Spectroscopic data of pleural effusion

Pleural effusion is a medical condition having its etiology in various primary diseases, eg. cardiological, pulmonological, and oncological. It is a side effect of diseases such as pneumonia, tuberculosis, cancer, heart failure, and inflammation which are responsible for causing inflammatory diseases of the pleura. Late detection of pleural effusion disturbs the respiratory function, heart operation or may cause bleeding into the pleural cavity. In such a case, there is an immediate requirement for medical intervention and drainage of the pleural space or execution of pleurodesis causing pleural plaques to fuse, which is an invasive and potentially life-threatening procedure.
Therefore, patients with fluid in the pleural cavity, especially a group with recurrent pleural effusion should be continuously monitored.
In a standard clinical procedure, the presence of pleural effusion is diagnosed by a physician with the use of chest radiography, ultrasonography, or computed tomography. Although ultrasound becomes portable and handheld the diagnosis is possible only in the clinics or medical centers so far. The monitoring of pleural effusion in outpatients is still an unsolved problem.
So far, the use of near-infrared spectroscopy (NIRS) to test the amount of hydro-derivative fluids in various biomedical applications has been developed. For example, a method for assessing brain edema, water composition in rabbit meal, the water content in moisturizing creams or ceramic plasters has been published. In this work, the data form noninvasive NIRS measurement in patients with pleural effusion were collected. The method for noninvasive detection of pleural effusion using continuous-wave near-infrared spectroscopy is presented. The method has been developed based on numerical simulations of light transport in turbid media and validated on phantoms mimicking tissues and on patients with excess pleural fluid undergoing thoracocentesis.
Numerical simulations consisted in modeling light propagation in an optically turbid, non-homogeneous medium with tissue properties of peripulmonary structures and for various amounts of pleural fluid. A three-layer model depicting pleural effusion was adopted. It was assumed that the outer surface layer consists of skin, fat and muscle. Fiber optics were connected to this layer during measurements. Two fiber optics were used: one guiding the light from the source (emitter) and the second delivering to the spectrometer (detector). The second layer, present only when pleural effusion is present, is water layer. The third layer is the lung tissue layer. The NIRS measurement was performed in a reflective scenario.

胸腔积液是一种具有多种原发性疾病病因的医学状况，例如心血管疾病、肺脏疾病和肿瘤疾病。它是诸如肺炎、结核病、癌症、心力衰竭和炎症等疾病的副作用，这些疾病负责引发胸膜炎症性疾病。胸腔积液的晚期诊断会干扰呼吸功能，影响心脏手术，甚至可能导致胸膜腔内出血。在这种情况下，立即需要医疗干预和胸腔积液的引流或执行胸膜融合术，以使胸膜斑块融合，这是一项侵入性且可能危及生命的程序。因此，胸腔积液患者，尤其是那些反复发生胸腔积液的群体，应持续进行监测。在标准临床流程中，胸腔积液的存在是由医生通过胸部X光、超声波或计算机断层扫描进行诊断的。尽管超声波变得便携且便于手持，但目前诊断仅在诊所或医疗中心进行。门诊患者胸腔积液的监测仍然是一个未解决的问题。迄今为止，近红外光谱学（NIRS）在测试各种生物医学应用中的水衍生流体量方面已经得到了发展。例如，已发表了一种评估脑水肿、兔饲料中的水分含量、保湿霜或陶瓷膏中的水分含量的方法。在本研究中，收集了非侵入性NIRS测量胸腔积液患者的数据。该方法基于浑浊介质中光传输的数值模拟，并在模拟组织和进行胸腔穿刺的胸腔积液过多的患者身上进行了验证。数值模拟包括在具有周围肺结构组织特性的光学浑浊、非均匀介质中对光传播进行建模，并针对不同量的胸腔积液进行了建模。采用了一个三层模型来描述胸腔积液。假设外层表面层由皮肤、脂肪和肌肉组成。在测量过程中，光纤连接到这一层。使用了两个光纤：一个引导光源（发射器）的光，另一个将光传递到光谱仪（检测器）。第二层仅在存在胸腔积液时存在，是水层。第三层是肺组织层。NIRS测量是在反射场景中进行的。