Effect of short-wavelength light on subfoveal choroidal thickness with induced hyperopic defocus in young adult emmetropes Original research study

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Published: Oct 6, 2026
DOI: https://doi.org/10.24292/01.OT.241926
Keywords:
hyperopic defocus, subfoveal choroidal thickness, shorter wavelength

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Zahra Batool
Outpatient Department, Al-Shifa Trust Eye Hospital, Rawalpindi
Saif Ullah
Optometry Department, Pakistan Institute of Ophthalmology, Al-Shifa Trust Eye Hospital, Rawalpindi
http://orcid.org/0000-0003-3254-5585
Amtul Aziz
Diagnostic Department, Al-Shifa Trust Eye Hospital, Rawalpindi
Fatima Yousaf
Diagnostic Department, Al-Shifa Trust Eye Hospital, Rawalpindi
Mehmona Asgher
Optometry Department, Pakistan Institute of Ophthalmology, Al-Shifa Trust Eye Hospital, Rawalpindi
http://orcid.org/0000-0003-1265-1137
Muqadas Shahzadi
Cornea Department, Al-Shifa Trust Eye Hospital, Rawalpindi

Abstract

Purpose: This study aimed to investigate the effect of short term exposure to shorter wavelengths and induced hyperopic defocus on subfoveal choroidal thickness (SFCT).
Materials and methods: A pre- and post-quasi experimental study was conducted in the diagnostic department of a tertiary eye care hospital using judgmental sampling technique. Visual acuity and refractive status were measured using logMAR and a Retinoscope. Dual exposure included 405 nm laser for 60, 120, and 180 s, and an android phone in blue mode for 2 h with hyperopic defocus. Subfoveal choroidal thickness was measured with OPTOVUE AVANTI spectral domain-optical coherence tomography (SD-OCT). Data entry and analysis were done with JAMOVI.
Results: The study included 30 subjects with a mean age of 20.67 (±0.96) years, ranging from 19 to 23 years. In terms of SFCT measurements before and after defocus at various intervals of blue light exposure, significant changes were observed. The mean pre-defocus subfoveal choroidal thickness (PDSFCT) was 298.23 (±45.44) μm, increasing to 320.53 (±51.89) μm after defocus (ADSFCT). This change was statistically significant, as indicated by a paired sample t-test (t = -4.805, p <0.001) after 2 h of android phone in full blue mode with hyperopic defocus. Similarly, significant differences were noted at 60 sec. (t = -3.796, p <0.001), 120 s (t = -2.013, p = 0.027), and 180 s (t = -2.028, p = 0.026) of blue light exposure.
Conclusion: Exposure to shorter wavelengths induces an increase in subfoveal choroidal thickness that is independent of defocus.

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How to Cite
1.
Batool Z, Ullah S, Aziz A, Yousaf F, Asgher M, Shahzadi M. Effect of short-wavelength light on subfoveal choroidal thickness with induced hyperopic defocus in young adult emmetropes. Ophthatherapy [Internet]. 2026Oct.6 [cited 2026Oct.23];00:A241926. Available from: https://www.journalsmededu.pl/index.php/ophthatherapy/article/view/3409
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Diagnostics
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