1
|
Hultman M, Richter F, Larsson M, Strömberg T, Iredahl F, Fredriksson I. Robust analysis of microcirculatory flowmotion during post-occlusive reactive hyperemia. Microvasc Res 2024; 155:104715. [PMID: 39004173 DOI: 10.1016/j.mvr.2024.104715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/01/2024] [Accepted: 07/11/2024] [Indexed: 07/16/2024]
Abstract
BACKGROUND Flowmotion analysis of the microcirculatory blood flow is a method to extract information about the vessel regulatory function. It has previously shown promise when applied to measurements during a post-occlusive reactive hyperemia. However, the reperfusion peak and the following monotonic decline introduces false low frequencies that should not be interpreted as rhythmic vasomotion effect. AIM To develop and validate a robust method for flowmotion analysis of post-occlusive reactive hyperemia signals. METHOD The occlusion-induced reperfusion response contains a typical rapid increase followed by a monotonic decline to baseline. A mathematical model is proposed to detrend this transient part of the signal to enable further flowmotion analysis. The model is validated in 96 measurements on healthy volunteers. RESULTS Applying the proposed model corrects the flowmotion signal without adding any substantial new false flowmotion components. CONCLUSION Future studies should use the proposed method or equivalent when analyzing flowmotion during post-occlusive reactive hyperemia to ensure valid results.
Collapse
Affiliation(s)
- Martin Hultman
- Department of Biomedical Engineering, Linköping University, Sweden; Perimed AB, Datavägen 9A, Järfälla, Stockholm, Sweden.
| | - Freya Richter
- Primary Health Care Center, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Marcus Larsson
- Department of Biomedical Engineering, Linköping University, Sweden
| | - Tomas Strömberg
- Department of Biomedical Engineering, Linköping University, Sweden
| | - Fredrik Iredahl
- Primary Health Care Center, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Ingemar Fredriksson
- Department of Biomedical Engineering, Linköping University, Sweden; Perimed AB, Datavägen 9A, Järfälla, Stockholm, Sweden
| |
Collapse
|
2
|
Flowmotion imaging analysis of spatiotemporal variations in skin microcirculatory perfusion. Microvasc Res 2023; 146:104456. [PMID: 36403668 DOI: 10.1016/j.mvr.2022.104456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/02/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022]
|
3
|
Fredriksson I, Larsson M, Strömberg T, Iredahl F. Vasomotion analysis of speed resolved perfusion, oxygen saturation, red blood cell tissue fraction, and vessel diameter: Novel microvascular perspectives. Skin Res Technol 2021; 28:142-152. [PMID: 34758168 PMCID: PMC9907591 DOI: 10.1111/srt.13106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 08/21/2021] [Indexed: 12/17/2022]
Abstract
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.
Collapse
Affiliation(s)
- Ingemar Fredriksson
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Marcus Larsson
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Tomas Strömberg
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Fredrik Iredahl
- Department of Health, Medicine and Caring Sciences, Linköping University, Division of Community Medicine, Linköping, Sweden.,Department of Primary health care, Region Östergötland, Linköping, Sweden
| |
Collapse
|
4
|
The preliminary validation of laser Doppler flowmetry in systemic sclerosis in accordance with the OMERACT filter: A systematic review. Semin Arthritis Rheum 2020; 50:321-328. [DOI: 10.1016/j.semarthrit.2019.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 07/09/2019] [Accepted: 08/21/2019] [Indexed: 11/20/2022]
|
5
|
Low DA, Jones H, Cable NT, Alexander LM, Kenney WL. Historical reviews of the assessment of human cardiovascular function: interrogation and understanding of the control of skin blood flow. Eur J Appl Physiol 2019; 120:1-16. [PMID: 31776694 PMCID: PMC6969866 DOI: 10.1007/s00421-019-04246-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 10/19/2019] [Indexed: 02/06/2023]
Abstract
Several techniques exist for the determination of skin blood flow that have historically been used in the investigation of thermoregulatory control of skin blood flow, and more recently, in clinical assessments or as an index of global vascular function. Skin blood flow measurement techniques differ in their methodology and their strengths and limitations. To examine the historical development of techniques for assessing skin blood flow by describing the origin, basic principles, and important aspects of each procedure and to provide recommendations for best practise. Venous occlusion plethysmography was one of the earliest techniques to intermittently index a limb’s skin blood flow under conditions in which local muscle blood flow does not change. The introduction of laser Doppler flowmetry provided a method that continuously records an index of skin blood flow (red cell flux) (albeit from a relatively small skin area) that requires normalisation due to high site-to-site variability. The subsequent development of laser Doppler and laser speckle imaging techniques allows the mapping of skin blood flow from larger surface areas and the visualisation of capillary filling from the dermal plexus in two dimensions. The use of iontophoresis or intradermal microdialysis in conjunction with laser Doppler methods allows for the local delivery of pharmacological agents to interrogate the local and neural control of skin blood flow. The recent development of optical coherence tomography promises further advances in assessment of the skin circulation via three-dimensional imaging of the skin microvasculature for quantification of vessel diameter and vessel recruitment.
Collapse
Affiliation(s)
- David A Low
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK.
| | - Helen Jones
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | - N Tim Cable
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Liverpool, UK
| | - Lacy M Alexander
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
| | - W Larry Kenney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
| |
Collapse
|
6
|
El Nahid M, El Ashmaui A. The skin microcirculatory changes in the normal and hypertensive elderly. Eur Geriatr Med 2015. [DOI: 10.1016/j.eurger.2014.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Bruning RS, Kenney WL, Alexander LM. Altered skin flowmotion in hypertensive humans. Microvasc Res 2014; 97:81-7. [PMID: 24418051 DOI: 10.1016/j.mvr.2014.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 12/11/2013] [Accepted: 01/01/2014] [Indexed: 01/10/2023]
Abstract
Essential hypertensive humans exhibit attenuated cutaneous nitric oxide (NO)-dependent vasodilation. Using spectral analysis (fast Fourier transformation) we aimed to characterize the skin flowmotion contained in the laser-Doppler flowmetry recordings during local heating-induced vasodilation before and after concurrent pharmacological inhibition of nitric oxide synthase (NOS) in hypertensive and age-matched normotensive men and women. We hypothesized that hypertensive subjects would have lower total power spectral densities (PSDs), specifically in the frequency intervals associated with intrinsic endothelial and neurogenic control of the microvasculature. Furthermore, we hypothesized that NOS inhibition would attenuate the endothelial frequency interval. Laser-Doppler flowmetry recordings during local heating experiments from 18 hypertensive (MAP: 108±2mmHg) and 18 normotensive (MAP: 88±2mmHg) men and women were analyzed. Within site NO-dependent vasodilation was assessed by perfusion of a non-specific NOS inhibitor (N(G)-nitro-l-arginine methyl ester; l-NAME) through intradermal microdialysis during the heating-induced plateau in skin blood flow. Local heating-induced vasodilation increased total PSD for all frequency intervals (all p<0.001). Hypertensives had a lower total PSD (p=0.03) and absolute neurogenic frequency intervals (p<0.01) compared to the normotensives. When normalized as a percentage of total PSD, hypertensives had reduced neurogenic (p<0.001) and augmented myogenic contributions (p=0.04) to the total spectrum. NOS inhibition decreased total PSD (p<0.001) for both groups, but hypertensives exhibited lower absolute endothelial (p<0.01), neurogenic (p<0.05), and total PSD (p<0.001) frequency intervals compared to normotensives. These data suggest that essential hypertension results in altered neurogenic and NOS-dependent control of skin flowmotion and support the use of spectral analysis as a non-invasive technique to study vasoreactivity.
Collapse
Affiliation(s)
- R S Bruning
- Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802-6900, USA
| | - W L Kenney
- Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802-6900, USA
| | - L M Alexander
- Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802-6900, USA.
| |
Collapse
|
8
|
Abstract
The past 10 years have seen the publication of results from several multicentre clinical trials in primary and systemic sclerosis (SSc)-related Raynaud phenomenon. The publication of these studies has occurred as a result of new insights into the pathogenesis of Raynaud phenomenon, which are directing new treatment approaches, and increased international collaboration between clinicians and scientists. Although the pathogenesis of Raynaud phenomenon is complex, abnormalities of the blood vessel wall, of neural control mechanisms and of intravascular (circulating) factors are known to interact and contribute. Key players relevant in drug development include nitric oxide, endothelin-1, alpha adrenergic receptor activation, abnormal signal transduction in vascular smooth muscle, oxidative stress and platelet activation. The main advances in diagnosis have been a clearer understanding of autoantibodies and of abnormal nailfold capillary patterns as independent predictors of SSc, and widespread use and increased availability of capillaroscopy. The ultimate aim is to translate the advances made in the pathophysiology and early diagnosis into development of treatments to prevent and reverse digital vascular dysfunction and injury. This Review provides an update of the pathogenesis, diagnosis and treatment of Raynaud phenomenon. Current and future treatment approaches are discussed, and some key unanswered questions are highlighted.
Collapse
|
9
|
Increased finger skin vasoreactivity and stimulated vasomotion associated with simvastatin therapy in systemic sclerosis hypercholesterolemic patients. Rheumatol Int 2011; 32:3715-21. [DOI: 10.1007/s00296-011-2183-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 10/18/2011] [Indexed: 10/15/2022]
|
10
|
Grattagliano V, Iannone F, Praino E, De Zio A, Riccardi MT, Carrozzo N, Covelli M, Maggi P, Lapadula G. Digital laser doppler flowmetry may discriminate “limited” from “diffuse” systemic sclerosis. Microvasc Res 2010; 80:221-6. [DOI: 10.1016/j.mvr.2010.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 04/11/2010] [Accepted: 04/14/2010] [Indexed: 10/19/2022]
|
11
|
Cutolo M, Ferrone C, Pizzorni C, Soldano S, Seriolo B, Sulli A. Peripheral blood perfusion correlates with microvascular abnormalities in systemic sclerosis: a laser-Doppler and nailfold videocapillaroscopy study. J Rheumatol 2010; 37:1174-80. [PMID: 20436070 DOI: 10.3899/jrheum.091356] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To investigate possible correlations between fingertip blood perfusion (FBP) status, assessed by laser Doppler flowmetry (LDF), and morphological microvascular abnormalities, detected by nailfold videocapillaroscopy (NVC), in patients with systemic sclerosis (SSc). The effects on FBP of intravenous (IV) treatment with the prostacyclin analog iloprost were also investigated. METHODS Thirty-four consecutive patients with SSc and 16 healthy subjects were evaluated. LDF was performed by analyzing blood perfusion at the fingertips in both hands. Patients with SSc were distributed into the appropriate NVC pattern of microangiopathy (early, active, and late). Iloprost was administered to inpatients with SSc by 24-hour IV infusion for 7 consecutive days (4 microg/h). RESULTS FBP was significantly lower in patients with SSc (p < 0.05) compared to controls. Heating of the LDF probe at 36 degrees C induced a significant increase of FBP in all subjects (p < 0.001), but the slope of variation was significantly lower in patients with SSc compared to controls (p < 0.05). Patients with SSc showing the late NVC pattern of microangiopathy had significantly lower FBP than patients with the active and early NVC patterns (p < 0.05). A negative correlation was observed between FBP and NVC rating of the microvascular damage (p < 0.05). After iloprost treatment, a significant increase of FBP was observed in patients with SSc (p < 0.05). CONCLUSION Patients with SSc show a decreased FBP partially reversible by local skin heating. The FBP correlated negatively with the extent of nailfold microvascular damage, and IV iloprost treatment increased the FBP.
Collapse
Affiliation(s)
- Maurizio Cutolo
- Research Laboratory and Academic Unit of Clinical Rheumatology, Department of Internal Medicine, University of Genova, Viale Benedetto XV, no. 6, 16132 Genova, Italy.
| | | | | | | | | | | |
Collapse
|
12
|
Rossi M, Puccini R, Romagnoli MC, Di Maria C, Mattei P, Bernini M, Marconcini C, Santoro G. Acute and Subacute Effect of Rheopheresis on Microvascular Endothelial Function in Patients Suffering From Age-related Macular Degeneration. Ther Apher Dial 2009; 13:540-8. [DOI: 10.1111/j.1744-9987.2009.00705.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
13
|
|
14
|
Rossi M, Carpi A, Galetta F, Franzoni F, Santoro G. Skin vasomotion investigation: A useful tool for clinical evaluation of microvascular endothelial function? Biomed Pharmacother 2008; 62:541-5. [DOI: 10.1016/j.biopha.2008.07.085] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Accepted: 07/01/2008] [Indexed: 11/29/2022] Open
|