Absolute quantification (ml blood/sec ∗ mm2 tissue) of normal vs. diabetic foot skin microvascular blood perfusion: Feasibility of FM-PPG measurements under clinical conditions

Publication date: Available online 24 December 2018Source: Microvascular ResearchAuthor(s): R.W. Flower, Z. Mirza, S.R. ThomAbstractFluorescence-mediated photoplethysmography (FM-PPG) is the first routine clinical methodology by which to quantifiably measure tissue blood perfusion in absolute terms (mL blood/sec ∗ mm2 tissue). The FM-PPG methodology has been described in detail previously in this journal (MVR 114, 2017, 92-100), along with initial proof-of-concept measurements of blood perfusion in both ocular and forearm skin tissues. The motivation for the current study was to investigate whether FM-PPG can be used readily and routinely under realistic clinical conditions. The vehicle for doing this was to measure medial foot capillary blood flow, i.e., tissue perfusion, in 7 normal subjects, mean = 6.76 ± 2.29 E-005 mL/(sec ∙ mm2), and lesion-free areas of 8 type-2 diabetic patients with skin ulceration, mean = 4.67 + 3.15 E-005 mL/(sec ∙ mm2). Thus, perfusion in the diabetics was found to be moderately lower than that in the normal control subjects. Earlier skin perfusion measurements in medial forearms of 4 normal subjects, mean = 2.64 + 0.22 E-005 mL/(sec ∙ mm2), were lower than both the normal and diabetic foot perfusion measurements. Variability in the heartbeat-to-heartbeat blood perfusion pulses in the skin capillaries, defined as the ratio of the standard deviation among beat-to-beat pulses divided by the mean ...
Source: Microvascular Research - Category: Biochemistry Source Type: research