Multispectral short-wave infrared imaging for characterization of skin fluid content independent of skin pigmentation

Multispectral short-wave infrared imaging for characterization of skin fluid content independent of skin pigmentation | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Multispectral short-wave infrared imaging for characterization of skin fluid content independent of skin pigmentation Leonid Shmuylovich, Quinlan McGrath, Anmol Jarang, Derek Bashe, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8970146/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Clinical assessment of inflammatory skin disease relies heavily on visual cues such as erythema, yet this sign is often less conspicuous in darkly pigmented skin because epidermal melanin attenuates visible reflectance and reduces lesion–background contrast. Short-wave infrared (SWIR, 1000–1700 nm) imaging probes a spectral window in which water absorption is strong and melanin absorption is weak, suggesting a pigment-insensitive approach to visualizing inflammation-associated dermal fluid. Here we develop a portable cross-polarized multispectral visible-to-SWIR imaging system and pseudocolor reconstruction method to enhance fluid contrast. In 24 healthy volunteers spanning a wide range of objectively measured pigmentation (individual typology angle ITA −46° to +45°), visible reflectance varied strongly with pigmentation, whereas SWIR reflectance was largely independent of skin tone. Following intradermal saline injection as a model of localized inflammation-associated dermal fluid, pseudocolor SWIR imaging markedly increased lesion-to-background contrast compared with co-registered color photography (∆E 50.2±16.7 vs 2.00±1.35; p=5.9×10⁻¹³) without correlation between SWIR contrast and pigmentation. In pilot subjects with acne, SWIR imaging enhanced lesion visibility across pigmentation levels and revealed clinically occult inflammation in darkly pigmented skin. These findings establish multispectral SWIR imaging as a quantitative, pigment-insensitive strategy for visualizing cutaneous inflammation. Health sciences/Diseases/Skin diseases Health sciences/Biomarkers/Diagnostic markers Multispectral imaging dermatology short-wave infrared inflammation Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SWIR1300VISNSInjection.mp4 Supplemental Video 1 SupplementalPigmentInsensitiveTissueFluidAssessment.docx Supplemental Text Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8970146","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":614702239,"identity":"bf4d1776-2207-4f93-a772-d6490ac9f063","order_by":0,"name":"Leonid 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