Comparison of two drug combinations for dilating dark irides

Low dose or very low dose phenylephrine and cyclopentolate microdrops for retinopathy of prematurity eye examinations (The Little Eye Drop Study): a randomised controlled non-inferiority trial

OBJECTIVE

To determine if very low dose (VLD, 0.5% phenylephrine, 0.1% cyclopentolate) mydriatic microdrop (approximately 7 μL) administration (up to three doses) is non-inferior to low dose (LD, 1% phenylephrine, 0.2% cyclopentolate) mydriatic microdrop administration for ophthalmologist-determined successful retinopathy of prematurity eye examination (ROPEE).

DESIGN

Multicentre, prospective, randomised controlled, non-inferiority clinical trial.

SETTING

Four neonatal intensive care units in Aotearoa, New Zealand from October 2019 to September 2021.

PATIENTS

Infants with a birth weight less than 1250 g or gestational age less than 30+6 weeks and who required a ROPEE.

INTERVENTIONS

The intervention: microdrop (approximately 7 μL) of VLD (0.5% phenylephrine and 0.1% cyclopentolate) to both eyes, or the comparison: microdrop of LD (1% phenylephrine and 0.2% cyclopentolate) to both eyes. Up to three doses could be administered.

MAIN OUTCOME MEASURES

The primary outcome measure was an ophthalmologist-determined successful ROPEE.

RESULTS

One hundred and fifty preterm infants (LD mean GA=27.4±1.8 weeks, mean birth weight=1011±290 g, VLD mean GA=27.5±1.9 weeks, mean birth weight=1049±281 g,) were randomised. Non-inferiority for successful ROPEE was demonstrated for the VLD group compared with the LD group (VLD successful ROPEE=100%, LD successful ROPEE=100%, 95% CI no continuity correction -0.05 to 0.05) and for Māori (95% CI no continuity correction -0.02 to 0.19).

CONCLUSION

VLD microdrops enable safe and effective screening for ROPEE in both Māori and non-Māori preterm infants.

TRIAL REGISTRATION NUMBER

ACTRN12619000795190.

Neutral Density Filters as a Tool for Cycloplegic Plusoptix-Photorefractor Measurements: An Explorative Study

Purpose:

The purpose of this study is to investigate the usefulness of neutral-density (ND) filters in cycloplegic-Plusoptix-photorefractor measurements.

Methods:

No-filter and ND-filter 0.04, 0.1 and 0.2 cycloplegic-Plusoptix-photorefractor measurements were made in 42 hypermetropic eyes. Sphere, cylinder, spherical equivalent (SEQ), J0, and J45 values were compared.

Results:

Mean Plusoptix-photorefractor pupil sizes were 7.7±0.68 and 7.7±0.72 mm The no-filter failure rate was 16%, with 87% in pupils >7.8 mm. Mean no-filter sphere, cylinder, SEQ, J0 and J45 values were +0.34±0.35D, -0.29±0.22D, +0.20±0.36, -0.00±0.15, and +0.02±0.11, respectively. Only ND-filter-0.04 provided 5% more successful measurements and a clinically significant alteration in the percentage of values exceeding 0.5D for sphere and SEQ (-10% and -20%), but not for cylinder (+5%). Despite the increased accuracy, 21% of the spherical outcome exceeded 0.50D. Furthermore, the single-measure-intraclass-correlation-coefficient between no-filter and ND-filter-0.04 outcome was moderate (sphere 0.78 (0.62-0.87), cylinder 0.59 (0.35-0.75), SEQ 0.68 (0.48-0.82), J0 0.73 (0.54-0.84) and J45 0.57 (0.50-0.86)) and indicated significant individual variation. Bland-Altman-analyses indicated significant bias for sphere and SEQ; p=0.038 and p=0.030.

Conclusion:

ND-filter-0.04 resulted in a larger proportion of successful measurements and an increased accuracy. However, an unacceptable percentage of inaccuracy was still present compared to retinoscopy. There could be validity issues with the ND-filter 0.04 or the baseline no-filter readings at the start. We conclude that cycloplegic Plusoptix-photorefraction, even with the use of a 0.04 ND filter, is not a suitable method for exact objective refraction purposes in children.

Pupillary Dilation in Research: More than Meets the Eye

Purpose: Pupil dilation is a commonly used procedure in vision research. While often considered a minimal risk procedure, there is the potential for significant adverse effects. Methods: Currently, there is variance in practices and protocols among researchers and institutions, perhaps due to a lack of guidelines for safe pupil dilation practices in research settings. In this perspective, we explore variables that can increase the potential for adverse effects and provide suggestions to limit their impact. Prior to dilation, an investigator can assess an individual's medical status and drug regimen when deciding upon a mydriatic agent to be used. Results: Assessing the angle through a variety of methods (i.e. penlight test, van Herick slit lamp, optical coherence tomography, gonioscopy) can also prevent inappropriate dilation of pupils with concerning anatomical features. During dilation, an investigator should look to limit the potential of infection and use caution in repeat dosing of dilation-resistant pupils. Conclusions: Post-dilation, an investigator should closely monitor eyes with elevated risk factors and improve an individual's health literacy on angle closure complications. When combined with proper informed consent processes regarding adverse effects, the aforementioned can allow for risk mitigation in studies using pupil dilation.

Diagnostic accuracy of teleretinal screening for detection of diabetic retinopathy and age-related macular degeneration: a systematic review and meta-analysis

Objective

To evaluate the diagnostic accuracy of teleretinal screening compared with face-to-face examination for detection of diabetic retinopathy (DR) and age-related macular degeneration (AMD).

Methods and analysis

This study adhered to the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA). A comprehensive search of OVID MEDLINE, EMBASE and Cochrane CENTRAL was performed from January 2010 to July 2021. QUADAS-2 tool was used to assess methodological quality and applicability of the studies. A bivariate random effects model was used to perform the meta-analysis. Referrable DR was defined as any disease severity equal to or worse than moderate non-proliferative DR or diabetic macular oedema (DMO).

Results

28 articles were included. Teleretinal screening achieved a sensitivity of 0.91 (95% CI: 0.82 to 0.96) and specificity of 0.88 (0.74 to 0.95) for any DR (13 studies, n=7207, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) low). Accuracy for referrable DR (10 studies, n=6373, GRADE moderate) was lower with a sensitivity of 0.88 (0.81 to 0.93) and specificity of 0.86 (0.79 to 0.90). After exclusion of ungradable images, the specificity for referrable DR increased to 0.95 (0.90 to 0.98), while the sensitivity remained nearly unchanged at 0.85 (0.76 to 0.91). Teleretinal screening achieved a sensitivity of 0.71 (0.49 to 0.86) and specificity of 0.88 (0.85 to 0.90) for detection of AMD (three studies, n=697, GRADE low).

Conclusion

Teleretinal screening is highly accurate for detecting any DR and DR warranting referral. Data for AMD screening is promising but warrants further investigation.

PROSPERO registration number

CRD42020191994.

Randomised controlled pilot trial comparing low dose and very low- dose microdrop administration of phenylephrine and cyclopentolate for retinopathy of prematurity eye examinations in neonates

AIMS

To determine ifVery low dose mydriatic eye microdrop regimen sufficiently dilates the pupil (above 4.1 mm) compared with the currently used low dose mydriatic eye microdrop regimen.Cardiovascular, gastrointestinal and respiratory adverse effects occur following eye drop instillation.

METHODS

Seventeen premature infants were recruited into this prospective, randomised controlled pilot trial in January 2017 to November 2018. Data were collected from the single-centre Neonatal Intensive Care Unit, Dunedin Hospital, New Zealand. The inclusion criteria were birth weight less than 1500 g or gestational age less than 31 weeks, or any premature infant requiring red reflex testing. Infants were randomised to receive either phenylephrine 1% or 0.5% and cyclopentolate 0.2% or 0.1%, 1 microdrop in both eyes. Efficacy outcome measures were pupil size at retinopathy of prematurity eye examination (ROPEE) and ophthalmologist rating of ease of screen.

RESULTS

All participants had sufficient pupillary dilation for a successful ROPEE. Ophthalmologists rated the ROPEE as easy for 90% of all examinations. Pupil dilation measurements at the time of examination, mean±SD, 4.8±0.2 (95% CI 4.5 to 5.2) mm for treatment A and 5±0.2 (95%CI 4.6 to 5.4) mm for treatment B (p=0.61). There were no statistically significant differences between the groups for safety data.

CONCLUSIONS

Very low dose microdrop administration of phenylephrine and cyclopentolate appears to be effective at sufficiently dilating the neonatal pupil for ROPEEs. Low dose and very low dose microdrop mydriatic regimens may also reduce the risk of unwanted adverse effects associated with these medicines.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (reference ACTRN12616001266459p).

Standards in Pupillography

The number of research groups studying the pupil is increasing, as is the number of publications. Consequently, new standards in pupillography are needed to formalize the methodology including recording conditions, stimulus characteristics, as well as suitable parameters of evaluation. Since the description of intrinsically photosensitive retinal ganglion cells (ipRGCs) there has been an increased interest and broader application of pupillography in ophthalmology as well as other fields including psychology and chronobiology. Color pupillography plays an important role not only in research but also in clinical observational and therapy studies like gene therapy of hereditary retinal degenerations and psychopathology. Stimuli can vary in size, brightness, duration, and wavelength. Stimulus paradigms determine whether rhodopsin-driven rod responses, opsin-driven cone responses, or melanopsin-driven ipRGC responses are primarily elicited. Background illumination, adaptation state, and instruction for the participants will furthermore influence the results. This standard recommends a minimum set of variables to be used for pupillography and specified in the publication methodologies. Initiated at the 32nd International Pupil Colloquium 2017 in Morges, Switzerland, the aim of this manuscript is to outline standards in pupillography based on current knowledge and experience of pupil experts in order to achieve greater comparability of pupillographic studies. Such standards will particularly facilitate the proper application of pupillography by researchers new to the field. First we describe general standards, followed by specific suggestions concerning the demands of different targets of pupil research: the afferent and efferent reflex arc, pharmacology, psychology, sleepiness-related research and animal studies.

Tropicamide has limited clinical effect on cycloplegia and mydriasis when combined with cyclopentolate and phenylephrine

PURPOSE

To examine the cycloplegic and mydriatic effect of tropicamide omission from a common pediatric eye drop combination.

METHODS

Consecutive children examined at the Ann & Robert H. Lurie Children's Hospital of Chicago from June 8, 2017 to September 6, 2017 were enrolled prospectively. Tropicamide, cyclopentolate, and phenylephrine (TCP) was instilled in one eye; cyclopentolate and phenylephrine (CP), in the other. Spherical equivalent, maximum pupil size, and pupillary constriction in response to photostimulation were measured before and 30 minutes after instillation using an autorefractor and pupillometer. Iris pigmentation was examined as a between-subjects variable.

RESULTS

A total of 75 children 4-11 years of age were included. Mean differences in spherical equivalent between TCP and CP were not statistically significant (P = 0.95). Significant interactions between eye drop regimen and iris pigmentation were observed for pupil size (P = 0.001) and constriction percentage (P = 0.02). Among only patients with dark irides, TCP yielded slightly larger pupils (7.70 vs 7.31 mm [P < 0.001]) that were less responsive to light (5.75% vs 8.07% [P = 0.002]). All pupils dilated to ≥6.0 mm, with equivalent proportions achieving ≥7.0 mm for TCP and CP (P = 0.18).

CONCLUSIONS

TCP and CP elicited equivalent cycloplegic effects. Mydriatic differences between the regimens, although statistically significant in dark irides, were of limited clinical magnitude, and all pupils achieved sufficient dilation for funduscopy.

Systematic review of mydriatics used for screening of retinopathy in premature infants

INTRODUCTION

Routine retinopathy of prematurity eye examinations are an important part of neonatal care, and mydriatic medicines are essential in dilating the pupil for the eye examination. There are concerns about the level of evidence for efficacy and safety of these mydriatic medicines.

OBJECTIVE

This review evaluates both efficacy and safety evidence of mydriatics used during the retinopathy of prematurity eye examination.

METHOD

Systematic literature review.

RESULTS

There is limited evidence guiding clinical practice for safety and efficacy of mydriatics. The majority of publications are underpowered and with an unclear to high level of bias. There are a wide variety of mydriatic regimens evaluated for efficacy and safety, and multiple regimens are associated with case reports.

CONCLUSIONS

Current international guideline seems unnecessarily high, especially when the reviewed literature suggest that lower doses are effective, albiet from underpowered studies. The lowest effective combination regimen appears to be phenylephrine 1% and cyclopentolate 0.2% (1 drop). Microdrop administration of this regimen would further increase the safety profile, however, efficacy needs to be assessed.

The ipRGC-driven pupil response with light exposure and refractive error in children

PURPOSE

The intrinsically photosensitive retinal ganglion cells (ipRGCs) signal environmental light, control pupil size and entrain circadian rhythm. There is speculation that ipRGCs may be involved in the protective effects of light exposure in myopia. Here, the ipRGC-driven pupil response was evaluated in children and examined with light exposure and refractive error.

METHODS

Children ages 5-15 years participated. Subjects wore an actigraph device prior to the lab visit for objective measures of light exposure and sleep. For pupillometry, the left eye was dilated and presented with stimuli, and the consensual pupil response was measured in the right eye. Pupil measurements were preceded by 5 min dark adaptation. In Experiment 1 (n = 14), 1 s long wavelength light ('red,' 651 nm, 167 cd m^-2 ) and 10 increasing intensities of 1 s short wavelength light ('blue,' 456 nm, 0.167-167 cd m^-2 ) were presented with a 60 s interstimulus interval. A piecewise two-segment regression was fit to the stimulus response function to determine the functional melanopsin threshold. Pupil responses were analysed with light exposure over the previous 24 h. For Experiment 2 (n = 42), three 1 s red and three 1 s blue alternating stimuli were presented with a 60 s interstimulus interval. Following an additional 5-min dark adaption, the experiment was repeated. Pupil metrics included peak constriction, the 6 s and 30 s post-illumination response (PIPR), early and late area under the curve (AUC). Following pupil measurements, cycloplegic refractive error and axial length were measured.

RESULTS

For Experiment 1, PIPR metrics demonstrated a graded response to increasing intensity blue stimuli, with a mean functional melanopsin threshold of 6.2 ± 4.5 cd m^-2 (range: 0.84-16.7 cd m^-2 ). The 6 s PIPR and early AUC were associated with 24-h light exposure for high intensity stimuli (33.3 and 83.3 cd m^-2 , p < 0.005 for both). For Experiment 2, there were no associations between pupil metrics and refractive error. The 6 s PIPR and early AUC to blue stimuli were significantly increased for Trial 2 compared to Trial 1.

CONCLUSIONS

The ipRGC-driven pupil responses in children were robust and similar to responses previously measured in an adult population. The 6 s PIPR and early AUC to high intensity blue stimuli were associated with previous light exposure. There were no associations between the ipRGC-driven pupil response and refractive status in this cohort.

Efficacy of 1% atropine eye drops in retarding progressive axial myopia in Indian eyes

Purpose:

The aim of this study is to assess the efficacy of 1% atropine eye drops for the retardation of progressive axial myopia in Indian eyes.

Methods:

This prospective interventional cohort study included children aged 5–16 years. Both the eyes of myopic children with progressive increase of ≥−0.5D sphere/year with the best-corrected vision of ≥6/6 were treated with once a day application of 1% atropine eye drops and progressive addition photogray lenses. The progression of myopia after 1-year follow-up was analyzed.

Results:

Sixty eyes of thirty myopes were included in the study. The mean age was 10 years and 15 were girls. The mean baseline sphere was −5.2D (−2.5D–−13D). Mean duration of follow-up was 23 months (12–36 months). The baseline rate of progression was reduced from −0.6D/year (range −0.5D/year to −3D/year) to −0.2D/year (range 0D/year to −1.5D/year) after atropine therapy. Seventeen patients (57%) had to use the atropine in the daytime to reach the target progression of <−0.5D/year. There was no difference between the efficacy of atropine drops in the boys and girls (P = 0.6). The efficacy of atropine drops did not have a correlation with the age of the patients or the magnitude of baseline myopia (Pearson's r = 0).

Conclusion:

1% atropine eye drops was well tolerated and efficacious for the retardation of progressive myopia in Indian eyes. Effectiveness was better with daytime application. Further studies are necessary to assess the role of 1% atropine in the rapid progressors and patients poorly responding to low-dose atropine.