Depth‐resolved method for attenuation coefficient calculation from optical coherence tomography data for improved biological structure visualization

Abstract

Optical coherence tomography (OCT) is a promising tool for intraoperative tissue morphology determination. Several studies suggest that attenuation coefficient derived from the OCT images, can differentiate between tissues of different morphology, such as normal and pathological structures of the brain, skin and other tissues. In the present study, the depth‐resolved method for attenuation coefficient calculation was adopted for the real‐world situation of the depth‐dependent OCT sensitivity and additive imaging noise with non‐zero mean. It was shown that in the case of sharp focusing (~10 μm spot full width at half maximum (FWHM) or smaller at 1.3 μm central wavelength) only the proposed method for depth‐dependent sensitivity compensation does not introduce misleading artifacts into the calculated attenuation coefficient distribution. At the same time, the scanning beam focus spot with FWHM greater than 10 μm at 1.3 μm central wavelength allows one to use multiple approaches to the attenuation coefficient calculation without introducing noticeable bias. This feature may hinder the need for robust corrections for the depth‐resolved attenuation coefficient estimations from the community.This article is protected by copyright. All rights reserved.

Multimodal OCT Control for Early Histological Signs of Vulvar Lichen Sclerosus Recurrence after Systemic PDT: Pilot Study

“…In our study, the most informative parameter reflecting the recovery of vulvar tissue in the early stages of observation (1–3 months) is the depth-resolved attenuation coefficient, which was calculated using the authors’ original algorithm aimed at improving the visualization of biological tissue structures [ 43 ]. The attenuation coefficient is a complex parameter that reflects the absorption and scattering of probing radiation in the tissue [ 40 ].…”

“…In a previous paper, we described similar changes in collagen bundles in the early stages of VLS using multiphoton microscopy [ 35 ]. It is important to note that in the described publications on the use of the attenuation coefficient to assess the effectiveness of PDT [ 44 , 45 ], the attenuation coefficient was calculated using log- and linear-fit methods, which visualize tissue structures to a lesser extent than the coefficient calculated using our depth-resolved method with additive noise and OCT sensitivity compensation [ 43 ].…”

“…To calculate the OCT attenuation coefficient, a backscattering OCT signal was used, and the depth-resolved method proposed by K. Vermeer was applied [ 67 ]. This method was modified by our group to compensate for additive noise [ 68 ] and sensitivity of the OCT device, which depends on the scanning depth [ 43 ]. This avoids the systematic error in estimating the attenuation coefficient, which is characteristic of the K. Vermeer method.…”