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Peer-reviewed articles


Schulze,M., Ng,A. Y., Yang,M., Panjwani,F., Srinivasan,S., Jones,L., Senchyna,M. Bulbar redness and dry eye disease: comparison of a validated subjective grading scale and an objective automated method Optometry & Vision Science 2021;98(2):113-120 [ Show Abstract ]

In this study, assessments of conjunctival redness were performed to evaluate whether patients with or without dry eye disease (DED) could be discriminated based on this measure. Our findings suggest that subjectively grading redness by quadrant, as opposed to automated en face measurements, may be more suitable for this purpose.

This study aimed to quantify bulbar redness using the validated bulbar redness (VBR) grading scale and an automated objective method (Oculus Keratograph 5M; K5M) in participants with DED and non-DED controls.

Participants with DED (Ocular Surface Disease Index score ≥20 and Oxford scale corneal staining ≥2) and controls (Ocular Surface Disease Index score ≤10 and corneal staining ≤1) attended two study visits. In part 1A of visit 1, baseline bulbar redness was graded with the VBR scale in each conjunctival quadrant of both eyes, followed by automated measurements of temporal and nasal redness with the K5M. This was immediately followed by part 1B, during which a topical vasoconstrictor was instilled into both eyes. Redness assessments were repeated 5 and 30 minutes after instillation with both instruments. Participants returned 14 days later for visit 2, where the same assessments as for visit 1A were repeated.

Seventy-four participants (50 DED and 24 controls) completed the study. There were statistically significant differences in redness between the DED and control groups when assessed with the VBR scale (14/16 comparisons; all, P < .05), whereas no significant differences in K5M-derived redness between the DED and non-DED groups were found at any location or time point. Both subjective and objective instruments detected statistically significant reductions in redness 5 and 30 minutes after instillation of the vasoconstrictor (all, P < .01).

Although both subjective and objective instruments were sensitive to detecting changes in redness induced by vasoconstriction, statistically significant differences in redness between DED and control groups were only found using the VBR scale.

Yee,A., Walsh,K., Schulze,M., Jones,L The impact of patient behaviour and care system compliance on reusable soft contact lens complications Contact Lens Anterior Eye 2021;Online ahead of print [ Show Abstract ]

Reusable soft daily wear contact lenses (CLs) remain popular and were fit to just over half of all wearers in the most recent international CL prescribing survey. Unlike daily disposable CLs, reusables require cleaning and disinfecting after every use, along with storage in a CL case. These additional requirements add a number of steps to the daily wear and care routine, increasing the opportunities for CL wearers to exhibit non-compliant behaviour. The impact of non-compliance ranges from poor lens comfort through to potentially sight- threatening infective keratitis. The coronavirus pandemic has refocused the profession on the importance of hand hygiene in particular, and the need for promoting safe CL wear in general. This review summarises typical non-compliant behaviour related to reusable CLs, and examines strategies and opportunities to better support wearers. Patient education has a central role in encouraging compliant behaviour, although patient recall of information is low, and personal belief systems may result in continuation of non-compliant behaviour despite awareness of the risks. CL care solutions are required for the daily disinfection of lenses, however misuse of multipurpose solutions (MPS) and hydrogen peroxide (H2O2)-based care systems can challenge their ability to be fully efficacious. Standard efficacy testing is reviewed, with consideration of how well current protocols model real-world use of CL solutions. Although some recommendations are in place for the inclusion of additional variables such as lens cases, CL materials, organic soil and efficacy against Acanthamoeba, opportunity still exists to reevaluate global standards to ensure consistency of testing in all markets. Finally, potential future innovations are discussed which may further support increased safety in reusable lens wear through novel antimicrobial additions to both CL materials and cases


Shows,A., Redfern,R. L., Sickenberger,W., Fogt,J. S., Schulze,M., Lievens,C., Szcottka-Flynn,L., Schwarz,S., Tichenor,A. A., Marx,S., Lemp-Hull,J. M. Lipid Analysis on Block Copolymer–containing Packaging Solution and Lens Care Regimens: A Randomized Clinical Trial Optometry & Vision Science 2020;97(8):565-572 [ Show Abstract ]

SIGNIFICANCE: Lotrafilcon B lenses packaged in and cared for with block copolymer–containing (polyoxyethylenepolyoxybutylene; EOBO) lens care solutions resulted in lower cholesterol extraction than each of the habitual silicone hydrogel lens/multipurpose solution (MPS) regimens tested.

PURPOSE: This study aimed to compare the extracted cholesterol of lotrafilcon B lenses packaged in and cared for with EOBO-containing lens care solutions with the extracted cholesterol of habitual silicone hydrogel lenses cared for with MPS not containing EOBO.

METHODS: In this prospective, randomized, observer-masked parallel study, habitual wearers of senofilcon C, senofilcon A, comfilcon A, and samfilcon A contact lenses using a non-EOBO MPS were randomized 1:1 to lotrafilcon B lenses packaged in and cared for with EOBO-containing solutions or to their habitual lenses and MPS. Subjects randomized to lotrafilcon B were further randomized to one of two EOBO-containing lens care solutions, OPTI-FREE PUREMOIST or CLEAR CARE PLUS with HydraGlyde (Alcon Laboratories, Inc., Fort Worth, TX). A subset of right eye lenses was collected after wear, and total cholesterol was extracted and measured using a fluorometric enzymatic assay.

RESULTS: Of 143 lenses analyzed, 95 were from subjects randomized to their habitual lenses/MPS and 48 to lotrafilcon B + EOBO lenses plus CLEAR CARE PLUS with HydraGlyde or OPTI-FREE PUREMOIST. The mean amounts of cholesterol extracted from lotrafilcon B + EOBO lenses cared for with CLEAR CARE PLUS with HydraGlyde (0.28 ± 0.18 μ g/lens) and OPTI-FREE PUREMOIST (0.28 ± 0.48 μ g/lens) were significantly lower than those extracted from senofilcon C (4.18 ± 3.25 μ g/lens), senofilcon A (2.19 ± 2.69 μ g/lens), comfilcon A (2.17 ± 1.47 μ g/lens), and samfilcon A (2.07 ± 1.48 μ g/lens) lenses used with MPS (P < .0001 each).

CONCLUSIONS: Cholesterol sorption was significantly lower in wearers of lotrafilcon B lenses cared for with polyoxyethylene-polyoxybutylene–containing lens care solutions than in users of habitual silicone hydrogel lenses cared for with non–polyoxyethylene-polyoxybutylene MPS.

Yeu,E., Silverstein,S., Guillon,M., Schulze,M., Galaretta,D., Srinivasan,S., Manoj,V. Efficacy and Safety of Phospholipid Nanoemulsion-Based Ocular Lubricant for the Management of Various Subtypes of Dry Eye Disease: A Phase IV, Multicenter Trial Clinical Ophthalmology 2020;14:2561-2570 [ Show Abstract ]

Purpose: To evaluate the clinical efficacy and safety of propylene glycol/hydroxypropylguar (PG-HPG)-based nanoemulsion (Systane ® Complete) lubricant eye drops in participants with dry eye disease (DED).

Participants and Methods: In this phase IV, open-label, single-arm, interventional, multicenter study, adult participants with DED – subtyped into aqueous deficient, evaporative, and mixed dry eye – were instructed to instill one drop of PG-HPG in each eye twice a day for 28 days. Endpoints included change from baseline in tear film break-up time (TFBUT) (primary) and ocular discomfort visual analog scale (VAS) score at Day 14 and TFBUT at Day 28 (secondary). Safety was assessed throughout the study. Data were analyzed for overall patient cohort and by DED subtypes. Results: A total of 134 participants received treatment (mean age: 56.6 years; female: 75.4%). At Day 14, the mean (standard deviation [SD]) TFBUT increased from 2.6 (1.00) seconds at baseline to 4.2 (2.92) seconds (mean change: 1.5 [2.80] seconds); median change was 0.8 seconds (95% CI: 0.52, 1.19) for the overall cohort; the change was maintained at Day 28 (mean change: 1.4 (2.80) seconds, median change: 0.8 seconds (95% CI: 0.49, 1.17). Subgroup analysis showed a mean change (SD) from baseline in TFBUT of 1.1 (2.41) seconds for aqueous deficient, 2.4 (3.17) seconds for evaporative, and 1.2 (2.63) seconds for mixed dry eye at Day 14, respectively. The ocular discomfort VAS score improved (decreased) from baseline at Day 14 (mean [SD] change: −17.3 [24.80]) for the overall cohort, −22.0 [21.73] for aqueous deficient, −17.6 [24.17] for evaporative and −13.1 [27.49] for mixed dry eye subgroups). Adverse events (AEs) were reported in 9 (6.7%) participants. No serious AEs were reported during the study.

Conclusion: Our study findings demonstrated that PG-HPG-based nanoemulsion lubricant eye drops were effective and well tolerated in participants with DED and all of its subtypes. Keywords: aqueous deficient dry eye, dry eye disease, evaporative dry eye, propylene glycol/hydroxypropyl guar-nanoemulsion ocular lubricant, mixed dry eye


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.


Berntsen,D. A., Hickson-Curran,S. B., Jones,L. W., Mathew,J. H., Maldonado-Codina,C., Morgan,P. B., Schulze,M. M., Nichols,J. J. Subjective comfort and physiology with modern contact lens care products Optometry and Vision Science 2016;93(8):809-819 [ Show Abstract ]

Purpose. To compare subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to that of a peroxide-based system with three different soft contact lens materials. Methods. Habitual soft contact lens wearers (n = 236) were enrolled at three sites and completed a washout period with no contact lens solution for =4 days. Subjects were randomly assigned to one of three lens types: etafilcon A, galyfilcon A, or senofilcon A. A new lens of the assigned type was worn for 10 to 14 days each while using one of four care solutions, in random order (A - polyaminopropyl biguanide + polyquaternium, B - POLYQUAD + Aldox, C - alexidine + polyquaternium-1, and D - hydrogen peroxide) with a washout period (=4 days) between each solution. After each care solution, biomicroscopy was performed and subjective comfort was assessed using the Contact Lens User Experience (CLUE) questionnaire and other instruments including comfortable wear time (CWT). Linear mixed models were used for analysis. Comfort and biomicroscopy signs with each MPS were compared to that of the peroxide solution. Results. Subjective CLUE Comfort score across all lens types with each MPS was not significantly different than with the peroxide solution (p = 0.98). There were no differences in CWT between each MPS and the peroxide solution for any lens type (range of differences: -0.8 to 0.8 h; all p = 0.13). Six MPS/material combinations had no clinically meaningful change in corneal staining versus peroxide (<0.5 units); three combinations could increase staining by up to 0.57 units. Staining was

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.

Schulze,M. -M, Srinivasan,S., Hickson-Curran,S. B., Berntsen,D. A., Howarth,G. F., Toubouti,Y., Morgan,P., Nichols,J. J., Jones,L. W. Lid wiper epitheliopathy in soft contact lens wearers Optometry and Vision Science 2016;93(8):943-954 [ Show Abstract ]

Purpose. To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presentation and after using various SCL and solution combinations. Methods. LWE was assessed in 253 habitual SCL wearers who attended a screening visit at one of three study sites. LWE was assessed using lissamine green and sodium fluorescein dyes (Korb scale); a final LWE grade was calculated as the averaged LWE grade of the two dyes. Eligible habitual wearers continued into the four study periods, during which they wore one of three SCL types (etafilcon A, galyfilcon A, or senofilcon A) while using each of four care solutions for 10 to 14 days in randomized order. Statistical analyses were performed using linear mixed models, testing for differences in LWE for subject characteristics and between three multipurpose (MPS) test solutions (BioTrue, OPTI-FREE PureMoist, RevitaLens OcuTec) compared to a hydrogen peroxide (Clear Care) control solution. Results. LWE was present in 85% of habitual SCL wearers. LWE was not different for age (p = 0.28), sex (p = 0.99), race (p = 0.34), and comfort (p = 0.38) and not correlated with refractive error (r = 0.07). LWE was lower in habitual senofilcon A wearers (least-squares (LS) mean ± SE = 0.82 ± 0.19) compared to wearers of lotrafilcon B (1.34 ± 0.20; p < 0.02), comfilcon A (1.41 ± 0.21; p < 0.01), and other (1.18 ± 0.16; p < 0.03). Two hundred three participants completed all four study solutions with their assigned lens type; LWE was not different between the MPSs compared to the peroxide control solution across lens materials, except for less LWE for BioTrue (0.88 ± 0.17) versus Clear Care for participants wearing galyfilcon A (1.11 ± 0.18; p < 0.01). Conclusions. On initial presentation, LWE was present in 85% of habitual wearers and found to be independent of age, sex, race, comfort, and refractive error but dependent on habitual SCL type. There were no clinically meaningful differences in LWE between the MPSs and hydrogen peroxide solution for the three lens types studied. © Copyright 2016 American Academy of Optometry.


Varikooty,J., Schulze,M. M., Dumbleton,K., Keir,N., Woods,C. A., Fonn,D., Jones,L. W. Clinical performance of three silicone hydrogel daily disposable lenses Optometry and Vision Science 2015;92(3):301-311 [ Show Abstract ]

Purpose. To determine the clinical performance of DAILIES TOTAL1 (DT1), Clariti 1Day (C1D), and 1-DAY ACUVUE TruEye (AVTE) silicone hydrogel daily disposable contact lenses (SiHy DDCLs). Methods. Eligible participants, subdivided into asymptomatic and symptomatic groups, wore each SiHy DDCLs for three consecutive days. Each participant attended three visits (on day 1 at 0 hours; on days 1 and 3 after 8 hours ofwear) per lens type. The order of lens wear was randomized, with at least 1 day washout between lenses. Lens-related performance was evaluated by assessing lens surface deposits, wettability, pre-lens noninvasive tear breakup time, lens movement, and centration; ocular response assessments included conjunctival redness, corneal staining, and conjunctival staining and indentation. Results. Fifty-one asymptomatic and 53 symptomatic participantscompleted the study. For all visits, themeannoninvasive tear breakup timewas about 1 second longer withDT1 than withC1DandAVTE (p < 0.01).Overall, thewettability of all three lenses was good; however, DT1 was graded marginally better than the other lenses (both p < 0.01). On day 3, eyes wearing AVTE had significantly more dehydration-induced corneal staining compared with DT1 (AVTE, 24%; DT1, 11%; p < 0.01). After 8 hours, conjunctival staining was different between lenses (greatest with C1D and least with DT1; all p < 0.01). Conjunctival indentation was more prevalent with the C1D lenses (n = 70) compared with DT1 (n = 1; p < 0.01) and AVTE (n = 11; p < 0.01). Therewere no differences between asymptomatic and symptomatic lenswearers for any of the clinical parameters (all p 9 0.05). Conclusions. Each of the three SiHy DDCLs performed well. Noninvasive tear breakup time was longest and wettability was greater with DT1. C1D had the most conjunctival staining conjunctival indentation. There was no difference between asymptomatic and symptomatic wearers with regard to ocular response and contact lensYrelated parameters. These results suggest that SiHy DDCLs may be an excellent contact lens modality for the symptomatic patient.


Ngo,W., Srinivasan,S., Schulze,M., Jones,L. Repeatability of grading meibomian gland dropout using two infrared systems Optometry and Vision Science 2014;91(6):658-667 [ Show Abstract ]

PURPOSE: To determine the interobserver and intraobserver repeatability in using the OCULUS Keratograph 4 (K4) and 5M (K5M) to grade meibomian gland (MG) dropout using meibography grading scales. METHODS: The inferior and superior eyelids of 40 participants (35 women, 5 men; mean age = 32 years) were imaged three times each on both instruments. The images were split into one training and two study sets; the latter were graded (four-point meibography scale) by two observers on two separate occasions (24 hours apart) to determine repeatability. Semiobjective quantification of percentage MG dropout was conducted using ImageJ on K4 and K5M images. A finer seven-point meibography scale was used to grade a separate set of K5M images. RESULTS: For the four-point scale, interobserver mean difference (MD) (±SD) was 0.08 (±0.55) on day 1 and 0.13 (±0.50) on day 2, and the concordance correlation coefficient (CCC) was 0.79 and 0.81 on days 1 and 2, respectively. Intraobserver MD (±SD) was 0.04 (±0.54), CCC = 0.79 for observer 1; intraobserver MD (±SD) was -0.09 (±0.60), CCC = 0.74 for observer 2. For the seven-point scale, interobserver MD (±SD) was 0.05 (±0.45), CCC = 0.89 on day 1, and interobserver MD (±SD) was 0.01 (±0.41), CCC = 0.91 on day 2. Intraobserver MD (±SD) was -0.10 (±0.35), CCC = 0.93 for observer 1, and intraobserver MD (±SD) was -0.06 (±0.30), CCC = 0.95 for observer 2. Percentage dropout measured between the K4 and K5M images showed lack of agreement, with 21.8% coefficient of repeatability. There was no significant correlation (r 0.05) between meibography score and clinical signs (corneal staining, gland expressibility, telangiectasia, vascularity, lash loss); however, there was a high correlation (r = 0.77; p < 0.05) between meibography score with percentage dropout. CONCLUSIONS: Observers graded from -1 to +1 grade units between and within themselves for a four-point scale, 95% of the time. Although the interobserver and intraobserver repeatability of the K4 and K5M were very similar, a high rate of disagreement in percentage dropout between K4 and K5M images suggests that the two instruments cannot be interchanged. Meibomian gland dropout scores did not correlate significantly with clinical signs. Using a finer scale may be beneficial for detecting change.


Schulze,M. M., Hutchings,N., Simpson,T. L. Grading bulbar redness using cross-calibrated clinical grading scales Investigative Ophthalmology and Visual Science 2011;52(8):5812-5817 [ Show Abstract ]

Purpose. To determine the between-scale agreement of grading estimates obtained with cross-calibrated McMonnies/Chapman- Davies (MC-D), Institute for Eye Research (IER), Efron, and Validated Bulbar Redness (VBR) grading scales. Methods. Modified reference images of each grading scale were positioned on a desk according to their perceived redness (within a 0 to 100 range) as determined in a previous psychophysical scaling experiment. Ten observers were asked to represent perceived bulbar redness of 16 sample images by placing them, one at a time, relative to the reference images of each scale. Only 0 and 100 were marked on the scale, but not the numerical position of the reference images. Perceived redness was taken as the measured position of the placed image from 0 and was averaged across observers. Results. Overall, perceived redness depended on the sample image and the reference scale used (repeated measures ANOVA; P = 0.0008); six sample images had a perceived redness that was significantly different between at least two of the scales. Between-scale correlation coefficients of concordance ranged from 0.93 (IER vs. Efron) to 0.98 (VBR vs. Efron). Between-scale coefficients of repeatability ranged from five units (IER vs. VBR) to eight units (IER vs. Efron) of the 0 to 100 range. Conclusions. The use of cross-calibrated reference grades for bulbar redness grading scales allows comparison of grading estimates obtained with different scales. Perceived redness is dependent on the dynamic range of the reference images of the scale, with redness estimates generally being found to be higher for scales with a shorter dynamic range. © 2011 The Association for Research in Vision and Ophthalmology, Inc.


Schulze,M. M., Hutchings,N., Simpson,T. L. The conversion of bulbar redness grades using psychophysical scaling Optometry and Vision Science 2010;87(3):159-167


Schulze,M. M., Hutchings,N., Simpson,T. L. The perceived bulbar redness of clinical grading scales Optometry and Vision Science 2009;86(11):E1250-E1258 [ Show Abstract ]

Purpose. To use a psychophysical scaling method to estimate the perceived redness of reference images of the McMonnies and Chapman-Davies (six reference levels), Institute for Eye Research (four), Efron (five), and Validated Bulbar Redness (five) bulbar redness grading scales. Methods. Regions of interest were cropped out of the grading scale reference images; three separate image sets (color, grayscale, and binarized) were created for each scale, combining to a total of 20 images per image set. Ten naïve observers were asked to arrange printed copies of the 20 images per image set across a distance of 1.5 m on a flat surface, so that separation reflected their perception of bulbar redness; only start and end point of this range were indicated. The position of each image was averaged across observers to represent the perceived redness for this image, within the 0 to 100 range. Subjective data were compared with physical attributes (chromaticity and spatial metrics) of redness. Results. For each image set, perceived redness of the reference images within each scale was ordered as expected, but not all consecutive within-scale levels were rated as having different redness. Perceived redness of the reference images varied between scales, with different ranges of severity being covered by the images. Perception of redness severity depended on the image set (repeated-measures analysis of variance; all p ≤ 0.0002). The perceived redness was strongly associated with the physical attributes of the reference images. Conclusions. Subjective estimates of redness are based on a combination of chromaticity and vessel-based components. Psychophysical scaling of perceived redness lends itself to being used to cross-calibrate these four clinical scales. © 2009 American Academy of Optometry.


Schulze,M. M., Hutchings,N., Simpson,T. L. The use of fractal analysis and photometry to estimate the accuracy of bulbar redness grading scales Investigative Ophthalmology and Visual Science 2008;49(4):1398-1406 [ Show Abstract ]

Purpose. To use physical attributes of redness to determine the accuracy of four bulbar redness grading scales, and to cross- calibrate the scales based on these physical measures. Methods. Two image-processing metrics, fractal dimension (D) and percentage of pixel coverage (% PC), as well as photometric chromaticity were selected as physical measures, to describe and compare grades of bulbar redness among the McMonnies/Chapman-Davies scale, the Efron Scale, the Institute for Eye Research scale, and a validated scale developed at the Centre for Contact Lens Research. Two sets of images were prepared by using image processing: The first included multiple segments covering the largest possible region of interest (ROI) within the bulbar conjunctiva in the original images; the second contained modified scale images that were matched in size and resolution across scales, and a single, equally-sized ROI. To measure photometric chromaticity, the original scale images were displayed on a computer monitor, and multiple conjunctival segments were analyzed. Pearson correlation coefficients between each set of image metrics and the reference image grades were calculated to determine the accuracy of the scales. Results. Correlations were high between reference image grades and all sets of objective metrics (all Pearson's r ≥ 0.88, P ≤ 0.05); each physical attribute pointed to a different scale as being most accurate. Independent of the physical attribute used, there were wide discrepancies between scale grades, with almost no overlap when cross-calibrating and comparing the scales. Conclusions. Despite the generally strong linear associations between the physical characteristics of reference images in each scale, the scales themselves are not inherently accurate and are too different to allow for cross-calibration. Copyright © Association for Research in Vision and Ophthalmology.


Schulze,M. M., Jones,D. A., Simpson,T. L. The development of validated bulbar redness grading scales Optometry and Vision Science 2007;84(10):976-983 [ Show Abstract ]

PURPOSE: To develop a perceptually and physically based bulbar redness grading scale. METHODS: Digital conjunctival hyperemia photographs were taken using a photo-slit lamp at controlled exposures. Nine participants arranged 25 images on a tabletop over a range of 1.5 m, using separation to represent changes in redness. The position of each image was recorded and normalized for a 0 to 100 scale, and compared to chromaticity of each image obtained using a spectrophotometer. The performance of two versions of the scale (5 and 10 images) and a continuous grading scale was evaluated based on repeatability data collected from nineteen observers who used each scale twice to grade 30 randomly presented images of bulbar redness. RESULTS: Psychophysical scaling was highly correlated between single observers (Pearson's r >or= 0.92, p < 0.05). The averaged subjective grades significantly correlated with chromaticity (r = 0.95 and r = 0.99, p < 0.001 for CIE u* and log u*, respectively). Across all observers, test and retest ratings were highly correlated with either scale (r >or= 0.98), and showed high levels of repeatability expressed by intraclass correlation coefficients (ICC >or= 0.98), correlation coefficients of concordance (CCC >or= 0.96), and coefficients of repeatability (COR <or= 5.64). Despite single unit increment options, the majority of grade values assigned using the discrete scales were distributed in multiples of 5. CONCLUSIONS: Combining psychophysical and physical attributes is a promising method for the development of novel anterior segment scales; the newly developed scales performed well in a clinical setting.

Sorbara,L., Simpson,T., Duench,S., Schulze,M., Fonn,D. Comparison of an objective method of measuring bulbar redness to the use of traditional grading scales Contact Lens and Anterior Eye 2007;30(1):53-59 [ Show Abstract ]

Purpose: The primary objective was to compare measures of bulbar redness objectively using a photometric method with standard grading methods. Measures of redness were made on 24 participants wearing a silicone hydrogel contact lens in one eye for overnight wear. This report compares hyperaemia after 1 week of daily wear (baseline) with redness measured after 6 months of overnight wear. Method: A new method of objectively measuring bulbar conjunctival redness was performed using the Spectrascan650® Photometer by Photo Research® under fixed illumination. Photometric measures in CIEu* chromaticity values involve the measurement of chromaticity, a physical analogue of redness, greenness and blueness in the image. This method was validated in Part 1 of the study using repeated measurements on the photographic CCLRU scale. In Part 2 of the study, the photographic grading scale (CCLRU) from 0 (none) to 100 (extreme) was used to make the comparison. Results: Part 1 indicated that the photometer provides a repeatable and reliable measure of bulbar redness (CCC = 0.989). A moderately strong and significant correlation was found between the CIEu* chromaticity values and the analogue data (R = 0.795, p = 0.000) at each measurement session (from baseline to 1 day, 1 week, and 1, 3 and 6 months of overnight wear). Conclusions: This new standardized and objective method of measuring bulbar redness has great potential to replace subjective grading scales, especially with multi-centre studies, where variability between investigators occurs. This method may also detect smaller changes between visits or between eyes. Crown Copyright © 2007.

Scientific Presentations


Luensmann D, Schulze M, Ng AY, Woods J, Jones L. Refitting symptomatic daily disposable contact lens wearers with dry eye disease with delefilcon A lenses Academy at Home, 2020 [ Show Abstract ]

Purpose: To refit symptomatic wearers of daily disposable (DD) contact lenses with a confirmed dry eye diagnosis with Dailies Total1 (delefilcon A, Alcon) to evaluate the performance of the new lenses after one month of wear.
Methods: In this prospective, participant-masked study (over-labelled lenses), symptomatic DD lens wearers were recruited who demonstrated symptoms and signs of dry eye disease according to the TFOS DEWS II criteria. The performance of the lenses after one month was evaluated using subjective ratings and comfort scores, and by determining average wear time and comfortable wear time. Lens wear times as well as subjective symptom scores for comfort, dryness and vision (0-100 scale, with 100 being best) with habitual DD were collected at the screening visit and these results were then compared to delefilcon A after 1 month of wear. The data were not normally distributed, therefore non-parametric analysis (Wilcoxon Matched Pairs Test) was conducted. Data are reported as median (range), with delefilcon A data reported first.
Results: In total, 27 symptomatic DD lens wearers (19 female, 8 male) completed the study. Comfort ratings across all participants were significantly higher (p=0.014) for delefilcon A (80 (40-100)) compared to habitual DD lenses (80 (25-90)). Participants reported less dryness (p=0.007) with delefilcon A compared to their own lenses (80 (40-100) vs 70 (20-95)), and no difference in vision (p>0.05, 90 (50-100) vs (85 (60-100)). There were no statistically significant differences in total hours of lens wear per day (p>0.05, 12.5 hours (6.5-17) vs 11 hours (2.5-16)) or for comfortable wearing time (p>0.05, 8 hours (1-17) vs 6 hours (1-14.8). There were no lens-related ocular findings after one month of delefilcon A wear.
Conclusion: In general, participants had a positive lens wear experience with delefilcon A and rated this lens more comfortable and less dry compared to their habitual DD lenses. This suggests that symptomatic DD lens wearers with dry eye disease may benefit when refit into delefilcon A lenses.

Schulze M, Ng AY, Luensmann D, Guthrie S, Woods J, Jones L. The subjective response to verofilcon A daily disposable contact lenses during extensive digital device use Academy at Home, 2020 [ Show Abstract ]

Purpose: To evaluate the subjective response of habitual lens wearers during extensive digital device use when switched to Precision1 (verofilcon A) daily disposable (DD) contact lenses (CLs).
Methods: Volunteers between 18-40 years of age who used digital devices for at least 6 hours/day while wearing their habitual CLs were recruited for the study. Eligible participants were dispensed with verofilcon A DD CLs for a period of 2 weeks, during which they were required to wear the study CLs for at least 5 days/week and at least 10 hours/day. Participants returned after 142 days for their final visit, where they reported their CL wear time and time spent using digital devices, and rated their typical experience on a 0 to 100 scale, with 100 being best. Comfort, dryness and clarity of vision with verofilcon A were rated directly after insertion, after 6 hours of digital device use, and just before removal, as well as by rating their overall performance. Participants also completed a 4-point (strongly agree, slightly agree, slightly disagree, strongly disagree) Likert scale-based questionnaire. Subjective ratings were not normally distributed, therefore non-parametric analysis was conducted and data are reported as median (range). The Likert scale responses were analyzed using binomial testing.
Results: Twenty participants completed the study (18F:2M), mean age of 25.1 ± 6.0 years (range 19-40). They reported their typical day to include median CL wear time of 13.8 hours (10.5-17), comfortable CL wear time of 12.1 hours (8-16.5) and digital device use of 9 hours (6-12). After 2 weeks of verofilcon A DD CL wear, subjective ratings after 6 hours of digital device use were high, with ratings for a typical day of 93 (68-100) for comfort, 93 (52-100) for dryness and 96 (70-100) for clarity of vision. After 2 weeks of wear, the majority of participants agreed that the study lenses provided good comfort (16/20 subjects; p=0.01) and good vision (18/20; p<0.01) all day long. Similarly, the majority of participants were satisfied with the comfort (16/20; p=0.01), vision (18/20; p<0.01) and overall performance (16/20; p=0.01) they experienced with the study lenses while using digital devices for 6 hours. Additionally, most reported they did not experience any eye strain while using verofilcon A lenses (n=16/20; p=0.01). No significant lens-related ocular findings were observed after 2 weeks of wear.
Conclusions: After 2 weeks of wear, participants rated the performance of verofilcon A DD CLs very highly, with median overall performance ratings for comfort, dryness and vision all 93 on the 0 to 100 scale (with 100 being best). Verofilcon A DD CLs may be a viable alternative for those struggling with their habitual lens performance when spending long hours using digital devices.

Srinivasan S, Jones L, Schulze M, Guillon M, Tauber J, Silverstein S, Yeu E, Venkiteshwar M. Efficacy of a propylene glycol/hydroxypropyl guar-based lubricant eye drop The Association for Research in Vision and Ophthalmology, 2020 [ Show Abstract ][ PDF ]

Purpose : SYSTANE® Complete (propylene glycol/hydroxypropyl guar [PG/HPG]) lubricant eye drop formulation developed using advanced nano-droplet technology, helps replenish a deficient tear film. This study evaluated the improvement in tear film break up time (TFBUT) after 14 days of treatment with PG/HPG lubricant eye drops in patients with dry eye disease (DED).

Methods : This was a Phase IV, multicenter, open-label, single-arm, interventional study. Adult patients with a clinical diagnosis of mild to moderate DED (subtyped into aqueous deficient (ADDE), evaporative dry eye (EDE) and mixed dry eye (MDE)) were included. Eligible patients received one drop of PG/HPG, twice daily. The change from baseline in fluorescein stained tear film break-up time (TFBUT) was assessed at Day 14. Data were analyzed for the overall cohort and by DED subtypes.

Results : Of 134 patients who received the study treatment, 131 completed the study. The median age of the study cohort was 59 (range: 18–87) years, and majority of patients were female (75.4%). Number of patients per subtype were similar (ADE=41; EDE=44; MDE=49). Overall, the median TFBUT increased from 2.68s at baseline to 3.32s at Day 14 (change from baseline= 0.81s; CI for the median = 0.52 -1.18). Subtype analysis showed a median change from baseline in TFBUT of 0.72s for ADDE (CI of median = 0.17-1.22), 1.32s for EDE (CI of median = 0.61-2.26), and 0.55s for MDE (CI of median = 0.07-1.03), at Day 14. The change in TFBUT values were significant overall as well as in the subtypes of DE. The maximum increase in tear film stability was noted in the EDE subgroup (59.2%).

Conclusions : PG/HPG lubricant eye drops increased tear film break up time in patients with DED, with an improvement reported in all dry eye subtypes at Day 14 of treatment. These results show that PG-HPG lubricant eye drops provide an increase in tear film stability in patients with DED.

This is a 2020 ARVO Annual Meeting abstract.


Redfern RL, Nichols J, Sickenberger W, Fogt JS, Schulze M, Lievens C, Szczotka-Flynn L, Schwarz S, Shows A, Lemp-Hull J.. Ex Vivo Analysis of Lipid Deposition with Silicone Hydrogel Contact Lenses and EOBO-Based Lens Care Solutions Investigative Ophthalmology & Vision Science 2018;E-abstract 1768 [ Show Abstract ]

Purpose : To compare the cholesterol deposition profile of a regimen of lotrafilcon B lenses packaged in blister solution containing the EOBO (polyoxyethylene-polyoxybutylene) wetting agent (AIR OPTIX plus HydraGlyde, AOHG) and lens care solutions formulated with EOBO (OPTI-FREE PureMoist, OFPM or CLEAR CARE PLUS, CCP) with a regimen of marketed silicone hydrogel (SiHy) lenses and marketed multipurpose solutions (MPS) that do not contain EOBO.

Methods : Adult, habitual SiHy lens wearers and habitual MPS users participated in a multi-center, prospective, stratified, controlled, parallel-group, masked study. Subjects (n=252) were randomized to wear either AOHG or habitual SiHy lenses (Acuvue Oasys, Acuvue Vita, Biofinity, or Ultra) daily for 30 (+3) days. Subjects in the AOHG lens group were further randomized to use either OFPM or CCP to care for their lenses. Lenses were replaced according to the manufacturer recommendation for each lens material. Subjects assigned to habitual SiHy lenses continued to use their habitual multipurpose solution (HMPS). Lenses (n=20 to 28 per regimen) were collected for assessment of total cholesterol uptake. Cholesterol sorption was measured using a fluorometric enzymatic assay as previously described (Nash et al, E&CL 2014).

Results : AOHG/CCP regimen demonstrated significantly less cholesterol uptake (median = 0.30 µg) than the following regimens: Biofinity/HMPS (median = 1.55 µg), Vita/HMPS (median = 4.20 µg), Ultra/HMPS (median = 1.90 mg) and Oasys/HMPS (median = 1.55 mg), (p < 0.0001 for all). Likewise, the AOHG/OFPM regimen had significantly less cholesterol uptake (median = 0.10 µg) than all habitual lens and solution regimens (p < 0.0001 for all).

Conclusions : The AOHG/CCP and AOHG/OFPM regimens resulted in less cholesterol sorption than each of the habitual SiHy/MPS regimens (p < 0.0001). Further research is necessary to understand the impact of cholesterol deposition on patient clinical outcomes.


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

Schulze M, Wong A, Haider S, Ebare K, Fadli Z, Coles-Brennan C, Jones L. Blink Rate in Silicone Hydrogel Contact Lens Wearers during Digital Device Use The 9th Canadian Optometry School’s Research (COSRC), 2017


Jones L, Varikooty J, Schulze M, Keir N. Assessment of contact lens comfort: Single report scores vs cumulative comfort Asian Cornea and Contact Lens Conference, Hong Kong, 2016

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 ]

Schulze M, Wong A, Haider S, Ebare K, Fadli Z, Coles-Brennan C, Jones L. Blink rate in silicone hydrogel contact lens wearers during digital device use Optom Vis Sci 2016;93: E-abstract 165122 [ PDF ]


Schulze M, Luensmann D, Ng AY, Panjwani F, Srinivasan S, Jones L. The relationship between the positioning of multifocal contact lens optics and satisfaction with vision Optom Vis Sci 2015;92: E-abstract 155256 [ PDF ]

Schulze M, Srinivasan S, Hickson-Curran S, Toubouti Y, Cox S, Mirza A, Nichols J, Morgan P, Jones L. Comparisons between Age, Gender, Lens Type and Lid Wiper Epitheliopathy with Soft Contact Lens Comfort Invest Ophthalmol Vis Sci 2015;56: E-abstract 6069 [ PDF ]


Babaei Omali N, Subbaraman L, Schulze M, Heynen M, Canavan K, Fadli Z, Jones L. Clinical Signs, Symptoms, Tear Film and Meibum Composition in Asymptomatic Senofilcon A Contact Lens and Spectacle Wearers Optom Vis Sci 2014;91: E-abstract 145185 [ PDF ]

Berntsen D, Hickson-Curran S, Jones L, Mathew J, Mirza A, Morgan P, Schulze M, Nichols J. Comparison of soft contact lens comfort using three contact lens materials and four contact lens solutions Invest Ophthalmol Vis Sci 2014;55: E-abstract 863

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 ]

Schulze M, Luensmann D, Hickson-Curran S, Toubouti Y, Cox S, Plowright A, Nichols J, Morgan P, Jones L. Analysis of lid wiper epitheliopathy in habitual soft lens wearers Optom Vis Sci 2014;91: E-abstract 140104

Schulze M, Srinivasan S, Hickson-Curran S, Bemsten D, Howarth G, Nichols J, Morgan P, Jones L. Upper lid margin staining with different soft contact lenses and lens care solution combinations BCLA Clinical Conference and Exhibition, 2014 [ PDF ]

Schulze M, Subbaraman L, Babaei Omali N, Stahl U, Canavan K, Jones L. Is there a difference between clinical signs and symptoms in asymptomatic adapted contact lens and spectacle wearers? BCLA Clinical Conference and Exhibition, 2014 [ PDF ]

Srinivasan S, Schulze M, Hickson-Curran S, Berntsen D, Howarth G, Nichols J, Morgan P, Jones L. Comparison of upper lid margin staining with different soft contact lens materials and care product combinations Invest Ophthalmol Vis Sci 2014;55: E-abstract 4673 [ 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 ]


Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement and repeatability of imaging the meibomian glands with the oculus Keratograph 4 and Keratograph 5M Invest Ophthalmol Vis Sci 2013;54: E-Abstract 3569 [ PDF ]

Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement using infrared meibography systems Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013

Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement and repeatability of imaging the meibomian glands with the Oculus Keratograph 4 and Keratograph 5M Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013

Schulze M, Simpson T, Situ P, Menzies K, Walther H, Jones L. Effects of magnification on tear meniscus parameters using optical coherence tomography (OCT) images Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013


Jerchel N, Sickenberger W, Schulze M. Objective classification and documentation of bulbar redness using a corneal topographer Contact Lens & Anterior Eye 2012;35, S1:e18

Schulze M, Varikooty J, Keir N, Jones L. The clinical performance of three contact lens solutions in symptomatic and asymptomatic contact lens wearers Contact Lens & Anterior Eye 2012;35, S1:e8


Schulze M, Simpson T, Situ P, Menzies K, Walther H, Jones L. Effects of magnification on tear meniscus parameters using optical coherence tomography (OCT) images Optom Vis Sci 2011;88:E-abstract 115482

Schulze M, Simpson T, Stolee P. Rasch Analysis Of Bulbar Redness Scaling And The Relationship Between Physical Redness (u’) and “Rasch Redness” Invest Ophthalmol Vis Sci 2011;52:E-abstract 1966

Simpson T, Schulze M, Stolee P. Rasch Analysis of Clinical Grading of Corneal Staining Invest Ophthalmol Vis Sci 2011;52:E-abstract 1967


Schulze M, Simpson T, Feng Y, Lucchetti E, Chou R, Hutchings N. Statistical Approach for Differentiating Happy and Unhappy Progressive Addition Lens Wearers Optom Vis Sci 2010;87:E-Abstract 105398


Schulze M, Hutchings N, Simpson T. Grading Bulbar Redness using Cross-calibrated Grading Scales Optom Vis Sci 2009;86:E-Abstract 95543

Schulze M, Hutchings N, Simpson T. Clinical Scale Constancy – The Relationship between Bulbar Redness Grading Scales Contact Lens & Anterior Eye 2009;32210-254


Schulze M, Hutchings N, Simpson TL. Perceptual differences between reference images of bulbar redness grading scales Optom Vis Sci 2008;85: E-abstract 80036


Schulze M, Hutchings N, Simpson T. Cross-calibrating between grading scales of redness: is it possible? Biomedical Imaging & Computer Vision (BICV) Conference, Waterloo, ON, CA., 2007

Schulze M, Hutchings N, Simpson T. The use of fractal analysis to estimate the accuracy of bulbar redness grading scales 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007

Schulze M, Simpson TL, Hutchings N. Cross-calibrating between grading scales of redness — is it possible? Invest Ophthalmol Vis Sci 2007;48: E-abstract 5369


Jones D, Schulze M, Simpson T. The Application of Clinical Grading Scales by Trained and Non-trained Observers Contact Lens & Anterior Eye 2001;2523-51

Schulze M, Jones D, Simpson T. The Production of an Enhanced Grading Scale for Determination of Ocular Hyperaemia (BCLA 2001 Da Vinci Award) Contact Lens & Anterior Eye 2001;2523-51


Schulze M, Jones D, Simpson T. The production of an enhanced grading scale for determination of ocular hyperemia Optom Vis Sci 2000;77, 12s:184

Continuing Education Presentations


Walsh K, Schulze M. New Findings to Help Contact Lens Wearers in our New Normal Alberta Association of Optometrists, Webinar. November 3rd, 2020

Professional Publications


Schulze M. Blink Mechanics: Why it Matters Review of Cornea and Contact Lenses 2020;January/February


Schulze M. Summary: IMI Myopia Control Reports Overview and Introduction ContactLensUpdate.com 2019


Schulze M. Blink animation software to improve blinking and dry eye symptoms ContactLensUpdate.com 2018


Schulze M. Summary: Pathophysiology report ContactLensUpdate.com 2017


Schulze M. Summary: Report of the Clinical Trial Design and Outcomes Subcommittee ContactLensUpdate.com 2014

Schulze M. Review of "In vivo 3D meibography of the human eyelid using real time imaging Fourier-Domain OCT" ContactLensUpdate.com 2014



Jones L, Srinivasan S, Ng AY, Schulze M. Clinical Diagnostic Instruments In: Contact Lens Practice; 3rd Ed. Elsevier, Oxford, UK. 2017.


Jones L, Srinivasan S, Ng A, Schulze M. Diagnostic Instruments In: Contact Lens Practice , ed. N Efron. Butterworth Heinemann, UK. 2016.