Improved ultrasound imaging using elevated acoustic output

使用提高的声输出改进超声成像

• 批准号: 9223699
• 负责人: Kathryn Radabaugh Nightingale
• 金额: $ 45.27万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9223699
• 关键词: Abdomen; Acoustics; Acute; American; Body Image; Clinical; Custom; Data; Detection; Development; Diagnosis; Diagnostic; Diagnostic Imaging; Failure; Frequencies; Gases; Generations; Geometry; Goals; Guidelines; Hepatic Mass; Image; Imagery; In Situ; Institutes; Lead; Lesion; Link; Malignant - descriptor; Manufacturer Name; Measurement; Mechanics; Medicine; Methods; Modality; Noise; Obesity; Output; Overweight; Pain; Patient Schedules; Patients; Penetration; Performance; Physiologic pulse; Power Sources; Primary carcinoma of the liver cells; Property; Pulse Pressure; Reporting; Research; Research Design; Resolution; Risk; Shapes; Signal Transduction; Source; Structure; System; Time; Tissues; Transducers; Ultrasonics; Ultrasonography; United States; Water; Work; abdominal wall; attenuation; base; design; disease diagnosis; imaging modality; imaging study; imaging system; improved; in vivo; indexing; patient population; pressure; prototype; public health relevance; screening; second harmonic; simulation; success; tool

 DESCRIPTION (provided by applicant): Ultrasonic imaging is among the most widely used abdominal imaging modalities in the United States. However, ultrasonic image quality is reported to be insufficient for diagnosis in up to 40% of patients, a challenge often correlated with obesity. The major problems are lack of penetration and reverberation clutter. We hypothesize that increasing the Mechanical Index (MI) from the current limit of 1.9 to values in the 2.4-3.4 range, with concomitant transmit pulse pressure increases from 40 to 200%, will markedly improve B-mode, har- monic, and Doppler image quality. We have designed this proposal to focus on harmonic imaging. Tissue harmonic imaging (THI) is a nonlinear method that is more robust to reverberation clutter and off-axis scattering than fundamental imaging, and has found great success in improving ultrasonic image quality. However, har- monic signal levels are 15-20 dB lower than fundamental signals, which leads to challenges with signal-to-noise ratio and depth penetration in difficult-to-image patients. The in situ pressures used in diagnostic ultrasound imaging have been subject to a de facto upper limit established by the United States FDA guidelines for the Mechanical Index (MI<1.9), a value which is based upon historic values, rather than being linked to scientific evidence of bioeffects. In tissues without gas bodies, cavitation based bioeffects have only been reported at diagnostic frequencies and pulse durations using MI values greater than 5.0. The American Institute of Ul- trasound in Medicine (AIUM) recently concluded that exceeding the recommended maximum MI given in the FDA guidance up to an estimated in situ value of 4.0, could be warranted without concern for increased risk of cavitation in non-fetal tissues without gas bodies, if imaging in this heretofore unexplored output regime were associated with a corresponding significant clinical benefit. We have obtained preliminary in vivo data using elevated MI harmonic imaging demonstrating +20 dB increases in harmonic signal level, penetration depth increases of up to 40%, and structural contrast-to-noise ratio increases from 12-500%, enabling visualization of additional structures. The primary goals of this work are to optimize elevated MI harmonic image quality and to quantify the resulting image quality improvements. There are 3 specific aims: 1) To extend our 3D nonlinear simulation tools to perform a parametric analysis of varying tissue properties and transducer configurations to optimize harmonic signal generation and image quality in elevated MI pulse inversion har- monic imaging, and to determine the relationship between water-based estimates and in situ measurements in the elevated MI output regime. 2) To design and implement a real-time prototype elevated MI system using commercial curvilinear abdominal arrays and a custom designed prototype large aperture low frequency diag- nostic array on a commercial grade scanner. 3) To quantify improvements in imaging performance afforded by the use of elevated MIs in patients scheduled for ultrasonic abdominal imaging studies, and in patients known to have malignant liver masses.

 描述（由适用提供）：超声成像是美国使用最广泛的腹部成像方式之一。但是，据报道，超声图像质量对多达40％的患者的诊断不足，这一挑战通常与肥胖有关。主要问题是缺乏渗透和恢复混乱。我们假设将机械指数（MI）从当前限制的1.9增加到2.4-3.4范围内的值，而随之而来的发射压力从40％增加到200％，将显着改善B模式，Har-Monic和Doppler图像质量。我们设计了此建议以专注于谐波成像。组织谐波成像（THI）是一种非线性方法，比基本成像更适合恢复混乱和轴向散射，并且在改善超声图像质量方面取得了巨大成功。然而，竖音信号水平比基本信号低15-20 dB，这导致了难度和深度患者的信噪比和深度渗透的挑战。诊断超声成像中使用的原位压力已受到美国FDA机械指数指南（MI <1.9）确立的事实上的上限，该值基于历史值，而不是与生物效应的科学证据相关联。在没有的组织中 气体，基于空化的生物效应仅在诊断频率和脉冲持续时间进行了使用大于5.0的脉冲持续时间。美国UL-TRASOUND的医学研究所（AIUM）最近得出结论，超过FDA指南中建议的最大MI，直到估计的原位价值为4.0，而不必担心在没有气体的无气体体内的空气风险的情况下，如果在这个无源的未探索的未探索的产出方案中，则可以将相应的临床与相应的相关性相关联。我们使用升高的MI谐波成像获得了+20 dB的谐波信号水平，渗透深度增加高达40％，结构性对比度与噪声比率从12-500％增加，从而使其他结构的可视化增加，并且结构上的对比度与噪声比率增加。这项工作的主要目标是优化升高的MI谐波图像质量并量化所得图像质量的改进。有3个特殊目标：1）扩展我们的3D非线性仿真工具，以对各种组织性能和换能器配置进行参数分析，以优化高架MI脉冲反转形式成像中的谐波信号产生和图像质量，并确定水性估计和现场测量的高度MI Infuptime MI Impime Inmim Inmime Inmim inter基于水的估计。 2）使用商业曲面腹部阵列和定制设计的原型大量光圈低频诊断阵列在商业级扫描仪上设计和实现实时原型高架MI系统。 3）用计划进行超声腹部成像研究的患者以及已知患有恶性肝脏肿块的患者的使用中使用MIS的升高来量化成像性能的改善。