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Chayer B, Allard L, Qin Z, Garcia-Duitama J, Roger L, Destrempes F, Cailhier JF, Denault A, Cloutier G. Pilot clinical study of quantitative ultrasound spectroscopy measurements of erythrocyte aggregation within superficial veins. Clin Hemorheol Microcirc 2020; 74:109-126. [PMID: 31476146 PMCID: PMC7242846 DOI: 10.3233/ch-180541] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND: An enhanced inflammatory response is a trigger to the production of blood macromolecules involved in abnormally high levels of erythrocyte aggregation. OBJECTIVE: This study aimed at demonstrating for the first time the clinical feasibility of a non-invasive ultrasound-based erythrocyte aggregation quantitative measurement method for potential application in critical care medicine. METHODS: Erythrocyte aggregation was evaluated using modeling of the backscatter coefficient with the Structure Factor Size and Attenuation Estimator (SFSAE). SFSAE spectral parameters W (packing factor) and D (mean aggregate diameter) were measured within the antebrachial vein of the forearm and tibial vein of the leg in 50 healthy participants at natural flow and reduced flow controlled by a pressurized bracelet. Blood samples were also collected to measure erythrocyte aggregation ex vivo with an erythroaggregometer (parameter S10). RESULTS: W and Din vivo measurements were positively correlated with the ex vivoS10 index for both measurement sites and shear rates (correlations between 0.35–0.81, p < 0.05). Measurement at low shear rate was found to increase the sensitivity and reliability of this non-invasive measurement method. CONCLUSIONS: We behold that the SFSAE method presents systemic measures of the erythrocyte aggregation level, since results on upper and lower limbs were highly correlated.
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Affiliation(s)
- Boris Chayer
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Louise Allard
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Zhao Qin
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Julian Garcia-Duitama
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada.,Institute of Biomedical Engineering, University of Montreal, Montréal, QC, Canada
| | - Laurence Roger
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - François Destrempes
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | | | - André Denault
- Montreal Heart Institute, University of Montreal Hospital, and Department of Anesthesiology, University of Montreal, Montréal, QC, Canada
| | - Guy Cloutier
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada.,Institute of Biomedical Engineering, University of Montreal, Montréal, QC, Canada.,Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montreal, QC, Canada
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Gyawali P, Ziegler D, Cailhier JF, Denault A, Cloutier G. Quantitative Measurement of Erythrocyte Aggregation as a Systemic Inflammatory Marker by Ultrasound Imaging: A Systematic Review. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:1303-1317. [PMID: 29661483 DOI: 10.1016/j.ultrasmedbio.2018.02.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/21/2018] [Accepted: 02/28/2018] [Indexed: 06/08/2023]
Abstract
This systematic review is aimed at answering two questions: (i) Is erythrocyte aggregation a useful biomarker in assessing systemic inflammation? (ii) Does quantitative ultrasound imaging provide the non-invasive option to measure erythrocyte aggregation in real time? The search was executed through bibliographic electronic databases CINAHL, EMB Review, EMBASE, MEDLINE, PubMed and the grey literature. The majority of studies correlated elevated erythrocyte aggregation with inflammatory blood markers for several pathologic states. Some studies used "erythrocyte aggregation" as an established marker of systemic inflammation. There were limited but promising articles regarding the use of quantitative ultrasound spectroscopy to monitor erythrocyte aggregation. Similarly, there were limited studies that used other ultrasound techniques to measure systemic inflammation. The quantitative measurement of erythrocyte aggregation has the potential to be a routine clinical marker of inflammation as it can reflect the cumulative inflammatory dynamics in vivo, is relatively simple to measure, is cost-effective and has a rapid turnaround time. Technologies like quantitative ultrasound spectroscopy that can measure erythrocyte aggregation non-invasively and in real time may offer the advantage of continuous monitoring of the inflammation state and, thus, may help in rapid decision making in a critical care setup.
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Affiliation(s)
- Prajwal Gyawali
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada
| | - Daniela Ziegler
- Documentation Center, University of Montreal Hospital, Montréal, Québec, Canada
| | - Jean-François Cailhier
- University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada; Department of Medicine, University of Montreal, Montréal, Québec, Canada
| | - André Denault
- University of Montreal Hospital, Montreal, Québec, Canada; Montreal Heart Institute, Montreal, Québec, Canada; Department of Anesthesiology, University of Montreal, Montréal, Québec, Canada
| | - Guy Cloutier
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada; Department of Radiology, Radio-Oncology and Nuclear Medicine, Montréal, Québec, Canada; Institute of Biomedical Engineering, University of Montreal, Montréal, Québec, Canada.
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Nam KH, Paeng DG. In vivo observation of the hypo-echoic "black hole" phenomenon in rat arterial bloodstream: a preliminary Study. ULTRASOUND IN MEDICINE & BIOLOGY 2014; 40:1619-1628. [PMID: 24785440 DOI: 10.1016/j.ultrasmedbio.2014.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 12/26/2013] [Accepted: 01/27/2014] [Indexed: 06/03/2023]
Abstract
The "black hole," a hypo-echoic hole at the center of the bloodstream surrounded by a hyper-echoic zone in cross-sectional views, has been observed in ultrasound backscattering measurements of blood with red blood cell aggregation in in vitro studies. We investigated whether the phenomenon occurs in the in vivo arterial bloodstream of rats using a high-frequency ultrasound imaging system. Longitudinal and cross-sectional ultrasound images of the rat common carotid artery (CCA) and abdominal aorta were obtained using a 40-MHz ultrasound system. A high-frame-rate retrospective imaging mode was employed to precisely examine the dynamic changes in blood echogenicity in the arteries. When the imaging was performed with non-invasive scanning, blood echogenicity was very low in the CCA as compared with the surrounding tissues, exhibiting no hypo-echoic zone at the center of the vessel. Invasive imaging of the CCA by incising the skin and subcutaneous tissues at the imaging area provided clearer and brighter blood echo images, showing the "black hole" phenomenon near the center of the vessel in longitudinal view. The "black hole" was also observed in the abdominal aorta under direct imaging after laparotomy. The aortic "black hole" was clearly observed in both longitudinal and cross-sectional views. Although the "black hole" was always observed near the center of the arteries during the diastolic phase, it dissipated or was off-center along with the asymmetric arterial wall dilation at systole. In conclusion, we report the first in vivo observation of the hypo-echoic "black hole" caused by the radial variation of red blood cell aggregation in arterial bloodstream.
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Affiliation(s)
- Kweon-Ho Nam
- Department of Ocean System Engineering, Jeju National University, Jeju, South Korea
| | - Dong-Guk Paeng
- Department of Ocean System Engineering, Jeju National University, Jeju, South Korea; Interdisciplinary Postgraduate Program in Biomedical Engineering, Jeju National University, Jeju, South Korea.
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Koehler MJ, Lange-Asschenfeldt S, Kaatz M. Non-invasive imaging techniques in the diagnosis of skin diseases. ACTA ACUST UNITED AC 2011; 5:425-40. [DOI: 10.1517/17530059.2011.599064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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5
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Paeng DG, Nam KH, Shung KK. Cyclic and radial variation of the echogenicity of blood in human carotid arteries observed by harmonic imaging. ULTRASOUND IN MEDICINE & BIOLOGY 2010; 36:1118-24. [PMID: 20620699 DOI: 10.1016/j.ultrasmedbio.2010.03.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 03/25/2010] [Accepted: 03/29/2010] [Indexed: 05/24/2023]
Abstract
To better understand the characteristics of erythrocyte aggregation in flowing blood, echogenicity variation in blood was observed both in vitro and in vivo. However, few noninvasive observations of blood echogenicity variation during the cardiac cycle in human arteries have been reported. In the present study, to reduce the dynamic range between the blood vessel lumen and the surrounding tissue, coded harmonic images were acquired from human carotid arteries using a GE LOGIQ 700 Expert system (GE, Milwaukee, WI, USA) with an M12L probe, which enabled the noninvasive detection of the cyclic and radial variation of echogenicity in arterial vessels. It was found that blood echogenicity increased during systole, reaching a maximum at peak systole and then decreased to a weak level during diastole. The echogenicity profiles of blood along the vessel diameter were found to be approximately parabolic in the cardiac cycle, except for the hypoechoic zone near the center of the vessel at peak systole. The present results for human carotid arteries corroborate previous in vitro observations that showed a cyclic and radial variation of blood echogenicity, which was thought to be caused by the enhancement of erythrocyte aggregation due to the combined effects of flow acceleration and shear rate during systole.
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Affiliation(s)
- Dong-Guk Paeng
- Interdisciplinary Postgraduate Program in Biomedical Engineering, Jeju National University, Jeju, Korea
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Rouffiac V, Lavisse S, Bidault F, Paci A, Péronneau P, Roche A, Lassau N. [Validation of a new methodology for characterizing ultrasound contrast agents (UCA)]. ACTA ACUST UNITED AC 2005; 86:325-34. [PMID: 15908873 DOI: 10.1016/s0221-0363(05)81362-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE Validation of an experimental ultrasound system on erythrocyte suspensions with variable levels of aggregation and application to the echogenicity quantification of UCA under quasi-physiologic flow conditions. MATERIALS AND METHODS. The system is constituted with a Couette cell with variable applied shear rates, an ultrasound emitter/receiver and a digital scope for radio-frequency signal acquisition. Ultrasound indices (UI) were defined for the two experimental established protocols based on the gold standard laser methodology. Washed red cells with or without variable Dextran 70 kD concentrations were used to simulate a wide particle size range. A preliminary application to UCA was conducted with Levovist for calibration of the system. RESULTS For each protocol, applied ten times on identical whole blood samples, a student t-test revealed no significant variation for all UI. Results on washed red cells were in good agreement with Rayleigh's theory of ultrasound backscattering. Significant correlations were obtained between laser and UI for washed red cells with different Dextran concentrations. An elevation of 12.13 dB in backscattered intensity was obtained after addition of Levovist. CONCLUSION The constituted Couette system allowed reproducible and accurate echogenicity quantification of small scatterers such as UCA in quasi-physiologic blood flow conditions.
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Affiliation(s)
- V Rouffiac
- Laboratoire d'Imagerie du Petit Animal, Institut Gustave Roussy.
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Paeng DG, Chiao RY, Shung KK. Echogenicity variations from porcine blood I: the "bright collapsing ring" under pulsatile flow. ULTRASOUND IN MEDICINE & BIOLOGY 2004; 30:45-55. [PMID: 14962607 DOI: 10.1016/j.ultrasmedbio.2003.08.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2003] [Revised: 08/14/2003] [Accepted: 08/21/2003] [Indexed: 05/24/2023]
Abstract
The temporal and radial variations of the echogenicity from porcine blood were investigated using a linear M12L transducer with a GE LOGIQ 700 Expert system. The "bright collapsing ring" (BRCR) phenomenon, a bright echogenic ring converging from the periphery to the center of the tube wall and eventually collapsing during a pulsatile cycle in cross-sectional B-mode images, was observed from porcine blood in a mock flow loop within a 0.95-cm diameter tube under certain flow conditions. The BRCR phenomenon from porcine blood was stronger as the peak speed was increased from 10 to 25 cm/s, and the mean echogenicity and the "black hole" (BLH) phenomenon, a central echo-poor zone surrounded by a bright hyperechoic zone, became weaker. As stroke rate was increased from 20 to 60 beats/min (bpm), both the BRCR and the BLH phenomena became weaker. These two phenomena were observed at three transmitting frequencies (9, 11 and 13 MHz). As hematocrit was increased from 12 to 45%, the BRCR phenomenon became more apparent. The nonlinear behavior of backscatter as a function of hematocrit reaching a maximum at hematocrit of 10 approximately 20% was observed near the tube wall, but it changed at the center of the tube, indicating the importance of hemodynamics on the ultrasonic backscatter from flowing blood. The combined effects of shear rate and acceleration on red blood cell aggregation are suggested as a possible mechanism for these phenomena.
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Affiliation(s)
- Dong-Guk Paeng
- Faculty of Marine Industrial Engineering, Cheju National University, Jeju, South Korea.
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Rouffiac V, Guglielmi JP, Barbet A, Lassau N, Peronneau P. Application of validated ultrasound indices to investigate erythrocyte aggregation in pigs. Preliminary in vivo results. ULTRASOUND IN MEDICINE & BIOLOGY 2004; 30:35-44. [PMID: 14962606 DOI: 10.1016/j.ultrasmedbio.2003.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2003] [Revised: 09/08/2003] [Accepted: 09/16/2003] [Indexed: 05/24/2023]
Abstract
Although some studies concerning the ultrasound (US) characterization of erythrocyte aggregation reported in the literature have been conducted in vivo, none of them has led to quantitative indices. To achieve this objective, we first finalized a method on a hydrodynamic bench. Particularly, we define a kinetic protocol consisting of applying a 200 s(-1) shear rate followed up by a rapid decrease to reach a residual shear rate between 0 to 32 s(-1). From the backscattered intensity curve recorded all along the kinetic procedure, US dynamic parameters were defined and validated by correlation with reference laser indices obtained with the same model suspensions of erythrocytes (different concentrations of dextran 70 kD). A particular interesting behavior has been demonstrated when studying aggregation vs. the residual shear rate applied. The aim of the present study was to test the applicability of this aggregation kinetics protocol during in vivo investigations in pigs and possibly to recover the same aggregating behavior. The backscattered intensity was recorded all along the kinetic procedure as defined in vitro. Taking the derivative of the velocity profile recorded on 56 electronic windows, the shear rate was finely computed in the same measurement window where the backscattered intensity was calculated. Each US parameter could, therefore, be correlated with the residual shear rate corresponding to the same depth of measurement. We found that the blood aggregation behavior was identical to that observed in vitro. Apparently, a specific range of residual shear rates accelerates the activation of the aggregation process and the final aggregation level attained.
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Rouffiac V, Peronneau P, Guglielmi JP, Del-Pino M, Lassau N, Levenson J. Comparison of new ultrasound index with laser reference and viscosity indexes for erythrocyte aggregation quantification. ULTRASOUND IN MEDICINE & BIOLOGY 2003; 29:789-799. [PMID: 12837495 DOI: 10.1016/s0301-5629(03)00033-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We have previously established new ultrasonic indexes for erythrocyte aggregation using a Couette device, and validated them toward the Rayleigh's theory and reproducibility. Two hydrodynamic protocols were applied on various suspensions and their aggregation degrees were characterized by: 1. for the decreasing shear rates protocol: the power P(US) at the nominal frequency of the transducer used; 2. for the kinetic protocol: aggregation times (latency and half-rise times), variation between initial disaggregated state (Vo) and final aggregated state (V(inf)) and AI(US), which is the integral of the kinetic curve over time. The objective of the present study was to demonstrate the ability of these indexes to characterize the aggregation dynamics of suspensions with various levels of aggregation induced by concentrations of dextran 70 kD (Dx) of 10, 20 and 40 g/L added to washed red cells resuspended in saline solution. The results showed a maximum of backscattered power (P(US)) for Dx = 40 g/L with the decreasing shear rates protocol. We measured a final aggregation level (V(inf)), a minimal aggregation time (T(m)) and a maximal value of AI(US) for Dx = 40 g/L with the aggregation kinetics protocol. On the other hand, viscosity is increased with dextran concentration. These evolutions of the ultrasound (US) indexes and viscosity with dextran concentrations are consistent with literature reports. In addition, a particularly interesting phenomenon of US backscattering enhancement was observed for kinetics with no null final shear rate, which has never before been reported in such a precise manner. By another way, each of the dextran suspensions was tested on the laser erythroaggregometer that is presently considered as the "gold standard" method for erythrocyte characterization. The laser indexes (aggregation time T(a), aggregation indexes AI(10s) and AI(60s)), deduced from a kinetic protocol, have similar significance to the US ones. Statistical comparisons have been done between laser and ultrasonic indexes and significant correlations (0.001 < p < 0.01) were obtained. The set of results allowed us to conclude that ultrasonic indexes are suitable markers for the erythrocyte aggregation.
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Rouffiac V, Peronneau P, Hadengue A, Barbet A, Delouche P, Dantan P, Lassau N, Levenson J. A new ultrasound principle for characterizing erythrocyte aggregation: in vitro reproducibility and validation. Invest Radiol 2002; 37:413-20. [PMID: 12138356 DOI: 10.1097/00004424-200208000-00001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES There is no method currently available to quantify erythrocyte aggregation in vivo. In this work, using a Couette system, we defined new ultrasound indexes potentially applicable for non-invasive investigations. METHODS Two ultrasound protocols were developed: (1) a protocol in which decreasing shear rates ranging from 200 to 1 s-1 were applied to solutions; and (2) a protocol in which a 200 s-1 shear rate was initially applied followed by stoppage of flow (a kinetics protocol). New ultrasound indexes were defined as: the power PUS at the nominal frequency of each transducer, Rayleigh's slope (tangent of the curve PUS = f(log(F)) through the 3.5 to 15 MHz frequency bandwidth) and kinetic indexes characterizing the aggregation/aggregability of the suspension. RESULTS Using washed erythrocytes resuspended in saline, it was shown that the ultrasound intensity is dependent at 3.54 +/- 5.9% (NS) to the power of the frequency (theoretical value = 4). Using 10 total blood samples extracted from a single pig, good reproducibility for all indexes (5%) was demonstrated. CONCLUSIONS A suitable and reproducible methodology was developed and validated for studying erythrocyte aggregation in calibrated in vitro conditions.
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Rabhi Y, Charras-Arthapignet C, Gris JC, Ayoub J, Brun JF, Lopez FM, Janbon C, Marès P, Dauzat M. Lower limb vein enlargement and spontaneous blood flow echogenicity are normal sonographic findings during pregnancy. JOURNAL OF CLINICAL ULTRASOUND : JCU 2000; 28:407-413. [PMID: 10993968 DOI: 10.1002/1097-0096(200010)28:8<407::aid-jcu5>3.0.co;2-s] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PURPOSE We studied pregnancy-induced changes in lower limb venous function. METHODS We used plethysmography and sonography to assess the changes in venous wall distensibility, saphenous vein diameters, and spontaneous blood flow echogenicity in the common femoral veins in 190 consecutive women during and after uncomplicated pregnancies (total of 409 examinations). RESULTS The percentage of women with clinical symptoms and signs of venous insufficiency increased significantly during pregnancy. The mean diameters of the great and small saphenous veins also increased significantly, while occlusive venous plethysmography showed a decrease in parameters indicating vein distensibility. Spontaneous blood flow echogenicity in the common femoral veins was clearly visible or marked in 6% of cases during the first trimester of pregnancy, 63% during the second trimester, and 96% during the third trimester, versus 6% after delivery (p < 0.0001). The mean hematocrit decreased and the mean fibrinogen concentration increased during pregnancy. CONCLUSIONS The increase in lower limb venous pressure seen during pregnancy leads to venous overdistention and worsens blood stasis. Decreased venous flow velocity and rheological alterations result in increased red cell aggregation, giving rise to spontaneous blood flow echogenicity. Spontaneous blood flow echogenicity is therefore a normal finding during pregnancy and should not be mistaken for venous thrombosis.
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Affiliation(s)
- Y Rabhi
- Laboratory of Cardiovascular Physiology, Montpellier-Nîmes Faculty of Medicine, Avenue Kennedy, 30907 Nîmes, France
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Wu SJ, Shung KK. An in vitro study of the effects of Doppler angle, fibrinogen, and hematocrit on ultrasonic Doppler power. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1999; 46:197-204. [PMID: 18238414 DOI: 10.1109/58.741533] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
For a better understanding of the relationship between the Doppler power and erythrocyte aggregation of whole blood under steady flow in a conduit, the effects of Doppler angle, fibrinogen concentration, and hematocrit were investigated in a mock flow loop. The results show that, at a mean shear rate of 102 s(-1), there was minimal angular dependence; but at a mean shear rate of 52 s(-1), there was a weak angular dependence as the Doppler angle was varied from 40 degrees to 70 degrees . These results suggest that there was, perhaps, no or little alignment of the red cell aggregates at high shear rates. The Doppler power was found to increase nonlinearly as the fibrinogen concentration was increased; and the effect of other plasma proteins on red cell aggregation may not be negligible, although fibrinogen is the dominant factor. The results show that the variation of the Doppler power over the lumen is hematocrit dependent for hematocrits below 26%
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Affiliation(s)
- S J Wu
- CVD Corp., Irvine, CA, USA
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