1
|
Exploitation of blood non-Newtonian properties for ultrasonic measurement of hematocrit. Sci Rep 2021; 11:10208. [PMID: 33986398 PMCID: PMC8119724 DOI: 10.1038/s41598-021-89704-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 04/14/2021] [Indexed: 12/02/2022] Open
Abstract
New processing techniques for manipulating blood and its components at a microfluidic scale are currently implemented. As for extracorporeal circulation, the in-line evaluation and monitoring of blood properties during these microfluidic techniques is a challenging task. Here, we show that the blood hematocrit can be measured non-invasively in a sub-millimeter medical tube using the non-Newtonian behavior of blood velocity profile. This hematocrit measurement is demonstrated on human blood with a simple Doppler ultrasound system. Results show a mean measurement error of 4.6 ± 1.3%Hct for hematocrit up to 52% and for 5 s-long ultrasonic signals. The simplicity and the measurement scale of the approach make it highly valuable for measuring hematocrit in new blood separation techniques. The approach may have an impact on in-vitro blood processing in general.
Collapse
|
2
|
Khalafi M, Alamdari KA, Symonds ME, Nobari H, Carlos-Vivas J. Impact of acute exercise on immediate and following early post-exercise FGF-21 concentration in adults: systematic review and meta-analysis. Hormones (Athens) 2021; 20:23-33. [PMID: 33151509 DOI: 10.1007/s42000-020-00245-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 09/15/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE/OBJECTIVE The aim of this study was to quantify circulating fibroblast growth factor 21 (FGF-21) changes during and immediately after acute exercise and, based on body weight, to identify the subgroups exhibiting the largest response. METHODS The PubMed, Web of Science, and Cochrane Library electronic databases were searched up to December 2019 for studies published in English peer-reviewed journals. Studies that evaluated the effects of acute exercise on FGF-21 concentrations immediately after and 1 and 3 h post-exercise in adults were included. Random effects models were used for analyses, with data reported as standardized mean difference (SMD) and 95% confidence interval, and the risk of heterogeneity was evaluated. Subgroup analysis of subjects with normal weight and obesity/overweight was performed. RESULTS A total of seven studies involving 125 participants (age 35.95 (21-64) years and BMI 25.89 (21.30-35.46) kg/m2) were included. Overall, acute exercise increased FGF-21 (d = 0.18; 95% CI 0.01 to 0.35, p = 0.02) and this remained for 1 h post-exercise FGF-21 (d = 0.59; 95% CI 0.33 to 0.86, p = 0.001). Three hours after exercise, FGF-21 was restored to near baseline values (d = - 0.05; 95% CI - 0.34 to 0.22, p = 0.68). Acute exercise raised FGF-21 concentrations in normal weight participants (d = 0.57, p = 0.001) and tended to increase in overweight and obese participants (d = 0.79, p = 0.05) 1 h post-exercise. CONCLUSION Acute exercise increases circulating FGF-21, irrespective of body weight.
Collapse
Affiliation(s)
- Mousa Khalafi
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Guilan, Rasht, 4199613776, Iran.
| | - Karim Azali Alamdari
- Department of Sport Sciences, Azarbaijan Shahid Madani University, Tabriz, 5375171379, Iran.
| | - Michael E Symonds
- The Early Life Research Unit, Division of Child Health, Obstetrics and Gynaecology, and Nottingham Digestive Disease Centre and Biomedical Research Centre, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Hadi Nobari
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran
| | - Jorge Carlos-Vivas
- Health, Economy, Motricity and Education Research Group (HEME), Faculty of Sport Sciences, University of Extremadura, 10003, Caceres, Spain
| |
Collapse
|
3
|
Guan A, Richardson S, Hinckley S. Optical coherence tomography modeling incorporating scattering, absorption, and multiple reflections. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2020; 37:391-398. [PMID: 32118922 DOI: 10.1364/josaa.377121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
A direct scattering optical coherence tomography forward model was developed to simulate A-scans for both idealized and real light sources on an arbitrary given sample structure. Previous models neglected absorption, scattering, and multiple reflections at interfacial layers, and so two extended models were developed to investigate the impact of these processes. The first model uses the Beer-Lambert law to incorporate both absorption and scattering optical processes, and the second model uses a recursive form to model multiple reflections. These models were tested on a structure representative of a multilayered skin sample. The results show that the absorption and scattering processes have significant impact on the height of the peaks in the simulated A-scans. Conversely, the incorporation of multiple reflections has very little impact on the height of these peaks. Neither of the above processes has any impact on the locations of the A-scan peaks, which are associated with the sample interfaces between layers.
Collapse
|
4
|
Ma J, Chen B, Li D, Zhang Y, Ying Z. Glucose in Conjunction with Multiple Laser Pulses on Laser Treatment of Port-wine Stain: An in vivo Study. Lasers Med Sci 2018. [PMID: 29542044 DOI: 10.1007/s10103-018-2481-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Port-wine stain (PWS) birthmark is a congenital microvascular malformation of the skin. A 1064-nm Nd:YAG laser can achieve a deeper treatment, but the weak absorption by blood limits its clinical application. Multiple laser pulses (MLPs) are a potential solution to enhance the curative effect of a Nd:YAG laser. To reduce the pulse number (pn) required for the thermal destruction of the blood vessel, the effect of glucose in conjunction with MLP was investigated. In vivo experiments were performed on a dorsal skin chamber model. Different concentrations (20, 25, 30, and 40%) of glucose were applied to the sub-dermal side of the hamster skin before laser irradiation. Identical vessels with diameters of 200 ± 30 and 110 ± 20 μm were chosen as representatives of typical PWS vessels. Instant thermal responses of the blood vessel were recorded by a high-speed camera. The required pn for blood vessel damage was compared with that without glucose pretreatment. Results showed that the use of glucose with a concentration of 20% combined with MLP Nd:YAG laser to damage blood vessels is more appropriate because severe hemorrhage or carbonization easily appeared in blood vessels at higher glucose concentration of 25, 30, and 40%. When 20% glycerol is pretreated on the sub-dermal hamster skin, the required pn for blood vessel damage can be significantly decreased for different power densities. For example, pn can be reduced by 40% when the power density is 57 J/cm2. In addition, generation of cavitation and bubbles in blood vessels is difficult upon pretreatment with glucose. The combination of glucose with MLP Nd:YAG laser could be an effective protocol for reducing the pn required for blood vessel damage. Randomized controlled trial (RCT) and human trials will be conducted in the future.
Collapse
Affiliation(s)
- Jun Ma
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China
| | - Bin Chen
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China.
| | - Dong Li
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China
| | - Yue Zhang
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China
| | - Zhaoxia Ying
- State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China.
| |
Collapse
|
5
|
Kinnunen M, Bykov AV, Tuorila J, Haapalainen T, Karmenyan AV, Tuchin VV. Optical clearing at cellular level. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:71409. [PMID: 24615672 DOI: 10.1117/1.jbo.19.7.071409] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 02/12/2014] [Indexed: 06/03/2023]
Abstract
Strong light scattering in tissues and blood reduces the usability of many optical techniques. By reducing scattering, optical clearing enables deeper light penetration and improves resolution in several optical imaging applications. We demonstrate the usage of optical tweezers and elastic light scattering to study optical clearing [one of the major mechanisms-matching of refractive indices (RIs)] at the single particle and cell level. We used polystyrene spheres and human red blood cells (RBCs) as samples and glycerol or glucose water solutions as clearing agents. Optical tweezers kept single microspheres and RBCs in place during the measurement of light scattering patterns. The results show that optical clearing reduces the scattering cross section and increases g. Glucose also decreased light scattering from a RBC. Optical clearing affected the anisotropy factor g of 23.25-μm polystyrene spheres, increasing it by 0.5% for an RI change of 2.2% (20% glycerol) and 0.3% for an RI change of 1.1% (13% glucose).
Collapse
Affiliation(s)
- Matti Kinnunen
- University of Oulu, Optoelectronics and Measurement Techniques Laboratory, P.O. Box 4500, Oulu 90014, Finland
| | - Alexander V Bykov
- University of Oulu, Optoelectronics and Measurement Techniques Laboratory, P.O. Box 4500, Oulu 90014, Finland
| | - Juho Tuorila
- University of Oulu, Optoelectronics and Measurement Techniques Laboratory, P.O. Box 4500, Oulu 90014, Finland
| | - Tomi Haapalainen
- University of Oulu, Optoelectronics and Measurement Techniques Laboratory, P.O. Box 4500, Oulu 90014, Finland
| | - Artashes V Karmenyan
- National Yang-Ming University, Biophotonics and Molecular Imaging Research Center, Taipei 11221, Taiwan
| | - Valery V Tuchin
- University of Oulu, Optoelectronics and Measurement Techniques Laboratory, P.O. Box 4500, Oulu 90014, FinlandcSaratov State University, Research-Educational Institute of Optics and Biophotonics, Saratov 410012, RussiadInstitute of Precise Mechanics and Co
| |
Collapse
|
6
|
Bukowska DM, Derzsi L, Tamborski S, Szkulmowski M, Garstecki P, Wojtkowski M. Assessment of the flow velocity of blood cells in a microfluidic device using joint spectral and time domain optical coherence tomography. OPTICS EXPRESS 2013; 21:24025-24038. [PMID: 24104312 DOI: 10.1364/oe.21.024025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Although Doppler optical coherence tomography techniques have enabled the imaging of blood flow in mid-sized vessels in biological tissues, the generation of velocity maps of capillary networks remains a challenge. To better understand the origin and information content of the Doppler signal from small vessels and limitations of such measurements, we used joint spectral and time domain optical coherence tomography to monitor the flow in a model, semitransparent microchannel device. The results obtained for Intralipid, whole blood, as well as separated red blood cells indicate that the technique is suitable to record velocity profiles in vitro, in a range of microchannel configurations.
Collapse
|
7
|
Xu X, Geng J, Liu G, Chen Z. Evaluation of optical coherence tomography for the measurement of the effects of activators and anticoagulants on the blood coagulation in vitro. IEEE Trans Biomed Eng 2013; 60:2100-6. [PMID: 23392340 PMCID: PMC3888882 DOI: 10.1109/tbme.2013.2245329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Optical properties of human blood during coagulation were studied using optical coherence tomography (OCT) and the parameter of clotting time derived from the 1/e light penetration depth (d(1/e)) versus time was developed in our previous work. In this study, in order to know if a new OCT test can characterize the blood-coagulation process under different treatments in vitro, the effects of two different activators (calcium ions and thrombin) and anticoagulants, i.e., acetylsalicylic acid (ASA, a well-known drug aspirin) and melagatran (a direct thrombin inhibitor), at various concentrations are evaluated. A swept-source OCT system with a 1300 nm center wavelength is used for detecting the blood-coagulation process in vitro under a static condition. A dynamic study of d1/e reveals a typical behavior due to coagulation induced by both calcium ions and thrombin, and the clotting time is concentration-dependent. Dose-dependent ASA and melagatran prolong the clotting times. ASA and melagatran have different effects on blood coagulation. As expected, melagatran is much more effective than ASA in anticoagulation by the OCT measurements. The OCT assay appears to be a simple method for the measurement of blood coagulation to assess the effects of activators and anticoagulants, which can be used for activator and anticoagulant screening.
Collapse
Affiliation(s)
- Xiangqun Xu
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China ()
| | - Jinhai Geng
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China ()
| | - Gangjun Liu
- Beckman Laser Institute, Department of Biomedical Engineering, University of California, Irvine, CA 92617 USA ()
| | - Zhongping Chen
- Beckman Laser Institute, Department of Biomedical Engineering, University of California, Irvine, CA 92617 USA ()
| |
Collapse
|
8
|
He R, Wei H, Gu H, Zhu Z, Zhang Y, Guo X, Cai T. Effects of optical clearing agents on noninvasive blood glucose monitoring with optical coherence tomography: a pilot study. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:101513. [PMID: 23223989 DOI: 10.1117/1.jbo.17.10.101513] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Recently, the capability of optical coherence tomography (OCT) has been demonstrated for noninvasive blood glucose monitoring. In this work, we investigate the administration of chemical agents onto human skin tissue to increase the transparency of the surface of the skin, as a means of improving the capability of OCT imaging for clinically relevant applications. Eight groups of experiments were proposed, in which different optical clearing agents (OCA) were used. The results indicate that, when properly used, some OCAs perform well in promoting the capability of OCT for noninvasive blood glucose monitoring. Among the four kinds of OCA we used, 50% v/v glycerol solute turns out to be the best enhancer. Compared with the results of the experiments in which no OCA was used, when 50% glycerol was applied onto the human skin topically, the correlation coefficient between the OCT signal slope (OCTSS) and blood glucose concentration (BGC) was improved by 7.1% on average, and the lag time between changes in the OCTSS and BGC was cut by 8 min on average. The results of 10 w/v mannitol were also good, but not as pronounced.
Collapse
Affiliation(s)
- Ruoyu He
- Key Laboratory of Laser Life Science of Ministry of Education of China, South China Normal University, Guangzhou 510631, Guangdong, China
| | | | | | | | | | | | | |
Collapse
|
9
|
Fu F, Xu X, Geng J. Characterization of flowing blood optical property under various fibrinogen levels using optical coherence tomography. IEEE Trans Biomed Eng 2012; 59:2613-8. [PMID: 22801485 DOI: 10.1109/tbme.2012.2207899] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The feasibility of characterization of human blood fibrinogen levels using optical coherence tomography (OCT) was investigated. Three groups of blood samples were reconstituted of red blood cells: 1) phosphate-buffered saline; 2) plasma with its intrinsic fibrinogen removed and commercial fibrinogen added; and 3) native plasma with various fibrinogen levels (0-12 g/L). OCT signal slope (OCTSS) of blood was extracted from OCT depth-reflectivity profiles. Effects of hematocrit (HCT) and blood flow on OCTSS of the blood under various fibrinogen concentrations were also studied. The results of blood flowing at 5 mm/s showed that OCTSS of all the three groups at HCT of 40% decreases with the increasing fibrinogen concentration up to a certain level, i. e., >8, 6, and 4 g/L for groups 1, 2, and 3, respectively. The blood of group 2 at HCTs of 30%, 40%, and 50% had a rapid decrease in OCTSS in the range of fibrinogen concentration of 0-2, 0-6, and 0-10 g/L, respectively. OCTSS value of blood flowing at 2.5 mm/s was lower than that at 5 mm/s at each fibrinogen concentration. In conclusion, OCTSS has a strong correlation with plasma fibrinogen concentration, and has the potential to identify the abnormal level of human blood fibrinogen.
Collapse
Affiliation(s)
- Feifei Fu
- School of Science, Zhejiang Sci-Tech University, Hangzhou, China.
| | | | | |
Collapse
|
10
|
Nam KH, Jeong B, Jung IO, Ha H, Kim KH, Lee SJ. Measurement of anisotropic reflection of flowing blood using optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:120502. [PMID: 22191907 DOI: 10.1117/1.3660299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Light reflectance of blood is a complex phenomenon affected by hematocrit and red blood cell (RBC) aggregation (rouleaux formation). According to the hypothesis that RBC rouleaux are aligned with the direction of blood flow, the spatial alignment of RBC rouleaux, as well as their size and quantity in the blood, may also affect light reflectance. The present study aims to investigate the effect of the spatial alignment and distribution of RBC rouleaux on light reflection using optical coherence tomography (OCT). Blood flow velocity and reflectance profiles in a rat jugular-femoral bypass loop were simultaneously measured using a Doppler swept-source OCT system at various incident angles from -30 to +30 deg. The reflectance profiles of flowing blood show nonmonotonous decay with a local negative peak at the center of the tube. The profiles vary depending on the incident angle. This angular dependence is stronger at a higher angle of incidence. The anisotropic reflectance of flowing blood is consistent with the hypothesis on the spatial alignment of RBC rouleaux.
Collapse
|
11
|
Xu X, Lin J, Fu F. Optical coherence tomography to investigate optical properties of blood during coagulation. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:096002. [PMID: 21950916 DOI: 10.1117/1.3615667] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study investigates the optical properties of human blood during the coagulation process under statics using optical coherence tomography (OCT). OCT signal slope (OCTSS) and 1∕e light penetration depth (d(1∕e)) were obtained from the profiles of reflectance versus depth. Results showed that both OCTSS and d(1∕e) were able to sensitively differentiate various stages of blood properties during coagulating. After 1 h clotting, OCTSS decreased by 47.0%, 15.0%, 13.7%, and 8.5% and d(1∕e) increased by 34.7%, 29.4%, 24.3%, and 22.9% for the blood samples at HCT of 25%, 35%, 45%, and 55%, respectively. The slope of d(1∕e) versus time (S(r), ×10(-4) mm∕s), associated with clot formation rate decreased from 6.0 ± 0.3, 3.7 ± 0.5 to 2.3 ± 0.4 with the increasing of HCT from 35%, 45%, to 55%. The clotting time (t(c)) from the d(1∕e) evolution curves was estimated to be 1969 ± 92 s, 375 ± 12 s, 455 ± 11 s, and 865 ± 47 s for the blood of 25%, 35%, 45%, and 55%. This study demonstrates that the parameters (t(c) and S(r)) from the variations in d(1∕e) had better sensitivity and smaller standard deviation. Furthermore, blood hematocrit affecting backscattering properties of blood during coagulation was capable of being discerned by OCT parameters. It is concluded that OCT is a potential technique to quantify and follow the liquid-gel transition of blood during clotting.
Collapse
Affiliation(s)
- Xiangqun Xu
- Zhejiang Sci-Tech University, School of Science, Hangzhou 310018, China.
| | | | | |
Collapse
|
12
|
Xu X, Yu L, Chen Z. Velocity variation assessment of red blood cell aggregation with spectral domain Doppler optical coherence tomography. Ann Biomed Eng 2010; 38:3210-7. [PMID: 20473568 PMCID: PMC2940018 DOI: 10.1007/s10439-010-0066-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 05/05/2010] [Indexed: 11/26/2022]
Abstract
We propose spectral domain Doppler optical coherence tomography (SD-D-OCT) to qualitatively measure red blood cell aggregation. Variance/standard deviation (SD) of the Doppler frequency spectrum in Doppler variance imaging of flowing blood under shearing conditions was developed as a new aggregation index. In in vitro microchannel-flow experiments, porcine blood at various hematocrits with aggregation characteristics induced by dextran 500 or at the presence of plasma fibrinogen was measured by a SD-D-OCT system with a spectrum centered at 1310 nm. The effects of shear rate, hematocrit, aggregation level on the SD values were investigated. The results demonstrate that Doppler variance imaging using the SD value was capable of differentiating the normal and the aggregated blood with hematocrits of 30-55% flowing at a shear rate of 40-60 s(-1). The SD value was found to be nonsignificant hematocrit-dependent. It is also a sensitive and repeatable aggregation index for comparison between nonaggregated and aggregated blood samples.
Collapse
Affiliation(s)
- Xiangqun Xu
- School of Science, Zhejiang Sci-Tech University, Hangzhou 310018, China.
| | | | | |
Collapse
|
13
|
Xu X, Ahn YC, Chen Z. Feasibility of Doppler variance imaging for red blood cell aggregation characterization. JOURNAL OF BIOMEDICAL OPTICS 2009; 14:060507. [PMID: 20059238 PMCID: PMC2917459 DOI: 10.1117/1.3275464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 08/22/2009] [Accepted: 10/28/2009] [Indexed: 05/28/2023]
Abstract
An abnormal level of red blood cell (RBC) aggregation is a clinical condition associated with many pathologies. Our purpose is to investigate the feasibility of spectral domain phase-resolved optical Doppler tomography incorporated with Doppler variance imaging to characterize RBC aggregation in flowing blood. Variance/standard deviation (SD) of the Doppler frequency spectrum of porcine blood flowing through a glass tube (diameter 300 microm) at 4.7 mms is measured. For nonaggregating RBCs with hematocrits of 20, 40, and 60%, the mean centerline SD values were 34.2+/-1.2, 47.8+/-1.0, and 47.2+/-0.5, respectively. After dextran 500 induction, the SD value decreased significantly to 29.9+/-0.7, 37.9+/-3.0, and 40.1+/-0.6 (P<0.01) in the aggregated blood, respectively. The results demonstrate that Doppler variance imaging using the SD value is capable of differentiating normal and aggregated blood.
Collapse
|
14
|
Popescu DP, Sowa MG. Characteristics of time-domain optical coherence tomography profiles generated from blood–saline mixtures. Phys Med Biol 2009; 54:4759-75. [DOI: 10.1088/0031-9155/54/15/008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|