Acoustic System for Diagnosis of Pneumonia and Pneumothorax using Transfer Function Analysis

使用传递函数分析诊断肺炎和气胸的声学系统

• 批准号: 10089481
• 负责人: Adam Rao
• 金额: $ 2.3万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-02-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10089481
• 关键词: Acoustic Stimulation; Acoustics; Adult; Affect; Age; Agreement; Air; Area; Atelectasis; Back; Caring; Cause of Death; Cessation of life; Chest; Child; Chronic Obstructive Airway Disease; Clinical; Clinical Research; Data Analyses; Dependence; Detection; Devices; Diagnosis; Diagnostic; Disease; Effectiveness; Exudate; Financial cost; Frequencies; Gender; Goals; Gold; Human; Imaging Phantoms; India; Infrastructure; Internist; Knee; Label; Lead; Liquid substance; Lung; Medical; Methods; Noise; Patients; Percussion; Performance; Physical Examination; Physicians; Pleural; Pneumococcal Pneumonia; Pneumonia; Pneumothorax; Population; Porifera; Pulmonary Pathology; Resources; Roentgen Rays; Sensitivity and Specificity; Severities; Side; Signal Transduction; Solid; Sternum; Stethoscopes; Stomach; Structure; Structure of parenchyma of lung; System; Techniques; Technology; Testing; Thoracic Radiography; Time; Tissues; Training; Work; base; cost; cost estimate; density; detection method; experimental study; improved; insight; lung lobe; novel; patient population; portability; prototype; response; sound; tool; transmission process

PROJECT SUMMARY/ABSTRACT Every year pneumonia is the cause of death for over a million people worldwide, with most of these deaths occurring in areas that do not have access to advanced medical infrastructure. The current clinical gold standard for detecting pneumonia is a chest x-ray, which, while effective for diagnosis, is often unavailable to patients in resource limited settings due to inhibitive financial costs. For these populations, physical examinations provide an accessible, convenient, and low-cost alternative---thus, all doctors are trained to perform the physical exam. The physical exam technique of percussion is performed by tapping specific areas of the back and assessing whether the resulting sound corresponds to healthy or diseased tissue. Unfortunately, differences in physician technique lead to inconsistent findings and dismissal of the percussion method when x-ray machines are available. The goal of our device is to quantify these findings to eliminate interobserver error and harness the diagnostic power of percussion to provide a low-cost, quantitative physical examination tool for the diagnosis of pneumonia in patient populations with limited access to chest radiography. We have developed a prototype device that provides acoustic stimulation to the chest; sound is recorded from the back using an electronic stethoscope and this recording is used to estimate the chest cavity's acoustic transfer function. The transfer function characterizes the strength of response of a system to different frequencies and can be used to distinguish between different systems. Our specific aims focus on developing a method to study the effects on the acoustic transfer function due to structural changes in the lungs during pneumonia (Aim 1) and to explore the generalizability of this approach to pneumothorax specifically as well as other lung pathologies (Aim 2). In Aim 1, we hypothesize that the accumulation of exudate (fluid) in a lobe of the lungs in pneumonia will lead to better sound transmission of higher frequencies compared to healthy lung. First, we will use a sponge with similar density to human lung tissue as an imaging phantom to improve our device's signal-to-noise ratio and streamline data analysis. Second, we will perform our experiments in patients comparing the healthy side of their lungs to the side with lobar pneumonia. Finally, we will develop a classifier that can take additional variables such as age and gender into consideration to improve performance of our test and return a severity score of pneumonia based on acoustic findings. For Aim 2, our hypothesis is that the accumulation of air in pleural spaces will reduce transmission of sound, especially at higher frequencies. We will first perform an experiment with an air-filled cavity (stomach) compared to solid tissue (knee) to determine the effect of air accumulation on the transfer function. Next, as in Aim 1, we will perform tests on patients comparing the side with the pneumothorax to the healthy side. Finally, we will develop a classifier to provide a severity score of pneumothorax. We anticipate that the findings from our studies will provide novel insight into the feasibility of acoustic diagnosis of pneumonia and pneumothorax.

项目概要/摘要 每年肺炎是全世界超过一百万人的死亡原因，其中大部分死亡 发生在无法获得先进医疗基础设施的地区。目前临床黄金 检测肺炎的标准是胸部 X 光检查，虽然对诊断有效，但通常无法用于诊断 由于经济成本抑制而处于资源有限环境中的患者。对于这些人群来说，身体 检查提供了一种容易获得、方便且低成本的替代方案——因此，所有医生都接受过培训 进行体检。敲击的体检技术是通过敲击特定区域来进行的 背部并评估产生的声音是否对应于健康或患病的组织。 不幸的是，医生技术的差异导致结果不一致并放弃敲击 当 X 射线机可用时的方法。我们设备的目标是量化这些发现，以消除 观察者间的误差并利用打击乐的诊断能力提供低成本、定量的物理 用于诊断胸部接触受限的患者群体的肺炎的检查工具 射线照相。我们开发了一种原型设备，可以为胸部提供声音刺激；声音是 使用电子听诊器从背部记录，该记录用于估计胸部 腔体的声学传递函数。传递函数表征系统响应的强度 不同的频率可以用来区分不同的系统。我们的具体目标集中于 开发一种方法来研究由于结构变化对声学传递函数的影响 肺炎期间的肺部（目标 1）并探索这种方法对气胸的普遍适用性 特别是以及其他肺部病变（目标 2）。在目标 1 中，我们假设 肺炎肺叶中的渗出物（液体）将导致更高频率的声音更好地传输 与健康的肺相比。首先，我们将使用与人体肺组织密度相似的海绵作为成像 phantom 可以提高我们设备的信噪比并简化数据分析。其次，我们将执行 我们对患者进行的实验将健康侧的肺部与患有大叶性肺炎的一侧进行了比较。最后， 我们将开发一个分类器，可以考虑年龄和性别等其他变量 提高我们的测试性能，并根据声学结果返回肺炎的严重程度评分。为了目标 2、我们的假设是胸膜腔内空气的积聚会减少声音的传播，尤其是 在更高的频率下。我们首先将进行一个实验，将充气腔（胃）与固体进行比较 组织（膝盖）以确定空气积聚对传递函数的影响。接下来，如目标 1 所示，我们将 对患者进行测试，将气胸一侧与健康一侧进行比较。最后，我们将 开发一个分类器来提供气胸的严重程度评分。我们预计我们的调查结果 研究将为肺炎和气胸的声学诊断的可行性提供新的见解。