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

Not Applicable

Not yet recruiting

• Conditions: Full Spectrum
• Interventions: Other: full-spectrum light exposure; Other: specific spectrum absence light exposure

• Registration Number: NCT06501131
• Lead Sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Status Verified: 2024-07
• Study First Submitted: 2024-07-08
• Study First Submitted QC: 2024-07-12
• Last Update Submitted: 2024-07-12
• Study First Posted: 2024-07-15
• Last Update Posted: 2024-07-15
• Study Start: 2024-07-24
• Primary Completion: 2024-08-31
• Study Completion: 2024-09-30

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 66

Inclusion Criteria

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

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

  3. 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.

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
full spectrum light group	full-spectrum light exposure	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.
ordinary LED light group	specific spectrum absence light exposure	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.

Primary Outcome Measures

Name	Time	Method
pupil size	5 minutes	The pupil diameter is measured in real-time using the Eyelink Portable Duo eye tracker.

Secondary Outcome Measures

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