To describe peripheral defocus when myopic eyes are corrected with spherical and center-distance ... more To describe peripheral defocus when myopic eyes are corrected with spherical and center-distance multifocal soft contact lenses while looking at distance and near. Twenty-five young adults with spherical contact lens-corrected refractive error of -0.50 to -6.00 D participated. Refractive error of each participant's right eye was measured while it wore a spherical soft contact lens (Biofinity) and again while it wore a center-distance multifocal soft contact lens with a +2.50-D add (Biofinity Multifocal "D"). Measurements were made centrally and along the horizontal meridian at ±20, ±30, and ±40 degrees from the line of sight at distance and near (3.33-D demand). The mean (±SD) age and spherical equivalent refractive error were 23.8 ± 1.3 years and -3.62 ± 1.56 D, respectively. At distance, the multifocal contact lens resulted in significantly more myopic defocus than the spherical contact lens at the 40- and 30-degree locations on the nasal retina and at the 20- and 30-degree locations on the temporal retina (p < 0.0001). When accommodating to a near target, peripheral defocus was more myopic with the multifocal lens than with the spherical lens (p < 0.0001). When viewing the near target with the spherical lens, participants experienced foveal hyperopic defocus and peripheral hyperopic defocus at all but one peripheral location. While participants also experienced foveal hyperopic defocus with the multifocal when looking at near, peripheral defocus was minimal (not significantly different than zero) at several locations (i.e., peripheral emmetropia). The center-distance multifocal lens created peripheral myopic defocus when looking at distance. When looking at near, the multifocal lens resulted in relatively more myopic (less hyperopic) peripheral defocus than the spherical lens. The defocus profiles experienced with the multifocal contact lens in this study make it a good candidate for studies seeking to examine the effect of peripheral myopic defocus on myopia progression in children.
To investigate within- and between-operator reliability and validity of refractive index measures... more To investigate within- and between-operator reliability and validity of refractive index measures of hydrogel lenses. Twenty-three lenses of various nominal water contents were examined by two operators on two occasions separated by 1 h. An automated refractometer (CLR 12-70, Index Instruments, Cambridge, UK) was used for refractive index measures. Lenses were presented in a random order to each operator by a third party, and operators were masked to any potential lens identifiers. Intraclass correlation coefficients (ICC), 95% limits of agreement (LoA), and paired t-tests were used to characterize the within- and between-operator reliability and validity of lens refractive index measures. The mean (+/-S.D.) difference between sessions was 0.0001 +/- 0.0011, which did not significantly differ from zero (p = 0.64). Within-operator reliability was excellent (ICC = 0.9990, 95% LoA = -0.0021 to 0.0024). The mean (+/-S.D.) difference between-operators was 0.0002 +/- 0.0010, which was not significantly different from zero (p = 0.54). Between-operator reliability was also excellent (ICC = 0.9984, 95% LoA = -0.0026 to 0.0029). The mean difference between the nominally reported refractive index and our refractive index measures was -0.0009 +/- 0.082, which did not differ statistically from zero (p = 0.52); the 95% LoA for this difference was -0.0152 to 0.0169. There is good reliability within- and between-operators in measuring the refractive index of hydrogel lenses using the CLR 12-70 automated refractometer.
Optometry and vision science : official publication of the American Academy of Optometry, 2016
To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presenta... more To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presentation and after using various SCL and solution combinations. 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. LWE was present in 85% of habitual SCL wearers. LWE was ...
Optometry and vision science : official publication of the American Academy of Optometry, Jan 6, 2016
To evaluate the effect of four contemporary lens care solutions on total protein, total lysozyme,... more To evaluate the effect of four contemporary lens care solutions on total protein, total lysozyme, and active lysozyme extracted from three contact lens materials. Adapted contact lens wearers were recruited at three sites, and all subjects were randomly assigned to daily wear of either etafilcon A, galyfilcon A, or senofilcon A for 2 weeks. Four lens care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and ClearCare) were used by each subject in random order with a new pair of lenses after a washout period between solutions of at least 4 days. After 2 weeks of daily wear, contact lenses were collected for analysis. Proteins were extracted from a subset of contact lenses (n = 568) and total protein, total lysozyme, and lysozyme activity were quantified using a modified Bradford assay, an enzyme-linked immunosorbent assay, and a micrococcal assay, respectively. Higher levels of total protein were extracted from etafilcon A when used with Biotrue compared to other solutions...
Optometry and vision science : official publication of the American Academy of Optometry, Jan 3, 2016
To describe the lid margin characteristics of contact lens wearers and relate them to comfort dur... more To describe the lid margin characteristics of contact lens wearers and relate them to comfort during lens wear. 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. <5), and expressibility (grade 0 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 ...
To compare subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to t... more 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. 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. 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 (&amp;amp;amp;amp;amp;amp;lt;0.5 units); three combinations could increase staining by up to 0.57 units. Staining was &amp;amp;amp;amp;amp;amp;lt;grade 1 for all combinations. Comparable levels of comfort were found between the latest generation of MPSs compared to peroxide disinfection. Three MPS/material combinations tested could result in increased corneal staining of up to 0.57 units versus a peroxide solution. Overall, these data suggest the care systems investigated are generally appropriate for use with the contact lenses tested.
Optometry and vision science : official publication of the American Academy of Optometry, Jan 31, 2016
To evaluate contact lens (CL) storage case contamination when used with four different CL care so... more To evaluate contact lens (CL) storage case contamination when used with four different CL care solutions during daily wear of three different CL materials. A parallel, prospective, bilateral, randomized clinical trial (n = 38) was conducted. Subjects were randomly assigned to use one of three CL materials (etafilcon A, senofilcon A, or galyfilcon A) on a daily wear basis. Subsequently, each subject randomly used one of four different CL care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and CLEAR CARE) for 2 weeks, along with their respective storage cases. After every 2-week period, their storage cases were collected and the right and left wells of each storage case were randomized for two procedures: (1) microbial enumeration by swabbing the storage case surface and (2) evaluation of biofilm formation (multipurpose solution cases only) using a crystal violet staining assay. More than 80% of storage cases were contaminated when used in conjunction with the four CL car...
To assess the reliability of a lissamine green grading scale for conjunctival images. A 20-second... more To assess the reliability of a lissamine green grading scale for conjunctival images. A 20-second video clip of the right eye of 288 contact lens-wearing individuals was recorded using a digital slip-lamp camera after instilling liquid lissamine green. A single nasal and temporal still image were selected. A masked reader used the Oxford grading scale to grade the images on two occasions whereas a second masked reader graded each image on 1 occasion. kappa statistics and 95% confidence intervals (CIs) were used to determine the within- and between-grader reliability overall and when the sample was stratified by age, sex, contact lens type, and disease severity. There was substantial within-grader reliability for both the nasal (kappasimple = 0.69, 95% CI, 0.63-0.75) and temporal (kappasimple = 0.73, 95% CI, 0.67-0.79) images. There was moderate between-grader reliability for both the nasal (kappasimple = 0.51, 95% CI, 0.44-0.58) and temporal (kappasimple = 0.51, 95% CI, 0.44-0.58) images. Age, sex, and contact lens type did not affect within- or between-examiner reliability. There may have been an influence of disease severity on within-examiner reliability, because grading of the temporal images was significantly less reliable in the images with more significant staining. Within- and between-grader reliability of lissamine green staining seems to be at least substantial to moderate. Because the extent of conjunctival staining may influence reliability, this should be considered when studies may include patients with significant staining.
Purpose: To compare subjective comfort across three different contact lens multipurpose solutions... more Purpose: To compare subjective comfort across three different contact lens multipurpose solutions (MPS) to comfort with a peroxide-based solution with three different soft contact lenses. Methods: Habitual soft contact lens wearers were enrolled at three sites and completed a washout period with no contact lens solution by wearing daily disposable lenses (etafilcon A) and spectacles for at least four days. Subjects were then randomly assigned to a 2-week disposable lens type worn on a daily wear basis: etafilcon A, galyfilcon A, or senofilcon A. Subjects wore a new lens of their assigned type for 10-14 days each while using one of four contact lens care solutions, in random order (A - polyaminopropyl biguanide + polyquaternium, B - POLYQUAD + Aldox, C - alexidine + polyquaternium-1, and D - hydrogen peroxide) with a washout period of at least four days using daily disposable lenses and spectacles between each new solution. The Contact Lens User Experience (CLUE) questionnaire was us...
Purpose: To evaluate the amount of upper lid margin staining (ULMS) when using three different so... more Purpose: To evaluate the amount of upper lid margin staining (ULMS) when using three different soft contact lenses (SCL) in combination with four different contact lens care solutions. Methods: Habitual SCL wearers (n=237) were enrolled at three different sites and randomized to wear one of three 2-week disposable SCL types (etafilcon A, galyfilcon A, or senofilcon A) on a daily wear basis for 10-14 days. Each participant was assigned to use four different lens care solutions (A: polyaminopropyl biguanide + polyquaternium; B: POLYQUAD + Aldox; C: alexidine + polyquaternium-1; D: hydrogen peroxide) in a randomly-assigned order, and received a new pair of lenses with each new solution. There was a washout period of at least four days (daily disposable lenses) between solutions. ULMS was assessed with lissamine green and sodium fluorescein dyes. Horizontal length and sagittal width of ULMS were graded from 0 to 3, following the grading scheme proposed by Korb et al. For each dye, horiz...
ABSTRACT Zweck Kindern werden Kontaktlinsen als Korrekturmöglichkeit von Fehlsichtigkeiten nicht ... more ABSTRACT Zweck Kindern werden Kontaktlinsen als Korrekturmöglichkeit von Fehlsichtigkeiten nicht annähernd so häufig angeboten wie Jugendlichen. Dieser Beitrag untersucht die Vorteile des Kontaktlinsentragens für Kinder und Jugendliche, um festzustellen, ob Kinder davon genauso profitieren wie Jugendliche. Falls ja, sollten Kontaktlinsen Kindern routinemäßig als Behandlungsmethode für Fehlsichtigkeiten angeboten werden. Material und Methoden Personen, die noch nie zuvor Kontaktlinsen getragen hatten, wurden in 2 Gruppen – Kinder (8–12 Jahre) und Jugendliche (13–17 Jahre) – eingeteilt. Sie füllten zunächst ein sog. Pediatric Refractive Error Profile (PREP) aus. Dabei handelt es sich um eine pädiatrische Umfrage zur Lebensqualität von Menschen, bei denen eine Fehlsichtigkeit vorliegt und die eine Brille tragen. Danach wurden ihnen Kontaktlinsen aus Silikonhydrogel angepasst. Eine Woche, einen Monat sowie 3 Monate, nachdem sie die Kontaktlinsen erhalten hatten, füllten die Probanden den PREP-Fragebogen erneut aus. Die Probanden beantworteten auch Fragen zur Tragezeit und Zufriedenheit mit den Kontaktlinsen während bestimmter Aktivitäten. Ergebnisse An der Studie nahmen 169 Probanden in 3 klinischen Zentren teil. Insgesamt 93 Probanden (55 %) waren Mädchen; 78 Probanden (46 %) waren Weiße; 44 Probanden (26 %) waren hispanischer Herkunft. Nachdem die Kontaktlinsen 3 Monate lang getragen worden waren, stieg die PREP-Gesamtbewertung bei Kindern von 64,4 während des Brillentragens auf 79,2 und bei Jugendlichen von 61,8 während des Brillentragens auf 76,5. Die Verbesserung nach 3 Monaten im Vergleich zum Ausgangswert war sowohl für Kinder als auch für Jugendliche signifikant (p &lt; 0,0001 für beide Gruppen), jedoch gab es keinen signifikanten Unterschied in der Verbesserung der Ausgangswerte zwischen Kindern und Jugendlichen (p &gt; 0,05). Die größten Verbesserungen wurden im Hinblick auf die Zufriedenheit mit der Sehkorrektur, bezüglich Aktivitäten sowie bezüglich des äußeren Erscheinungsbilds wahrgenommen. Schlussfolgerungen Kontaktlinsen bedeuten eine erhebliche Verbesserung der Lebensqualität. Dies berichteten sowohl Kinder als auch Jugendliche, die das PREP ausfüllten, wobei es in der Beurteilung der Verbesserung keine Unterschiede zwischen Kindern und Jugendlichen gab. Durch das Tragen von Kontaktlinsen verbessert sich die Einstellung der Kinder und Jugendlichen zu ihrem Aussehen und ihrer Teilnahme an Aktivitäten dramatisch, was zu einer größeren Zufriedenheit mit der bei ihnen vorgenommenen Sehkorrektur führt. Die Verbesserung der Lebensqualität durch das Tragen von Kontaktlinsen zeigt, dass Kindern Kontaktlinsen als Alternative für die Korrektur ihrer Fehlsichtigkeit genauso routinemäßig angeboten werden sollten wie Jugendlichen.
Optometry and vision science : official publication of the American Academy of Optometry, 2013
To determine the repeatability of eye length measurements made centrally and off-axis using a low... more To determine the repeatability of eye length measurements made centrally and off-axis using a low-coherence interferometer. Eye length was measured (left eye) in 29 adults using the Haag-Streit Lenstar LS 900. Five measurements were made centrally, 10 degrees temporally, and 10 degrees nasally on the retina by the same examiner at two separate visits. Intervisit repeatability was assessed by plotting the difference versus the mean of each pair of measurements (bias) and calculating the 95% limits of agreement (LoA). Within-session repeatability was determined by calculating the within-subject SD (Sw) of five consecutive measurements at a visit. Because of variability noted 10 degrees nasally, the Sw was also determined on a subset of 10 subjects using five measurements at one visit 30 degrees nasally and 30 degrees temporally. The mean ± SD age, spherical equivalent refractive error, and central axial length (at visit 1) were 24.0 ± 1.4 years, -3.46 ± 2.69 diopters, and 24.91 ± 1.10...
Optometry and vision science : official publication of the American Academy of Optometry, 2009
To determine the on-eye effect of spherical and toric contact lens design on higher-order aberrat... more To determine the on-eye effect of spherical and toric contact lens design on higher-order aberrations (HOA). Thirty eyes (15 subjects) entered a masked, randomized, cross-over study. Each eye was fitted with the spherical and toric lens of the following brands in random order: Acuvue Advance, Biomedics 55, Frequency 55, and SofLens 66. HOAs were measured using the Zywave II Aberrometer over a 6-mm aperture up to fifth order. A linear model accounting for the fixed effect of lens type and random effects of subject and eye was created. Paired t-tests were completed between lens brands within the spherical and toric lenses and between the spherical and toric lens within each brand. Best-corrected visual acuity (VA) was measured and compared. No clinically meaningful differences in total HOAs were found between brands or between the spherical and toric lens within a brand. Positive spherical aberration (SA) was reduced by all spherical and toric lenses compared to wearing no lens by 0.0...
To describe peripheral defocus when myopic eyes are corrected with spherical and center-distance ... more To describe peripheral defocus when myopic eyes are corrected with spherical and center-distance multifocal soft contact lenses while looking at distance and near. Twenty-five young adults with spherical contact lens-corrected refractive error of -0.50 to -6.00 D participated. Refractive error of each participant&amp;amp;#39;s right eye was measured while it wore a spherical soft contact lens (Biofinity) and again while it wore a center-distance multifocal soft contact lens with a +2.50-D add (Biofinity Multifocal &amp;amp;quot;D&amp;amp;quot;). Measurements were made centrally and along the horizontal meridian at ±20, ±30, and ±40 degrees from the line of sight at distance and near (3.33-D demand). The mean (±SD) age and spherical equivalent refractive error were 23.8 ± 1.3 years and -3.62 ± 1.56 D, respectively. At distance, the multifocal contact lens resulted in significantly more myopic defocus than the spherical contact lens at the 40- and 30-degree locations on the nasal retina and at the 20- and 30-degree locations on the temporal retina (p &amp;amp;lt; 0.0001). When accommodating to a near target, peripheral defocus was more myopic with the multifocal lens than with the spherical lens (p &amp;amp;lt; 0.0001). When viewing the near target with the spherical lens, participants experienced foveal hyperopic defocus and peripheral hyperopic defocus at all but one peripheral location. While participants also experienced foveal hyperopic defocus with the multifocal when looking at near, peripheral defocus was minimal (not significantly different than zero) at several locations (i.e., peripheral emmetropia). The center-distance multifocal lens created peripheral myopic defocus when looking at distance. When looking at near, the multifocal lens resulted in relatively more myopic (less hyperopic) peripheral defocus than the spherical lens. The defocus profiles experienced with the multifocal contact lens in this study make it a good candidate for studies seeking to examine the effect of peripheral myopic defocus on myopia progression in children.
To investigate within- and between-operator reliability and validity of refractive index measures... more To investigate within- and between-operator reliability and validity of refractive index measures of hydrogel lenses. Twenty-three lenses of various nominal water contents were examined by two operators on two occasions separated by 1 h. An automated refractometer (CLR 12-70, Index Instruments, Cambridge, UK) was used for refractive index measures. Lenses were presented in a random order to each operator by a third party, and operators were masked to any potential lens identifiers. Intraclass correlation coefficients (ICC), 95% limits of agreement (LoA), and paired t-tests were used to characterize the within- and between-operator reliability and validity of lens refractive index measures. The mean (+/-S.D.) difference between sessions was 0.0001 +/- 0.0011, which did not significantly differ from zero (p = 0.64). Within-operator reliability was excellent (ICC = 0.9990, 95% LoA = -0.0021 to 0.0024). The mean (+/-S.D.) difference between-operators was 0.0002 +/- 0.0010, which was not significantly different from zero (p = 0.54). Between-operator reliability was also excellent (ICC = 0.9984, 95% LoA = -0.0026 to 0.0029). The mean difference between the nominally reported refractive index and our refractive index measures was -0.0009 +/- 0.082, which did not differ statistically from zero (p = 0.52); the 95% LoA for this difference was -0.0152 to 0.0169. There is good reliability within- and between-operators in measuring the refractive index of hydrogel lenses using the CLR 12-70 automated refractometer.
Optometry and vision science : official publication of the American Academy of Optometry, 2016
To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presenta... more To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presentation and after using various SCL and solution combinations. 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. LWE was present in 85% of habitual SCL wearers. LWE was ...
Optometry and vision science : official publication of the American Academy of Optometry, Jan 6, 2016
To evaluate the effect of four contemporary lens care solutions on total protein, total lysozyme,... more To evaluate the effect of four contemporary lens care solutions on total protein, total lysozyme, and active lysozyme extracted from three contact lens materials. Adapted contact lens wearers were recruited at three sites, and all subjects were randomly assigned to daily wear of either etafilcon A, galyfilcon A, or senofilcon A for 2 weeks. Four lens care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and ClearCare) were used by each subject in random order with a new pair of lenses after a washout period between solutions of at least 4 days. After 2 weeks of daily wear, contact lenses were collected for analysis. Proteins were extracted from a subset of contact lenses (n = 568) and total protein, total lysozyme, and lysozyme activity were quantified using a modified Bradford assay, an enzyme-linked immunosorbent assay, and a micrococcal assay, respectively. Higher levels of total protein were extracted from etafilcon A when used with Biotrue compared to other solutions...
Optometry and vision science : official publication of the American Academy of Optometry, Jan 3, 2016
To describe the lid margin characteristics of contact lens wearers and relate them to comfort dur... more To describe the lid margin characteristics of contact lens wearers and relate them to comfort during lens wear. 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. <5), and expressibility (grade 0 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 ...
To compare subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to t... more 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. 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. 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 (&amp;amp;amp;amp;amp;amp;lt;0.5 units); three combinations could increase staining by up to 0.57 units. Staining was &amp;amp;amp;amp;amp;amp;lt;grade 1 for all combinations. Comparable levels of comfort were found between the latest generation of MPSs compared to peroxide disinfection. Three MPS/material combinations tested could result in increased corneal staining of up to 0.57 units versus a peroxide solution. Overall, these data suggest the care systems investigated are generally appropriate for use with the contact lenses tested.
Optometry and vision science : official publication of the American Academy of Optometry, Jan 31, 2016
To evaluate contact lens (CL) storage case contamination when used with four different CL care so... more To evaluate contact lens (CL) storage case contamination when used with four different CL care solutions during daily wear of three different CL materials. A parallel, prospective, bilateral, randomized clinical trial (n = 38) was conducted. Subjects were randomly assigned to use one of three CL materials (etafilcon A, senofilcon A, or galyfilcon A) on a daily wear basis. Subsequently, each subject randomly used one of four different CL care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and CLEAR CARE) for 2 weeks, along with their respective storage cases. After every 2-week period, their storage cases were collected and the right and left wells of each storage case were randomized for two procedures: (1) microbial enumeration by swabbing the storage case surface and (2) evaluation of biofilm formation (multipurpose solution cases only) using a crystal violet staining assay. More than 80% of storage cases were contaminated when used in conjunction with the four CL car...
To assess the reliability of a lissamine green grading scale for conjunctival images. A 20-second... more To assess the reliability of a lissamine green grading scale for conjunctival images. A 20-second video clip of the right eye of 288 contact lens-wearing individuals was recorded using a digital slip-lamp camera after instilling liquid lissamine green. A single nasal and temporal still image were selected. A masked reader used the Oxford grading scale to grade the images on two occasions whereas a second masked reader graded each image on 1 occasion. kappa statistics and 95% confidence intervals (CIs) were used to determine the within- and between-grader reliability overall and when the sample was stratified by age, sex, contact lens type, and disease severity. There was substantial within-grader reliability for both the nasal (kappasimple = 0.69, 95% CI, 0.63-0.75) and temporal (kappasimple = 0.73, 95% CI, 0.67-0.79) images. There was moderate between-grader reliability for both the nasal (kappasimple = 0.51, 95% CI, 0.44-0.58) and temporal (kappasimple = 0.51, 95% CI, 0.44-0.58) images. Age, sex, and contact lens type did not affect within- or between-examiner reliability. There may have been an influence of disease severity on within-examiner reliability, because grading of the temporal images was significantly less reliable in the images with more significant staining. Within- and between-grader reliability of lissamine green staining seems to be at least substantial to moderate. Because the extent of conjunctival staining may influence reliability, this should be considered when studies may include patients with significant staining.
Purpose: To compare subjective comfort across three different contact lens multipurpose solutions... more Purpose: To compare subjective comfort across three different contact lens multipurpose solutions (MPS) to comfort with a peroxide-based solution with three different soft contact lenses. Methods: Habitual soft contact lens wearers were enrolled at three sites and completed a washout period with no contact lens solution by wearing daily disposable lenses (etafilcon A) and spectacles for at least four days. Subjects were then randomly assigned to a 2-week disposable lens type worn on a daily wear basis: etafilcon A, galyfilcon A, or senofilcon A. Subjects wore a new lens of their assigned type for 10-14 days each while using one of four contact lens care solutions, in random order (A - polyaminopropyl biguanide + polyquaternium, B - POLYQUAD + Aldox, C - alexidine + polyquaternium-1, and D - hydrogen peroxide) with a washout period of at least four days using daily disposable lenses and spectacles between each new solution. The Contact Lens User Experience (CLUE) questionnaire was us...
Purpose: To evaluate the amount of upper lid margin staining (ULMS) when using three different so... more Purpose: To evaluate the amount of upper lid margin staining (ULMS) when using three different soft contact lenses (SCL) in combination with four different contact lens care solutions. Methods: Habitual SCL wearers (n=237) were enrolled at three different sites and randomized to wear one of three 2-week disposable SCL types (etafilcon A, galyfilcon A, or senofilcon A) on a daily wear basis for 10-14 days. Each participant was assigned to use four different lens care solutions (A: polyaminopropyl biguanide + polyquaternium; B: POLYQUAD + Aldox; C: alexidine + polyquaternium-1; D: hydrogen peroxide) in a randomly-assigned order, and received a new pair of lenses with each new solution. There was a washout period of at least four days (daily disposable lenses) between solutions. ULMS was assessed with lissamine green and sodium fluorescein dyes. Horizontal length and sagittal width of ULMS were graded from 0 to 3, following the grading scheme proposed by Korb et al. For each dye, horiz...
ABSTRACT Zweck Kindern werden Kontaktlinsen als Korrekturmöglichkeit von Fehlsichtigkeiten nicht ... more ABSTRACT Zweck Kindern werden Kontaktlinsen als Korrekturmöglichkeit von Fehlsichtigkeiten nicht annähernd so häufig angeboten wie Jugendlichen. Dieser Beitrag untersucht die Vorteile des Kontaktlinsentragens für Kinder und Jugendliche, um festzustellen, ob Kinder davon genauso profitieren wie Jugendliche. Falls ja, sollten Kontaktlinsen Kindern routinemäßig als Behandlungsmethode für Fehlsichtigkeiten angeboten werden. Material und Methoden Personen, die noch nie zuvor Kontaktlinsen getragen hatten, wurden in 2 Gruppen – Kinder (8–12 Jahre) und Jugendliche (13–17 Jahre) – eingeteilt. Sie füllten zunächst ein sog. Pediatric Refractive Error Profile (PREP) aus. Dabei handelt es sich um eine pädiatrische Umfrage zur Lebensqualität von Menschen, bei denen eine Fehlsichtigkeit vorliegt und die eine Brille tragen. Danach wurden ihnen Kontaktlinsen aus Silikonhydrogel angepasst. Eine Woche, einen Monat sowie 3 Monate, nachdem sie die Kontaktlinsen erhalten hatten, füllten die Probanden den PREP-Fragebogen erneut aus. Die Probanden beantworteten auch Fragen zur Tragezeit und Zufriedenheit mit den Kontaktlinsen während bestimmter Aktivitäten. Ergebnisse An der Studie nahmen 169 Probanden in 3 klinischen Zentren teil. Insgesamt 93 Probanden (55 %) waren Mädchen; 78 Probanden (46 %) waren Weiße; 44 Probanden (26 %) waren hispanischer Herkunft. Nachdem die Kontaktlinsen 3 Monate lang getragen worden waren, stieg die PREP-Gesamtbewertung bei Kindern von 64,4 während des Brillentragens auf 79,2 und bei Jugendlichen von 61,8 während des Brillentragens auf 76,5. Die Verbesserung nach 3 Monaten im Vergleich zum Ausgangswert war sowohl für Kinder als auch für Jugendliche signifikant (p &lt; 0,0001 für beide Gruppen), jedoch gab es keinen signifikanten Unterschied in der Verbesserung der Ausgangswerte zwischen Kindern und Jugendlichen (p &gt; 0,05). Die größten Verbesserungen wurden im Hinblick auf die Zufriedenheit mit der Sehkorrektur, bezüglich Aktivitäten sowie bezüglich des äußeren Erscheinungsbilds wahrgenommen. Schlussfolgerungen Kontaktlinsen bedeuten eine erhebliche Verbesserung der Lebensqualität. Dies berichteten sowohl Kinder als auch Jugendliche, die das PREP ausfüllten, wobei es in der Beurteilung der Verbesserung keine Unterschiede zwischen Kindern und Jugendlichen gab. Durch das Tragen von Kontaktlinsen verbessert sich die Einstellung der Kinder und Jugendlichen zu ihrem Aussehen und ihrer Teilnahme an Aktivitäten dramatisch, was zu einer größeren Zufriedenheit mit der bei ihnen vorgenommenen Sehkorrektur führt. Die Verbesserung der Lebensqualität durch das Tragen von Kontaktlinsen zeigt, dass Kindern Kontaktlinsen als Alternative für die Korrektur ihrer Fehlsichtigkeit genauso routinemäßig angeboten werden sollten wie Jugendlichen.
Optometry and vision science : official publication of the American Academy of Optometry, 2013
To determine the repeatability of eye length measurements made centrally and off-axis using a low... more To determine the repeatability of eye length measurements made centrally and off-axis using a low-coherence interferometer. Eye length was measured (left eye) in 29 adults using the Haag-Streit Lenstar LS 900. Five measurements were made centrally, 10 degrees temporally, and 10 degrees nasally on the retina by the same examiner at two separate visits. Intervisit repeatability was assessed by plotting the difference versus the mean of each pair of measurements (bias) and calculating the 95% limits of agreement (LoA). Within-session repeatability was determined by calculating the within-subject SD (Sw) of five consecutive measurements at a visit. Because of variability noted 10 degrees nasally, the Sw was also determined on a subset of 10 subjects using five measurements at one visit 30 degrees nasally and 30 degrees temporally. The mean ± SD age, spherical equivalent refractive error, and central axial length (at visit 1) were 24.0 ± 1.4 years, -3.46 ± 2.69 diopters, and 24.91 ± 1.10...
Optometry and vision science : official publication of the American Academy of Optometry, 2009
To determine the on-eye effect of spherical and toric contact lens design on higher-order aberrat... more To determine the on-eye effect of spherical and toric contact lens design on higher-order aberrations (HOA). Thirty eyes (15 subjects) entered a masked, randomized, cross-over study. Each eye was fitted with the spherical and toric lens of the following brands in random order: Acuvue Advance, Biomedics 55, Frequency 55, and SofLens 66. HOAs were measured using the Zywave II Aberrometer over a 6-mm aperture up to fifth order. A linear model accounting for the fixed effect of lens type and random effects of subject and eye was created. Paired t-tests were completed between lens brands within the spherical and toric lenses and between the spherical and toric lens within each brand. Best-corrected visual acuity (VA) was measured and compared. No clinically meaningful differences in total HOAs were found between brands or between the spherical and toric lens within a brand. Positive spherical aberration (SA) was reduced by all spherical and toric lenses compared to wearing no lens by 0.0...
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Papers by David Berntsen