Multimodal Optical Coherence Tomography: Imaging of Blood and Lymphatic Vessels of the Vulva

Abstract

The aim of the study was to test the method of optical coherence tomography (OCT) for its ability to obtain images of blood and lymphatic vessels of the vulva.Materials and Methods. The study was performed using a multimodal optical coherence tomography device developed in the Institute of Applied Physics of the Russian Academy of Sciences (Nizhny Novgorod). In this setup, 3D images of 3.4×3.4×1.25 mm are created within 26 s. OCT angiography and OCT lymphangiography are based on the speckle structure analysis. Visualization of blood and lymphatic vessels does not require any additional contrast agents.A histological study of vulvar biopsy samples from two locations was performed in 3 patients without vulvar pathology and in 5 patients with vulvar lichen sclerosus; the results were then compared with 3D OCT images obtained at the same locations.Results. Using the multimodal OCT, we found that normal mucous membrane of the vulva had a well-developed network of blood and lymphatic vessels; their diameters were increasing with depth. In the subepithelial zone, only blood capillary loops could be seen, whereas lymphatic capillaries became detectable starting from a depth of 170 μm (submucosa layer).In the case of vulvar lichen sclerosus, the density of the blood vessel network decreases dramatically and the capillary loops in the subepithelial zone disappear. Lymphatic vessels become detectable at a depth of 300 μm, and only few thin vessels can be detected at depths of 300 to 600 μm. The results suggest that the presentation of blood and lymphatic vessels depends on the state of the vulvar connective tissue. Specifically, the number of blood and lymphatic vessels is reduced in areas of hyalinosis and sclerosis of collagen fibers.Conclusion. For the first time, using multimodal OCT, an in vivo study of blood and lymphatic vessels of the vulvar mucosa was performed on normal and lichen sclerosus-affected vulva; the obtained OCT images were then compared with histological images of the same tissues. The OCT method allows one to diagnose a zone of hyalinosis and sclerosis of collagen fibers characterized by an abnormally low number of blood and lymphatic vessels.

Dermatoscopy and Optical Coherence Tomography in Vulvar High-Grade Squamous Intraepithelial Lesions and Lichen Sclerosus: A Prospective Observational Trial

“… 20 , 21 These stiff vessels translated into the observed increase in blood flow in lesional LS vulvar skin, as measured by D-OCT. We hypothesize that this could be the result of sclerosis and damage to the connective tissue in LS, affecting the microvasculature of the dermis. 29 The observed increase in dermal blood flow in genital LS has not previously been objectified by D-OCT, but are in agreement with previous descriptions using laser Doppler and in 3 patients with extragenital LS. 30 , 31 Histologically, the vulvar epidermis in LS is thinner compared with healthy vulvar skin.…”

“…These newly described dermatoscopic thick and thin arborizing vessels concur with established histological features of hyalinized, stiff vessels in the dermis of LS 20,21 . These stiff vessels translated into the observed increase in blood flow in lesional LS vulvar skin, as measured by D-OCT. We hypothesize that this could be the result of sclerosis and damage to the connective tissue in LS, affecting the microvasculature of the dermis 29 . The observed increase in dermal blood flow in genital LS has not previously been objectified by D-OCT, but are in agreement with previous descriptions using laser Doppler and in 3 patients with extragenital LS 30,31 .…”

Cross-Polarization Optical Coherence Tomography for Clinical Evaluation of Dermal Lesion Degrees in Vulvar Lichen Sclerosus

“…In 2021, a group of researchers from King’s College London showed OCT effectiveness for assessing inflammatory skin diseases [ 11 ], but VLS was not studied. Our group successfully demonstrated earlier OCT application for non-invasive diagnostics of blood and lymphatic vessels state in VLS [ 12 ]. We use cross-polarization OCT (CP OCT) method in this study to identify non-invasively OCT signs of dermal lesion four degrees in VLS.…”