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Purpose: This study aimed to identify baseline factors associated with greater myopia progression and axial elongation in children with myopia., Methods: This study performed a post hoc analysis of data from a 30-month randomized trial of atropine 0.01% versus placebo in children 5 to <13 years old with baseline spherical equivalent refractive error (SER) of -1.00 to -6.00 D, astigmatism of ≤1.50 D, and anisometropia of <1.00 D SER. Data from atropine 0.01% and placebo groups were pooled given outcomes were similar. Baseline factors of age, SER, axial length, race, sex, parental myopia, and iris color were evaluated for association with changes in SER and with changes in axial length at 30 months (24 months on treatment and then 6 months off) using backward model selection., Results: Among 187 randomized participants, 175 (94%) completed 30 months of follow-up. The mean change in SER was greater among younger children (-0.19 D per 1 year younger; 95% confidence interval [CI], -0.25 to -0.14 D; p<0.001) and children with higher myopia (-0.14 D per 1 D more myopia at baseline; 95% CI, -0.23 to -0.05 D; p=0.002). The mean change in axial length was also greater among younger children (0.13 mm per 1 year younger; 95% CI, 0.10 to 0.15 mm; p<0.001) and children with higher baseline myopia (0.04 mm per 1 D more myopia; 95% CI, 0.002 to 0.08; p=0.04)., Conclusions: Younger children with higher myopia had greater myopic progression and axial elongation over 30 months than older children with lower myopia. Developing effective treatments to slow the faster myopic progression in younger children should be a target of further research., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding organizations., (Copyright © 2024 American Academy of Optometry.)

Significance: This study explores the difference between cycloplegic and noncycloplegic refraction in young adult myopes., Purpose: From the available literature, it is unclear whether cycloplegia is necessary when refracting young adults. This study investigates the agreement between noncycloplegic autorefraction and cycloplegic autorefraction and investigates factors affecting the agreement between the two methods., Methods: In total, 125 myopes with ages ranging between 18 and 26 years were included from Australia and Vietnam. Each participant underwent noncycloplegic autorefraction and cycloplegic autorefraction. Cycloplegia was induced with 1% ophthalmic tropicamide., Results: The mean spherical equivalent difference (95% confidence interval) between noncycloplegic autorefraction and cycloplegic autorefraction was -0.20 D (-0.25 to -0.14 D; t124 = -7.18, p<0.0001 ) . A mean difference of >0.25 D was seen in 46.8% of eyes. The lower and upper limits of agreement were -0.80 and 0.41 D, respectively. With univariate analysis, factors including age, degree of refractive error, accommodation amplitude, and distance phorias showed no impact on the average difference between cycloplegic autorefraction and noncycloplegic autorefraction. Yet, eyes with near exophoria ( F2,120 = 6.63, p=0.0019) and Caucasian eyes ( F3,121 = 2.85, p=0.040) exhibited the smallest paired differences. However, in the multivariate analysis, only near exophoria was associated with a lower mean difference. A significantly smaller proportion (34.9%) of eyes with near exophoria had a paired difference of -0.25 D or more compared with esophoria (50%) and orthophoria (65%; χ2 = 6.6, p=0.038)., Conclusions: Noncycloplegic autorefraction results in more myopic refractive error than cycloplegic autorefraction in young adults., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 The Author(s).)

Significance: After a dilated eye examination, many patients experience symptoms of prolonged light sensitivity, blurred vision, and cycloplegia associated with pharmacological mydriasis. Phentolamine mesylate ophthalmic solution (PMOS) may expedite the reversal of mydriasis in patients, potentially facilitating return to functional vision and reducing barriers to obtaining dilated eye examinations., Purpose: The protracted reversal time after pharmacologically induced pupil dilation impairs vision. We tested the hypothesis that PMOS rapidly reduces pupil diameter in this acute indication., Methods: In this double-masked placebo-controlled, randomized, two-arm crossover phase 2b trial, we evaluated the effects of one drop of 1% PMOS applied bilaterally in subjects who had their pupils dilated by one of two common mydriatic agents: 2.5% phenylephrine or 1% tropicamide. End points included change in pupil diameter, percent of subjects returning to baseline pupil diameter, and accommodative function at multiple time points., Results: Thirty-one subjects completed the study (15 dilated with phenylephrine and 16 with tropicamide). Change in pupil diameter from baseline at 2 hours after maximal dilation with 1% PMOS was -1.69 mm and was significantly greater in magnitude compared with placebo for every time point beyond 30 minutes (P < .05). At 2 hours, a greater percentage of study eyes given 1% PMOS returned to baseline pupil diameter compared with placebo (29 vs. 13%, P = .03), which was this also seen at 4 hours (P < .001). More subjects treated with PMOS in the tropicamide subgroup had at least one eye returning to baseline accommodative amplitude at 2 hours (63 vs. 38%, P = .01). There were no severe adverse events, with only mild to moderate conjunctival hyperemia that resolved in most patients by 6 hours., Conclusions: Phentolamine mesylate ophthalmic solution at 1% reversed medically induced pupil dilation more rapidly than placebo treatment regardless of which mydriatic was used (adrenergic agonists and cholinergic blockers) with a tolerable safety profile., Competing Interests: Conflict of Interest Disclosure: The publication of this article was sponsored by Ocuphire Pharma, Inc. ARM, MPS, RMJ, KC, JEY, SAK, and ATA are or were employees, directors/officers, or paid consultants for Ocuphire Pharma. PMK, MBM, ESL, JSP, and GDH are on the medical advisory board for Ocuphire Pharma. PMK, SAF, SMM, and SRK were principal investigators for this clinical trial funded by Ocuphire Pharma. CBS serves as Chief Medical Officer of Oculos Development Services, LLC, which was the contract research organization for this clinical trial. The authors indicated that they have no other conflicts of interest with regard to the content of this article. The authors listed report a financial conflict of interest (PMK, SAF, SMM, SRK, CBS, ARM, MPS, RMJ, KC, JEY, SAK, ATA, MBM, GDH, ESL, and JSP). The sponsor (Ocuphire) provided financial and material support and participated in study design, analysis, and interpretation. The authors were responsible for the preparation of this article and the decision to submit this article for publication. Each of the authors had (full/limited) access to the study data and takes full responsibility for their presentation in this article., (Copyright © 2021 American Academy of Optometry.)

Significance: It is apparent that a variety of biometric changes are caused by different types of cycloplegic eye drops. However, these effects are inconsistent and have not been reported in different refractive groups., Purpose: The purpose of this study was to determine the effect of cyclopentolate 1% on ocular biometric components in different types of refractive errors in children., Methods: This cross-sectional study was conducted on 226 eyes of 113 schoolchildren in Shahroud, northeast Iran, with a mean ± standard deviation age of 9.20 ± 1.65 years. All participants had noncycloplegic and cycloplegic objective refraction using an autorefractometer. Cycloplegia was induced using cyclopentolate 1% eye drops. Biometric measurements were made with Allegro Biograph (WaveLight AG, Erlangen, Germany) before and after administering cycloplegic drops. Mixed-effect model regression was used to analyze the data., Results: After cycloplegia, the vitreous chamber depth (VCD) (-0.043; 95% confidence interval [CI], -0.067 to -0.019 mm), lens thickness (-0.146; 95% CI, -0.175 to -0.117 mm), axial length (-0.009; 95% CI, -0.012 to -0.006 mm), and lens power (-0.335; 95% CI, -0.463 to -0.208 D) decreased significantly, whereas the anterior chamber depth (ACD) (0.183; 95% CI, 0.164 to 0.202 mm), anterior segment length (0.036; 95% CI, 0.014 to 0.058) mm), lens central point (0.109; 95% CI, 0.094 to 0.124 mm), and pupil diameter (1.599; 95% CI, 1.482 to 1.716 mm) increased (P value for all tests, <.001). For changes in VCD and ACD, a significant interaction was observed between different types of refractive errors and cycloplegia, such that the adjusted mean change for ACD was significantly lower and for VCD was significantly higher in hyperopes compared with emmetropes. Lens center moves backward in myopes (0.17 mm) and stays the same in hyperopes under cycloplegia., Conclusions: According to the findings of this study, cycloplegia reduces the thickness of the crystalline lens and subsequently causes an increase in the ACD. Cycloplegia-related ocular biometric changes were different by type of refractive error.

Significance: The Welch Allyn SureSight (Welch Allyn, Skaneateles Falls, NY) and Plusoptix PowerRefractor (Plusoptix, Nuremberg, Germany) are often used with infants, but little is known about the repeatability and validity of their peripheral refractive error measurements. Selecting the best instrument will support future refractive error and emmetropization studies., Purpose: The purpose of this study was to determine the validity and repeatability of peripheral refractive error measurements and peripheral refraction profiles measured with the Welch Allyn SureSight and Plusoptix PowerRefractor compared with the criterion standard Grand Seiko WR-5100K (Grand Seiko Co., Hiroshima, Japan)., Methods: Cycloplegic (tropicamide 1%) autorefraction was measured in the right eyes of 21 adult subjects (31.4 ± 10.4 years) with the three instruments in randomized order on two separate visits, at least 24 hours apart, centrally, and at 30 and 20° temporal and nasal gaze., Results: The SureSight measurements were within 0.24 D and not significantly different from the Grand Seiko WR-5100K in any gaze (P < .65), whereas the PowerRefractor measurements were more myopic by as much as -0.97 D and significantly different in four of the five gaze directions (P < .04). The 95% limits of agreement between occasions by gaze ranged from ±0.38 to ±0.61 D for the SureSight, similar to or slightly better than the WR-5100K (±0.31 to ±1.51 D) and the PowerRefractor (±0.72 to ±1.71 D). There were no significant differences between visits for any instrument in any gaze (P < .94). The repeatability of the SureSight was also better than that for the Grand Seiko when peripheral refraction was represented by quadratic fits to the data., Conclusions: These findings suggest that the Welch Allyn SureSight is the most suitable portable autorefractor to use to monitor peripheral autorefraction based on better repeatability between occasions and better validity compared with the criterion standard Grand Seiko WR-5100K.

Significance: Increasing prevalence of refractive error requires assessment of ametropia as a screening tool in children. If cycloplegia is not an option, knowledge about the increase in uncertainty for wavefront-based autorefraction is needed. The cycloplegic agent as the principal variant presents cross-reference and allows for extraction of the influence of accommodation., Purpose: The purpose of this study was to determine the repeatability, agreement, and propensity to accommodate of cycloplegic (ARc) and noncycloplegic (ARnc) wavefront-based autorefraction (ZEISS i.Profiler plus; Carl Zeiss Vision, Aalen, Germany) in children aged 2 to 15 years., Methods: In a clinical setting, three consecutive measurements were feasible for 145 eyes (OD) under both conditions. Data are described by spherical equivalent (M), horizontal or vertical astigmatic component (J0), and oblique astigmatic component (J45). In the case of M, the most positive value of the three measurements was chosen, whereas the mean was applied for astigmatic components., Results: Regarding agreement, differences for ARc minus ARnc were statistically significant: for M, 0.55 (0.55 D; mean [SD]; P < .001), that is, more hyperopic in cycloplegia; for J0, -0.03 (0.11 D; P = .002); and for J45, -0.03 D (SD, 0.09 D; P < .001). Regarding repeatability, astigmatic components showed excellent repeatability: SD < 0.11 D (ARnc) and SD < 0.09 D (ARc). The repeatability of M was SD = 0.57 D with a 95% interval of 1.49 D (ARnc). Under cycloplegia, this decreased to SD = 0.17 D (ARc) with a 95% interval of 0.50 D. The mean propensity to accommodate was 0.44 D from repeated measurements; in cycloplegia, this was reduced to 0.19 D., Conclusions: Wavefront-based refraction measurement results are highly repeatable and precise for astigmatic components. Noncycloplegic measurements of M show a systematic bias of 0.55 D. Cycloplegia reduces the propensity to accommodate by a factor of 2.4; for noncycloplegic repeated measurements, accommodation is controlled to a total interval of 1.49 D (95%). Without cycloplegia, results improve drastically when measurements are repeated.

Significance: Pharmaceutical companies recommend discarding ophthalmic drugs 28 days after opening. This study shows that diagnostic eye drops have a low risk of contamination over a 7-month period in a controlled clinical setup. The diagnostic efficiency seems to be preserved over this period., Purpose: The aim of this study was to evaluate the preservation period and the efficacy of ophthalmic preparations, such as 0.5% proparacaine hydrochloride, 1% tropicamide, 2.5% phenylephrine hydrochloride, and 1% cyclopentolate hydrochloride ophthalmic solution in a clinical and controlled setting., Methods: Thirty-eight primary eye care students were recruited to participate in the study. They used 25 bottles of each diagnostic drop at the Clinique Universitaire de la Vision for a 7-month period. An analysis of the bacterial contamination was repeated 10 times using both an agar plate and a nutrient broth at 0, 2, 4, 6, and 8 weeks and at 3, 4, 5, 6, and 7 months. The anesthetic, mydriatic, and cycloplegic effects were tested after 7 months of use and compared with nonopened ophthalmic bottles., Results: During the 7-month period, 4971 drops of proparacaine, 3219 drops of tropicamide and phenylephrine, and 1896 drops of cyclopentolate were administered to the patients. A total of 226 contacts between bottles and biological tissues were reported. After the 10 inoculation sessions on the agar medium at the predetermined times, no bacterial and fungal contamination was noted. No patient reported eye infections for 2 weeks after the drop instillation. Moreover, there was no difference in the efficacy when compared with new drops., Conclusions: According to the results of the current study, diagnostic eye drops can be used with a low contamination risk beyond the recommendation date of 28 days up to 7 months, with the same efficacy, in a controlled clinical context.

Significance: This study demonstrates that mean axial length/corneal radius of curvature ratio (AL/CR) can be used to detect low and high myopia but cannot clinically monitor myopia progression because the relationship between AL/CR and progression in myopia is different between low and high myopia., Purpose: The purpose of this study was to investigate the relationship of AL/CR with magnitude and progression of myopia., Methods: Retrospective analysis was conducted comparing the right eyes of those with high myopia (n = 308; age, 7 to 16 years; myopia sphere, -6.00 diopters or worse) with those with low myopia (n = 732; age, 7 to 16 years; myopia sphere, between -0.50 and -3.50 diopters; cylinder, ≤1.00 diopters). Baseline axial length, corneal radii of curvature, and cycloplegic objective refraction were analyzed. Myopia progression in the low-myopia group at 6- and 12-month follow-up was measured, and the differences in slopes of AL/CR were compared for slow (<0.75 diopters) and fast progressing (≥0.75 diopters)., Results: Mean AL/CR values were significantly different (P < .001) between high myopia (3.46 ± 0.10) and low myopia (3.16 ± 0.07). In high and low myopia, slopes of axial length versus corneal curvature radius were not significantly different (P > .05), and slopes of AL/CR versus spherical equivalent were significantly different after adjusting for spherical equivalent and age (P < .05). Slopes of AL/CR progression and spherical equivalent progression were significantly different in low myopia between fast and slow progressing (P < .001), but the relationship between progression in AL/CR and progression in spherical equivalent was not strong., Conclusions: The AL/CR can be used to classify different grades of myopia, but it is not useful in determining the magnitude of myopia or monitoring progression because AL/CR is not linearly related to spherical equivalent and because progression in AL/CR is not strongly related to spherical equivalent progression.

Purpose: Patients are usually advised to wait 5 minutes between eye drops. This delay supposedly allows the first drop not to be washed out by the second one, thereby increasing the combined effect. However, in the only experimental study conducted in humans on the concurrent administration of two different eye drops, the authors concluded that a 10-minute time interval between eye drops did not increase their combined effect. Our study was designed to address this puzzling observation., Methods: Using digital photographs shot in photopic conditions in 40 eyes of 20 healthy volunteers, we compared relative pupil surface (i.e., pupil to iris surface area ratios) before and after the administration of one drop of 10% phenylephrine and one drop of 0.5% tropicamide either immediately or after a 5-minute time interval., Results: Waiting 5 minutes yielded a 5.6% relative pupil surface gain (observer 1: P = .003, observer 2: P = .005) indicating an additional combined effect with a 5-minute time interval., Conclusions: These results show a detectable additive effect that is probably the result of methodological refinements including the challenging of the mydriasis by photopic conditions and the use of pupil and iris surface areas, which may show differences that would be undetectable in terms of diameter.

Purpose: Multifocal contact lenses have been growing in popularity as a modality to correct presbyopic eyes, although visual side effects such as disability glare have been reported. The objective of this study was to investigate the effect of multifocal contact lenses on disability glare by means of ocular straylight., Methods: A prospective randomized, comparative study was performed that included 16 subjects free of ocular pathology. Straylight was measured using a commercial straylight meter with the natural and dilated pupil. Participants were fitted with Proclear Multifocal (Distance/Near), ACUVUE Oasys for Presbyopia, and Air Optix Aqua Multifocal randomized to the left or right eye. Straylight measurements were repeated with the contact lens in situ after the pupil dilation. Results obtained with the dilated pupil without contact lens acted as a control., Results: Diameter of the natural and dilated pupil was 2.87 ± 0.40 mm and 7.45 ± 0.86 mm, respectively (P < .001). After pupil dilation, straylight increased from 0.92 ± 0.13 log(s) to 1.04 ± 0.11 log(s) (P < .001). Of the four studied lenses, a significant difference was only found between Air Optix and the control group (P = .006). The latter showed also slightly increased light scatter., Conclusions: A difference in measured straylight was found between the studied multifocal lenses. The observed variability and the straylight-pupil size dependency should be taken into account to avoid elevated straylight in multifocal contact lens wearers. The reason for the observed differences in straylight must be the subject of future studies.

Purpose: To evaluate whether an induced astigmatism influences the subjective depth of focus., Methods: Fifty-one participants aged 18 to 35 years and with a mean spherical equivalent refractive error of -0.51 ± 2.35 DS participated in the study. The accommodation was blocked with three drops of 1% cyclopentolate. Refractive errors were corrected after subjective refraction with a 4-mm artificial pupil. To evaluate the depth of focus (DoF), defocus curves with a spherical range of ±1.5 DS were assessed. The DoF was calculated as the horizontal distance at a threshold level of +0.1 logMAR from the maximum visual acuity (VA). Defocus curves were estimated binocularly during distance (500 cm) and a near vision (40 cm) for two induced axis (ATR in 0° and WTR in 90°) and for a fixed amount of astigmatic defocus of -0.5 DC., Results: The mean natural DoF was 0.885 ± 0.316 D for far vision and 0.940 ± 0.400 D for near vision. With induced astigmatism, the DoF for far vision was significantly increased to 1.095 ± 0.421 D (p = 0.006, ANOVA) for the WTR astigmatism but not for the ATR astigmatism (1.030 ± 0.395 D; p = 0.164, ANOVA). The induced WTR astigmatism enhanced the DoF for near vision significantly to 1.144 ± 0.338 D (p = 0.04, ANOVA), and DoF with induced ATR astigmatism (0.953 ± 0.318 D) was not significantly different (p = 1.00, ANOVA). ATR-astigmatism reduced VA by +0.08 ± 0.08 logMAR (p < 0.01, t-test)., Conclusions: With an induced WTR astigmatism of -0.5 DC, the DoF can be enhanced in the near viewing distance with a marginal loss in binocular VA. The approach of using induced WTR astigmatism can lead to novel optical treatments for presbyopia.

Purpose: To investigate the time course of pupil centration after application of common topical ocular drugs., Methods: Single drops of 2.5% phenylephrine hydrochloride, 1% tropicamide, and 2% pilocarpine hydrochloride were applied on different days to the right eyes of 12 participants. Anterior eye images were captured, at 5-min intervals for an hour, using an infrared-sensitive camera. The images were analyzed to determine pupil diameter and pupil center, the latter with respect to the limbal center. As a control, natural pupil size and pupil center were determined under different illuminances., Results: Pupil centers of natural pupils shifted temporally as pupils dilated. At common pupil sizes, drug-induced pupil centers were different from natural pupil centers. Phenylephrine produced a center shift in the nasal and inferior directions that peaked after a mean of 30 min, whereas dilation was continuing up to 60 min. Tropicamide produced transient center shifts in the nasal and inferior directions that peaked at about 10 min before reducing toward baseline values, whereas dilation reached a peak at about 25 min. Pilocarpine produced a small sustained superior shift that, like constriction, reached a peak after about 25 min., Conclusions: Application of topical ophthalmic drugs cause shifts in pupil center that do not match those produced by natural changes in pupil size and that, in the cases of phenylephrine and tropicamide, follow a different time course than the pupil size changes.

Purpose: To determine the effect of cycloplegia on corneal thickness, corneal curvature, anterior chamber depth (ACD), angle-to-angle (ATA) and white-to-white (WTW) distances, and axial length (AL)., Methods: Changes in corneal thickness, corneal curvature, ACD, ATA and WTW distances, and AL with and without cycloplegia were analyzed in 31 eyes of 31 young myopic adults, aged 26.4 ± 3.0 years. Pentacam was used to measure the corneal thickness, corneal volume, and corneal curvatures. Visante optical coherent tomography (OCT) measured corneal thickness, ATA distance, ACD, and pupil size. The AL and WTW distance were measured using IOLMaster., Results: Cycloplegia induced significant flattening of corneal curvatures (p = 0.019, 0.001, and 0.003 for anterior sagittal, posterior tangential, and posterior sagittal curvatures, respectively). The difference in the posterior corneal curvature was greater in corneas with steeper posterior curvatures. Cycloplegia also induced significant deepening of ACD (0.08 ± 0.06, p < 0.001) and widening of both WTW (0.42 ± 0.43, p < 0.001) and ATA (0.08 ± 0.17, p = 0.015) distances. The cycloplegia-related increase in the ATA distance correlated negatively with AL (r = -0.361, p = 0.046), whereas the cycloplegia-related increase in WTW distance correlated weakly with the increase in ACD (r = 0.347, p = 0.056) but not with AL. The AL did not change with cycloplegia. Pentacam measured a slightly thicker cornea than OCT (p = 0.002). Both Pentacam and OCT detected a significant increase in corneal thickness of 4 μm, which could be attributed to reflex tearing, after cycloplegia., Conclusions: Cycloplegia resulted in deeper ACD, greater ATA distance, and flatter corneal curvatures. Surgeons should be aware of these cycloplegia-related alterations for more accurate phakic/functional intraocular lens selection and better refraction results.

Purpose: The SVOne is a portable Hartmann-Shack wavefront aberrometer that can be attached to a smartphone to determine the refractive error of the eye objectively. The aim of the present study was to compare the findings of the SVOne with retinoscopy, subjective refraction, and two commercially available autorefractors (Topcon KR-1W and Righton Retinomax-3)., Methods: Refractive error was assessed both with and without cycloplegia in 50 visually normal, young adults using the five techniques described above. Further, to assess repeatability of the instruments, the entire procedure was repeated in a subgroup of 10 subjects. All data were analyzed in terms of power vectors (M, J0, and J45)., Results: No significant difference was observed between the mean values of M (spherical equivalent) for the different techniques. However, a significantly higher mean value of precyclopegic J0 was recorded for the SVOne, which also had the highest limits of agreement for both the J0 and J45 astigmatic components. Retinoscopy and subjective refraction showed the best repeatability (in terms of M values) for precycloplegic and postcycloplegic measurements, respectively. High and significant linear correlations were observed between the subjective findings and the other four techniques., Conclusions: The results indicate that the SVOne handheld aberrometer provides measurements of refractive error in normal, young individuals that are not significantly different from other subjective and objective procedures. This instrument is valuable for vision screenings, as well as examinations taking place outside the clinical office. It may also serve as an adjunct in the standard optometric examination.

Purpose: The purpose of this study was to determine the sensitivity and specificity for detection of referable age-related macular degeneration (AMD) using an existing nonmydriatic telemedicine pathway for diabetic retinopathy screening with comparison to same-day face-to-face examination by a retina specialist., Methods: Subjects in this study underwent nonmydriatic and mydriatic digital retinal imaging on the same day as stereoscopic dilated examination of the macula by a retina specialist and the level of AMD was recorded for each eye. Images were graded by two trained readers as nonreferable or referable (AREDS [Age-Related Eye Disease Study] grading of level 3 or greater). Sensitivity and specificity were calculated by comparing referral recommendations between each reader and the retina specialist ("gold standard")., Results: There were 47 subjects (94 eyes) enrolled in the study. Sensitivity for nonreferable AMD with nonmydriatic imaging was 1.0 (reader 1) and 1.0 (reader 2), whereas specificity was 0.75 (reader 1) and 0.91 (reader 2). Sensitivity for referable AMD with nonmydriatic imaging was 0.84 (reader 1) and 0.88 (reader 2), whereas specificity was 0.81 (reader 1) and 0.81 (reader 2)., Conclusions: Our study showed that nonmydriatic digital retinal imaging had excellent sensitivity and specificity in identifying referable and nonreferable AMD using an existing validated telemedicine pathway for diabetic retinopathy screening.

Purpose: To investigate the effects of topical cyclopentolate on ocular biometry parameters in healthy young adults., Methods: Ocular biometry measurements were performed twice with 45-minute intervals by use of the IOLMaster. Effects of topical application of 1% cyclopentolate were examined in 25 eyes from 25 young adults (group 1) before and after its application. As a control (cyclopentolate-free, group 2), 30 eyes from 30 age- and sex-matched healthy subjects were evaluated within the same period., Results: There was no difference between the groups with respect to mean (±SD) ages (group 1: 23 [±3.19] years [range, 18 to 28 years] vs. group 2: 22.6 [±2.7] years [range, 18 to 28 years], p = 0.616). In group 1, the anterior chamber depth and horizontal iris width (white-to-white distance) measurements between the two sessions were significantly different, whereas the axial length was not. In group 2, none of these parameters were different between the two sessions., Conclusions: Topical application of 1% cyclopentolate caused an increase in the anterior chamber depth and white-to-white distance values without any significant effect on axial length measurement. It is necessary to consider these effects on measurements taken with an IOLMaster in young adults in whom 1% cyclopentolate has been applied.

Purpose: To compare the aberrometry-derived refractive error measurements from the IRX3 aberrometer (Imagine Eyes, Orsay, France) with a standardized measure of refractive error from the Shin-Nippon SRW-5000 (Japan) autorefractor in a large sample of school-aged children., Methods: Participants were a subgroup of children from the Northern Ireland Childhood Errors of Refraction Study phase 2 (n = 161 9 to 10 years; n = 147 15 to 16 years). Refractive error was measured under cycloplegia (1.0% cyclopentolate HCl) with the IRX3 aberrometer followed by measurement with the Shin-Nippon autorefractor. Mean differences and 95% confidence intervals and limits of agreement were calculated for refractive vector components (M, J0, and J45)., Results: Participants had a wide range of refractive error ranging from -6.00 to +8.00 diopters (D) spherical equivalent refraction. Fixed measurement biases (±95% confidence interval) between instruments were small for both groups (9- to 10-year-olds: M, -0.20 ± 0.65 D; J0, -0.005 D; J45, 0.05 D; 15- to 16-year-olds: M, 0.03 ± 0.61 D; J0, -0.04 D; J45, -0.02 D). Statistically significant differences were found between instruments for M and J45 for the 9- to 10-year-old group (p < 0.0001) and for J0 for the 15- to 16-year-old group (p = 0.003). A statistically significant proportional measurement bias was found for the cylindrical components J0 and J45 for both groups (p < 0.0001), but no statistically significant proportional bias was found for M for either group., Conclusions: This is the first study to explore refractive error measurements from the IRX3 aberrometer in children. The differences between instruments for all refractive components (M, J0, and J45) were small for both groups (<0.25 D) and may not be considered clinically meaningful. Levels of agreement were also comparable to other studies investigating the validity of instruments measuring automated refraction in both adults and children. The results would suggest that these objective techniques produce similar results for assessment of refractive error in children.

Purpose: To determine if measurement of monochromatic wavefront aberrations in near-infrared light can accurately and precisely predict subjective refractive error for polychromatic light. Our approach requires knowledge of the monochromatic wavelength-in-focus (WiF) when polychromatic light is well focused, for which new empirical measurements are reported., Methods: With accommodation paralyzed, subjective refractive error was measured as a function of wavelength using a Badal optometer by optimally focusing a letter chart illuminated with monochromatic or white light (color temperature, 4575 K). Wavelength-in-focus was determined by interpolation as that wavelength for which monochromatic refractive error matches white light refractive error. The population-based mean value of WiF, used in conjunction with the Indiana Eye model of chromatic aberration, corrected for monochromatic (842 nm) estimates of refractive error obtained from wavefront aberration measurements, predicts the absolute refractive error of individual eye for polychromatic light for comparison with empirical measurements., Results: Average WiF for eight subjects was 569 nm (SE = 3.6 nm) for a 3-mm pupil and 575 nm (SE = 3.0 nm) for an 8-mm pupil. For small (3 mm) pupils, the mean (±SD) error in predicting refractive error for white light was 0.20 (±0.05) diopters (D) (range, +0.70 to -0.46 D), and for large (>8 mm) pupils, the mean (±SD) prediction error was 0.004 (±0.12) D (range, +0.56 to -0.52 D). The population mean of prediction errors was statistically not different from zero for large pupils but was slightly hyperopic for small pupils., Conclusions: Subjective refractive error for white light can be accurately and precisely predicted objectively from monochromatic wavefront aberrations obtained for near-infrared light, but intersubject variability limits accuracy for individual subjects.

Purpose: To explore short-term refractive and ocular parameter changes and their correlations after cycloplegia with tropicamide., Methods: This study prospectively enrolled 114 right eyes of 114 participants (mean [±SD] age, 9.1 [±2.8] years). Spherical equivalent of refractive error (SER), axial length (AL), corneal curvature (CC), and anterior chamber depth (ACD) were measured before and after 30 minutes from instillation of 0.4% tropicamide. A partial optical coherence interferometry (Zeiss IOLMaster) was used for ocular parameter measurement. Refractive change and ocular parameter changes after cycloplegia and their correlations were evaluated., Results: Spherical equivalent of refractive error, AL, and ACD all positively shifted significantly at 30 minutes after application of 0.4% tropicamide (p < 0.0001 for each parameter measured). After cycloplegia, 28 eyes (24.6%) had a hyperopic shift of more than 0.25 diopters (D), 3 eyes (2.6%) had a myopic shift of more than 0.25 D, and 83 eyes (72.8%) had their SER changes within -0.25 to 0.25 D. The mean, maximum, and minimum keratometric values all decreased (p = 0.005, 0.03, and 0.05, respectively), whereas corneal astigmatism did not change significantly. The changes in AL, ACD, or mean keratometric values contributed little to the refractive changes after cycloplegia by tropicamide (p > 0.05, pr ≤ 0.01 for all values)., Conclusions: Spherical equivalent of refractive error, AL, and ACD all positively shifted after cycloplegia with tropicamide. Corneal curvature became flattened after cycloplegia with tropicamide, but the corneal astigmatism did not change significantly. Refractive changes did not correlate with changes in AL, ACD, or CC after cycloplegia with tropicamide.

Purpose: To determine the between-visit repeatability of peripheral autorefraction measurements using the Grand Seiko WAM-5500 in normal eyes., Methods: Cycloplegic autorefraction of the right eye was measured on 25 myopic young adults using a modified Grand Seiko autorefractor. Measurements were made centrally (along the line of sight) and ±20, ±30, and ±40 degrees from the line of sight in the horizontal meridian at two visits separated by 1 to 15 days. Five autorefraction measurements at each location were converted to vector space and averaged. Relative peripheral refraction (RPR) was calculated as the difference between the peripheral and central spherical equivalent. Between-visit repeatability was evaluated by plotting the difference versus the mean of the measurements at the two visits (bias) and by calculating the 95% limits of agreement (LoA)., Results: The mean (±SD) age and spherical-equivalent refractive error centrally (at visit 1) were 24.0 ± 1.3 years and -3.45 ± 1.42 diopters (D), respectively. There was no significant between-visit bias for any refractive component evaluated (M, J0, J45, and RPR) at any location measured (all p > 0.05). The 95% LoA of defocus (M) was ±0.21 D centrally and increased with increasing eccentricity to ±0.73 and ±0.88 D at 40 degrees nasally and temporally on the retina, respectively. The 95% LoA of RPR increased with increasing eccentricity to ±0.67 and ±0.82 D at 40 degrees nasally and temporally on the retina, respectively., Conclusions: In normal eyes, the repeatability of cycloplegic autorefraction was best centrally and decreased as eccentricity increased; however, repeatability in the far periphery was still better than previously reported between-visit repeatability for foveal cycloplegic subjective refraction. With clear knowledge of the repeatability of on- and off-axis cycloplegic autorefraction with the Grand Seiko, peripheral measurements can be properly interpreted in longitudinal studies.

Purpose: Atropine 1% has been used to slow the progression of myopia; however, it has not gained worldwide clinical acceptance because it results in clinically significant pupillary mydriasis and accommodative paralysis. Lower concentrations of atropine (0.5 to 0.01%) have been reported to be associated with fewer symptoms, while still controlling myopia. It is the purpose of this study to find the highest concentration of atropine that does not result in significant symptoms from pupillary dilation and accommodative paralysis., Methods: A 3 × 3 phase I clinical trial paradigm was used in 12 subjects, to determine the maximum dosage of atropine which could be prescribed without creating symptoms or clinical signs of insufficient accommodation or excessive pupillary dilation. Accommodation was measured by pushouts and pupillary dilation by photography. Prior to this study, we established the following criteria for comfort: 5D or more of residual amplitude of accommodation, less than or equal to a 3 mm pupillary difference between the eyes, and a report of minimal symptoms of near vision blur or outside photophobia., Results: Our results indicate that atropine 0.02% is the highest concentration that did not result in clinical symptoms and findings associated with higher dosages. Mean pupillary dilation was 3 mm, and mean accommodative amplitude was 8 diopters with this concentration. Further, reduction of the concentration of atropine from 0.02 to 0.01% did not seem to result in a decrease in clinical signs or symptoms associated with atropine., Conclusions: Atropine 0.02% is the highest concentration that does not produce significant clinical symptoms from accommodation paresis or pupillary dilation. This would be an appropriate starting point in evaluating a low dosage of atropine to slow myopic progression.

Purpose: To describe change in spherical equivalent (M) in a longitudinal sample of Tohono O'odham students ages 3 to 18 years and to test the hypothesis that astigmatism creates complex cues to emmetropization, resulting in increased change in M in the direction of increasing myopia and increased occurrence of myopia., Methods: Subjects were 777 Tohono O'odham Native American children on whom cycloplegic right eye autorefraction was measured on at least two study encounters between ages 3 and 18 years (first encounter prior to age 5.5 years, final encounter ≥3 years later). Regression lines were fit to individual subjects' longitudinal M data to estimate rate of change in M (regression slope, D/yr). Regression was also used to predict if a subject would be myopic (≤-0.75 D M) by age 18 years. Analysis of covariance was used to assess the relation between M slope and magnitude of baseline M and astigmatism. Chi-square analyses were used to assess the relation between predicted myopia onset and magnitude of baseline M and astigmatism., Results: Mean M slope was significantly more negative for hyperopes (M ≥ +2.00) than for myopes (M ≤ -0.75) or for subjects neither hyperopic nor myopic (NHM, M > -0.75 and < +2.00), but there was no significant difference between the myopic and NHM groups. Chi-square analysis indicated that final myopia status varied across level of baseline astigmatism. Subjects with high astigmatism were more likely to be predicted to have significant myopia by age 18 years., Conclusions: The association between greater shift in M towards myopia with age in subjects who were hyperopic at baseline is consistent with continued emmetropization in the school years. Results regarding predicted myopia development imply that degradation of image quality due to refractive astigmatism creates complex cues to emmetropization, resulting in increased occurrence of myopia.

Purpose: To determine the intertester agreement of refractive error measurements between lay and nurse screeners using the Retinomax Autorefractor and the SureSight Vision Screener., Methods: Trained lay and nurse screeners measured refractive error in 1452 preschoolers (3 to 5 years old) using the Retinomax and the SureSight in a random order for screeners and instruments. Intertester agreement between lay and nurse screeners was assessed for sphere, cylinder, and spherical equivalent (SE) using the mean difference and the 95% limits of agreement. The mean intertester difference (lay minus nurse) was compared between groups defined based on the child's age, cycloplegic refractive error, and the reading's confidence number using analysis of variance. The limits of agreement were compared between groups using the Brown-Forsythe test. Intereye correlation was accounted for in all analyses., Results: The mean intertester differences (95% limits of agreement) were -0.04 (-1.63, 1.54) diopter (D) sphere, 0.00 (-0.52, 0.51) D cylinder, and -0.04 (1.65, 1.56) D SE for the Retinomax and 0.05 (-1.48, 1.58) D sphere, 0.01 (-0.58, 0.60) D cylinder, and 0.06 (-1.45, 1.57) D SE for the SureSight. For either instrument, the mean intertester differences in sphere and SE did not differ by the child's age, cycloplegic refractive error, or the reading's confidence number. However, for both instruments, the limits of agreement were wider when eyes had significant refractive error or the reading's confidence number was below the manufacturer's recommended value., Conclusions: Among Head Start preschool children, trained lay and nurse screeners agree well in measuring refractive error using the Retinomax or the SureSight. Both instruments had similar intertester agreement in refractive error measurements independent of the child's age. Significant refractive error and a reading with low confidence number were associated with worse intertester agreement.

Purpose: The purpose of the current study was to examine the on- and off-eye optical performance of two types of soft contact lenses (hydrogel and silicone hydrogel)., Methods: The monochromatic aberrations (λ = 850 nm) of contact lenses were measured on-eye using a clinical Shack-Hartmann ocular aberrometer. In addition, we used an off-eye single-pass contact lens aberrometer (λ = 540 nm) in which the soft contact lens was placed within a wet cell. Comparison of the lower and higher order aberrations measured with these two methods required compensation for different wavelengths and knowledge of the refractive index of the contact lens materials., Results: The measured on-eye sphere and spherical aberration values were generally similar to those measured off-eye and those specified by the lens manufacturers for both types of soft contact lenses. However, there were notable differences, especially for high plus-powered lenses, which typically exhibited lower sphere power on the eye than expected from the lens specifications and from the off-eye measured powers, both of which were almost identical. Longitudinal spherical aberration varied with lens power in the hydrogel lenses, as expected from geometric optics theory. Longitudinal spherical aberration measurements on- and off-eye, however, deviated significantly from that expected of a thin lens with spherical surfaces due to surface asphericities. The difference between on- and off-eye optics can be modeled as a tear lens or as relative lens thickness changes caused by lens flexure., Conclusions: The results of the current study reveal that the major difference between the on-eye lens optics and the manufacturers' specifications is not due to lens errors but due to eye-lens interactions, which could be either lens flexure or a tear lens forming behind the soft contact lens.

Purpose: To objectively measure changes in the human ciliary muscle dimensions in vivo after instillation of topical phenylephrine, a mydriatic and vasodilating agent., Methods: A cross-sectional study of 25 healthy young adults was conducted. Measurements of pupil size, accommodation, and ciliary muscle thickness were made both before and 30 min after instillation of 1% proparacaine and 2.5% phenylephrine. Accommodation was measured in three ways: subjectively using a push-up technique and Royal Air Force (RAF) rule, and objectively using both the Grand Seiko autorefractor and PowerRefractor. Images of the temporal ciliary muscle were acquired using the Visante Anterior Segment Optical Coherence Tomographer (OCT). Ciliary muscle images were objectively analyzed using a computer-based segmentation technique., Results: Amplitude of accommodation using the push-up test was reduced by about 1 D with phenylephrine (p < 0.001). Phenylephrine did not change the accommodative response to a 4 D Badal target as measured by either autorefraction or photorefraction (p > 0.30). There was statistically significant thickening of the anterior region and thinning of the posterior region of the ciliary muscle with accommodation (p < 0.001, all locations). Phenylephrine did not affect either baseline ciliary muscle thickness or the accommodative contraction of the muscle (p > 0.09)., Conclusions: Low-dose phenylephrine does not affect ciliary muscle dimensions, ciliary muscle contractility, or accommodative response to a 4 D near target.

Purpose: To evaluate the potential influence of mydriatics on choroidal thickness measurement using enhanced depth imaging optical coherence tomography (EDI-OCT)., Methods: This was a randomized, double-blind, paired-eye study. Fifty-eight healthy eyes of 29 patients were included in this study, and one eye of each subject was designated randomly as experimental and the contralateral eye as control. A single drop of Mydrin-P (tropicamide and phenylephrine; Santen Pharmaceuticals, Japan) or a single drop of unpreserved saline was administered in the respective eyes of patients three times at 5-min intervals. Choroidal thickness (CT) was measured using EDI-OCT, and changes in CT before and after the administration of the eye drops were analyzed at the subfovea and at 0.5 mm intervals (to 3.0 mm) from the fovea at nasal, temporal, superior, and inferior locations., Results: Linear mixed-model analysis showed no significant changes in subfoveal CT after the administration of eye drops in either the mydriatics [from 313.00 ± 90.05 μm (before) to 316.34 ± 96.91 μm (after), p = 0.500] or placebo group [from 311.07 ± 96.26 μm (before) to 313.14 ± 95.46 μm (after), p = 0.248]. CT did not significantly differ within either group at other measured locations, as we moved further from the subfoveal starting point (all p > 0.05, linear mixed model). In evaluating a possible effect of mydriatics, we detected no significant difference in CT changes between the mydriatic test group and the saline placebo group at all intervals from the fovea (all p > 0.05, linear mixed model)., Conclusions: This study demonstrates that mydriatics (Mydrin-P) have no significant influence on clinical measurement of CT, as evaluated by EDI-OCT.

Purpose: The purpose was to compare subjective blur limits for cylinder and defocus., Methods: Blur was induced with a deformable, adaptive-optics mirror when either the subjects' own astigmatisms were corrected or when both astigmatisms and higher-order aberrations were corrected. Subjects were cyclopleged and had 5-mm artificial pupils. Black letter targets (0.1, 0.35, and 0.6 logMAR) were presented on white backgrounds., Results: For 10 subjects, blur limits were approximately 50% greater for cylinder than for defocus (in diopters). Although there were considerable effects of axis for individuals, overall, this was not strong, with the 0 degrees (or 180 degrees ) axis having approximately 20% greater limits than oblique axes. In a second experiment with text (equivalent in angle to N10 print at 40 cm distance), cylinder blur limits for six subjects were approximately 30% greater than those for defocus; this percentage was slightly smaller than for the three letters. Blur limits of the text were intermediate between those of 0.35- and 0.6-logMAR letters. Extensive blur limit measurements for one subject with single letters did not show expected interactions between target detail orientation and cylinder axis., Conclusions: Subjective blur limits for cylinder are 30 to 50% greater than those for defocus, with the overall influence of cylinder axis being 20%.

Purpose: Seven existing and three new image quality metrics were evaluated in terms of their effectiveness in predicting subjective cycloplegic refraction., Methods: Monochromatic wavefront aberrations (WA) were measured in 70 eyes using a Shack-Hartmann based device (Complete Ophthalmic Analysis System; Wavefront Sciences). Subjective cycloplegic spherocylindrical correction was obtained using a standard manifest refraction procedure. The dioptric amount required to optimize each metric was calculated and compared with the subjective refraction result. Metrics included monochromatic and polychromatic variants, as well as variants taking into consideration the Stiles and Crawford effect (SCE). WA measurements were performed using infrared light and converted to visible before all calculations., Results: The mean difference between subjective cycloplegic and WA-derived spherical refraction ranged from 0.17 to 0.36 diopters (D), while paraxial curvature resulted in a difference of 0.68 D. Monochromatic metrics exhibited smaller mean differences between subjective cycloplegic and objective refraction. Consideration of the SCE reduced the standard deviation (SD) of the difference between subjective and objective refraction., Conclusions: All metrics exhibited similar performance in terms of accuracy and precision. We hypothesize that errors pertaining to the conversion between infrared and visible wavelengths rather than calculation method may be the limiting factor in determining objective best focus from near infrared WA measurements.

Purpose: The purpose of this study was to assess optometric care of diabetic patients. The American Optometric Association recommends dilated eye examinations at least once a year for people with diabetes., Methods: Onsite chart reviews of 1497 diabetic patient charts were performed at a volunteer sample of Ohio-based optometric practices (n = 82). Four percent of all optometrists in the state of Ohio were surveyed. Data were collected from a 10-year period and included doctor age, membership in the Ohio Optometric Association (OOA) Diabetes Initiative, patient age, date of examinations, chief complaints, and dilation at examination. The primary outcome of the study was the frequency of dilated eye examination for diabetic patients by optometrists., Results: Optometrists dilated 85.8% of diabetic patients at their last comprehensive examination. The percentage of diabetic patients dilated by optometrists increased from 40.0% in 1994 to 91.5% in 2003. The average time since last comprehensive eye examination for diabetic patients was 1.0 +/- 1.8 (mean +/- standard deviation) years. Diabetic patients who were dilated at a comprehensive eye examination returned to care on average 0.7 years sooner than those who were not dilated. Doctor-level factors related to a higher average percentage of dilations were younger doctor age (beta = -6.1%/10 years of doctor age; 95% confidence interval [CI], -10.1 to -2.1) and membership in the OOA Diabetes Initiative (beta = 11.6%; 95% CI, 2.3 to 20.8)., Conclusions: There is variability in diabetic eye care by optometrists. However, the majority of optometrists surveyed in this study provided dilated eye examinations for their diabetic patients. Programs desiring to increase compliance to diabetic standard of care guidelines may benefit by targeting both doctors and patients.

Purpose: We investigated whether two drops of 0.5% tropicamide produced a wider pupillary dilation when compared with a single drop and saline control in subjects with dark-colored irides., Methods: Twelve young adult subjects with dark irides and who were free from ocular disease participated in the study. One eye of each subject, selected at random, was designated as experimental and the fellow eye as control. A single drop of 0.5% tropicamide was instilled in the lower cul-de-sac of each eye in turn. Immediately after, a second drop of 0.5% tropicamide was instilled in the experimental eye and a single drop of unpreserved saline into the control eye. A double-masked experimental protocol was followed. Digital images of both pupils of each subject were taken at baseline (predrug instillation) and then every 5 minutes up to 30 minutes postdrug instillation and at 40, 50, and 60 minutes. The images were subsequently viewed on a PC monitor, and pupil size was measured using a calibrated millimeter scale., Results: Pupil diameter increased as a function of time for both conditions reaching a maximum between 20 and 30 minutes after drop instillation. Pupil diameter was greater under the experimental condition compared with the control (analysis of variance p < 0.001). Pupil diameter reached at least 6 mm under both the experimental and control conditions., Conclusion: In young healthy subjects, compared with a single drop of tropicamide, two drops were associated with a greater degree of pupillary dilation on average over the 60-minute study period. However, the magnitude of the difference was small and not clinically significant. A single drop of tropicamide produced a pupillary diameter of at least 6 mm, which should be sufficient for the conduct of a thorough dilated fundus examination.

Background: The BV-1000 is a new instrument that performs binocular autorefraction and subjective refraction. The aim of the study was to evaluate the accuracy of the BV-1000 compared with subjective refraction without cycloplegia and the repeatability of the BV-1000 in subjects without cycloplegia., Methods: BV-1000 binocular autorefraction (mean of three measures) and automated subjective refraction was performed on 100 eyes and compared with practitioner subjective refraction. After BV-1000 assessment, the result was modified by the investigator in the form of a binocular addition; the practitioner was masked as to the result of the BV-1000. Repeatability was evaluated by comparing the test-retest data on 40 eyes. Refraction data were converted into Fourier component terms: mean spherical equivalent (MSE), J0, J45, and vector dioptric difference (VDD)., Results: Mean difference of MSE (BV-1000 subjective vs. practitioner) was 0.05 +/- 0.35 D (p = 0.13), whereas after binocular addition, the mean difference in MSE was -0.01 +/- 0.21 D (p = 0.67). The mean difference of MSE (BV-1000 objective vs. practitioner) was +0.10 +/- 0.37 D (p < 0.05). Mean difference in J0 and J45 was -0.03 +/- 0.12 D (p = 0.09) and -0.02 +/- 0.10 D (p = 0.06), respectively. More than 95% of cylinder powers were within +/- 0.50 D. The median VDD was 0.35 D (range, 1.38 D; interquartile range, 0.31) for comparisons of BV-1000 subjective refraction and the practitioner. A median VDD of 0.25 D (range, 1.06 D; interquartile range, 0.16) was found after binocular addition correction. There was no statistically significant difference (p = 0.73) in spherical intereye difference between BV-1000 subjective and subjective refraction. Mean spherical intereye difference (spherical balancing error) between the BV-1000 and practitioner subjective refraction was -0.02 +/- 0.24 D. Repeatability as described by the mean difference between occasions for MSE was found to be -0.06 +/- 0.19 D, -0.02 +/- 0.08 D for J0, and -0.03 +/- 0.07 D for J45., Conclusions: The subjective refraction routine within the BV-1000 improves the results of simultaneous binocular autorefraction data. The BV-1000 provides an accurate and repeatable measure of subjective refraction after binocular addition.

Purpose: Axial length is traditionally measured using A-scan ultrasound. The IOLMaster is a new instrument that uses partial coherence interferometry to measure axial length. We compared the repeatability of these techniques for both an experienced and an inexperienced observer, the agreement between the two techniques, and the effect of cycloplegia on IOLMaster measurements., Methods: Five measurements of axial length and three measurements of anterior chamber depth were taken with the IOLMaster in two sessions separated by 1 to 12 days in 20 young adults. The two examiners each took measurements, and the subject was then cyclopleged with 1% tropicamide. The IOLMaster readings were then repeated by both examiners, followed by five ultrasound readings. Repeatability was evaluated by calculating the difference between measurements from the two sessions. The mean and standard deviation of these differences was then used to determine the 95% limits of agreement (LoA) for each technique. In addition, the agreement between the IOLMaster and ultrasound was assessed, along with the effect of cycloplegia on IOLMaster readings., Results: The IOLMaster was more repeatable than ultrasound. For axial length, the 95% LoA were -0.11 to +0.07 mm, -0.06 to +0.05 mm, and -0.25 to +0.35 mm, for noncycloplegic IOLMaster, cycloplegic IOLMaster, and ultrasound, respectively. The two instruments showed modest agreement with each other (mean difference, +0.12 mm; 95% LoA, -0.39 to +0.64 mm; p > 0.0125). Cycloplegia had no significant effect on IOLMaster axial length measurements. The 95% LoA for anterior chamber depth measurement were -0.11 to +0.18 mm, -0.06 to +0.04 mm, and -0.19 to +0.21 mm, for noncycloplegic IOLMaster, cycloplegic IOLMaster, and ultrasound, respectively. The IOLMaster gave significantly longer anterior chamber depths than ultrasound (mean, +0.18 mm; 95% LoA, -0.02 to +0.37 mm; p < 0.0125), and cycloplegia produced significantly deeper anterior chamber depths using the IOLMaster (mean, +0.12 +/- 0.09 mm; 95% LoA, -0.05 to +0.29 mm; t = 6.17; p < 0.001). The experienced observer's measurements were more repeatable than the inexperienced observer's for ultrasound, but not for the IOLMaster., Conclusions: The superior repeatability of the IOLMaster suggests that it should become the standard for axial length measurement. The 95% limits of agreement for the cycloplegic measurements correspond to a change in refractive error of +/-0.12 D.

Purpose: To evaluate the accuracy of noncycloplegic autorefraction in a representative sample of school-age children in China., Methods: Refractive error was measured with an autorefractor, both before and after cycloplegia induced with cyclopentolate, in a population-based sample of 4973 children between the ages of 7 and 18 years. Spherical equivalent refractive error and astigmatism as represented by Jackson crossed-cylinders (J0 and J45) were the main outcome measures., Results: Noncycloplegic measurements of equivalent spheres were consistently more negative or less positive than those after cycloplegia, with mean +/- SD differences of -1.23 +/- 0.97 D. The differences were particularly large for hyperopic eyes (mean difference of -2.98 +/- 1.65 D for hyperopia of at least +2.00 D) while becoming progressively smaller for emmetropic eyes, and smaller yet for myopic eyes (mean difference of -0.41 +/- 0.46 D for myopia of -2.00 D or more). Increasing age was associated with increased, but clinically insignificant, differences. Little difference was found between noncycloplegic and cycloplegic measurements of astigmatism: mean J0 and J45 differences were -0.08 +/- 0.13 D and -0.01 +/- 0.09 D, respectively., Conclusions: Noncycloplegic autorefraction was found to be highly inaccurate in school-age children and, thus, not suitable for studies of refractive error or for prescription of glasses in this population.

Purpose: This study compares retinoscopy in infants using a near noncycloplegic technique, cycloplegia with tropicamide 1%, and cycloplegia with cyclopentolate 1%. The study sample included 29 healthy, nonstrabismic infants 4 to 7 months of age (mean 5.71 months)., Methods: Each study subject was examined at two separate visits an average of 2 weeks apart (mean [+/-SD] 14 +/- 9 days). The examiner completed a case history, iris color grading, confrontation tests, and noncycloplegic near retinoscopy in a dark room and then instilled a drop of topical anesthetic in each eye followed by 2 drops of cycloplegic agent separated by 5 min. Retinoscopy was performed 25 to 30 min after the first drops were instilled. The bottles were masked, and the drop administered at the first visit was randomly assigned., Results: On a scale of 0 to 4.9, the median iris grade was 4.0, which corresponds to a brown or darkly pigmented iris. All reported retinoscopy results are for the horizontal meridian of the right eye. The mean refractive error using noncycloplegic near retinoscopy was +0.94 D (+/-1.19 D). The mean refractive error was +1.81 D (+/-1.19 D) with tropicamide and +1.88 D (+/-1.45 D) with cyclopentolate. There was no statistically or clinically significant difference between the two cycloplegic measurements using different diagnostic agents (t = -0.46, p = 0.65). The mean difference between noncycloplegic and cycloplegic retinoscopy was 0.89 D (+/-0.66 D) with tropicamide (t = -6.57, p < 0.0001) and 1.04 D (+/-0.94 D) with cyclopentolate (t = -5.38, p < 0.0001; all two-sided paired t-tests). There were no serious adverse reactions with either agent, although one infant temporarily developed redder than normal cheeks after instillation of cyclopentolate., Conclusion: Our results suggest that tropicamide is as effective as cyclopentolate for the measurement of refractive error in most healthy, nonstrabismic infants.

Thirty-two children who had been refracted in early infancy were re-refracted at the age of 7 to 8 years. Refraction comprised cycloplegic retinoscopy at the mean age of 11 weeks and noncycloplegic retinoscopy and subjective examination at the mean age of 94 months. The change in spherical equivalent refraction (SER) was highly negatively correlated with the initial refraction (-0.863), demonstrating emmetropization; however, the correlation between the refractive error at age 7 to 8 years and the refractive error in infancy was much weaker (+0.225). The SER was significantly less and the astigmatism was greater in infancy in children who were myopic at age 7 to 8 years. There was, however, extensive overlap in range between the SER for the two groups and the initial SER was not a good predictor of myopia at 7 to 8 years, although it may help to identify children who are unlikely to become myopic. One hyperopic child with bilateral ptosis failed to emmetropize.

Background: Paremyd, a mydriatic formulation of 0.25% tropicamide and 1.0% hydroxyamphetamine hydrobromide provides adequate dilation for binocular indirect ophthalmoscopy in young Caucasians. We studied the clinical effectiveness of Paremyd in dilating heavily pigmented eyes by comparing its mydriatic efficacy in Blacks, Asians and Caucasians with light and dark brown irides. We also evaluated the efficacy of one drop of dapiprazole (Rev-Eyes) in reversing Paremyd-induced mydriasis in our subject sample., Methods: In a masked, randomized, controlled experimental design, several visual functions which included pupillary dilation, near visual acuity, amplitude of accommodation, ocular hyperemia, and discomfort glare were measured at 30-min intervals, for a total of 300 min, in subjects dilated with a single drop of Paremyd in each eye. Ease of binocular indirect ophthalmoscopy was also assessed. A 3-way analysis of variance was used to assess changes in these measures as function of irides color/pigmentation (designated as light or dark brown iris color), presence or absence of dapiprazole, and test time interval., Results: We found that subjects in our light brown irides group (mainly Caucasians) dilated faster than subjects in our dark brown irides group (mainly Blacks). Dapiprazole increased the speed of recovery from pupillary dilation for all subjects, but more so for those with light rather than dark brown irides. Similarly, subjects with light rather than dark brown irides recovered accommodative function more quickly. Although neither the use of dapiprazole nor the degree of iris color/pigmentation was significantly related to visual acuity or glare discomfort, there was a clear trend that these visual measures were affected to a greater degree in subjects with dark brown (primarily Blacks) rather than light brown irides. Overall, Paremyd provided adequate dilation for binocular indirect ophthalmoscopy in all subjects irrespective of iris color/pigmentation., Conclusions: Our data indicate that a single drop of Paremyd provides adequate mydriasis, without significant side effects, for routine fundus examination of all subjects, independent of iris color/pigmentation. Furthermore, a single drop of dapiprazole was effective in speeding the return of pupillary dilation in most subjects, but had no significant effect on accommodation, near visual acuity or glare discomfort. Side effects such as stinging upon instillation, conjunctival hyperemia, and a few instances of ptosis, with possible additional cost to patients, appear to lessen its overall clinical benefit.

Purpose: The selection of a cycloplegic agent depends on the desired outcome, the characteristics of the patient receiving the drug, and the associated risks. The Orinda Longitudinal Study of Myopia (OLSM) has used 1% tropicamide to assess the ocular components and cycloplegic refractions in a large cohort of predominantly Caucasian children. Although tropicamide has provided adequate cycloplegia and mydriasis for the OLSM cohort, conventional clinical wisdom and scientific investigations have suggested that tropicamide might not produce adequate cycloplegia and mydriasis for subjects with darker iris pigmentation. In this study one drop of 1% tropicamide followed by one drop of 1% cyclopentolate was used to determine their effectiveness in producing adequate cycloplegia and mydriasis for cycloplegic refraction and ocular component measurements in a group of African-American children., Methods: Nineteen children [age range 5.5 to 15.6 years, mean 8.4 years +/- (SD) 2.5 years] were tested at Family HealthCare of Alabama, Eutaw, AL. Their accommodative responses were measured using a Canon R-1 autorefractor prior to and at 30, 45, and 60 min after instillation of one drop of 0.5% proparacaine, 1% tropicamide (Mydriacyl), and 1% cyclopentolate (Cyclogyl) in both eyes. A target of 20/155 letters in a 4x4 grid positioned behind a +6.50 diopter (D) Badal lens provided accommodative stimuli of 1.00 D, 2.00 D, and 4.00 D., Results: All results are presented as mean +/-1 SD. Pupils, measured from video frames, dilated rapidly and maximally at 30 min after instillation of eye drops (7.3+/-0.5 mm) Predilation, the mean accommodative responses were 0.17+/-0.29 D for the 1.00 D stimulus, 1.01+/-0.40 D for the 2.00 D stimulus, and 2.77+/-0.74 for the 4.00 D stimulus. At 30 min after drop instillation, the responses were 0.07+/-0.14 D for the 1.00 D stimulus, 0.36+/-0.35 D for the 2.00 D stimulus, and 0.77+/-0.61 for the 4.00 D stimulus. Results were very similar at 45 and 60 min after drop instillation., Conclusions: Combining 1% tropicamide and 1% cyclopentolate was very effective in providing both cycloplegia and mydriasis adequate for ocular biometry and cycloplegic refractions 30 min after drop instillation in African-American children.

Purpose: The use of a topical anesthetic before the instillation of a mydriatic is recommended in order to enhance both the rate and magnitude of pupillary dilation. However, there is a paucity of data supporting the prior use of topical anesthetics with tropicamide, the most commonly used mydriatic agent in optometric practice. Therefore, we conducted a study to determine the clinical effect of proparacaine on tropicamide-induced pupillary dilation., Methods: We investigated the effects of prior instillation of 0.5% proparacaine (Ophthetic) on pupillary dilation with 0.5% tropicamide (Mydriacyl) using a double-blind, placebo-controlled protocol on two groups of young adult subjects. Thirty subjects, aged between 18 and 30 years, were divided into 2 groups of 15, based on whether they had light- or dark-colored irides. The pupils of both eyes of each subject were dilated with tropicamide, but only one eye, chosen at random, received proparacaine (experimental condition), whereas the other was administered a saline placebo (control condition). Pupil diameter was measured using a ruler and magnifying loupe., Results: Subjects with light-colored irides had a greater average pupil dilation than subjects with dark-colored irides. There was a small, statistically significant difference in pupil diameter between the control and experimental conditions, but only for subjects with light-colored irides. The rate of pupillary dilation to peak pupil diameter and the rate of decrease in pupil diameter after peak pupil diameter was reached did not differ between experimental conditions or subject groups., Conclusions: Although prior instillation of topical proparacaine produced a statistically significant difference in pupil diameter for subjects with light-colored irides, the result was not clinically significant. Therefore, we do not recommend the use of a topical anesthetic before tropicamide-induced mydriasis for young adult patients.

Background: Children often resist instillation of mydriatic drops for dilated fundus evaluation. As cycloplegic sprays have proven useful, this study's aim was to demonstrate efficacy of a mydriatic spray., Methods: Twenty-two healthy subjects, ages 2 to 8 years, participated in the study. All but two had dark brown irides. Subjects were given either one drop each of 1% tropicamide and 2.5% phenylephrine in each eye or one application of mydriatic spray (containing concentrations of 0.5% tropicamide and 2.5% phenylephrine) to each closed eyelid. Pupils were measured with a pupil gauge before drug delivery and every 10 min thereafter, for 40 min., Results: Repeated measures analysis of variance for the five time intervals demonstrated no significant difference between the two application methods nor in the method/time interaction, but a statistically significant increase in pupil size over time (p < 0.0005) for each method. A t-test revealed no statistically significant difference in pupil size (p > 0.05) between the two methods of drug administration at 40 min after application., Conclusions: This study suggests that use of mydriatic sprays on closed eyelids is as efficacious as use of mydriatic drops in open eyes for children.

A motorized and computer-interfaced phoropter was used to track the development of cycloplegia and recovery of accommodation over a 60-min period, after the topical application of a phenylephrine 5%-tropicamide 0.8% drug combination (Phenyltrope). Phenyltrope was introduced into the Canadian market about 2 years ago (Compendium of Pharmaceuticals and Specialties, 1987), and advertised as a fast acting cycloplegic and mydriatic drug. Here we report the results of our investigation of the depth of action and the temporal aspects of cycloplegia for this drug combination as a function of iris color. We also compare the action spectrum of Phenyltrope to that of tropicamide 1% under similar test conditions. Our results indicate that the latency for cycloplegia was shorter for tropicamide, the maximum rate of accommodative loss similar for both drugs, and the resultant cycloplegia at 20 min deeper for Phenyltrope. Recovery from induced cycloplegia was greater for tropicamide 60 min after drug administration. For both Phenyltrope and tropicamide, no significant differences in any of the parameters investigated were observed as a function of iris color. We conclude that even though Phenyltrope induced a measurably deeper cycloplegia than did tropicamide, the amount of residual accommodation present at 20 min (about 38%) is insufficient for most refractive purposes.