No abstract available.
Lung* ; Microbubbles*

No abstract available.
Humans ; Infant, Newborn* ; Microbubbles*

No abstract available.
Genetic Therapy* ; Microbubbles* ; Ultrasonography*

Contrast echocardiography is an important technique that .,/ can be used to examine the cardiac cavity, vascular tructure, intracardiac shunt, and myocardial microcirculation. uses gasfilled microbubbles and various imaging techiques. The properties of microbubbles and their interaction Ath ultrasound are important in ultrasoundenhanced conast imaging. This article will describe microbubbie physics id new ultrasound techniques that are necessary to under--and the basics of contrast echocardiography. The utility of )ntrast echocardiography in various clinical scenarios will be so described.
Echocardiography* ; Microbubbles ; Microcirculation ; Myocardium ; Ultrasonography

No abstract available.
Microbubbles* ; Respiratory Distress Syndrome, Newborn*

Correlation between nonlinear subharmonic scattering of ultrasound contrast agent microbubbles and ambient pressure is expected to be used for local brain tissue pressure monitoring. Although high-frequency ultrasound has achieved high-resolution imaging of intracranial microvessels, the research on high-frequency subharmonic scattering characteristics of microbubbles is insufficient at present, which restricts the research progress of estimating local brain tissue pressure based on high-frequency subharmonic scattering of microbubbles. Therefore, under the excitation of 10 MHz high-frequency ultrasound, the effects of different acoustic pressures and ambient pressures on the high-frequency subharmonic scattering characteristics of three different ultrasound contrast agents including SonoVue, Sonazoid and Huashengxian were investigated in this in vitro study. Results showed that the subharmonic scattering amplitudes of the three microbubbles increased with the increase of ambient pressure at the peak negative acoustic pressures of 696, 766 and 817 kPa, and there was a favorable linear correlation between subharmonic amplitude and ambient pressure. Under the above three acoustic pressures, the highest correlation coefficient of SonoVue was 0.948 ( P = 0.03), the highest sensitivity of pressure measurement was 0.248 dB/mm Hg and the minimum root mean square error (RMSE) was 2.64 mm Hg. Sonazoid's highest correlation coefficient was 0.982 ( P < 0.01), the highest sensitivity of pressure measurement was 0.052 dB/mm Hg and the minimum RMSE was 1.51 mm Hg. The highest correlation coefficient of Huashengxian was 0.969 ( P = 0.02), the highest sensitivity of pressure measurement was 0.098 dB/mm Hg and the minimum RMSE was 2.00 mm Hg. The above in vitro experimental results indicate that by selecting ultrasound contrast agent microbubbles and optimizing acoustic pressure, the correlation between high-frequency subharmonic scattering of microbubbles and ambient pressure can be improved, the sensitivity of pressure measurement can be upgraded, and the measurement error can be reduced to meet the clinical demand for local brain tissue pressure measurement, which provided an important experimental basis for subsequent research in vivo.
Contrast Media ; Microbubbles ; Ultrasonography/methods*

With focused ultrasound (FUS) and microbubbles, BBB can be transiently disrupted with a localized and non-invasive approach. BBB disruption induced by FUS has made progressions to move forward on delivery of therapeutic agents into a brain in a specific area of brain for better treatment of neurological diseases. In addition to be used as an improvement of drug delivery, BBB disruption has been found to induce biological effects such as a clearance of protein aggregation which cause Alzheimer's disease, regulation of proteins which facilitate drug uptake, and modulation of neuronal function and neurogenesis. In this review, we discuss overview about the principles of BBB opening with FUS and milestones in these biological effects of FUS-induced BBB disruption.
Alzheimer Disease ; Brain ; Microbubbles ; Neurogenesis ; Neurons ; Ultrasonography*

Recent advancements in ultrasound and microbubble (USMB) mediated drug delivery technology has shown that this approach can improve spatially confined delivery of drugs and genes to target tissues while reducing systemic dose and toxicity. The mechanism behind enhanced delivery of therapeutics is sonoporation, the formation of openings in the vasculature, induced by ultrasound-triggered oscillations and destruction of microbubbles. In this review, progress and challenges of USMB mediated drug delivery are summarized, with special focus on cancer therapy.
Drug Delivery Systems ; Genetic Therapy ; Microbubbles ; Ultrasonography

Contrast-enhanced ultrasonography (CEUS) using microbubble ultrasonography contrast agent can show the vascular structure and unique contrast enhancement patterns of focal liver lesions, including hepatocellular carcinoma (HCC). CEUS shows three phases, similar to a vascular pattern on computer tomography (CT), and typical arterial enhancement and portal or late phase washout in HCC. CEUS can show real-time images without nephrotoxicity or radiation hazard and can be used as guidance for loco-regional treatment and estimation of treatment response of HCC. In addition, some data recently revealed the usefulness of CEUS in the early estimation of response to anti-cancer pharmacological (i.e., sorafenib) therapy in advanced HCC. Although CEUS has limitations in clinical practice and more investigation is needed for its validation, it is recommended as a main diagnostic modality in a few major clinical practice guidelines for HCC. Thus, greater understanding of CEUS is necessary to extend its application in real practice for diagnosis and management of diseases.
Carcinoma, Hepatocellular ; Diagnosis ; Liver ; Microbubbles ; Ultrasonography

PURPOSE: To compare the results of harmonic ultrasound (US) renal perfusion imaging using 99mTc-DTPA as contrast agent with those obtained when a microbubble contrast medium was used. MATERIALS AND METHODS: Twenty rabbits underwent harmonic US renal perfusion imaging using 99mTc-DTPA as contrast agent, and the imaging procedure was then repeated using a microbubble contrast medium. Three different concentrations of contrast media (200, 300 and 400 mg/ml) and two different scanning techniques (intermittent and continuous) were used, and the images obtained were assessed using six different methods. By means of a computer program, the images were converted to a renal perfusion curve and Tpeak values were calculated. Images obtained after use of the two different contrast media were compared. RESULTS: Tpeak at renal perfusion imaging using 99mTc-DTPA was 6.3+/-0.9 sec, and where microbubble contrast agent was used, the findings were was as follows: 13.8+/-1.6 sec (method 1), 6.5+/-1.1 sec (method 2), 14.8+/-1.7 sec (method 3), 6.6+/-1.0 sec (method 4), 15.2+/-2.0 sec (method 5), 6.4+/-0.7 sec (method 6). Method 6 had the highest correlation coefficients. CONCLUSION: In conclusion, the harmonic ultrasound renal perfusion images acquired using 99mTc-DTPA were similar to those obtained using microbubble contrast agent. Continuous scanning techniques showed correlation.
Contrast Media ; Microbubbles ; Perfusion Imaging ; Perfusion* ; Rabbits ; Ultrasonography*