Single-pixel diffuse optical tomography scanner for dynamic functional imaging

用于动态功能成像的单像素漫反射光学断层扫描仪

• 批准号: RGPIN-2017-06337
• 负责人: Diop, Mamadou
• 金额: $ 1.53万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=678506
• 关键词: Single; pixel; diffuse; optical; tomography

Rational and Objective****Diffuse optical tomography (DOT) is a low-cost imaging modality that can provide three-dimensional (3D) images of tissue absorption, which, in the near-infrared range, is mainly due to hemoglobin and water. By measuring tissue absorption at multiple wavelengths, tomographic functional images can be generated and used to detect localized physiological abnormalities. It is this capacity to noninvasively image tissue physiological parameters (and to do so using safe, portable instruments) that makes DOT such an attractive technology. While DOT has numerous advantages, its widespread adoption as a functional imaging modality has been restricted by the current tradeoff between spatial and temporal resolution. That is, current methods can either acquire data at high speed with poor spatial resolution, or at millimeter resolution but with poor temporal resolution.****The objective of this research program is to address this critical limitation.****Research Plan****1) We will build a DOT scanner based on:**** i) Early-photons imaging: These photons travel along paths that are confined close to the line of sight between the source and detector (quasi-mimicking X-rays), which reduces image blurring and significantly improves spatial resolution.**** ii) Wide-field patterned illumination: A digital micro-mirror device (DMD), made of a 2D array of micro-mirrors that can be individually turned “ON” or “OFF”, will be used to generate wide-field patterned illumination on the surface of the tissue. We will leverage recent advances in DMDs technology that produced units that can generate light patterns at very high speed (up to 23 kHz) with high light output (up to 48%), to build a fast and efficient illumination system.*** iii) Compressive detection: Light transmitted through the tissue will be projected onto a 2nd DMD (to spatially encode the light intensity), then integrated by a single photodetector. Notice that we will be using a single-pixel camera to generate 3D images without scanning or multiplexing.****2) We will develop an image reconstruction software based on accurate Monte Carlo modeling of early-photons propagation in tissue.****3) The spatial resolution of the scanner will be quantified using tissue-mimicking phantoms with spatially-resolved features.****4) The dynamic imaging capability of the system will be tested in an animal model of localized ischemia.****Impact****The research program detailed in this proposal will lead to the development of a DOT scanner capable of fast 3D imaging of thick tissue (up to 60-mm thickness) with millimeter resolution. Such a scanner will enable dynamic imaging of molecular tracers to develop methods for i) small animal molecular imaging, ii) monitoring treatment response in inflammatory arthritis, and iii) predicting response to chemotherapy in breast cancer.***

理性和客观****弥漫性光学层析成像（DOT）是一种低成本成像，可以通过测量血红蛋白和水来吸收组织吸收，可以在近红外范围内吸收二维（3D）E吸收。在多个波长中，可以生成层析成像图像，并检测到局部的异常，而DOT则具有许多优势，因为它的广泛性是由于当前的折衷方案而限制了差异方法可以以较差的空间分辨率来高速数据，但时间分辨率较差。靠近源和检测器射线之间的视线），这会降低图像模糊并显着改善空间分辨率。为了在组织的表面上产生宽阔的照明，我们将利用DMDS技术的最新技术，以高光输出（最高48％）罐装光模式）系统。没有扫描或多重扫描。 *影响****该提案中详细介绍的研究计划将导致能够以毫米分辨率快速的Thissue（厚度高达60毫米）的DOT扫描仪的开发。 i）小动物分子成像，II监测炎症性关节炎的治疗反应，iii）预测乳腺癌的化学疗法的反应。