Patil Chetan A, Kirshnamoorthi Harish, Ellis Darrel L, van Leeuwen Ton G, Mahadevan-Jansen Anita
Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 137235, USA.
Lasers Surg Med. 2011 Feb;43(2):143-51. doi: 10.1002/lsm.21041.
The current standard for diagnosis of skin cancers is visual inspection followed by biopsy and histopathology. This process can be invasive, subjective, time consuming, and costly. Optical techniques, including Optical Coherence Tomography (OCT) and Raman Spectroscopy (RS), have been developed to perform non-invasive characterization of skin lesions based on either morphological or biochemical features of disease. The objective of this work is to report a clinical instrument capable of both morphological and biochemical characterization of skin cancers with RS-OCT.
The portable instrument utilizes independent 785 nm RS and 1,310 nm OCT system backbones. The two modalities are integrated in a 4″ (H) × 5″(W) × 8″(L) clinical probe. The probe enables sequential acquisition of co-registered OCT and RS data sets. The axial response of the RS collection in the skin was estimated using scattering phantoms. In addition, RS-OCT data from patients with cancerous and non-cancerous lesions are reported.
The RS-OCT instrument is capable of screening areas as large as 15 mm (transverse) by 2.4 mm (in depth) at up to 8 frames/second with OCT, and identifying locations to perform RS. RS signal is collected from a 44 µm transverse spot through a depth of approximately 530 µm. RS-OCT data sets from a superficial scar and a nodular BCC are reported to demonstrate the clinical potential of the instrument.
The RS-OCT instrument reported here is capable of morphological and biochemical characterization of cancerous skin lesions in a clinical setting. OCT can visualize microstructural irregularities and perform an initial morphological analysis of the lesion. The images can be used to guide acquisition of biochemically specific Raman spectra. The two data sets can then be evaluated with respect to one another to take advantage of the mutually complimentary nature of RS and OCT.
目前皮肤癌的诊断标准是目视检查，随后进行活检和组织病理学检查。这个过程可能具有侵入性、主观性、耗时且成本高昂。已经开发出包括光学相干断层扫描（OCT）和拉曼光谱（RS）在内的光学技术，以基于疾病的形态学或生化特征对皮肤病变进行非侵入性表征。这项工作的目的是报告一种能够利用RS-OCT对皮肤癌进行形态学和生化表征的临床仪器。
该便携式仪器采用独立的785 nm RS和1310 nm OCT系统主干。这两种模式集成在一个4英寸（高）×5英寸（宽）×8英寸（长）的临床探头中。该探头能够顺序采集配准的OCT和RS数据集。使用散射体模估计皮肤中RS采集的轴向响应。此外，还报告了来自患有癌性和非癌性病变患者的RS-OCT数据。
RS-OCT仪器能够以高达每秒8帧的速度对最大15毫米（横向）×2.4毫米（深度）的区域进行OCT筛查，并确定进行RS的位置。RS信号通过约530微米的深度从44微米的横向光斑采集。报告了来自浅表瘢痕和结节性基底细胞癌的RS-OCT数据集，以证明该仪器的临床潜力。
本文报道的RS-OCT仪器能够在临床环境中对癌性皮肤病变进行形态学和生化表征。OCT可以可视化微观结构不规则性，并对病变进行初步形态学分析。这些图像可用于指导生化特异性拉曼光谱的采集。然后可以相互评估这两个数据集，以利用RS和OCT相互补充的特性。
