Microvascular changes in the skin due to pharmacological and physiological provocations can be used as a marker for vascular function. While laser Doppler flowmetry (LDF) has been used extensively for measurement of skin microvascular responses, Laser Speckle Contrast Imaging (LSCI) and Tissue Viability Imaging (TiVi) are novel imaging techniques. TiVi measures red blood cell concentration, while LDF and LSCI measure perfusion. Therefore, the aim of this study was to compare responses to provocations in the skin using these different techniques. Changes in skin microcirculation were measured in healthy subjects during (1) iontophoresis of sodium nitroprusside (SNP) and noradrenaline (NA), (2) local heating and (3) post-occlusive reactive hyperemia (PORH) using LDF, LSCI and TiVi. Iontophoresis of SNP increased perfusion (LSCI: baseline 40.9±6.2 PU; 10-min 100±25 PU; p<0.001) and RBC concentration (TiVi: baseline 119±18; 10-min 150±41 AU; p = 0.011). No change in perfusion (LSCI) was observed after iontophoresis of NA (baseline 38.0±4.4 PU; 10-min 38.9±5.0 PU; p = 0.64), while RBC concentration decreased (TiVi: baseline 59.6±11.8 AU; 10-min 54.4±13.3 AU; p = 0.021). Local heating increased perfusion (LDF: baseline 8.8±3.6 PU; max 112±55 PU; p<0.001, LSCI: baseline 50.8±8.0 PU; max 151±22 PU; p<0.001) and RBC concentration (TiVi: baseline 49.2±32.9 AU; max 99.3±28.3 AU; p<0.001). After 5 minutes of forearm occlusion with prior exsanguination, a decrease was seen in perfusion (LDF: p = 0.027; LSCI: p<0.001) and in RBC concentration (p = 0.045). Only LSCI showed a significant decrease in perfusion after 5 minutes of occlusion without prior exsanguination (p<0.001). Coefficients of variation were lower for LSCI and TiVi compared to LDF for most responses. LSCI is more sensitive than TiVi for measuring microvascular changes during SNP-induced vasodilatation and forearm occlusion. TiVi is more sensitive to noradrenaline-induced vasoconstriction. LSCI and TiVi show lower inter-subject variability than LDF. These findings are important to consider when choosing measurement techniques for studying skin microvascular responses.

Background and aims: The prevalence of metabolic dysfunction‐associated steatotic liver disease (MASLD) has increased during the epidemic of obesity. Type 2 diabetes mellitus (T2DM) is associated with progressive MASLD. Therefore, many guidelines recommend screening for MASLD in patients with T2DM. Most studies in patients with MASLD have been conducted in specialist care. We investigated the prevalence and severity of MASLD in patients with T2DM from primary care. Methods: Patients with T2DM were prospectively included from primary care facilities to undergo transient elastography with controlled attenuation parameter and whole‐body magnetic resonance imaging (MRI) to assess liver fat, cardiac function, muscle composition, and distribution of body fat. Results: Among 308 participants, 59% had MASLD, 7% had suspected advanced fibrosis (transient elastography ≥ 10 kPa), and 1.9% had cirrhosis. The mean age was 63.9 ± 8.1 years; 37% were female, with no differences between the MASLD and the non‐MASLD groups. Participants with MASLD had greater body mass index (31.1 ± 4.4 vs. 27.4 ± 4.1 kg/m ² , p  < 0.001) and a higher prevalence of obesity (60% vs. 21%, p < 0.001). Obesity increased the risk of fibrotic MASLD eightfold, as confirmed by multivariable analysis. Participants with MASLD also had increased visceral and abdominal subcutaneous adipose tissue and muscle fat infiltration. On cardiac MRI, participants with MASLD had a lower left ventricular (LV) stroke volume index, a lower LV end‐diastolic volume index, and an increased LV concentricity. Conclusions: In this cohort of primary care patients with T2DM, 59% had MASLD, and 7% had suspected advanced fibrosis. Obesity was a strong predictor of fibrotic MASLD. MASLD was associated with alterations to the left ventricle and increased deposition of ectopic fat.

Background: Vasomotion is the spontaneous oscillation in vascular tone in the microcirculation and is believed to be a physiological mechanism facilitating the transport of blood gases and nutrients to and from tissues. So far, Laser Doppler flowmetry has constituted the gold standard for in vivo vasomotion analysis.Materials and methods: We applied vasomotion analysis to speed‐resolved perfusion, oxygen saturation, red blood cell tissue (RBC) tissue fraction, and average vessel diameter from five healthy individuals at rest measured by the newly developed Periflux 6000 EPOS system over 10 minutes. Magnitude scalogram and the time‐averaged wavelet spectra were divided into frequency intervals reflecting endothelial, neurogenic, myogenic, respiratory, and cardiac function.Results: Recurrent high‐intensity periods of the myogenic, neurogenic, and endothelial frequency intervals were found. The neurogenic activity was considerably more pronounced for the oxygen saturation, RBC tissue fraction, and vessel diameter signals, than for the perfusion signals. In a correlation analysis we found that changes in perfusion in the myogenic, neurogenic, and endothelial frequency intervals precede changes in the other signals. Furthermore, changes in average vessel diameter were in general negatively correlated to the other signals in the same frequency intervals, indicating the importance of capillary recruitment.Conclusion: We conclude that vasomotion can be observed in signals reflecting speed resolved perfusion, oxygen saturation, RBC tissue fraction, and vessel diameter. The new parameters enable new aspects of the microcirculation to be observed.

Background: Non-alcoholic fatty liver disease (NAFLD) affects 20–30% of the general adult population. NAFLD patients with type 2 diabetes mellitus (T2DM) are at an increased risk of advanced fibrosis, which puts them at risk of cardiovascular complications, hepatocellular carcinoma, or liver failure. Liver biopsy is the gold standard for assessing hepatic fibrosis. However, its utility is inherently limited. Consequently, the prevalence and characteristics of T2DM patients with advanced fibrosis are unknown. Therefore, the purpose of the current study is to evaluate the prevalence and severity of NAFLD in patients with T2DM by recruiting participants from primary care, using the latest imaging modalities, to collect a cohort of well phenotyped patients.Methods: We will prospectively recruit 400 patients with T2DM using biomarkers to assess their status. Specifically, we will evaluate liver fat content using magnetic resonance imaging (MRI); hepatic fibrosis using MR elastography and vibration-controlled transient elastography; muscle composition and body fat distribution using water-fat separated whole body MRI; and cardiac function, structure, and tissue characteristics, using cardiovascular MRI.Discussion: We expect that the study will uncover potential mechanisms of advanced hepatic fibrosis in NAFLD and T2DM and equip the clinician with better diagnostic tools for the care of T2DM patients with NAFLD.Trial registration:Clinicaltrials.gov, identifier NCT03864510. Registered 6 March 2019,https://clinicaltrials.gov/ct2/show/NCT03864510.

Background: Exudative wounds cause discomfort for patients. Introduction of a moisture sensor to dressings could facilitate change of dressings only when needed. The aim of this pilot study was to evaluate the ability of a newly developed moisture sensor to detect moisture in relation to the absorbing capacity of the dressing.Materials and Methods: In five patients, with one leg ulcer each, three dressing changes per patient were observed. Interval of dressing change was according to clinical need and healthcare professional's decision. Sensor activation, dressing weight and complications were registered. To investigate the effect of dressing on sensor activation, half of the observations were made without an extra layer of non‐woven between the dressing and sensor (Variant A), and half with (Variant B).Results: The sensor indicated time for dressing change in six out of fifteen observations. Variants A and B did not differ regarding activation or the timing of the activation.Conclusions: The addition of a moisture sensor for facilitating management of exudative wounds is promising. We recommend future larger studies evaluating the potential clinical benefits and risks of the addition of a moisture sensor. We also recommend evaluation of potential home monitoring of wounds by a moisture sensor.