Laser Doppler Flowmetry in Manual Medicine Research

Abstract

Laser Doppler flowmetry (LDF) is commonly used in combination with reactivity tests to noninvasively evaluate skin sympathetic nerve activity and skin microvascular function. In manual medicine research, LDF has been used as a marker for global peripheral sympathetic nervous system function, but these results should be considered with caution because skin sympathetic nerve activity physiology is often overlooked. Another limitation of LDF in manual medicine research is the processing of LDF recordings. Two methods have been suggested: the time-domain analysis and the frequency-domain analysis. Standardization is required for data collection and processing in either domain to accurately interpret these changes in skin blood flow that occur after manual procedures. For physiologic studies using LDF, the authors recommend the use of noninvasive reactivity tests (positive controls) to evaluate the different mechanisms involved in overall skin blood flow changes and to compare the magnitude of these changes with those specifically elicited by manual procedures.

Multi‐domain analysis of microvascular flow motion dynamics in NAFLD

“…As has extensively been reported in the literature, little useful information can be gleaned from directly examining LDF signals . Consider the BF signals shown in Figure A,B recorded from skin at the forearm of two different people with and without T2DM.…”

Abnormalities in Cutaneous Microcirculation in Patients with Alzheimer’s Disease, Mild Cognitive Impairment, and Chronic Insomnia Disorder

“…For example, a study showed finger microcirculation, as detected by LDF, increases following 3 days of iloprost infusion but vanishes within 7 days in patients with systemic sclerosis, suggesting a longer lasting vasodilatory regimen remains to be established [10]. LDF has also been proposed as an indicator for sympathetic nervous system function [11][12][13][14][15]. In clinical scenarios, LDF and other tools have been used to measure microcirculation of certain diseases with abnormal neural/sympathetic modulation, such as segmental vitiligo [16][17][18] and port-wine stain [19,20], to diagnose these diseases or predict their response to treatment.…”

Cutaneous microcirculation reactivity in patients with arterial hypertension, taking into account intake of anti-hypertensive drugs

“…Currently, there is substantial evidence that microvascular changes occur very early and may play a role in their pathogenesis and progression [10]. In this context, it is impossible to ignore the modern methods of endothelial and micro-circulation assessment, such as LDF, which have a recognized clinical value [11]. The LDF method has some limitations resulting from the sensitivity of the results to various external measurement conditions, individual and local variability of blood flow in microcirculation; therefore, measurements should be standardized through the use of so-called provocation tests, most often causing local tissue hyperaemia [12].…”

“…The results of the LDF PORH study are influenced by numerous factors, including NO release, endothelium dependent hyperpolarization [14], and shear stress [15]. According to Yvonne-Tee et al, ML and TM are the most reproducible parameters of the PORH method [16], and according to Zegar-Parodi, more reproducible results are obtained on the fingertips than on the forearm [11].…”