Biomedical Optics Research Laboratory (BORL), Department of Neonatology, University of Zurich and University Hospital Zurich, Zürich, Switzerland.
Adv Exp Med Biol. 2024;1463:239-243. doi: 10.1007/978-3-031-67458-7_40.
Tissue mimicking optical phantoms are commonly used to calibrate or validate the performance of near-infrared spectroscopy or tomography. Human tissue is not only irregular in shape, but also exhibits dynamic behaviour, which can cause changes in optical properties. However, existing phantoms lack complex structures and/or continuously varying optical properties.
The project aimed to design, fabricate and characterise a novel phantom system for testing near-infrared imaging devices.
We designed a dynamic tissue-mimicking phantom platform which features arbitrary internal shapes and variable optical properties. The solid part of phantom was made of silicone material with absorbing and scattering properties similar to the brain. We printed a semi-ellipsoidal sphere (a major axis = 20 mm and a minor axis = the third axis = 12 mm) using a water-soluble material polyvinyl alcohol (PVA). The shape was placed at the depth of 5 mm in the silicone bulk. The desired internal hollow structure was formed after curing and submerging the phantom in water. The liquid part contained dyes and Intralipid. The optical properties within the internal shape were adjusted by injecting the liquid solutions of varying dye concentrations with a syringe pump at a constant rate. The phantom was measured by a frequency domain near-infrared spectroscopy (FD NIRS) and imaged by a time domain near-infrared optical tomography (TD NIROT).
A dynamic phantom system with a complex internal structure and varying optical properties was created. Changes in light intensity were detected by the FD NIRS. The internal structure of this phantom was accurately recovered by NIROT image reconstruction.
We successfully developed a novel phantom system with an internal complex shape and continuously adjustable optical properties. This phantom was accurately imaged using NIROT, and the changing light intensity was detected by NIRS. It is a valuable tool for validating optical technologies.
组织模拟光学体模常用于校准或验证近红外光谱或断层摄影术的性能。人体组织不仅形状不规则，而且还表现出动态行为，这可能导致光学性质发生变化。然而，现有的体模缺乏复杂的结构和/或连续变化的光学性质。
本项目旨在设计、制作和表征一种用于测试近红外成像设备的新型体模系统。
我们设计了一种具有任意内部形状和可变光学性质的动态组织模拟体模平台。体模的固体部分由具有与大脑相似的吸收和散射特性的硅酮材料制成。我们使用一种水溶性材料聚乙烯醇（PVA）打印出一个半椭圆形球体（长半轴=20 毫米，短半轴=第三轴=12 毫米）。将形状放置在硅酮块的 5 毫米深度处。在固化并将体模浸入水中后，形成所需的内部空心结构。液体部分包含染料和 Intralipid。通过以恒定速率用注射器泵注入具有不同染料浓度的液体溶液来调整内部形状内的光学性质。使用频域近红外光谱（FD NIRS）测量体模，并使用时域近红外光学断层摄影（TD NIROT）对其进行成像。
创建了具有复杂内部结构和可变光学性质的动态体模系统。FD NIRS 检测到光强的变化。NIROT 图像重建准确地恢复了该体模的内部结构。
我们成功开发了一种具有内部复杂形状和连续可调光学性质的新型体模系统。NIROT 准确地对该体模进行了成像，并通过 NIRS 检测到了变化的光强。它是验证光学技术的有价值的工具。
