On the Relationship between Dynamic Contrast-Enhanced Ultrasound Parameters and the Underlying Vascular Architecture Extracted from Acoustic Angiography

Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA.     

Effect of body position on qualitative and quantitative ultrasound assessment of gastric fluid contents

We assessed the impact of raising the upper section of the bed, and patient positioning, on ultrasound assessment of gastric fluid contents. We performed ultrasound examinations in 25 subjects lying on their back, left and right sides at bed angles of 0°, 30°, 45° and 90°; this was carried out while the subjects were fasted, and repeated 10 min after drinking ≥ 50 ml water. After drinking, gastric contents were detected more frequently in the 45° semirecumbent position compared with the supine and 30° positions. The diagnostic performance of the Perlas qualitative grading scale to detect gastric fluid volume > 1.5 ml.kg⁻¹ was improved at 45°, compared with 0° and 30° angles. The use of a composite ultrasound grading scale at a 45° angle was associated with the best performance, with a sensitivity and specificity of 82%. Antral cross-sectional area was significantly increased when measured in the right lateral position, but there was no effect of raising the bed. In conclusion, raising the upper section of the bed significantly affected qualitative assessment of gastric fluid contents. Further studies are required to determine the most appropriate composite ultrasound grading scale and bed angle for fast and reliable qualitative ultrasound detection of fluid volumes > 1.5 ml.kg⁻¹.     

Sonothrombolysis in ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

BackgroundPreclinical studies have demonstrated that high mechanical index (MI) impulses from a diagnostic ultrasound transducer during an intravenous microbubble infusion (sonothrombolysis) can restore epicardial and microvascular flow in acute ST-segment elevation myocardial infarction (STEMI).ObjectivesThis study tested the clinical effectiveness of sonothrombolysis in patients with STEMI.MethodsPatients with their first STEMI were prospectively randomized to either diagnostic ultrasound–guided high MI impulses during an intravenous Definity (Lantheus Medical Imaging, North Billerica, Massachusetts) infusion before, and following, emergent percutaneous coronary intervention (PCI), or to a control group that received PCI only (n = 50 in each group). A reference first STEMI group (n = 203) who arrived outside the randomization window was also analyzed. Angiographic recanalization before PCI, ST-segment resolution, infarct size by magnetic resonance imaging, and systolic function (LVEF) at 6 months were compared.ResultsST-segment resolution occurred in 16 (32%) high MI PCI versus 2 (4%) PCI-only patients before PCI, and angiographic recanalization was 48% in high MI/PCI versus 20% in PCI only and 21% in the reference group (p < 0.001). Infarct size was reduced (29 ± 22 g high MI/PCI vs. 40 ± 20 g PCI only; p = 0.026). LVEF was not different between groups before treatment (44 ± 11% vs. 43 ± 10%), but increased immediately after PCI in the high MI/PCI group (p = 0.03), and remained higher at 6 months (p = 0.015). Need for implantable defibrillator (LVEF ≤30%) was reduced in the high MI/PCI group (5% vs. 18% PCI only; p = 0.045).ConclusionsSonothrombolysis added to PCI improves recanalization rates and reduces infarct size, resulting in sustained improvements in systolic function after STEMI. (Therapeutic Use of Ultrasound in Acute Coronary Artery Disease; NCT02410330).     

彩色多普勒超声在诊断致密型乳腺癌患者术后对侧乳腺癌中的价值

目的:探讨彩色多普勒超声检查在提高致密型乳腺癌患者术后对侧乳腺癌(contralateral breast cancer,CBC)检出率中的应用价值。方法:对我院乳腺癌患者行术后常规乳腺超声及钼靶检查，229名患者考虑对侧乳腺病变，根据腺体含量对其进行分型，并应用BI-RADS分级对病变进行评估。结果:超声诊断CBC的特异性、准确率与阳性预测值均明显好于钼靶检查，致密型乳腺钼靶CBC检出率明显下降，超声检查CBC检出率明显增高，BI-RADS 4A与4B分级中脂肪型及少量腺体型乳腺钼靶CBC的检出率明显高于超声检查，BI-RADS 4C与5分级中，乳腺分型对超声及钼靶筛查CBC的结果影响不大。结论:超声及钼靶的联合检查在CBC的检出中发挥重要作用，而乳腺分型与BI-RADS分类诊断对乳腺肿瘤的临床诊断效能和应用价值意义重大。