A Self-controlled Study of the Effect of Partial Spectral Absence of Visible Light on the Pupil

The Impact of Partial Visible Light Spectrum Absence on Pupil Response and Autonomic Nervous System Excitability: A Cross-Over Randomized Controlled Trial

Previous studies have shown that the spectrum of light influences myopia. LED lights with a partially absent light spectrum increase the risk of myopia progression compared to LEDs with a full spectrum, potentially mediated by the excitability of the parasympathetic nervous system. This study intends to compare pupil size and area, as well as parameters regulated by the autonomic nervous system (such as skin bioelectrical activity and heart rate), between LEDs with a full visible spectrum and LEDs with a partially absent spectrum around 470nm and 730nm. We aim to elucidate the physiological mechanism underlying the effect of light spectrum on pupil changes and myopia.

Study Overview

• Status: Not yet recruiting
• Conditions: Full Spectrum
• Intervention / Treatment: Other: full-spectrum light exposure; Other: specific spectrum absence light exposure

• Study Type: Interventional
• Enrollment (Estimated): 66
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Zeng Yangfa, Master's; Phone Number: 18922103998; Email: zengyangfa@qq.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• 1. Age 7-45 years 2. Able to wear multi-channel physiological measurement devices and cooperate with experimental procedures.

  3. Binocular? spherical power between -0.50 to -5.00 diopters, and cylinder power no more than -1.50 diopters.

  4. Voluntarily participate in this study with informed consent form signed.

Exclusion Criteria:

• 1. History of diseases affecting autonomic nervous system function, such as depression and anxiety.

  2. History of eye diseases such as strabismus, amblyopia, keratitis, and glaucoma, which are unsuitable for eye movement test.

  3. History of major systemic diseases or surgeries such as cranial surgery, myocardial infarction, or stroke.

  4. Systemic medication history that may affect autonomic nervous system function, including but not limited to antidepressants, antihistamines, anticholinergics, antipsychotics, and sedative-hypnotic drugs like diazepam or lorazepam.

  5. Use of eyedrops such as mydriatics or miotics that will affect pupil size. 6. Having difficulty in understanding and cooperating with the trial, such as those with disabilities, communication barriers, or those unable to undertake examinations.

  7. Other contradictions that the physician may consider inappropriate for enrolment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: full spectrum light group; Subjects were asked to stay in a resting state for 5 minutes in a dark room, then turn on the full-spectrum light and adapt to the light environment for 5 minutes, and then take measurements for 5 minutes. After wash-out in the dark room for 5 minutes, change the light to ordinary LED lamp and repeat the above test steps for measurement.	Other: full-spectrum light exposure; Subjects will stay in a room with full spectrum light for 5 minutes. After 5 minutes wash-out period, altenate to the other arm.
Experimental: ordinary LED light group; Subjects were asked to stay in a resting state for 5 minutes in a dark room, then turn on the ordinary LED lamp and adapt to the light environment for 5 minutes, and then take measurements for 5 minutes. After wash-out in the dark room for 5 minutes, change the light to full-spectrum light and repeat the above test steps for measurement.	Other: specific spectrum absence light exposure; Subjects will stay in a room with ordinary LED light for 5 minutes. After 5 minutes wash-out period, altenate to the other arm.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
pupil size	The pupil diameter is measured in real-time using the Eyelink Portable Duo eye tracker.	5 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Skin conductance response	Rapidly changing and short-duration skin surface potentials measured in real-time using the Biopac MP160 multi-channel physiological recorder.	5 minutes
Respiratory movement	The amplitude of respiratory movements measured in real-time using the Biopac MP160 multi-channel physiological recorder.	5 minutes
Pulse pressure waveform	The amplitude of respiratory movements measured in real-time using the Biopac MP160 multi-channel physiological recorder.	5 minutes
Spherical equivalent refraction	Measured with autorefractor and defined as the sum of spherical power and half of the cylinder power.	5 minutes
Uncorrected visual acuity	Visual acuity without refractive correction.	5 minutes
Axial length	Uncorrected visual acuity: Visual acuity without refractive correction.	5 minutes
Corneal curvature	Anterior corneal curvature measured by the Pentacam corneal topographer	5 minutes

Collaborators and Investigators

• Sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University

Study record dates

Study Major Dates

• Study Start (Estimated): July 24, 2024
• Primary Completion (Estimated): August 31, 2024
• Study Completion (Estimated): September 30, 2024

Study Registration Dates

• First Submitted: July 8, 2024
• First Submitted That Met QC Criteria: July 12, 2024
• First Posted (Actual): July 15, 2024

Study Record Updates

• Last Update Posted (Actual): July 15, 2024
• Last Update Submitted That Met QC Criteria: July 12, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: myopia,spectrum,vegetative nerve,pupil
• Other Study ID Numbers: 2024KYPJ062

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No