Schneider Crispin, Nikitichev Daniil, Xia Wenfeng, Gurusamy Kurinchi, Desjardins Adrien E, Davidson Brian R
University College London, Division of Surgery and Interventional Science, Royal Free Campus, London, United Kingdom.
University College London, Wellcome/EPSRC Centre for Surgical and Interventional Sciences, London, United Kingdom.
J Med Imaging (Bellingham). 2020 Nov;7(6):066001. doi: 10.1117/1.JMI.7.6.066001. Epub 2020 Dec 23.
Alterations in the optical absorption behavior of liver tissue secondary to pathological processes can be evaluated by multispectral analysis, which is increasingly being explored as an imaging adjunct for use in liver surgery. Current methods are either invasive or have a limited wavelength spectrum, which restricts utility. This proof of concept study describes the development of a multispectral imaging (MSI) method called multispectral tissue mapping (MTM) that addresses these issues. The imaging system consists of a tunable excitation light source and a near-infrared camera. Following the development stage, proof of concept experiments are carried out where absorption spectra from colorectal cancer liver metastasis (CRLM), hepatocellular carcinoma (HCC), and liver steatosis specimen are acquired and compared to controls. Absorption spectra are compared to histopathology examination as the current gold standard for tissue assessment. Generalized linear mixed modeling is employed to compare absorption characteristics of individual pixels and to select wavelengths for false color image processing with the aim of visually enhancing cancer tissue. Analysis of individual pixels revealed distinct absorption spectra therefore suggesting that MTM is possible. A prominent absorption peak at 1210 nm was found in lipid-rich animal tissues and steatotic liver specimen. Liver cancer tissue had a heterogeneous appearance on MSI. Subsequent statistical analysis suggests that measuring changes in absorption behavior may be a feasible method to estimate the pixel-based probability of cancer being present. In CRLM, this was observed throughout 1100 to 1700 nm, whereas in HCC it was concentrated around 1140 and 1430 nm. False color image processing visibly enhances contrast between cancer and normal liver tissues. The system's ability to enable no-touch MSI at 1100 to 1700 nm was demonstrated. Preliminary data suggest that MTM warrants further exploration as a potential imaging tool for the detection of liver cancer during surgery.
继发于病理过程的肝组织光吸收行为改变可通过多光谱分析进行评估，多光谱分析正越来越多地被探索作为肝脏手术中的一种成像辅助手段。目前的方法要么具有侵入性，要么波长光谱有限，这限制了其应用。这项概念验证研究描述了一种名为多光谱组织映射（MTM）的多光谱成像（MSI）方法的开发，该方法解决了这些问题。成像系统由一个可调谐激发光源和一个近红外相机组成。在开发阶段之后，进行了概念验证实验，获取了结直肠癌肝转移（CRLM）、肝细胞癌（HCC）和肝脂肪变性标本的吸收光谱，并与对照组进行比较。将吸收光谱与作为组织评估当前金标准的组织病理学检查进行比较。采用广义线性混合模型来比较单个像素的吸收特征，并选择用于伪彩色图像处理的波长，目的是在视觉上增强癌组织。对单个像素的分析揭示了不同的吸收光谱，因此表明MTM是可行的。在富含脂质的动物组织和脂肪变性肝标本中发现了1210nm处的一个突出吸收峰。肝癌组织在MSI上呈现出异质性外观。随后的统计分析表明，测量吸收行为的变化可能是估计基于像素的癌症存在概率的一种可行方法。在CRLM中，在1100至1700nm范围内均观察到这种情况，而在HCC中，它集中在1140和1430nm左右。伪彩色图像处理在视觉上增强了癌组织与正常肝组织之间的对比度。证明了该系统在1100至1700nm范围内实现非接触式MSI的能力。初步数据表明，MTM作为手术中检测肝癌的潜在成像工具值得进一步探索。
