內視鏡導管式光學同調斷層掃描術於子宮頸癌臨床應用之可行性研究

Abstract

本論文致力於開發與驗證可應用於婦科臨床的導管式光學同調斷層掃描術（Optical Coherence Tomography, OCT）系統。根據對婦科應用中不同的成像需求，設計了前掃式與側掃式兩種成像探頭，以對應子宮頸口表面與子宮頸內管腔道組織的影像擷取。本系統硬體亦為臨床應用做準備進行設計，針對側掃式系統，對光學元件的部分進行模組化設置，並設計了專屬光學台車以整合所需儀器；而針對前掃式系統則引入了OCT引擎，將整套系統輕量化以縮小體積，提升便攜性與臨床部署能力。OCT系統特性方面，另外搭建一組不具掃描成像功能的客製化樣本臂，以特定長度單模光纖及其經平面切割的光纖端面構成，模擬導管的光學路徑，用於側掃式導管系統的特性量測。實驗獲得 106.9 dB 的高靈敏度，並顯示出成像範圍內良好的系統穩定度，確保整體成像穩定性與重複性。我們使用前掃式及側掃式兩套系統對膠帶以及人類指尖與口腔黏膜進行OCT成像，影像結果分別展示了各樣本的結構特徵，並且這些影像成功顯示出所開發之OCT成像系統於婦科臨床應用的可行性。此外，為減輕導管式OCT系統中常見的偏振相關成像雜訊，該導管式OCT成像系統架構內整合了偏振分光偵測模組(Polarization diversity module, PDM)，透過合併正交偏振訊號，有效抑制偏振偽影並提升影像品質。本研究更進一步將側掃式導管OCT系統進行硬體改裝，以實現導管式之偏振靈敏光學同調斷層掃描術(Polarization-sensitive OCT, PS-OCT)，利用電光調變器(Motorized delay-line, MDL)來動態控制入射光偏振態，以提取樣本組織中雙折射與去偏振特性。同時，本研究已擬定完整的婦科臨床實驗流程，包括影像量測計畫與受試者同意書，預期可應用於病患在近距放射治療(Brachytherapy)前後的子宮頸組織觀察與變化分析。

This thesis focuses on the development and validation of catheter-based optical coherence tomography (OCT) systems designed for clinical applications in gynecology. To address the distinct imaging requirements in gynecological examinations, two types of probes with forward-viewing and side-viewing configurations were developed. The hardware design of both systems was tailored for clinical deployment. The side-viewing OCT system featured optical modularization and a dedicated optical cart for instrument integration, while the forward-viewing OCT system incorporated an OCT engine to reduce system size and enhance portability. For system characterization, a customized sample arm without scanning functionality was additionally constructed, consisting of a single-mode fiber of specific length with a flat-cleaved end face, to replicate the optical path of the catheter and enable characterization of the side-viewing OCT system. The measured sensitivity of the system reached 106.9 dB and demonstrated excellent imaging stability, ensuring robust and repeatable image acquisition. Imaging experiments using both probe types were conducted on a tape phantom, human fingertips, and oral mucosa. The resulting OCT images clearly revealed microstructural features of each sample and validated the system’s feasibility for gynecological imaging applications. To mitigate polarization artifacts commonly observed in catheter-based OCT, a polarization diversity module was integrated. By combining orthogonal polarization signals, the system effectively suppressed artifacts and improved image quality. Furthermore, the side-viewing OCT system was modified to implement polarization-sensitive OCT (PS-OCT), enabling the extraction of tissue birefringence and depolarization properties through dynamic polarization modulation using an electro-optic modulator. In preparation for the clinical experiment, a complete imaging protocol and informed consent documents were drafted. The proposed system thus demonstrates strong potential as a multifunctional imaging tool for advanced gynecological diagnostics.