Optimization of a Photoretinoscopy Method for Determining the Objective Refraction of Children

Optimization of a Photoretinoscopy Method for Determining the Objective Refraction of Children With a Smartphone/add-on Device in Hong-Kong

The objective is to compare the refractive parameters of the photorefraction prototype device without cycloplegia with the refractive parameters of reference device, an autorefractometer with and without cycloplegia.

Study Overview

• Status: Completed
• Conditions: Ametropia
• Intervention / Treatment: Device: Comparator device, Closed-field autorefractometer

Detailed Description

A single visit will be necessary. After informed consent, and checking of the inclusion and exclusion criteria, investigators will perform measurements with an autorefractometer and with the photorefraction prototype device without cycloplegia followed by an objective refraction with an autorefractometer under cyclopegia.

• Study Type: Interventional
• Enrollment (Actual): 121
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Hong Kong Polytechnic University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Voluntary, willing to follow the protocol, able to read and understand the information form and give free and informed consent (for parents/guardian of children subjects) and assent (for subjects aged 6-12 years old)
• At least 6 years old and up to 12 years old at time of informed consent and assent
• Average of the equivalent sphere(Sph+Cyl/2) of both eye included in the interval [-10.00, +0.75]
• Cylindrical refractive error between 0 and 4.00 D on both eyes
• Corrected binocular visual acuity in distance vision at least 6/9

Exclusion Criteria:

• Incapable of expressing consent
• All categories of persons particularly protected by law
• Subject in another study which might have an influence on vision or interfere with study assessment
• Less than 6 years old, or 13 years old or above at time of informed consent and assent
• Amblyopia, Cataract, Strabismus.
• Aphakic or pseudophakic (intraocular implant)
• Reported severe eye disease involving loss of visual field as in glaucoma, involving loss of acuity and severe discomfort in low or overly bright environments as in retinitis pigmentosa or reported and treated dry eye.
• Self-reported neurological deficits, including a history of epileptic pathology or sensory-motor coordination disorders, vestibular or cerebellar pathology (e.g., balance disorders, nystagmus)
• Any previous ocular surgery, which might have an influence on vision or interfere with study assessments (e.g. iridectomy, refractive surgery…),
• Any myopia control solutions that could affect refractive status of the eye (e.g. Atropine eye drops, Orthokeratology)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Photorefraction prototype device; - Photoretinoscopic images without cycloplegia	Device: Comparator device, Closed-field autorefractometer; Objective refraction without cycloplegia; Distance visual acuity with objective refraction without cycloplegia; Objective refraction with cycloplegia; Distance visual acuity with objective refraction with cycloplegia

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective refractive error	The refractive error is collected in sphere power (D), cylinder power (D) and cylinder axis (°) and converted in equivalent sphere, J0, J45 (power vector in D)	One day (all measurements are taken during the single visit)

Collaborators and Investigators

• Sponsor: Essilor International
• Investigators: Principal Investigator: Andrew KC Lam, PhD, Hong Kong Polytechnic University, School of Optometry

Study record dates

Study Major Dates

• Study Start (Actual): March 28, 2024
• Primary Completion (Actual): August 23, 2024
• Study Completion (Actual): August 23, 2024

Study Registration Dates

• First Submitted: February 22, 2024
• First Submitted That Met QC Criteria: February 28, 2024
• First Posted (Actual): March 6, 2024

Study Record Updates

• Last Update Posted (Actual): April 2, 2025
• Last Update Submitted That Met QC Criteria: March 28, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors
• Other Study ID Numbers: WS10363

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No