J Olsen1,2, F H Birch-Johansen1,2, L Themstrup1,2, J Holmes3, G B E Jemec1,2. 1. Department of Dermatology, Zealand University Hospital, Roskilde, Denmark. 2. Health Sciences Faculty, University of Copenhagen, Copenhagen, Denmark. 3. Michelson Diagnostics Ltd, Maidstone, UK.
Abstract
BACKGROUND: Dynamic optical coherence tomography (D-OCT) is a noninvasive imaging technique providing images of the skin and detecting movement in the tissue ie, measuring blood flow. The "attenuation coefficient" describes light absorption and scattering abilities of the tissue, while the dynamic signal provides a quantitative measure of the blood flow. AIM: The study objective is to describe the dynamic changes of the skin and skin vessels during histamine release using D-OCT. METHODS: Healthy volunteers had local histamine injections in the skin and D-OCT-scans performed at 2-minute intervals to detect changes in blood flow, attenuation and clinical symptoms. RESULTS: 9/10 participants showed clinical wheals. An increase in blood flow was shown at all depths (P < .001 at 2 minutes). The highest relative increase was seen at 300 μm. The signal at 500 μm decreased to insignificant values and remained low after 4 minutes. A decrease in visualization depth of up to 32.7% as well as a significant increase in the attenuation coefficient was shown (P < .001 at 12 minutes for both tests). CONCLUSION: Dynamic optical coherence tomography is able to reliably identify changes in blood flow of histamine induced wheals. Dermal oedema reduces visualization depth and increases the attenuation coefficient.
BACKGROUND: Dynamic optical coherence tomography (D-OCT) is a noninvasive imaging technique providing images of the skin and detecting movement in the tissue ie, measuring blood flow. The "attenuation coefficient" describes light absorption and scattering abilities of the tissue, while the dynamic signal provides a quantitative measure of the blood flow. AIM: The study objective is to describe the dynamic changes of the skin and skin vessels during histamine release using D-OCT. METHODS: Healthy volunteers had local histamine injections in the skin and D-OCT-scans performed at 2-minute intervals to detect changes in blood flow, attenuation and clinical symptoms. RESULTS: 9/10 participants showed clinical wheals. An increase in blood flow was shown at all depths (P < .001 at 2 minutes). The highest relative increase was seen at 300 μm. The signal at 500 μm decreased to insignificant values and remained low after 4 minutes. A decrease in visualization depth of up to 32.7% as well as a significant increase in the attenuation coefficient was shown (P < .001 at 12 minutes for both tests). CONCLUSION: Dynamic optical coherence tomography is able to reliably identify changes in blood flow of histamine induced wheals. Dermal oedema reduces visualization depth and increases the attenuation coefficient.
Authors: Peijun Gong; Mitra Almasian; Gijs van Soest; Daniel de Bruin; Ton van Leeuwen; David Sampson; Dirk Faber Journal: J Biomed Opt Date: 2020-04 Impact factor: 3.170