 different silicone hydrogel lenses Invest Ophthalmol Vis Sci 2009;50:E-abstract 5658

Fonn D, Moezzi A, Varikooty J. Average and individual overnight central corneal swelling with four different silicone hydrogel lenses Contact Lens & Anterior Eye 2009;32, 5:229

Moezzi A, Fonn D, Varikooty J, Richter D. Distribution of overnight central corneal swelling with high powered silicone hydrogel lenses Optom Vis Sci 2009;86:E-abstract 90898

2008

Fonn D, Moezzi A, Varikooty J, Simpson TL. The effect of oxygen transmissibility on central and peripheral overnight corneal swelling with four different silicone hydrogel lenses Optom Vis Sci 2008;85: E-abstract 85077

Moezzi A, Fonn D, Varikooty J, Simpson TL. The effect of lens power on central and peripheral overnight corneal swelling with four different silicone hydrogel lenses Optom Vis Sci 2008;85: E-abstract 85076

2007

Dumbleton K, Jones L, Woods CA, Feng Y, Moezzi A and Fonn D. Clinical performance of a hydrogen peroxide care regimen with silicone hydrogel lenses Contact Lens & Anterior Eye 2007;30, 5:301

2006

Dumbleton K, Jones L, Woods C, Feng Y, Moezzi A, Fonn D. Clinical performance of a hydrogen peroxide care regimen with silicone hydrogel lenses Optom Vis Sci 2006;83: E-Abstract 060069

Dumbleton K, Moezzi A, Fonn D, Simpson T. Comparision of overnight corneal swelling induced by lotrafilcon b toric versus alphafilcon a toric lenses Contact Lens & Anterior Eye 2006;29, 4:193

Dumbleton K, Woods C, Jones L, Feng Y, Moezzi A, Fonn D. Comfort and adaptation to silicone hydrogel lenses for daily wear Optom Vis Sci 2006;83: E-Abstract 060066

Keir N, Moezzi A, Fonn D, Varikooty J, Simpson T. Overnight corneal swelling of silicone hydrogel contact lenses with high oxygen transmissibility Contact Lens & Anterior Eye 2006;29, 4:196

Moezzi A, Fonn D, Simpson T. Comparison of overnight corneal swelling induced by prototype lotrafilcon a toric versus balafilcon a toric Optom Vis Sci 2006;83: E-Abstract 060095

2005

Moezzi A, Fonn D, Varikooty J, Simpson T. Overnight corneal swelling of silicone hydrogel contact lenses with high oxygen transmissibility Optom Vis Sci 2005;82: E-abstract 050083

2004

Dumbleton K, Keir N, Moezzi A, Jones L, Fonn D. Redness, dryness and comfort following refitting long-term low Dk lens wearers with silicone hydrogel lenses Optom Vis Sci 2004;81, 12s:31

Dumbleton K, MacDougall N, Jones L, Moezzi A, Fonn D, McNally J. Changes in hyperemia subsequent to refitting long-term low Dk wearers with silicone hydrogel lenses on a daily wear basis Contact Lens & Anterior Eye 2004;27, 2:102

Fonn D, Moezzi A, Simpson TL, Situ P. Confirmation of a yoked corneal swelling response between the test and contralateral control eye Optom Vis Sci 2004;81, 12s:30

Situ P, Moezzi A, Fonn D, Simpson TL. Comparing perilimbal hyperemia after overnight wear of O2 Optix and Acuvue 2 contact lenses Optom Vis Sci 2004;81, 12s:59

2001

Moezzi A, Fonn D, Sorbara L, Simpson T. Effects of contact lens induced swelling on anterior and posterior corneal surfaces Optom Vis Sci 2001;78, 12s:303

Professional Publications

2024

Moezzi A, Ruston D. Truth or myth: Daily disposable hydrogel wearers should be refitted into DD silicone hydrogel lenses? Optician: https://www.opticianonline.net/content/features/truth-or-myth-daily-disposable-hydrogel-wearers-should-be-refitted-into-dd-silicone-hydrogel-lenses/ 2024, April 5:

2021

Moezzi A. CLEAR report summary: Effect of Contact Lens Materials and Designs on the Anatomy and Physiology of the Eye https://contactlensupdate.com/2021/06/15/effect-of-contact-lens-materials-and-designs-on-the-anatomy-and-physiology-of-the-eye/ 2021;60

2017

Moezzi A. Summary: Pain and sensation report ContactLensUpdate.com 2017

2004

Moezzi A, Fonn D. Corneal thickness measurement Contact Lens Spectrum 2004

Books

2022

Jones L, Stahl U, Guthrie S, Yang M, Moezzi A, Thom M. Contact Lens Compendium: Contact Lenses & Solutions Available in America. Vol 3 2022.

2021

Jones L, Stahl U, Guthrie S, Yang M, Moezzi A, Thom M. Contact Lens Compendium: Contact Lenses & Solutions Available in America. Vol 2 2021.

Jones L, Stahl U, Guthrie S, Yang M, Moezzi A, Thom M. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 47 2021.