Nakano, H. I. D. E. H. I. K. O.Hashimoto, H. I. D. E. K. I.Mochizuki, M. A. S. A. K., INaraba, H. I. R. O. M. U....
10页
查看更多>>摘要：A non-invasive method for assessment of intravascular volume for optimal fluid administration is needed. We here conducted a preliminary study to confirm whether cardiac variation in the internal jugular vein (IJV), evaluated by ultrasound, predicts fluid responsiveness in patients in the emergency department. Patients who presented to the emergency department between August 2019 and March 2020 and required infusions were enrolled. We recorded a short-axis video of the IJV, respiratory variability in the inferior vena cava and stroke volume variations using the ClearSight System (Edwards Lifesciences, Irvine, CA, USA) before infusion of 500 mL of crystalloid fluid. Cardiac variations in the cross-sectional area of the IJV were measured by speckle tracking. Among the 148 patients enrolled, 105 were included in the final analysis. Fluid responsiveness did not correlate with the cardiac collapse index (13.6% vs. 16.8%, p = 0.24), but correlated with stroke volume variations (12.5% vs. 15.6%, p = 0.026). Although it is a simple correction, the cardiac collapse index correlated with stroke volume corrected by age (r = 0.25, p = 0.01), body surface area (r = 0.33, p = 0.002) and both (r = 0.35, p = 0.001). Cardiac variations in the IJV did not predict fluid responsiveness in the emergency department, but may reflect stroke volume. (E-mail: be.rann1988jp@gmail.com) (C) 2022 The Author(s). Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine & Biology.
MARANTA, F. R. A. N. C. E. S. C. O.CIANFANELLI, L. O. R. E. N. Z. O.PISTONI, A. N. N. A.AVITABILE, M. A. R. I. A....
11页
查看更多>>摘要：Diaphragm dysfunction is common after cardiac surgery and can be evaluated with ultrasonography (US). We aimed at assessing with US the incidence of diaphragmatic dysfunction and the impact of cardiovascular rehabilitation (CR) on its recovery. A single-center cohort study was performed. Patients were enrolled after cardiac surgery. The 6-min walking test (6MWT) and diaphragm US were performed at CR admission and after 10 rehabilitative sessions. One hundred eighty-five patients were eligible for final analysis. One hundred thirtyone patients (70.8%) were found to have diaphragm dysfunction (excursion <2 cm). After CR, 68 patients regained normal diaphragmatic function; those with persistent dysfunction had a lower level of functional performance on the 6MWT (metabolic equivalents of tasks: 3.3 vs. 3.6, p = 0.013). The patients who underwent combined surgery (adjusted odds ratio [aOR] = 4.09, p = 0.001) and those with post-operative pneumothorax (aOR = 3.02, p = 0.042) were at increased risk of failure to improve diaphragmatic excursion. US parameters were more powerful tools in predicting diaphragmatic evolution compared with the 6MWT indexes: baseline diaphragm excursion and thickening fraction were associated with complete diaphragmatic functional recovery after CR (aOR = 9.101, p < 0.001, and aOR =1.058, p = 0.020 respectively). US is a valuable tool for the assessment of post-operative diaphragmatic dysfunction and can identify patients at risk of diaphragmatic recovery failure. (E-mail: maranta.francesco@hsr.it) (c) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved. tional recovery.
Chen, Y. A. N. L. I. N. G.Lu, Q. I. N. G.Zhu, Y. U. L., IHuang, B. E. I. J. I. A. N....
12页
查看更多>>摘要：The goal of the study described here was to define the predictive value of pre-operative clinical information and contrast-enhanced ultrasound (CEUS) imaging characteristics in combined hepatocellular-cholangiocarcinoma (CHC) patients with microvascular invasion (MVI). Seventy-six patients with pathologically confirmed CHC were enrolled in this study, comprising 18 patients with MVI-positive status and 58 with MVInegative CHC nodules. The pre-operative clinical data and CEUS imaging features were retrospectively analyzed. Univariate and multivariate analyses were performed to identify the potential predictors of MVI in CHC. Recurrence-free survival (RFS) after hepatectomy was compared between patients with different MVI status using the log-rank test and Kaplan-Meier survival curves. Univariate analysis indicated that the following parameters of patients with CHC significantly differed between the MVI-positive and MVI-negative groups (p < 0.05): tumor size, a-fetoprotein > 400 ng/mL, enhancement patterns in arterial phase and marked washout during the portal venous phase on CEUS. On multivariate logistic regression analysis, only the CEUS characteristics of heterogeneous enhancement (odds ratio = 6.807; 95% confidence interval [CI]: 1.099, 42.147; p = 0.039) and marked washout (odds ratio = 4.380; 95% CI: 1.050,18.270; p = 0.043) were identified as independent predictors of MVI in CHC. The combination of the two risk factors in predicting MVI achieved a better diagnostic performance than each parameter alone, with an area under the receiver operating characteristic curve of 0.736 (0.622, 0.830). After hepatectomy, CHC patients with MVI exhibited earlier recurrence compared with those without MVI (hazard ratio =1.859; 95% CI: 0.8699-3.9722, p = 0.046). The CEUS imaging features of heterogeneous enhancement in the arterial phase and marked washout during the portal venous phase were the potential predictors of MVI in CHC. Aside from that, CHC patients with MVI had an earlier recurrence rate than those without MVI after surgery. (C) 2022 Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine & Biology.
Jimenez, Abelino vargasCabezas, Diana carolina ochoaDelay, M. I. C. H. A. E. L.Gomez, Itziar Gonzalez...
13页
查看更多>>摘要：The analysis of cell motion in an acoustic field is of interest as it can lead to new methods of cell separation, isolation and manipulation for diagnosis and treatment of diseases. Studies of the motion of different species of Leishmania parasites during exposure to ultrasonic standing waves in a microfluidic device allowed identification of acoustic responses of these parasites in their promastigote and amastigote forms. Both forms exhibited a positive acoustic contrast factor and were driven toward the pressure node established in the center of the channel by the acoustically induced radiation force (FR). Promastigotes experience calculated FR amplitudes one order of magnitude larger than those experienced by amastigotes because of the measured differences in volume. The aggregates formed at the pressure node have distinct shapes and stability conditions, for both promastigotes and amastigotes. (C) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved.
Cao, E. L. O. D. I. E.Greillier, P. A. U. L.Loyet, R. A. P. H. A. E. L.Chavrier, F. R. A. N. C. O. I. S. E....
14页
查看更多>>摘要：High-intensity focused ultrasound (HIFU) is a promising method used to treat cardiac arrhythmias, as it can induce lesions at a distance throughout myocardium thickness. Numerical modeling is commonly used for ultrasound probe development and optimization of HIFU treatment strategies. This study was aimed at describing a numerical method to simulate HIFU thermal ablation in elastic and mobile heart models. The ultrasound pressure field is computed on a 3-D orthonormal grid using the Rayleigh integral method, and the attenuation is calculated step by step between cells. The temperature distribution is obtained by resolution of the bioheat transfer equation on a 3-D non-orthogonally structured curvilinear grid using the finite-volume method. The simulation method is applied on two regions of the heart (atrioventricular node and ventricular apex) to compare the thermal effects of HIFU ablation depending on deformation, motion type and amplitude. The atrioventricular node requires longer sonication than the ventricular apex to reach the same lesion volume. Motion considerably influences treatment duration, lesion shape and distribution in cardiac HIFU treatment. These results emphasize the importance of considering local motion and deformation in numerical studies to define efficient and accurate treatment strategies. (E-mail: elodie.cao@inserm.fr) (C) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved.
Glickstein, B. A. R.Levron, M. I. K. A.Shitrit, S. A. R. A. H.Aronovich, R. A. M. O. N. A....
11页
查看更多>>摘要：Mechanical ultrasound surgery methods use short, high-intensity pulses to fractionate tissues. This study reports the development of a two-step technology for low-energy mechanical ultrasound surgery of tissues using nanodroplets to reduce the pressure threshold. Step 1 consists of vaporizing the nanodroplets into gaseous microbubbles via megahertz ultrasound excitation. Then, low-frequency ultrasound is applied to the microbubbles, which turns them into therapeutic warheads that trigger potent mechanical effects in the surrounding tissue. The use of nanoscale nanodroplets coupled with low-frequency ultrasound reduces the pressure threshold required for mechanical ultrasound surgery by an order of magnitude. In addition, their average diameter of 300 nm can overcome challenges associated with the size of microbubbles. Optimization experiments were performed to determine the ultrasound parameters for nanodroplet vaporization and the subsequent microbubble implosion processes. Optimal vaporization was obtained when transmitting a 2-cycle excitation pulse at a center frequency of 5 MHz and a peak negative pressure of 4.1 MPa (mechanical index = 1.8). Low-frequency insonation of the generated microbubbles at a center frequency of 850, 250 or 80 kHz caused enhanced contrast reduction at a center frequency of 80 kHz, compared with the other frequencies, while operating at the same mechanical index of 0.9. Nanodroplet-mediated insonation of ex vivo chicken liver samples generated mechanical damage. Low -frequency treatment at a mechanical index of 0.9 and a center frequency of 80 kHz induced the largest lesion area (average of 0.59 mm2) compared with 250-and 850-kHz treatments with the same mechanical index (average lesions areas of 0.29 and 0.19 mm2, respectively, p < 0.001). The two-step approach makes it possible to conduct both the vaporization and implosion stages at mechanical indices below 1.9, thus avoiding undesired mechanical damage. The findings indicate that coupled with low-frequency ultrasound, nanodroplets can be used for low energy mechanical ultrasound surgery. (C) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved.
Nitta, N. A. O. T. A. K. A.Ishiguro, Y. A. S. U. N. A. O.Sasanuma, H. I. D. E. K. I.Takayama, N. O. R. I. Y. A....
16页
查看更多>>摘要：Acoustic radiation force impulse (ARFI) imaging and shear wave elastography use a "push pulse. " The push pulse, which is referenced as an ARFI in this study, has a longer duration than that of conventional diagnostic pulses (several microseconds). Therefore, there are concerns regarding thermal safety in vivo. However, few in vivo studies have been conducted using living animals. In this study, to suggest a concept for deciding an ARFI output and cooling time while considering thermal safety, the liver (with and without an ultrasound contrast agent) and femur bone surface of living rabbits were exposed to an ARFI, and the maximum temperature rise, temperature rise for 5-min duration, and cooling time were measured via a thermocouple. While testing within the regulation limits of diagnostic ultrasound outputs, a maximum temperature rise on the femur bone surface exceeded the allowable temperature rise (1.5C) in the British Medical Ultrasound Society (BMUS) statement. However, using the linear relationships between the pulse intensity integral (PII) of a single pulse and the above three temperature parameters, PII may be determined so that the maximum temperature rise is within the allowable temperature rise in the BMUS statement. The cooling time can be estimated from the PII. (E-mail: n.nitta@aist.go.jp) (C) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved.
Leth-olsen, MartinDohlen, GauteTorp, HansNyrnes, Siri Ann...
12页
查看更多>>摘要：There is a risk of gaseous and solid micro-embolus formation during transcatheter cardiac interventions and surgery in children with congenital heart disease (CHD). Our aim was to study the burden of high intensity transient signals (HITS) during these procedures in infants. We used a novel color M-mode Doppler (CMD) technique by NeoDoppler, a non-invasive ultrasound system based on plane wave transmissions for transfontanellar continuous monitoring of cerebral blood flow in infants. The system displays CMD with 24 sample volumes and a Doppler spectrogram. Infants with CHD undergoing transcatheter interventions (n = 15) and surgery (n = 13) were included. HITS were manually detected based on an "embolic signature " in the CMD with corresponding intensity increase in the Doppler spectrogram. Embolus-to-blood ratio (EBR) defined HITS size. A total of 1169 HITS with a median EBR of 9.74 dB (interquartile range [IQR]: 5.10-15.80 dB) were detected. The median number of HITS in the surgery group was 45 (IQR: 11-150), while in the transcatheter group the median number was 12 (IQR: 7-24). During cardiac surgery, the highest number of HITS per hour was seen from initiation of cardiopulmonary bypass to aortic X-clamp. In this study we detected frequent HITS and determined the feasibility of using NeoDoppler monitoring for HITS detection. (C) 2022 The Author(s). Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine & Biology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Lo, S. H. U. N. YuLee, Jetty C. Y.Wan, M. F.Yu, Alfred c. h....
14页
查看更多>>摘要：(Received 30 April 2021; revised 23 February 2022; in final form 24 February 2022) Abstract-Microbubble-mediated ultrasound (MB-US) can be used to realize sonoporation and, in turn, facilitate the transfection of leukocytes in the immune system. Nevertheless, the bio-effects that can be induced by MB-US exposure on leukocytes have not been adequately studied, particularly for different leukocyte lineage subsets with distinct cytological characteristics. Here, we describe how that same set of MB-US exposure conditions would induce heterogeneous bio-effects on the three main leukocyte subsets: lymphocytes, monocytes and granulocytes. MB-US exposure was delivered by applying 1-MHz pulsed ultrasound (0.50-MPa peak negative pressure, 10% duty cycle, 30-s exposure period) in the presence of microbubbles (1:1 cell-to-bubble ratio); sonoporated and non-viable leukocytes were respectively labeled using calcein and propidium iodide. Flow cytometry was then performed to classify leukocytes into their corresponding subsets and to analyze each subset's postexposure viability, sonoporation rate, uptake characteristics and morphology. Results revealed that, when subjected to MB-US exposure, granulocytes experienced the highest loss of viability (64.0 +/- 11.0%) and the lowest sonoporation rate (6.3 +/- 2.5%), despite maintaining their size and granularity. In contrast, lymphocytes exhibited the lowest loss of viability (20.9 +/- 7.0%), while monocytes had the highest sonoporation rate (24.1 +/- 13.6%). For these two sonoporated leukocyte subsets, their cell size and granularity were found to be reduced. Also, they exhibited graded levels of calcein uptake, whereas sonoporated granulocytes achieved only mild calcein uptake. These heterogeneous bio-effects should be accounted for when using MB-US and sonoporation in immunomodulation applications. (E-mail: alfred.yu@uwaterloo.ca) (c) 2022 The Author(s). Published by Elsevier Inc. on behalf of World Federation for Ultrasound in Medicine & Biology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Iwashita, H. I. D. E. Y. U. K. I.Shakado, S. A. T. O. S. H., IYoshimaru, N. A. M. I. K. O.Tanaka, H. I. T. O. M. I....
8页
查看更多>>摘要：This retrospective study was aimed (i) at elucidating the correlation between fatty liver diagnoses based on the plain computed tomography (CT) value and those based on the attenuation coefficient (AC) value determined with the ultrasound-guided attenuation parameter (UGAP) and (ii) at evaluating the diagnostic power of AC values. We included 125 patients who underwent blood tests, abdominal ultrasonography and abdominal CT at our department between April 2020 and March 2021. Hepatic fat infiltration was categorized as S0 (< 5%), S1 (>= 5 and 30 <%), S2 (>= 30 and < 50%) or S3 (>= 50%). The diagnostic ability of UGAP-determined AC was evaluated using receiver operating characteristic (ROC) curve analysis, and the correlation between AC value and fatty liver grade by CT value. The coefficient of correlation (r) between the AC value and plain CT value was -0.6188, indicating a moderate relationship. For diagnosing grade >= S1 (n = 44), the area under the ROC curve (AUROC) was 0.8541, sensitivity 84.1%, specificity 81.5% and cutoff value 0.676 dB/cm/MHz. In diagnosing grade >= S2 (n = 35), the AUROC was 0.8603, sensitivity 88.6%, specificity 81.1% and cutoff value 0.694 dB/cm/MHz. In diagnosing grade = S3 (n = 18), the AUROC was 0.9016, sensitivity 94.5%, specificity 81.9% and cutoff value, 0.704 dB/cm/MHz. The AC value is useful in diagnosing fatty liver. (C) 2022 World Federation for Ultrasound in Medicine & Biology. All rights reserved.
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