Ecclestone Benjamin R, Bell Kevan, Abbasi Saad, Dinakaran Deepak, Taher Muba, Mackey John R, Haji Reza Parsin
PhotoMedicine Labs, Department of Systems Design Engineering, University of Waterloo, 200 University Ave W, Waterloo, Ontario, N2L 3G1, Canada.
illumiSonics, Inc., Department of Systems Design Engineering, University of Waterloo, 200 University Ave W, Waterloo, Ontario, N2L 3G1, Canada.
Biomed Opt Express. 2020 Dec 24;12(1):654-665. doi: 10.1364/BOE.405869. eCollection 2021 Jan 1.
Mohs micrographic surgery (MMS) is a precise oncological technique where layers of tissue are resected and examined with intraoperative histopathology to minimize the removal of normal tissue while completely excising the cancer. To achieve intraoperative pathology, the tissue is frozen, sectioned and stained over a 20- to 60-minute period, then analyzed by the MMS surgeon. Surgery is continued one layer at a time until no cancerous cells remain, meaning MMS can take several hours to complete. Ideally, it would be desirable to circumvent or augment frozen sectioning methods and directly visualize subcellular morphology on the unprocessed excised tissues. Employing photoacoustic remote sensing (PARS) microscopy, we present a non-contact label-free reflection-mode method of performing such visualizations in frozen sections of human skin. PARS leverages endogenous optical absorption contrast within cell nuclei to provide visualizations reminiscent of histochemical staining techniques. Presented here, is the first true one to one comparison between PARS microscopy and standard histopathological imaging in human tissues. We demonstrate the ability of PARS microscopy to provide large grossing scans (>1 cm, sufficient to visualize entire MMS sections) and regional scans with subcellular lateral resolution (300 nm).
莫氏显微外科手术（MMS）是一种精确的肿瘤治疗技术，通过术中组织病理学检查对组织层进行切除和检查，以尽量减少正常组织的切除，同时完全切除癌症病灶。为了实现术中病理检查，组织会在20到60分钟内被冷冻、切片和染色，然后由MMS外科医生进行分析。手术会一层一层地持续进行，直到没有癌细胞残留，这意味着MMS手术可能需要几个小时才能完成。理想情况下，最好能规避或改进冷冻切片方法，并直接在未经处理的切除组织上可视化亚细胞形态。利用光声遥感（PARS）显微镜，我们提出了一种非接触式无标记反射模式方法，用于在人体皮肤冷冻切片中进行此类可视化。PARS利用细胞核内的内源性光吸收对比度，提供类似于组织化学染色技术的可视化效果。本文展示了PARS显微镜与人体组织标准组织病理学成像之间的首次真正的一对一比较。我们证明了PARS显微镜能够提供大面积扫描（>1厘米，足以可视化整个MMS切片）和具有亚细胞横向分辨率（300纳米）的区域扫描。
