皮瓣手術後血管阻塞之紅外線監控技術

Abstract

口腔癌是目前發生率及死亡率成長速度最快的癌症，在切除腫瘤之後，需利用身體其他組織來填補傷口，因此，皮瓣手術成了目前口腔重建中最常見之技術。然而，若是血管阻塞導致皮瓣重建失敗，則需要重新進行手術補救壞死皮瓣。臨床上用來監控皮瓣手術後血管阻塞情況之方法多為醫護人員進行常規檢查，但其過度倚賴護理人員的經驗，而其他方法，如：雷射都卜勒、彩色都卜勒超音波及近紅外線光譜儀，則因為需貼附皮瓣或是耗材昂貴有其限制，目前臨床尚未發展出一無須貼附皮瓣即能有效監控之技術。 本研究提出一紅外線監控技術做為監控皮瓣手術後血管阻塞情況之工具，因紅外線具備非侵入性、低成本、無放射性、快速及可以反覆成像的特性之外，最重要的是能夠在不接觸皮瓣表面即可量測其組織溫度，因此紅外線影像被視為具有潛力來監控皮瓣手術後血管阻塞情況之醫學影像技術。 本研究發展之演算法捕捉波長為7-14μm之光子，並利用薄板仿樣法(Thin-plate spline, TPS)來進行影像對位，將不同時間拍攝之不同姿勢的影像對應在一起，並採用特徵值分析(Eigenvalue analysis)演算法觀察動物實驗夾住血管模擬阻塞情況時的溫度隨著時間變化之分散程度，找出其可能阻塞之警訊，並針對具有發燒反應之案例進行因素分析(Factor Analysis)演算法，進而得到其對應之阻塞時間區段。本研究之動物實驗結果可以證明，當動脈或是靜脈阻塞時，皮瓣表面溫度會有下降的情形，而因素分析能夠有效偵測到阻塞之時間區段。

Oral cancer is currently one of the fastest growing cancers in terms of occurrence and mortality rate. After removal of the tumor, there’s a need to use other body tissues to fill the wound. Therefore, flap surgery has currently become the most common technique in oral reconstruction. However, if a vascular occlusion happens, it would lead to flap reconstruction failure and there would be a need for a re-surgical remedy for flap necrosis. The most common clinical method for monitoring flap pedicle thrombosis, after free flap surgery, is conventional monitoring by medical personnel; but it’s heavily reliant on the experience of the person in charge. Other methods, such as: Laser Doppler, Color Doppler Sonography and Near-Infrared Spectroscopy have its limitations, because of measuring the surface temperature need to attach to the flap or expensive consumables. Currently, an effective system for monitoring flap pedicle thrombosis after free flap surgery is not available. This study proposes an infrared approach for monitoring of flap pedicle thrombosis after free flap surgery. Infrared modality has such advantages as: being non-invasive, lower costing, non-radioactive, fast and repeatable monitoring. The most notable advantage is that it does not attach to the flap and can measure the surface temperature of their tissue. Therefore, infrared imagine has the potential to monitor flap pedicle thrombosis after free flap surgeries. The algorithms of this study development is captures the IR photon information from the infrared cameras. It used Thin-plate spline (TPS) for infrared image registration and the captured images of different positions correspond to different time points. Eigenvalue analysis algorithms used to observe the degree of dispersion with the time change of clamping vascular to simulate the occlusion in animal study. Find out the possible time points of occlusion and gave the alarm. Factor analysis algorithms is mainly aimed at the case has a fever reaction. Then get the corresponding time zone of occlusion. Animal experiments results of this study can be proved, flap temperature decreased due to artery or vein occlusion and factor analysis algorithms can effectively detect time zone of occlusion.