Remote photoplethysmography for skin perfusion monitoring using narrowband illumination

2019 ◽  
Author(s):  
Zbignevs Marcinkevics ◽  
Uldis Rubins ◽  
Alise Aglinska ◽  
A. Caica ◽  
Andris Grabovskis
Keyword(s):  
Skin Perfusion ◽  
Remote Photoplethysmography

Heart-Rate Evaluation Using Remote Photoplethysmography – A Case Study

2020 ◽  
Author(s):  
Yajat Gupta ◽  
Anureet Kaur ◽  
Aman Arora ◽  
Sahil Kapoor ◽  
Megha Gupta
Keyword(s):  
Heart Rate ◽  
Remote Photoplethysmography ◽  
Rate Evaluation

scholarly journals Hallucal thenar index: A new index to detect peripheral arterial disease using laser speckle flowgraphy

Vascular ◽  
2020 ◽  
pp. 170853812093893
Author(s):  
Kazuhiro Tsunekawa ◽  
Fumio Nagai ◽  
Tamon Kato ◽  
Ikkei Takashimizu ◽  
Daisuke Yanagisawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Peripheral Arterial Disease ◽  
Operating Characteristic ◽  
Ankle Brachial Index ◽  
Arterial Disease ◽  
Laser Speckle ◽  
Laser Speckle Flowgraphy ◽  
Skin Perfusion ◽  
Peripheral Arterial ◽  
Cutaneous Blood

Objectives Laser speckle flowgraphy is a technology using reflected scattered light for visualization of blood distribution, which can be used to measure relative velocity of blood flow easily without contact with the skin within a short time. It was hypothesized that laser speckle flowgraphy may be able to identify foot ischemia. This study was performed to determine whether laser speckle flowgraphy could distinguish between subjects with and without peripheral arterial disease. Materials and methods All subjects were classified based on clinical observations using the Rutherford classification: non-peripheral arterial disease, class 0; peripheral arterial disease group, class 2–5. Rutherford class 6 was one of the exclusion criteria. Laser speckle flowgraphy measured the beat strength of skin perfusion as an indicator of average dynamic cutaneous blood flow change synchronized with the heartbeat. The beat strength of skin perfusion indicates the strength of the heartbeat on the skin, and the heartbeat strength calculator in laser speckle flowgraphy uses the blood flow data to perform a Fourier transform to convert the temporal changes in blood flow to a power spectrum. A total of 33 subjects with peripheral arterial disease and 40 subjects without peripheral arterial disease at a single center were prospectively examined. Laser speckle flowgraphy was used to measure hallucal and thenar cutaneous blood flow, and the measurements were repeated three times. The hallucal and thenar index was defined as the ratio of beat strength of skin perfusion value on hallux/beat strength of skin perfusion value on ipsilateral thenar eminence. The Mann–Whitney U-test was used to compare the median values of hallucal and thenar index and ankle brachial index between the two groups. A receiver operating characteristic curve for hallucal and thenar index of beat strength of skin perfusion was plotted, and a cutoff point was set. The correlation between hallucal and thenar index of beat strength of skin perfusion and ankle brachial index was explored in all subjects, the hemodialysis group, and the non-hemodialysis (non-hemodialysis) group. Results The median value of the hallucal and thenar index of beat strength of skin perfusion was significantly different between subjects with and without peripheral arterial disease (0.27 vs. 0.87, respectively; P <  0.001). The median value of ankle brachial index was significantly different between subjects with and without peripheral arterial disease (0.8 vs. 1.1, respectively; P <  0.001). Based on the receiver operating characteristic of hallucal and thenar index, the cutoff was 0.4416 and the sensitivity, specificity, positive predictive value, and negative predictive value were 68.7%, 95%, 91.7%, and 77.6%, respectively. The correlation coefficients of all subjects, the hemodialysis group, and the non-hemodialysis group were 0.486, 0.102, and 0.743, respectively. Conclusions Laser speckle flowgraphy is a noninvasive, rapid, and widely applicable method. Laser speckle flowgraphy using hallucal and thenar index would be helpful to determine the differences between subjects with and without peripheral arterial disease. The correlation between hallucal and thenar index of beat strength of skin perfusion and ankle brachial index indicated that this index was especially useful in the non-hemodialysis group.

Skin perfusion pressure for predicting access-related hand ischemia following arteriovenous fistula surgery based on the brachial artery

2021 ◽  
pp. 112972982199398
Author(s):  
Miju Bae ◽  
Sung Woon Chung ◽  
Chung Won Lee ◽  
Up Huh ◽  
Moran Jin ◽  
...  
Keyword(s):  
Arteriovenous Fistula ◽  
Sensitivity And Specificity ◽  
Brachial Artery ◽  
Perfusion Pressure ◽  
Characteristic Curve ◽  
Major Complication ◽  
Clinical Predictors ◽  
Skin Perfusion ◽  
Hand Ischemia ◽  
Skin Perfusion Pressure

Background: Access-related hand ischemia (ARHI) is a major complication of arteriovenous fistula (AVF). This study aimed to assess the predictive efficacy of skin perfusion pressure (SPP) measurement for ARHI by examining the relationship between SPP and ARHI development and progression after AVF surgery. Methods: Twenty-five patients (16 men and 9 women) who underwent AVF surgery based on the brachial artery between January 2018 and December 2018 were included. The pre- and postoperative SPP values were measured on the day of surgery. ARHI occurrence and severity were measured within 3 days and at 6 months after surgery. Receiver operating characteristic curve analysis was used to evaluate the prediction model of ARHI, and the cutoff points for the calculated coefficients were determined. Results: There was a significant correlation between the occurrence of immediate ARHI and the SPP gradient ( p = 0.024). An SPP gradient value >50 mmHg had sensitivity and specificity values of 53.85% and 91.67%, respectively, in predicting the occurrence of immediate ARHI. A postoperative SPP <48 mmHg was significantly correlated with the occurrence of 6-month ARHI ( p = 0.005), with sensitivity and specificity values of 71.43% and 83.33%, respectively. Conclusion: The SPP gradient and postoperative SPP values may be effective clinical predictors of ARHI occurring immediately and 6 months after surgery, respectively, with high specificity. These findings could allow clinicians to diagnose and begin early interventions to help prevent ischemic tissue damage in hemodialysis patients following AVF surgery.

Remote Photoplethysmography with An EEMD-MCCA Method Robust Against Spatially Uneven Illuminations

2021 ◽  
pp. 1-1
Author(s):  
Rencheng Song ◽  
Jiji Li ◽  
Minda Wang ◽  
Juan Cheng ◽  
Chang Li ◽  
...  
Keyword(s):  
Remote Photoplethysmography

scholarly journals Laser Doppler blood flowmeter as a useful instrument for the early detection of lower extremity peripheral arterial disease in hemodialysis patients: an observational study

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Takeo Ishii ◽  
Shizuka Takabe ◽  
Yuki Yanagawa ◽  
Yuko Ohshima ◽  
Yasuhiro Kagawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Peripheral Arterial Disease ◽  
Early Stage ◽  
Arterial Disease ◽  
Hemodialysis Patients ◽  
Laser Doppler ◽  
Doppler Flowmetry ◽  
Skin Perfusion ◽  
Dorsal Area ◽  
Peripheral Arterial

Abstract Background A simpler method for detecting atherosclerosis obliterans is required in the clinical setting. Laser Doppler flowmetry (LDF) is easy to perform and can accurately detect deterioration in skin perfusion. We performed LDF for hemodialysis patients to determine the correlations between blood flow in the lower limbs and peripheral arterial disease (PAD). Methods This retrospective study included 128 hemodialysis patients. Patients were categorized into the non-PAD group (n = 106) and PAD group (n = 22), 14 early stage PAD patients were included in the PAD group. We conducted LDF for the plantar area and dorsal area of the foot and examined skin perfusion pressure (SPP) during dialysis. Results SPP-Dorsal Area values were 82.1 ± 22.0 mmHg in the non-PAD, and 59.1 ± 20.3 mmHg in PAD group, respectively (p < 0.05). The LDF-Plantar blood flow (Qb) values were 32.7 ± 15.5 mL/min in non-PAD group and 21.5 ± 11.3 mL/min in PAD group (p < 0.001). A total of 21 non-PAD patients underwent LDF before and during dialysis. The LDF-Plantar-Qb values were 36.5 ± 17.6 mL/min before dialysis and 29.6 ± 17.7 mL/min after dialysis (p < 0.05). We adjusted SPP and LDF for PAD using logistic regression, SPP-Dorsal-Area and LDF-P were significantly correlated with PAD (p < 0.05). The receiver-operating characteristic curve analysis indicated cut-off values of 20.0 mL/min for LDF-Plantar-Qb during dialysis. Conclusion LDF is a simple technique for sensitive detection of early-stage PAD. This assessment will help physicians identify early-stage PAD, including Fontaine stage II in clinical practice, thereby allowing prompt treatment.

Effect of Liposuction on Skin Perfusion

2002 ◽  
Vol 110 (7) ◽  
pp. 1748-1751 ◽  
Author(s):  
Subhas C. Gupta ◽  
Kayvan T. Khiabani ◽  
Linda L. Stephenson ◽  
William A. Zamboni
Keyword(s):  
Skin Perfusion

Vasodilator effect and mechanism of action of vascular endothelial growth factor in skin vasculature

2004 ◽  
Vol 286 (3) ◽  
pp. H946-H954 ◽  
Author(s):  
Homa Ashrafpour ◽  
Ning Huang ◽  
Peter C. Neligan ◽  
Christopher R. Forrest ◽  
Patrick D. Addison ◽  
...  
Keyword(s):  
Skin Flap ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Skin Flaps ◽  
Skin Perfusion ◽  
Potent Vasodilator ◽  
Or Gene ◽  
Endothelial Growth Factor ◽  
Endothelial Nitric Oxide ◽  
First Time

Various laboratories have reported that local subcutaneous or subdermal injection of VEGF165 at the time of surgery effectively attenuated ischemic necrosis in rat skin flaps, but the mechanism was not studied and enhanced angiogenesis was implicated. In the present study, we used the clinically relevant isolated perfused 6 × 16-cm pig buttock skin flap model to 1) test our hypothesis that VEGF165 is a potent vasodilator and acute VEGF165 treatment increases skin perfusion; and 2) investigate the mechanism of VEGF165-induced skin vasorelaxation. We observed that VEGF165 (5 × 10–16–5 × 10–11 M) elicited a concentration-dependent decrease in perfusion pressure (i.e., vasorelaxation) in skin flaps preconstricted with a submaximal concentration of norepinephrine (NE), endothelin-1, or U-46619. The VEGF165-induced skin vasorelaxation was confirmed using a dermofluorometry technique for assessment of skin perfusion. The vasorelaxation potency of VEGF165 in NE-preconstricted skin flaps (pD2 = 13.57 ± 0.31) was higher ( P < 0.05) than that of acetylcholine (pD2 = 7.08 ± 0.24). Human placental factor, a specific VEGF receptor-1 agonist, did not elicit any vasorelaxation effect. However, a specific antibody to VEGF receptor-2 (1 μg/ml) or a specific VEGF receptor-2 inhibitor (5 × 10–6 M SU-1498) blocked the vasorelaxation effect of VEGF165 in NE-preconstricted skin flaps. These observations indicate that the potent vasorelaxation effect of VEGF165 in the skin vasculature is initiated by the activation of VEGF receptor-2. Furthermore, using pharmacological probes, we observed that the postreceptor signaling pathways of VEGF165-induced skin vasorelaxation involved activation of phospholipase C and protein kinase C, an increase in inositol 1,4,5-trisphosphate activity, release of the intra-cellular Ca2+ store, and synthesis/release of endothelial nitric oxide, which predominantly triggered the effector mechanism of VEGF165-induced vasorelaxation. This information provides, for the first time, an important insight into the mechanism of VEGF165 protein or gene therapy in the prevention/treatment of ischemia in skin flap surgery and skin ischemic diseases.

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