Impregnation of healthy nail tissue with optical clearing agents for improved optical coherence tomography imaging

Objectives The impact of optical tissue clearing on optical coherence tomography (OCT) for nail tissue imaging has not been investigated. This study seeks to compare the effects of an emollient and water on visualization of micromorphology and morphometric outcomes. Materials and Methods Thirty-six healthy nail plates were processed with a fractional CO(2)laser, imaged with OCT, and measured with calipers in duplicates. All samples were reassessed after 12-hour long sequential immersion in water and an emollient (Crodamol (TM) STS). OCT images were evaluated for thickness and scattering signal of the nail. Results Emollient-impregnation caused stronger scatter responses (P < .0001) and decreased nail thickness (MD 45 mu m,P < .0001) measured on OCT. Caliper-derived measurements were not affected by Crodamol (TM) (MD 11 mu m,P = .5538). Hydration increased nail thickness on OCT (MD 49 mu m,P < .0001) but reduced thickness measurements taken with calipers (MD 41 mu m,P < .0001). Emollient-impregnation improved visualization of onychocytes compared with dry (P = .0209) and hydrated samples (P < .0001), and reduced occurrence of refractive artifacts (P < .0001). Conclusion The use of an emollient for OCT imaging can enhance nail tissue visualization without significant effects on caliper measurements. Hydration of nails, in contrast with emollient-impregnation, may lead to disagreement between caliper- and OCT-measured nail thickness and should be practiced cautiously.

Automated summary

This study compared the effects of an emollient and water on nail tissue imaging using optical coherence tomography (OCT). Results showed that emollient impregnation enhanced visualization of nail tissue without affecting caliper measurements, while hydration caused disagreements between caliper- and OCT-measured nail thickness. It is recommended to practice caution when hydrating nails for imaging purposes.