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Nickerson DS, Yamasaki DS. Objective Evidence That Nerve Decompression Surgery Reduces Neuropathic DFU Recurrence Risk to Less than 5%. Adv Wound Care (New Rochelle) 2024. [PMID: 38511527 DOI: 10.1089/wound.2023.0199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024] Open
Abstract
Significance: Despite 20 years of research and new treatment methods, diabetic foot ulcer (DFU) remains a common problem with frequent recurrences and complications. Recent Advances: There are reports that nerve decompression (ND) surgery has been observed to produce significantly fewer DFU recurrences than standard of care (SOC). The explanation of this apparent superiority has not been understood. Critical Issues: Microcirculation is understood to be involved in diabetic peripheral neuropathy (DPN) and DFU. There is an underappreciation of the participation in DPN of entrapment neuropathy (EN) due to nerve swelling and impingement in fibro-osseous tunnels. Reducing c-fiber compression in EN by ND generates recovery of subepidermal capillary flow. ND studies have found improved neuromuscular function and epidermal microcirculation phenomena, including chronic capillary ischemia (CCI) and pressure-induced vasodilatation (PIV). There is no current therapy recommended for impaired microcirculation. Clinical and animal evidence has demonstrated that release of locally compressed peripheral nerves improves the epidermal microcirculation which is under sympathetic control. Future Directions: Using epineurolysis to relieve nerve compressions is a physiology-based therapeutic intervention and provides the scientific foundation clarifying how ND reduces DFU recurrence risk. Incorporating ND with current SOC treatments could improve DFU recurrence risk, hard-to-heal ulcers, neuroischemic wounds, amputation risk, and the resulting costs to society. More studies using ND for DFU, especially evidence-based medicine Level I studies, are needed to confirm these preliminary outcomes.
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Versteeg N, Wellauer V, Wittenwiler S, Aerenhouts D, Clarys P, Clijsen R. Short-term cutaneous vasodilatory and thermosensory effects of topical methyl salicylate. Front Physiol 2024; 15:1347196. [PMID: 38706945 PMCID: PMC11066213 DOI: 10.3389/fphys.2024.1347196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/21/2024] [Indexed: 05/07/2024] Open
Abstract
Introduction Methyl salicylate, the main compound of wintergreen oil, is widely used in topical applications. However, its vascular and thermosensory effects are not fully understood. The primary aim was to investigate the effects of topical methyl salicylate on skin temperature (Tskin), skin microcirculation (MCskin) and muscle oxygen saturation (SmO2) compared to a placebo gel. The secondary aim was to assess thermosensory responses (thermal sensation, thermal comfort) and to explore to which extent these sensations correspond to the physiological responses over time. Methods 21 healthy women (22.2 ± 2.9 years) participated in this single-blind, randomized controlled trial. Custom-made natural wintergreen oil (12.9%), containing methyl salicylate (>99%) and a placebo gel, 1 g each, were applied simultaneously to two paravertebral skin areas (5 cm × 10 cm, Th4-Th7). Tskin (infrared thermal imaging), MCskin (laser speckle contrast imaging) and SmO2 (deep tissue oxygenation monitoring) and thermosensation (Likert scales) were assessed at baseline (BL) and at 5-min intervals during a 45 min post-application period (T0-T45). Results Both gels caused an initial decrease in Tskin, with Tskin(min) at T5 for both methyl salicylate (BL-T5: Δ-3.36°C) and placebo (BL-T5: Δ-3.90°C), followed by a gradual increase (p < .001). Methyl salicylate gel resulted in significantly higher Tskin than placebo between T5 and T40 (p < .05). For methyl salicylate, MCskin increased, with MCskin(max) at T5 (BL-T5: Δ88.7%). For placebo, MCskin decreased (BL-T5: Δ-17.5%), with significantly lower values compared to methyl salicylate between T0 and T45 (p < .05). Both gels had minimal effects on SmO2, with no significant differences between methyl salicylate and placebo (p > .05). Thermal sensation responses to topical methyl salicylate ranged from "cool" to "hot", with more intense sensations reported at T5. Discussion The findings indicate that topical methyl salicylate induces short-term cutaneous vasodilation, but it may not enhance skeletal muscle blood flow. This study highlights the complex sensory responses to its application, which may be based on the short-term modulation of thermosensitive transient receptor potential channels.
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Affiliation(s)
- Ninja Versteeg
- Rehabilitation and Exercise Science Laboratory (RESlab), Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland
| | - Vanessa Wellauer
- Rehabilitation and Exercise Science Laboratory (RESlab), Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland
| | - Selina Wittenwiler
- Rehabilitation and Exercise Science Laboratory (RESlab), Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland
| | - Dirk Aerenhouts
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Peter Clarys
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Ron Clijsen
- Rehabilitation and Exercise Science Laboratory (RESlab), Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
- International University of Applied Sciences THIM, Landquart, Switzerland
- Department of Health, Bern University of Applied Sciences, Berne, Switzerland
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Park L, Lum ZC, Joo JS. Allgöwer-Donati suture: A technique to preserve skin microcirculation in dermatologic surgery. J Am Acad Dermatol 2024; 90:e129-e130. [PMID: 37257776 DOI: 10.1016/j.jaad.2023.05.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 06/02/2023]
Affiliation(s)
- Lily Park
- Department of Dermatology, Larkin Community Hospital, Miami, Florida.
| | - Zachary C Lum
- College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, Florida
| | - Jayne S Joo
- Department of Dermatologic Surgery, University of California, Davis, Sacramento, California
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Neubauer-Geryk J, Wielicka M, Myśliwiec M, Zorena K, Bieniaszewski L. The Relationship between TNF-a, IL-35, VEGF and Cutaneous Microvascular Dysfunction in Young Patients with Uncomplicated Type 1 Diabetes. Biomedicines 2023; 11:2857. [PMID: 37893230 PMCID: PMC10604652 DOI: 10.3390/biomedicines11102857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/15/2023] [Accepted: 10/19/2023] [Indexed: 10/29/2023] Open
Abstract
The aim of this study was to analyze the relationship between immunological markers and the dysfunction of cutaneous microcirculation in young patients with type 1 diabetes. The study group consisted of 46 young patients with type 1 diabetes and no associated complications. Microvascular function was assessed with the use of nail fold capillaroscopy before and after implementing post-occlusive reactive hyperemia. This evaluation was then repeated after 12 months. Patients were divided into two subgroups according to their baseline median coverage (defined as the ratio of capillary surface area to surface area of the image area), which was established during the initial exam (coverageBASE). Additionally, the levels of several serum biomarkers, including VEGF, TNF-a and IL-35, were assessed at the time of the initial examination. HbA1c levels obtained at baseline and after a 12-month interval were also obtained. Mean HbA1c levels obtained during the first two years of the course of the disease were also analyzed. Patients with coverageBASE below 16.85% were found to have higher levels of VEGF and TNF-α, as well as higher levels of HbA1c during the first two years following diabetes diagnosis. Our results support the hypothesis that the development of diabetic complications is strongly influenced by metabolic memory and an imbalance of pro- and anti-inflammatory cytokines, regardless of achieving adequate glycemic control.
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Affiliation(s)
- Jolanta Neubauer-Geryk
- Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdańsk, 80-210 Gdansk, Poland; (M.W.); (L.B.)
| | - Melanie Wielicka
- Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdańsk, 80-210 Gdansk, Poland; (M.W.); (L.B.)
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Division of Neonatology, Ann Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611, USA
| | - Małgorzata Myśliwiec
- Department of Pediatrics, Diabetology and Endocrinology, Medical University of Gdansk, 80-211 Gdansk, Poland;
| | - Katarzyna Zorena
- Department of Immunobiology and Environment Microbiology, Medical University of Gdańsk, 80-211 Gdańsk, Poland;
| | - Leszek Bieniaszewski
- Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdańsk, 80-210 Gdansk, Poland; (M.W.); (L.B.)
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Takimoto B, Bito K, Hari S, Taguchi H, Haneishi H. Observation and density estimation of a large number of skin capillaries using wide-field portable video capillaroscopy and semantic segmentation. J Biomed Opt 2023; 28:106003. [PMID: 37881371 PMCID: PMC10594543 DOI: 10.1117/1.jbo.28.10.106003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 10/05/2023] [Accepted: 10/10/2023] [Indexed: 10/27/2023]
Abstract
Significance Skin capillaries are non-invasively observable; their structure and blood flow can reflect tissue and systemic conditions. Quantitative analysis of video-capillaroscopy images yields novel diagnostic methods. Because the capillary structure is heterogeneous, analyzing more capillaries can increase the evaluation reliability. Aim We developed a system that can observe and quantify numerous capillaries and verified the performance on human skin. Approach We developed a portable video-capillaroscope with a spatial resolution higher than 3.5 μ m and a wide field of view (7.4 mm × 5.5 mm ) and a method to evaluate capillary numbers and areas using U-Net. The model was trained and tested with 22 and 11 cropped images (2.4 mm × 1.9 mm ) obtained from 11 participants, respectively. They were then applied to the 7.2 mm × 5.3 mm images from four participants. Segmentation results were compared to ground-truth at the pixel level and capillary-region level. Results Over 1000 capillaries were simultaneously observed using the proposed system. Although pixel-level segmentation performance was low [intersection over union (IoU) = 24.5%], the number and area could be estimated. These values differed among four participants and seven sites, and they changed after skin barrier destruction. Conclusions The proposed system allows for observing and quantifying numerous skin capillaries simultaneously, suggesting its potential for evaluating tissue and systemic conditions.
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Affiliation(s)
- Baku Takimoto
- Kao Corporation, Analytical Science Research Laboratories, Tokyo, Japan
| | - Kotatsu Bito
- Kao Corporation, Digital Business Creation, Corporate Strategy, Tokyo, Japan
| | - Sayaka Hari
- Kao Corporation, Health and Wellness Products Research Laboratories, Tokyo, Japan
| | | | - Hideaki Haneishi
- Chiba University, Center for Frontier Medical Engineering, Chiba, Japan
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Monteiro Rodrigues L, Rocha C, Andrade S, Granja T, Gregório J. The acute adaptation of skin microcirculatory perfusion in vivo does not involve a local response but rather a centrally mediated adaptive reflex. Front Physiol 2023; 14:1177583. [PMID: 37215174 PMCID: PMC10192746 DOI: 10.3389/fphys.2023.1177583] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/17/2023] [Indexed: 05/24/2023] Open
Abstract
Introduction: Cardiovascular homeostasis involves the interaction of multiple players to ensure a permanent adaptation to each organ's needs. Our previous research suggested that changes in skin microcirculation-even if slight and distal-always evoke an immediate global rather than "local" response affecting hemodynamic homeostasis. These observations question our understanding of known reflexes used to explore vascular physiology, such as reactive hyperemia and the venoarteriolar reflex (VAR). Thus, our study was designed to further explore these responses in older healthy adults of both sexes and to potentially provide objective evidence of a centrally mediated mechanism governing each of these adaptive processes. Methods: Participants (n = 22, 52.5 ± 6.2 years old) of both sexes were previously selected. Perfusion was recorded in both feet by laser Doppler flowmetry (LDF) and photoplethysmography (PPG). Two different maneuvers with opposite impacts on perfusion were applied as challengers to single limb reactive hyperemia evoked by massage and a single leg pending to generate a VAR. Measurements were taken at baseline (Phase I), during challenge (Phase II), and recovery (Phase III). A 95% confidence level was adopted. As proof of concept, six additional young healthy women were selected to provide video imaging by using optoacoustic tomography (OAT) of suprasystolic post-occlusive reactive hyperemia (PORH) in the upper limb. Results: Modified perfusion was detected by LDF and PPG in both limbs with both hyperemia and VAR, with clear systemic hemodynamic changes in all participants. Comparison with data obtained under the same conditions in a younger cohort, previously published by our group, revealed that results were not statistically different between the groups. Discussion: The OAT documentary and analysis showed that the suprasystolic pressure in the arm changed vasomotion in the forearm, displacing blood from the superficial to the deeper plexus vessels. Deflation allowed the blood to return and to be distributed in both plexuses. These responses were present in all individuals independent of their age. They appeared to be determined by the need to re-establish hemodynamics acutely modified by the challenger, which means that they were centrally mediated. Therefore, a new mechanistic interpretation of these exploratory maneuvers is required to better characterize in vivo cardiovascular physiology in humans.
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Lazaridis A, Triantafyllou A, Mastrogiannis K, Malliora A, Doumas M, Gkaliagkousi E. ASSESSING SKIN MICROCIRCULATION IN PATIENTS AT CARDIOVASCULAR RISK BY USING LASER SPECKLE CONTRAST IMAGING. A NARRATIVE REVIEW. Clin Physiol Funct Imaging 2023. [PMID: 37020404 DOI: 10.1111/cpf.12819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/15/2023] [Accepted: 03/27/2023] [Indexed: 04/07/2023]
Abstract
Skin tissue holds a prominent role in microcirculatory research as an easily accessible vascular bed for the non-invasive evaluation of microvascular function. Skin microvascular changes have been associated to alterations in distinct target organs and vascular beds, reinforcing the hypothesis that skin microcirculation can be used as a model of generalized microvascular function. In addition, skin microvascular dysfunction has been documented in cardiovascular disease and patients of increased cardiovascular risk where it has been associated with multiple cardiovascular risk factors, rendering it a candidate surrogate marker of vascular damage. Laser Speckle Contrast Imaging (LSCI) is a non-invasive, dynamic laser technique that allows assessment of skin microvascular function (SMF) by obtaining two-dimensional maps of the skin perfusion in real time with high spatial and temporal resolution and, most importantly, with the highest reproducibility as compared to other laser methods. An ever-increasing number of studies using LSCI is confirming evidence of impaired SMF in several cardiovascular risk groups, therefore expanding its application in microvascular research and showing its potential clinical utility. This review attempts to present the growing importance of SMF in cardiovascular research and the emergence of LSCI technique as a robust imaging modality with a promising role to explore skin microvascular physiology. After a short description of the relevant technique and its main principle of function, we have also opted to present the most up to date studies using LSCI for the investigation of SMF in patients with cardiovascular disease as well as various groups of increased cardiovascular risk. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- A Lazaridis
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - A Triantafyllou
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - K Mastrogiannis
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - A Malliora
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - M Doumas
- 2nd Propedeutic Department of Internal Medicine, Hippokrateio Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - E Gkaliagkousi
- 3rd Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Wikslund LK, Kaljusto M, Amundsen VS, Kvernebo K. Microvascular remodeling following skin injury. Microcirculation 2022; 29:e12755. [PMID: 35231135 PMCID: PMC9788271 DOI: 10.1111/micc.12755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 02/01/2022] [Accepted: 02/15/2022] [Indexed: 12/30/2022]
Abstract
OBJECTIVE The aim of this study was to describe possible remodeling (i.e., dilatation and elongation) of papillary capillaries induced by increased oxygen demand for the repair process following a skin wound. METHODS Computer-assisted video microscopy was used to examine 10 healthy volunteers before (baseline) and after (≈1 h and ≈24 h) an incision (5 mm long and 1 mm deep) on the forearm, 0-1 mm and 30 mm (control site) from the incision. We defined categories from 0 (low) to 3 (high) to grade dilatation and elongation of the nutritive papillary capillaries, as well as the visibility of the superficial vascular plexus. Approximately 10 000 capillaries from 200 films were scored. RESULTS The nutritive papillary capillaries were dilated and elongated (p < 0.01) after ≈24 h; that is, elongation (score 1.9 ± 0.9) vs baseline (score 0.9 ± 0.6), p < 0.01 and dilatation (score 2.2 ± 0.7) vs baseline (score 0.3 ± 0.3), p < 0.01. Superficial plexus visibility increased (p < 0.01) after ≈1 h (score 2.0 ± 0.7) and ≈24 h (score 2.7 ± 0.3) vs baseline (score 0.8 ± 0.4). CONCLUSION The superficial vascular skin plexus showed enhanced visibility already ≈1 h after the skin trauma. Morphological remodeling in the nutritive papillary capillaries-dilatation and elongation after ≈24 h-facilitate increased O2 supply.
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Affiliation(s)
- Liv Kristin Wikslund
- Ostfold Hospital TrustGralumNorway,Circulation laboratoryDepartment of Cardio‐thoracic SurgeryOslo University HospitalUllevaalNorway,Medical FacultyUniversity of OsloOsloNorway
| | | | - Vivian Shubira Amundsen
- Circulation laboratoryDepartment of Cardio‐thoracic SurgeryOslo University HospitalUllevaalNorway
| | - Knut Kvernebo
- Circulation laboratoryDepartment of Cardio‐thoracic SurgeryOslo University HospitalUllevaalNorway,Medical FacultyUniversity of OsloOsloNorway,Department of Cardiothoracic SurgeryOslo University HospitalOsloNorway
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Schäfer RC, Sohn A, Kersten A, Amr A, Held M, Wenger A. Quantification of Dermal Microcirculatory Changes after Topical Administration of Capsaicin: A Randomized Placebo-Controlled Study in 46 Subjects. J INVEST SURG 2022; 35:1673-1678. [PMID: 35836365 DOI: 10.1080/08941939.2022.2091694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Dermal blood flow is crucial for wound healing and survival of flaps in dermatologic surgery. To improve flap viability in cases of compromised perfusion topical agents can easily be applied. The aim of this placebo-controlled study was to characterize changes of DBF in healthy subjects by quantitatively assessing perfusion dynamics after application of capsaicin to establish a reference for measurements at injured sites. METHODS In 46 healthy subjects perfusion dynamics after local application with capsaicin and placebo was noninvasively assessed, determining cutaneous oxygen saturation, relative hemoglobin count and blood flow using an Oxygen-to-See device. RESULTS A significant raise in superficial (162% p = 0.000) and deep (144%, p = 0.000) skin oxygenation after 30 min was provoked. A highly significant raise in measurements of flow and velocity was present in superficial (523%, p = 0.000) and deep (242%, p = 0.000) sites. CONCLUSION With the introduced model applied to observe changes in parameters of dermal blood flow in healthy subjects the authors can reliably monitor effects of topically administered capsaicin. This baseline can be used as reference for further studies in the settings of endangered flap survival or critically perfused wounds as has been proven in animal studies.
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Affiliation(s)
- Ruth Christine Schäfer
- Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tübingen, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Anna Sohn
- Department of Dermatology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Anabel Kersten
- Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tübingen, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Amro Amr
- Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tübingen, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Manuel Held
- Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tübingen, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Andrea Wenger
- Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tübingen, Eberhard Karls University Tuebingen, Tuebingen, Germany
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Ewerlöf M, Strömberg T, Larsson M, Salerud EG. Multispectral snapshot imaging of skin microcirculatory hemoglobin oxygen saturation using artificial neural networks trained on in vivo data. J Biomed Opt 2022; 27:036004. [PMID: 35340134 PMCID: PMC8957373 DOI: 10.1117/1.jbo.27.3.036004] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 03/03/2022] [Indexed: 06/14/2023]
Abstract
SIGNIFICANCE Developing algorithms for estimating blood oxygenation from snapshot multispectral imaging (MSI) data is challenging due to the complexity of sensor characteristics and photon transport modeling in tissue. We circumvent this using a method where artificial neural networks (ANNs) are trained on in vivo MSI data with target values from a point-measuring reference method. AIM To develop and evaluate a methodology where a snapshot filter mosaic camera is utilized for imaging skin hemoglobin oxygen saturation (SO2), using ANNs. APPROACH MSI data were acquired during occlusion provocations. ANNs were trained to estimate SO2 with MSI data as input, targeting data from a validated probe-based reference system. Performance of ANNs with different properties and training data sets was compared. RESULTS The method enables spatially resolved estimation of skin tissue SO2. Results are comparable to those acquired using a Monte-Carlo-based approach when relevant training data are used. CONCLUSIONS Training an ANN on in vivo MSI data covering a wide range of target values acquired during an occlusion protocol enable real-time estimation of SO2 maps. Data from the probe-based reference system can be used as target despite differences in sampling depth and measurement position.
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Affiliation(s)
- Maria Ewerlöf
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Tomas Strömberg
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Marcus Larsson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - E. Göran Salerud
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
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Serov D, Tankanag A, Astashev M. Low-frequency oscillations of murine skin microcirculations and periodic changes of [Ca 2+ ] i and [NO] i levels in murine endotheliocytes: An effect of provocative tests. Cell Biol Int 2021; 46:427-442. [PMID: 34882893 DOI: 10.1002/cbin.11743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 11/07/2021] [Accepted: 12/04/2021] [Indexed: 01/14/2023]
Abstract
The five frequency intervals of skin blood oscillation were described: cardiac, respiratory, myogenic, neurogenic, and endothelial. The endothelial interval is derived into NO-independent and NO-dependent. The exact molecular, cell, or systemic mechanisms of endothelial oscillations generation are unclear. We proposed that oscillations of Ca2+ and NO in endotheliocytes may be possible sources of skin blood perfusion (SBP) oscillations in endothelial interval. To examine our hypothesis we compared the oscillations of cytoplasmic Ca2+ and NO ([Ca2+ ]i and [NO]i ) concentration in cultured murine microvascular endotheliocytes and SBP oscillations in mice. Local heating test and model hypoxia were used as tools to evaluate an interconnection of studied parameters. [Ca2+ ]i and [NO]i were measured simultaneously by Fura-2 AM and DAF-FM. The SBP was measured by laser Doppler flowmetry. The [Ca2+ ]i and [NO]i oscillations at 0.005-0.01 Hz were observed in endotheliocytes, that coincides the ranges of NO-independent endothelial interval. Heating decreased amplitude of [Ca2+ ]i and [NO]i oscillations in cells in NO-independent endothelial interval, while amplitudes of SBP oscillations increased in NO-independent and NO-dependent intervals. Hypoxia reduced the [NO]i oscillations amplitude. Heating test during hypoxia increased NO-independent endothelial SBP oscillations and decreased myogenic ones, did not effect on [NO]i oscillations, and shifted [Ca2+ ]i oscillations peak from 0.005-0.01 Hz to 0.01-0.018 Hz. We observed the [Ca2+ ]i and [NO]i oscillations synchronization within a cell and between cells for the first time. Heating abolished these synchronizations. Therefore low-frequency [Ca2+ ]i and [NO]i oscillations in endotheliocytes may be considered as modulators of low-frequency endothelial SBP oscillations.
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Affiliation(s)
- Dmitriy Serov
- Institute of Cell Biophisics, Russian Academy of Sciences, Laboratory of Cellular Neurobiology, Pushchino, Moscow region, Russia.,Prokhorov General Physics Institute of the Russian Academy of Sciences, Biophotonics Center, Moscow, Russia
| | - Arina Tankanag
- Institute of Cell Biophisics, Russian Academy of Sciences, Laboratory of Cellular Neurobiology, Pushchino, Moscow region, Russia
| | - Maksim Astashev
- Institute of Cell Biophisics, Russian Academy of Sciences, Laboratory of Cellular Neurobiology, Pushchino, Moscow region, Russia.,Prokhorov General Physics Institute of the Russian Academy of Sciences, Biophotonics Center, Moscow, Russia
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Wikslund LK, Amundsen VS, Kvernebo AK, Standal ØKV, Kvernebo K. Skin trauma rapidly induces thermoregulatory plexus hyperemia, while an increased nutritive papillary capillary function can be detected after 24 h. Microcirculation 2021; 29:e12735. [PMID: 34748662 DOI: 10.1111/micc.12735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 10/30/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Clinical assessments and laser Doppler perfusion measurements (LDPM) of skin microcirculation have limited value, as they fail to capture events regulated by local metabolic needs at a papillary capillary level. This study aimed to examine the ability of computer-assisted video microscopy (CAVM) and diffuse reflectance spectroscopy (DRS) to assess skin nutritive perfusion-compared to LDPM. METHODS Healthy volunteers (n = 10) were examined after (≈1 and ≈24 h) an incision (5 × 1 mm) on the forearm, at 0.1 mm (only with CAVM), 2-3 mm, and 30 mm from the trauma. RESULTS No changes were detected by CAVM after ≈1 h. After ≈24 h, 0-1 mm from the trauma, both CAVM parameters were increased: functional capillary density (capillary crossings/mm, 11.8 ± 1.4 vs. 7.3 ± 1.2, p < .01) and capillary flow velocities (CFV, %capillaries with brisk flow, 10 ± 6.8 vs. 1 ± 1, p < .01). At a distance of 2-3 mm, only CFV was increased (6.2 ± 6.1 vs. 1 ± 1, p < .05). DRS and LDPM measurements increased 2-3 mm from the trauma line in relation to baseline after both ≈1 and ≈24 h, that is, with DRS (%microvascular oxygen saturation): 45.8 ± 7.4% (baseline), 70.0 ± 12.5% (≈1 h), and 73.1 ± 10.4% (≈24 h), p < .01 and with LDPM (a.u.): 7.2 ± 2.5 (baseline), 28.3 ± 18.7 (≈1 h), and 45.9 ± 16.3 (≈24 h), p < .01. CONCLUSIONS ≈24 h after skin trauma, an increased function of the nutritive papillary capillaries can be detected by CAVM.
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Affiliation(s)
- Liv Kristin Wikslund
- Ostfold Hospital Trust, Sarpsborg, Norway
- The Circulation Laboratory, Department of Cardio-thoracic Surgery, Oslo University Hospital, Ullevaal, Oslo, Norway
- Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway
| | - Vivian Shubira Amundsen
- The Circulation Laboratory, Department of Cardio-thoracic Surgery, Oslo University Hospital, Ullevaal, Oslo, Norway
- Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway
| | - Anne Kari Kvernebo
- The Circulation Laboratory, Department of Cardio-thoracic Surgery, Oslo University Hospital, Ullevaal, Oslo, Norway
- Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway
- Department of Ophthalmology, Oslo University Hospital HF, Oslo, Norway
| | | | - Knut Kvernebo
- The Circulation Laboratory, Department of Cardio-thoracic Surgery, Oslo University Hospital, Ullevaal, Oslo, Norway
- Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway
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13
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Thorn CE, Adio AO, Fox RH, Gardner AM, Winlove CP, Shore AC. Intermittent compression induces transitory hypoxic stimuli, upstream vasodilation and enhanced perfusion of skin capillaries, independent of age and diabetes. J Appl Physiol (1985) 2021; 130:1072-1084. [PMID: 33571053 DOI: 10.1152/japplphysiol.00657.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The benefit of enhanced shear stress to the vascular endothelium has been well-documented in conduit arteries but is less understood in skin microcirculation. The aim of this study was to provide physiological evidence of the vascular changes in skin microcirculation induced by intermittent pneumatic compression (IPC) of 1 s cuff inflation (130 mmHg) every 20 s to the palm of the hand for 30 min. The oxygenation and hemodynamics of dorsal mid-phalangeal finger skin microcirculation were assessed by laser Doppler fluximetry and reflectance spectroscopy before, during, and after IPC in 15 young (18-39 years old) and 39 older (40-80 years old) controls and 32 older subjects with type 2 diabetes mellitus. Each individual cuff inflation induced: 1) brief surge in flux immediately after cuff deflation followed by 2) transitory reduction in blood oxygen for ∼4 s, and 3) a second increase in perfusion and oxygenation of the microcirculation peaking ∼11 s after cuff deflation in all subject groups. With no significant change in blood volume observed by reflectance spectroscopy, despite the increased shear stress at the observed site, this second peak in flux and blood oxygen suggests a delayed vasoactive response upstream inducing increased arterial influx in the microcirculation that was higher in older controls and subjects with diabetes compared to young controls (P < 0.001, P < 0.001, respectively) and achieving maximum capillary recruitment in all subject groups. Transitory hypoxic stimuli with conducted vasodilation may be a mechanism through which IPC enhances capillary perfusion in skin microcirculation independent of age and type 2 diabetes mellitus.NEW & NOTEWORTHY This study demonstrates that hand intermittent pneumatic compression evokes transitory hypoxic stimuli in distal finger skin microcirculation inducing vasodilation of arterial inflow vessels, enhanced perfusion, and maximum capillary recruitment in young and older subjects and older subjects with type 2 diabetes mellitus. Enhanced shear stress in the microcirculation did not appear to induce local skin vasodilation.
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Affiliation(s)
- Clare E Thorn
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Aminat O Adio
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Roger H Fox
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - A Michael Gardner
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - C Peter Winlove
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Angela C Shore
- Diabetes and Vascular Medicine, Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, College of Medicine and Health and NIHR Exeter Clinical Research Facility, and School of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
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14
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Ewerlöf M, Salerud EG, Strömberg T, Larsson M. Estimation of skin microcirculatory hemoglobin oxygen saturation and red blood cell tissue fraction using a multispectral snapshot imaging system: a validation study. J Biomed Opt 2021; 26:JBO-200291RR. [PMID: 33583154 PMCID: PMC7881095 DOI: 10.1117/1.jbo.26.2.026002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 01/13/2021] [Indexed: 05/08/2023]
Abstract
SIGNIFICANCE Hemoglobin oxygen saturation and red blood cell (RBC) tissue fraction are important parameters when assessing microvascular status. Functional information can be attained using temporally resolved measurements performed during stimulus-response protocols. Pointwise assessments can currently be conducted with probe-based systems. However, snapshot multispectral imaging (MSI) can be used for spatial-temporal measurements. AIM To validate if hemoglobin oxygen saturation and RBC tissue fraction can be quantified using a snapshot MSI system and an inverse Monte Carlo algorithm. APPROACH Skin tissue measurements from the MSI system were compared to those from a validated probe-based system during arterial and venous occlusion provocation on 24 subjects in the wavelength interval 450 to 650 nm, to evaluate a wide range of hemoglobin oxygen saturation and RBC tissue fraction levels. RESULTS Arterial occlusion results show a mean linear regression R2 = 0.958 for hemoglobin oxygen saturation. Comparing relative RBC tissue fraction during venous occlusion results in R2 = 0.925. The MSI system shows larger dynamic changes than the reference system, which might be explained by a deeper sampling including more capacitance vessels. CONCLUSIONS The snapshot MSI system estimates hemoglobin oxygen saturation and RBC tissue fraction in skin microcirculation showing a high correlation (R2 > 0.9 in most subjects) with those measured by the reference method.
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Affiliation(s)
- Maria Ewerlöf
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - E. Göran Salerud
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Tomas Strömberg
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Marcus Larsson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
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15
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Gryglewska B, Głuszewska A, Zarzycki B, Dzieża-Grudnik A, Fedyk-Łukasik M, Major P, Budzyński A, Gąsowski J, Grodzicki T. Post-occlusive reactive hyperemic response of skin microcirculation among extremely obese patients in the short and long term after bariatric surgery. Microcirculation 2019; 27:e12600. [PMID: 31782233 DOI: 10.1111/micc.12600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/25/2019] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To assess changes of post-occlusive reactive hyperemic response in skin microcirculation among extremely obese patients 10 days and 6 months after bariatric surgery for patients with and without hypertension. METHODS Skin blood flow was measured using PeriFlux laser Doppler fluxmetry. Data were analyzed in the entire group and two subgroups: with and without hypertension. RESULTS Data from 88 patients (mean age 42.1 ± 11.2 years, 40.5% men) were analyzed. Six months after bariatric surgery, the time to reach peak flows had been shortened (2.4 ± 1.7 vs 2.1 ± 1.0 seconds, P < .05) and the area of hyperemia had increased (1027 ± 791 vs 1386 ± 699 AU*s, P < .05). The total power of post-occlusive reactive hyperemic after occlusion had been augmented mainly with power intensification of endothelial and myogenic origin. Post-occlusive reactive hyperemic parameters had changed mainly in the subgroup with hypertension. Variations of anthropometric parameters, metabolic characteristic, and adipokines mainly influenced on studied hyperemic flow parameters variations after the intervention in multiple regression analysis. CONCLUSION Cutaneous post-occlusive reactive hyperemic reactivity in time and frequency domains improved 6 months after bariatric surgery, and improvements in microvascular function were observed mainly in patients with hypertension. Variations of anthropometric parameters, metabolic characteristics, and adipokines had influence on hyperemic flow reactivity.
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Affiliation(s)
- Barbara Gryglewska
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Anna Głuszewska
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Bartosz Zarzycki
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Anna Dzieża-Grudnik
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Małgorzata Fedyk-Łukasik
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Piotr Major
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland.,2nd Department of General Surgery, Medical College, Jagiellonian University, Kraków, Poland
| | - Andrzej Budzyński
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland.,2nd Department of General Surgery, Medical College, Jagiellonian University, Kraków, Poland
| | - Jerzy Gąsowski
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
| | - Tomasz Grodzicki
- Department of Internal Medicine and Gerontology, Medical College, Jagiellonian University, Kraków, Poland
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16
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Argarini R, McLaughlin RA, Naylor LH, Carter HH, Green DJ. Assessment of the human cutaneous microvasculature using optical coherence tomography: Proving Harvey's proof. Microcirculation 2019; 27:e12594. [PMID: 31585482 DOI: 10.1111/micc.12594] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/05/2019] [Accepted: 09/18/2019] [Indexed: 12/15/2022]
Abstract
William Harvey proved the circulation of blood 400 years ago using a combination of ligature application and astute observation that presaged the existence of capillaries. Here we report findings, based on our development of a novel application of optical coherence tomography (OCT), that directly confirm the impact of cuff inflation on microvessels as small as ~30µm. By emulating Harvey's proofs, using cuff inflation at low pressure in the presence and absence of skin heating, we have imaged and quantified significant effects on microvascular diameter and density in humans in vivo. The application of cuff pressure significantly increased microvascular diameter (40.5 ± 4.6 vs 47.1 ± 3.9 µm, P = .01) and density (8.33 ± 4.3 vs 15.1 ± 4.9%, P < .01). These impacts were reversed by cuff deflation. Our study also showed the profound impacts of skin heating on microvessel diameter (46.7 ± 5.8 vs 70.6 ± 7.8 µm, P < .01) and density (14.2 ± 6.5 vs 43.2 ± 9%, P < .01) in vivo, which were further exacerbated by cuff inflation. Our approach to the direct visualization of the human skin microvasculature is non-invasive, safe, and easily applied. Future experiments might be directed at questions of microvascular physiology and pathophysiology, such as how different mammals thermoregulate and what impacts cardiovascular disease and diabetes have on microvascular structure and function.
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Affiliation(s)
- Raden Argarini
- Physiology Department, Faculty of Medicine, Airlangga University, Surabaya, Indonesia.,Cardiovascular Research Group, School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth, WA, Australia
| | - Robert A McLaughlin
- Faculty of Health and Medical Sciences, Australian Research Council Centre of Excellence for Nanoscale Biophotonics, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia.,Institute for Photonics and Advanced Sensing, University of Adelaide, Adelaide, SA, Australia
| | - Louise H Naylor
- Cardiovascular Research Group, School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth, WA, Australia
| | - Howard H Carter
- Cardiovascular Research Group, School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth, WA, Australia
| | - Daniel J Green
- Cardiovascular Research Group, School of Human Sciences (Exercise and Sport Science), The University of Western Australia, Perth, WA, Australia
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Neubauer-Geryk J, Hoffmann M, Wielicka M, Piec K, Kozera G, Bieniaszewski L. Current methods for the assessment of skin microcirculation: Part 2. Postepy Dermatol Alergol 2019; 36:377-81. [PMID: 31616209 DOI: 10.5114/ada.2019.83657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/22/2018] [Indexed: 11/17/2022] Open
Abstract
Microcirculation accounts for about 99% of blood vessels in adults and mediates between the arterial and venous parts of the cardiovascular system, both structurally and functionally. Skin microcirculation consists of two vascular plexuses: superficial and deep. Microcirculation includes vessels with a diameter of less than 150 μm, i.e. arteries, small veins, lymphatic vessels and arteriovenous anastomoses, which build the microcirculation unit. Skin microcirculation may be affected both in systemic pathologies and specific skin disorders. Several non-invasive techniques are available to assess the skin microcirculation. Methods used in clinical practice were presented previously in Advances in Dermatology and Allergology. The current article describes methods that may be used in clinical research.
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18
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Neubauer-Geryk J, Hoffmann M, Wielicka M, Piec K, Kozera G, Brzeziński M, Bieniaszewski L. Current methods for the assessment of skin microcirculation: Part 1. Postepy Dermatol Alergol 2019; 36:247-254. [PMID: 31333339 PMCID: PMC6640017 DOI: 10.5114/ada.2019.83656] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/22/2018] [Indexed: 11/17/2022] Open
Abstract
Microcirculation accounts for about 99% of blood vessels in adults and mediates between the arterial and venous parts of the cardiovascular system, both structurally and functionally. Skin microcirculation consists of two vascular plexuses: superficial and deep. Microcirculation includes vessels with a diameter of less than 150 μm, i.e. arteries, small veins, lymphatic vessels and arteriovenous anastomoses, which build the microcirculation unit. Skin microcirculation may be affected both in systemic pathologies and specific skin disorders. Several non-invasive techniques are available to assess the skin microcirculation. The clinical value is recognised for capillaroscopy and videocapillaroscopy, laser Doppler flowmetry thermography and transcutaneous oxygen measurement. The list of methods that may be used in clinical research also includes: photoplethysmography, orthogonal spectral polarization, near infrared spectroscopy and tissue reflectance spectrophotometry and optical coherence tomography.
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Affiliation(s)
- Jolanta Neubauer-Geryk
- Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdansk, Gdansk, Poland
| | | | - Melanie Wielicka
- Clinical Physiology Unit, Medical Simulation Centre/Students’ Scientific Circle, Medical University of Gdansk, Gdansk, Poland
| | - Katarzyna Piec
- Department of Neurology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Poland
| | - Grzegorz Kozera
- Department of Neurology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Poland
| | - Maciej Brzeziński
- Department of Cardiac and Vascular Surgery, Medical University of Gdansk, Gdansk, Poland
| | - Leszek Bieniaszewski
- Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdansk, Gdansk, Poland
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19
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Santesson P, Lins PE, Kalani M, Adamson U, Lelic I, von Wendt G, Fagrell B, Jörneskog G. Skin microvascular function in patients with type 1 diabetes: An observational study from the onset of diabetes. Diab Vasc Dis Res 2017; 14:191-199. [PMID: 28467200 DOI: 10.1177/1479164117694463] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The development of disturbances in skin microcirculation in type 1 diabetes is not well characterised. We assessed skin microcirculation longitudinally from the onset of diabetes up to 29 years of duration to investigate when such disturbances start. MATERIAL AND METHODS Seventeen adult patients with type 1 diabetes participated. Skin microvascular function in digit IV of the left hand was investigated by laser Doppler fluxmetry (LDF, arbitrary units [AU]). LDF was carried out at rest and following one-min arterial occlusion. Time to peak LDF (s) and percentage increase of LDF (post-occlusive reactive hyperaemia, PRH%) were determined. Retinopathy was assessed from fundus photographs or ophthalmoscopic recordings. RESULTS Skin microvascular function remained normal during the first five years. Compared with baseline and a non-diabetic reference group, time to peak LDF was prolonged after 7-9 years of diabetes ( p < 0.01). PRH% was lower than in the reference group after 7-9 years ( p < 0.01), and lower than baseline after 24-29 years of diabetes ( p < 0.05). All but one patient developed retinopathy and the first signs were found after 10 years of diabetes. CONCLUSIONS Functional disturbances in total skin microcirculation were observed after seven years in patients with type 1 diabetes and preceded diabetic complications such as retinopathy.
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Affiliation(s)
- Pia Santesson
- 1 Microcirculatory Laboratory, Division of Medicine, Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
| | - Per-Eric Lins
- 1 Microcirculatory Laboratory, Division of Medicine, Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
| | - Majid Kalani
- 2 Division of Cardiovascular Medicine, Department of Clinical sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
| | - Ulf Adamson
- 1 Microcirculatory Laboratory, Division of Medicine, Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
| | - Isak Lelic
- 1 Microcirculatory Laboratory, Division of Medicine, Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
| | - Gunvor von Wendt
- 3 Department of Medical Retina, Karolinska Institutet, St. Erik Eye Hospital, Stockholm, Sweden
| | - Bengt Fagrell
- 4 Department of Medicine, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Gun Jörneskog
- 1 Microcirculatory Laboratory, Division of Medicine, Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
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20
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Wang H, Baran U, Wang RK. In vivo blood flow imaging of inflammatory human skin induced by tape stripping using optical microangiography. J Biophotonics 2015; 8:265-72. [PMID: 24659511 PMCID: PMC4308563 DOI: 10.1002/jbio.201400012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 02/25/2014] [Accepted: 02/27/2014] [Indexed: 05/03/2023]
Abstract
Vasculature response is a hallmark for most inflammatory skin disorders. Tape stripping on human skin causes a minor inflammation which leads to changes in microvasculature. In this study, optical microangiography (OMAG), noninvasive volumetric microvasculature in vivo imaging method, has been used to track the vascular responses after tape stripping. Vessel density has been quantified and used to correlate with the degree of skin irritation. The proved capability of OMAG technique in visualizing the microvasculature network under inflamed skin condition can play an important role in clinical trials of treatment and diagnosis of inflammatory skin disorders.
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Affiliation(s)
- Hequn Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Utku Baran
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
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21
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Chang K, Yoon S, Sheth N, Seidel M, Antalek M, Ahad J, Darlington T, Ikeda A, Kato GJ, Ackerman H, Gorbach AM. Rapid vs. delayed infrared responses after ischemia reveal recruitment of different vascular beds. Quant Infrared Thermogr J 2015; 12:173-183. [PMID: 26435756 PMCID: PMC4589278 DOI: 10.1080/17686733.2015.1046677] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Continuous infrared imaging revealed transient changes in forearm temperature during arterial occlusion, reperfusion, and recovery in a healthy subject group. Processing the imaging data with the k-means algorithm further revealed reactive vascular sites in the skin with rapid or delayed temperature amplification. The observed temporal and spatial diversity of blood-flow-derived forearm temperature allow consideration of thermal-imaging guided placement of skin sensors to achieve enhanced sensitivity in monitoring of skin hemodynamics.
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Affiliation(s)
- Ken Chang
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Stephen Yoon
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Niral Sheth
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Miles Seidel
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Matthew Antalek
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - James Ahad
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Thomas Darlington
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Allison Ikeda
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Gregory J. Kato
- The Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
- Division of Hematology/Oncology, Vascular Medicine Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Hans Ackerman
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Alexander M. Gorbach
- Infrared Imaging and Thermometry Unit, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
- Corresponding author.
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22
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Baran U, Shi L, Wang RK. Capillary blood flow imaging within human finger cuticle using optical microangiography. J Biophotonics 2015; 8:46-51. [PMID: 25590582 PMCID: PMC4304076 DOI: 10.1002/jbio.201300154] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 05/19/2023]
Abstract
We report non-invasive 3D imaging of capillary blood flow within human finger cuticle by the use of Doppler optical microangiography (DOMAG) and ultra-high sensitive optical microangiography (UHS-OMAG) techniques. Wide velocity range DOMAG method is applied to provide red blood cell (RBC) axial velocity mapping in capillary loops with ranges of ±0.9 mm/s and ±0.3 mm/s. Additionally, UHS-OMAG technique is engineered to acquire high resolution image of capillary morphology. The presented results are promising to facilitate clinical trials of treatment and diagnosis of various diseases such as diabetes, Raynaud's phenomenon, and connective tissue diseases by quantifying cutaneous blood flow changes within human finger cuticle.
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Affiliation(s)
- Utku Baran
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Lei Shi
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
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23
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Loos N, Thuróczy G, Ghosn R, Brenet-Dufour V, Liabeuf S, Selmaoui B, Libert JP, Bach V, Diouf M, de Seze R. Is the effect of mobile phone radiofrequency waves on human skin perfusion non-thermal? Microcirculation 2014; 20:629-36. [PMID: 23590124 DOI: 10.1111/micc.12062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 04/12/2013] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To establish whether SkBF can be modified by exposure to the radiofrequency waves emitted by a mobile phone when the latter is held against the jaw and ear. METHODS Variations in SkBF and Tsk in adult volunteers were simultaneously recorded with a thermostatic laser Doppler system during a 20-minute "radiofrequency" exposure session and a 20-minute "sham" session. The skin microvessels' vasodilatory reserve was assessed with a heat challenge at the end of the protocol. RESULTS During the radiofrequency exposure session, SkBF increased (vs. baseline) more than during the sham exposure session. The sessions did not differ significant in terms of the Tsk time-course response. The skin microvessels' vasodilatory ability was found to be greater during radiofrequency exposure than during sham exposure. CONCLUSIONS Our results reveal the existence of a specific vasodilatory effect of mobile phone radiofrequency emission on skin perfusion.
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Affiliation(s)
- Nathalie Loos
- PériTox Laboratory (EA 4285-UMI01), Faculty of Medicine, Jules Verne University of Picardy, Amiens, France
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Lamprecht M, Obermayer G, Steinbauer K, Cvirn G, Hofmann L, Ledinski G, Greilberger JF, Hallstroem S. Supplementation with a juice powder concentrate and exercise decrease oxidation and inflammation, and improve the microcirculation in obese women: randomised controlled trial data. Br J Nutr 2013; 110:1685-95. [PMID: 23591157 PMCID: PMC3821373 DOI: 10.1017/s0007114513001001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/05/2013] [Accepted: 03/05/2013] [Indexed: 01/03/2023]
Abstract
Obesity and sedentary lifestyle are associated with increased oxidative stress, inflammation and vessel dysfunction. Previous research has shown that an encapsulated fruit/berry/vegetable juice powder (FBV) supplement or controlled exercise training improve the markers of redox biology, low-grade inflammation and circulation. The aim of the present study was to assess the effects of 8 weeks of supplementation with FBV or placebo, and a single bout of controlled walking on the markers of oxidation, inflammation and skin capillary microcirculation in forty-two obese pre-menopausal women (41 (SD 5) years, non-smokers and BMI 34·5 (SD 3·8) kg/m(2)) using a randomised, double-blind, placebo-controlled design. All assessments were made before and after 8 weeks of capsule supplementation, and pre- and post-30 min of controlled treadmill walking at 70 % of VO2max. Venous blood was collected for the determination of carbonyl proteins (CP), oxidised LDL (ox-LDL), total oxidation status (TOS) of lipids, malondialdehyde, TNF-α and IL-6. Capillary blood flow, O2 saturation of Hb (SO2Hb) and the relative concentration of Hb (rHb) were assessed at a 2 mm skin depth. Following 8 weeks of supplementation, compared with placebo, the FBV group had a significant (P< 0·05) reduction in CP, ox-LDL, TOS and TNF-α, and a significant increase in blood flow, SO2Hb and rHb. Independent of supplementation, moderate exercise significantly increased blood flow and rHb, with a trend towards increased SO2Hb. Compared with placebo, 8 weeks of supplementation with FBV decreased the markers of systemic oxidation and inflammation. Both FBV supplementation and a single walking bout improved the markers of the microcirculation in these obese women.
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Affiliation(s)
- Manfred Lamprecht
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
- Institute of Nutrient Research and Sport Nutrition, Petersbergenstrasse 95b, 8042Graz, Austria
| | - Georg Obermayer
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
- Institute of Nutrient Research and Sport Nutrition, Petersbergenstrasse 95b, 8042Graz, Austria
| | - Kurt Steinbauer
- SportchirurgiePlus, Centre for Individual Sport Medicine and Surgery, Berthold Linderweg 15, 8047Graz, Austria
| | - Gerhard Cvirn
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
| | - Lidija Hofmann
- FH JOANNEUM, University of Applied Sciences, Eggenberger Allee 11, 8020Graz, Austria
| | - Gerhard Ledinski
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
| | - Joachim F. Greilberger
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
- Institute of Laboratory Sciences, Dr Greilberger GmbH, Hauptstrasse 140, 8301Laßnitzhöhe, Austria
| | - Seth Hallstroem
- Institute of Physiological Chemistry, Centre for Physiological Medicine, Medical University of Graz, Harrachgasse 21/II, 8010 Graz, Austria
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Fredly S, Fugelseth D, Wester T, Häggblad E, Kvernebo K. Skin microcirculation in healthy term newborn infants--assessment of morphology, perfusion and oxygenation. Clin Hemorheol Microcirc 2013; 59:309-22. [PMID: 24002120 DOI: 10.3233/ch-131764] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
UNLABELLED Despite microcirculation's fundamental role, assessments of its function are limited. We explored the applicability of Computer Assisted Video Microscope (CAVM), Laser Doppler Perfusion Measurements (LDPM) and Diffuse Reflectance Spectroscopy (DRS) to study skin microvascular morphology, perfusion and oxygen saturation in twenty-five healthy newborns day 1-3 of life. RESULTS Day 1-3 (mean (SD)): Microvascular density (CAVM; number of microvessels crossing a grid of lines/mm line, c/mm): Chest: 11.3 (1.5), 11.0 (1.7), 10.7 (1.6). Hand: 13.2 (2.0), 13.2 (1.9), 12.4 (1.6). Capillary density was significantly higher in the hand than in the chest each day (p < 0.001). Perfusion (LDPM; arbitrary units): Chest: 109.1 (26.0), 101.4 (24.6), 100.8 (25.3). Hand: 58.9 (17.5), 54.3 (15.8), 46.9 (14.8). Perfusion was significantly higher in the chest than in the hand each day (p < 0.01). Microvascular oxygen saturation (DRS; %): Chest: 88.1 (5.2), 87.8 (10.0), 86.7 (9.0). Hand: 79.9 (15.2), 82.7 (11.8), 82.2 (12.1) (p < 0.05). Capillary flow velocities (CAVM) were similar in the chest and hand: 60-70% capillaries had "continuous high flow" and 30-40% "continuous low flow".Multimodal skin microvascular assessments with CAVM, LDPM and DRS are feasible with reproducible data in newborns. The hand has lower perfusion, higher capillary density and higher oxygen extraction than the chest.
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Affiliation(s)
- Siv Fredly
- Department of Neonatal Intensive Care, Oslo University Hospital, Ullevål, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Drude Fugelseth
- Department of Neonatal Intensive Care, Oslo University Hospital, Ullevål, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Torjus Wester
- Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Cardiothoracic Surgery, Oslo University Hospital, Ullevål, Oslo, Norway
| | - Erik Häggblad
- Department of Neonatal Intensive Care, Oslo University Hospital, Ullevål, Oslo, Norway.,Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Knut Kvernebo
- Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Cardiothoracic Surgery, Oslo University Hospital, Ullevål, Oslo, Norway
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Abstract
Background Stellate ganglion block (SGB) is a widely used procedure for treatment of pain in the head and upper body, but the clinical signs used to verify the effectiveness of SGB can be ambiguous or variable in some patients. We observed the chronological changes in perfusion index (PI) from pulse oximetry to determine if these changes correlated with the clinical signs associated with an effective SGB. We hypothesized that PI could provide an easy method to assess the effectiveness of SGB. Method We compared the chronologies in PI on the treated and untreated sides of 21 patients in whom treatment by SGB was found to be effective. The SGB was performed by administering 6 mL of 1% mepivacaine. The effectiveness of the SGB was confirmed on the basis of clinical signs. Additionally, in two patients we tested whether increased PI on the treatment side correlated with increased microcirculation as measured by laser-Doppler blood flowmetry. Results On the side treated by SGB, PI increased 61.4% in the earlobe and 60.5% from baseline values in the upper limbs, at 5 minutes after initiation of the procedure. Differences in PI before and after treatment were significant at both sites. No time-course increases in PI were found on the untreated side at either site. Following SGB, increases in PI correlated with increases in blood flow as measured by laser-Doppler flowmetry. Conclusion PI increased in the earlobe and upper limbs on the treated side of 21 patients who received an effective SGB but not on the untreated side. The positive correlations between changes in PI and both presence of clinical signs and changes in blood flow in the skin microcirculation indicate a sympatholytic effect, suggesting that the PI could be useful in determination of the efficacy of SGB.
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Affiliation(s)
- Hajime Yamazaki
- Department of Anesthesiology, Surgical Science, Tokai University School of Medicine, Kanagawa, Japan
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Liu WM, Maivelett J, Kato GJ, Taylor JG, Yang WC, Liu YC, Yang YG, Gorbach AM. Reconstruction of Thermographic Signals to Map Perforator Vessels in Humans. Quant Infrared Thermogr J 2012; 9:123-133. [PMID: 23667389 PMCID: PMC3650860 DOI: 10.1080/17686733.2012.737157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Thermal representations on the surface of a human forearm of underlying perforator vessels have previously been mapped via recovery-enhanced infrared imaging, which is performed as skin blood flow recovers to baseline levels following cooling of the forearm. We noted that the same vessels could also be observed during reactive hyperaemia tests after complete 5-min occlusion of the forearm by an inflatable cuff. However, not all subjects showed vessels with acceptable contrast. Therefore, we applied a thermographic signal reconstruction algorithm to reactive hyperaemia testing, which substantially enhanced signal-to-noise ratios between perforator vessels and their surroundings, thereby enabling their mapping with higher accuracy and a shorter occlusion period.
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Affiliation(s)
- Wei-Min Liu
- Dept. of Computer Science and Information Engineering, National Chung Cheng University, Taiwan
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Tibiriçá E, Matheus ASM, Nunes B, Sperandei S, Gomes MB. Repeatability of the evaluation of systemic microvascular endothelial function using laser doppler perfusion monitoring: clinical and statistical implications. Clinics (Sao Paulo) 2011; 66:599-605. [PMID: 21655753 PMCID: PMC3152722 DOI: 10.1590/s1807-59322011000400013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 11/01/2011] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE An awareness of the repeatability of biological measures is required to properly design and calculate sample sizes for longitudinal interventional studies. We investigated the day-to-day repeatability of measures of systemic microvascular reactivity using laser Doppler perfusion monitoring. METHODS We performed laser Doppler perfusion monitoring in combination with skin iontophoresis using acetylcholine and sodium nitroprusside as well as post-occlusive reactive and thermal hyperemia twice within two weeks. The repeatability was assessed by calculating the within-subject standard deviations, limits of agreement, typical errors and intra-class correlation coefficients between days 1 and 2. The ratio of the within-subject standard deviation to the mean values obtained on days 1 and 2 (within-subject standard deviation/GM) was used to determine the condition with the best repeatability. RESULTS Twenty-four healthy subjects, aged 24.6 ± 3.8 years, were recruited. The area under the curve of the vasodilatory response to post-occlusive reactivity showed marked variability (within-subject standard deviation/GM = 0.83), while the area under the curve for acetylcholine exhibited less variability (within-subject standard deviation/ GM = 0.52) and was comparable to the responses to sodium nitroprusside and thermal treatment (within-subject standard deviations/GM of 0.67 and 0.56, respectively). The area under the blood flow/time curve for vasodilation during acetylcholine administration required the smallest sample sizes, the area under the blood flow/time curve during post-occlusive reactivity required the largest sample sizes, and the area under the blood flow/time curves of vasodilation induced by sodium nitroprusside and thermal treatment required intermediate sizes. CONCLUSIONS In view of the importance of random error related to the day-to-day repeatability of laser Doppler perfusion monitoring, we propose an original and robust statistical methodology for use in designing prospective clinical studies.
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Beer S, Feihl F, Ruiz J, Juhan-Vague I, Aillaud MF, Wetzel SG, Liaudet L, Gaillard RC, Waeber B. Comparison of skin microvascular reactivity with hemostatic markers of endothelial dysfunction and damage in type 2 diabetes. Vasc Health Risk Manag 2009; 4:1449-58. [PMID: 19337558 PMCID: PMC2663449 DOI: 10.2147/vhrm.s4175] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Aim: Patients with non-insulin-dependent diabetes mellitus (NIDDM) are at increased cardiovascular risk due to an accelerated atherosclerotic process. The present study aimed to compare skin microvascular function, pulse wave velocity (PWV), and a variety of hemostatic markers of endothelium injury [von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (t-PA), tissue factor pathway inhibitor (TFPI), and the soluble form of thrombomodulin (s-TM)] in patients with NIDDM. Methods: 54 patients with NIDDM and 38 sex- and age-matched controls were studied. 27 diabetics had no overt micro- and/or macrovascular complications, while the remainder had either or both. The forearm skin blood flow was assessed by laser-Doppler imaging, which allowed the measurement of the response to iontophoretically applied acetylcholine (endothelium-dependent vasodilation) and sodium nitroprusside (endothelium-independent vasodilation), as well as the reactive hyperemia triggered by the transient occlusion of the circulation. Results: Both endothelial and non-endothelial reactivity were significantly blunted in diabetics, regardless of the presence or the absence of vascular complications. Plasma vWF, TFPI and s-TM levels were significantly increased compared with controls only in patients exhibiting vascular complications. Concentrations of t-PA and PAI-1 were significantly increased in the two groups of diabetics versus controls. Conclusion: In NIDDM, both endothelium-dependent and -independent microvascular skin reactivity are impaired, whether or not underlying vascular complications exist. It also appears that microvascular endothelial dysfunction is not necessarily associated in NIDDM with increased circulating levels of hemostatic markers of endothelial damage known to reflect a hypercoagulable state.
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Affiliation(s)
- Sandra Beer
- Division de Physiopathologie Clinique, Centre Hospitalier Universitaire Vaudois et Université de Lausanne, Lausanne, Switzerland
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Forst T, Hohberg C, Tarakci E, Forst S, Kann P, Pfützner A. Reliability of lightguide spectrophotometry (O2C) for the investigation of skin tissue microvascular blood flow and tissue oxygen supply in diabetic and nondiabetic subjects. J Diabetes Sci Technol 2008; 2:1151-6. [PMID: 19885305 PMCID: PMC2769807 DOI: 10.1177/193229680800200625] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND AIMS Skin microvascular assessment has progressed to an important evaluation in patients with diabetes mellitus. This study was done to evaluate a new device using micro-lightguide spectrophotometry in the assessment of skin microvascular function. MATERIAL AND METHODS Twenty nondiabetic subjects (age 46.6 +/- 14.8 years; mean +/- SD) and 20 diabetic patients (age 59.4 +/- 8.4 years) participated in repeated microvascular measurements using micro-lightguide spectrophotometry. This technique allows simultaneous, noninvasive measurement of microvascular blood flow and hemoglobin oxygenation (SO(2)) at the same anatomical area in different tissue layers. A skin probe was placed on nonhairy skin at the thenar eminence of the left hand for the measurement of SO(2), and the postischemic reactive hyperemia response (PRH) was measured in skin and underlying muscle tissue. RESULTS Repeated measurements in PRH revealed a good correlation at the superficial skin layer (r = 0.97, p < 0.0001) with a coefficient of variation at 9.2 +/- 1.7% and at the superficial muscle layer (r = 0.80, p < 0.0002) with a coefficient of variation at 9.7 +/- 1.5%. A slightly weaker correlation was observed for the SO(2) measurement at the skin layer (r = 0.69 +/- p < 0.0001) with a coefficient of variation at 17.5 +/- 3.8% and at the muscle layer (r = 0.48; p = 0.0016) with a coefficient of variation at 18.1 +/- 10.5%. CONCLUSIONS Lightguide spectrophotometry is an easy, noninvasive, and reliable method for simultaneous measurement of superficial microvascular blood flow by laser Doppler fluxmetry and skin oxygenation by spectrophotometry. Further studies are required to clarify the validity of these measures in special patient populations such as diabetes mellitus with specified microvascular complications.
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Affiliation(s)
- Thomas Forst
- Institute for Clinical Research and Development, Mainz, Germany.
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Abstract
AIMS Endothelin-1 (ET-1) is a potent vasoconstrictor produced by the vascular endothelium. The interactions of ET with the mediators of the sympathetic nervous system and the renin-angiotensin-system in humans are unclear. METHODS We studied the effects of the ETA-selective antagonist BQ-123 and the ETB-selective antagonist BQ-788 (both 10(-10)-10(-8) M) on ET-1 (10(-16)-10(-10) M), angiotensin II (AT, 10(-16)-10(-10) M) and noradrenaline (NA, 10(-16)-10(-10) M) induced vasoconstriction in the human skin microcirculation in vivo in 25 healthy male volunteers using laser Doppler flowmetry and double injection technique. RESULTS BQ-123 caused a dose-dependent vasodilatation (maximum effect: + 949 +/- 84 AUC-PU, P < 0.001), whereas BQ-788 induced mild vasoconstriction (maximum effect: -388 +/- 96 AUC-PU, P < 0.01). In the presence of BQ-123, but not BQ-788, ET-1, AT and NA caused markedly less vasoconstriction at any tested agonist dose; the effect was most pronounced on ET-1 (maximum effect at 10(-14) M: + 814 +/- 93 AUC-PU vs ET alone, P < 0.001), followed by noradrenaline (maximum effect at 10(-16) M: +580 +/- 107 AUC-PU vs NA alone, P < 0.01) and angiotensin II (maximum effect at 10(-14) M: + 493 +/- 111 AUC-PU vs AT alone, P < 0.001). CONCLUSIONS ETA-selective antagonism inhibits vasoconstriction to AT and NA in vivo in healthy subjects. This beneficial effect may be useful for the treatment of patients with cardiovascular disease including hypertension especially in combination therapy with sympatholytic agents and inhibitors of the renin-angiotensin system.
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Affiliation(s)
- R R Wenzel
- Division of Nephrology and Hypertension, Department of Internal Medicine, University Hospital Essen, Essen, Germany.
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Abstract
Capillaries play a critical role in cardiovascular function as the point of exchange of nutrients and waste products between the tissues and circulation. Studies of capillary function in man are limited by access to the vascular bed. However, skin capillaries can readily be studied by the technique of capillaroscopy which enables the investigator to assess morphology, density and blood flow velocity. It is also possible to estimate capillary pressure by direct cannulation using glass micropipettes. This review will describe the techniques used to make these assessments and will outline some of the changes that are seen in health and disease.
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Affiliation(s)
- A C Shore
- Department of Diabetes and Vascular Medicine, School of Postgraduate Medicine and Health Sciences, University of Exeter, EX2 5AX.
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