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Updated: Feb 7, 2026

Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Near-infrared and short-wave autofluorescence in ocular specimens
Yasuharu Oguchi1, Tetsuju Sekiryu2, Mika Takasumi3
1Department of Ophthalmology, Fukushima Medical University School of Medicine, 1 Hikariga-oka, Fukushima City, Fukushima, 960-1295, Japan. yoguchi@fmu.ac.jp.
Purpose:
To determine histopathologic characteristics of near-infrared autofluorescence (NIR-AF) and short-wave autofluorescence (SW-AF) in ocular tissue.
Study Design:
Retrospective study.
Methods:
Unstained specimens from four enucleated eyes with uveal melanoma were prepared for evaluation by fluorescence microscopy. The filter settings for SW-AF were 450-490 nm for excitation, 500-550 nm for emission and for NIR-AF 672.5-747.5 nm and 765-855 nm respectively.
Results:
Hyper-SW-AF was detected in the cornea, crystalline lens, anterior border layer of the iris, basement membrane of the iris posterior epithelium, retinal pigment epithelium (RPE), Bruch's membrane, and sclera. Hyper-NIR-AF was detected in pigmented tissues, i.e., iris anterior border layer, iris posterior epithelium, ciliary pigmented epithelium, RPE, pigmented cells in the choroid and pigmented cells in the melanoma tumoral masses. The iris anterior border layer had hyper-SW-AF and hyper-NIR-AF with low magnification. The cells on the iris surface were with hyper-SW-AF; under the iris surface cells with hyper-NIR-AF were detected with high magnification. Both hyper-SW-AF and hyper-NIR-AF were in RPE cells. Pigmented cells with hyper-NIR-AF in other uveal tissues did not have hyper-SW-AF. The pigmented cells in the melanoma tumoral masses had very weak NIR-AF.
Conclusions:
NIR-AF was seen in the ocular pigmented tissues. The only pigmented tissue with both hyper-SW-AF and hyper-NIR-AF was RPE, the combination of which might help interpret the cellular components of fundus lesions.
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