Characterizing the microcirculation of atopic dermatitis using angiographic optical coherence tomography

Abstract

Background and Aim: With inflammatory skin conditions such as atopic dermatitis (AD), epidermal thickness is mediated by both pathological hyperplasia and atrophy such as that resulting from corticosteroid treatment. Such changes are likely to influence the depth and shape of the underlying microcirculation. Optical coherence tomography (OCT) provides a non-invasive view into the tissue, however structural measures of epidermal thickness are made challenging due to the lack of a delineated dermal-epidermal junction in AD patients. Instead, angiographic extensions to OCT may allow for direct measurement of vascular depth, potentially presenting a more robust method of estimating the degree of epidermal thickening.Methods and results: To investigate microcirculatory changes within AD patients, volumes of angiographic OCT data were collected from 5 healthy volunteers and compared to that of 5 AD patients. Test sites included the cubital and popliteal fossa, which are commonly affected by AD. Measurements of the capillary loop and superficial arteriolar plexus (SAP) depth were acquired and used to estimate the lower and upper bounds of the undulating basement membrane of the dermal-epidermal junction. Furthermore, quantitative parameters such as vessel density and diameter were derived from each dataset and compared between groups. Capillary loop depth increased slightly for AD patients at the poplitial fossa and SAP was found to be measurably deeper in AD patients at both sites, likely due to localized epidermal hyperplasia.Conclusions: Quantifying subtle changes within vascular morphology and depth may give clinicians an indication of the subsurface abnormalities at both involved and uninvolved AD sites.

Sub-clinical assessment of atopic dermatitis severity using angiographic optical coherence tomography

“…Previously we have shown that measurable morphological differences between healthy and AD scans are attainable using svOCT depth projections over a wide depth range (30-300μm) [32], however it is unclear if the differences were related to true morphological differences or simply a result of the AD vessels being much deeper in the skin. To investigate this, the SPD data from Sec.…”

“…1, the capillary loop depth (CLD) and superficial plexus depth (SPD) within skin could potentially be used as a robust measure of acanthosis (epidermal hypertrophy). In our previous work, measurements of CLD and SPD were acquired qualitatively through visual observation of an en-face flythrough of the corresponding angiographic data [32]. Here, the skeletonization procedure outlined in Sec.…”

Dynamic Optical Coherence Tomography Is a New Technique for Imaging Skin Around Lower Extremity Wounds

“…Optical coherence tomography (OCT) is gaining acceptance as a useful device to aid in the diagnosis of basal cell carcinoma, as well as for research into many skin conditions and their treatments. [9][10][11][12][13][14] OCT was first described by Huang and coworkers at Massachusetts Institute of Technology (MIT) in 1991 and has been very successfully applied to the field of ophthalmology for imaging the subsurface structures of the retina and other avascular parts of the eye. 15 Welzel et al reported the use of OCT to obtain structural images of the most superficial layers skin.…”

Reflectance Confocal Microscopy, Optical Coherence Tomography, and Multiphoton Microscopy in Inflammatory Skin Disease Diagnosis

“…AD was studied with OCT in two studies [47,48]. In patients with known AD, acanthosis was assessed by measurements of superficial plexus depth in patients with healed flares.…”

“… Epidermal spongiosis, lymphocyte exocytosis, stratum corneum disruption, and parakeratosis are characteristic of contact dermatitis in RCM and OCT [15,37‐46,68]. Acanthosis, thickened epidermis, and dilated blood vessels are associated with AD using angiographic OCT and MPM [47‐51]. Perinuclear mitochondria and spongiosis are also observed using MPM only [49‐51].…”