大腸鏡自動化概念之實現

Abstract

結腸內視鏡檢查為現行大腸相關疾病之視覺診察與治療的黃金標準。然而，大腸其鏡頭的大小與其純手動式的操作裝置，使得病人在接受內視鏡檢查時容易產生不適感。為了減輕病人的不適感，並提升醫師執行大腸鏡檢查的效率，自動化大腸鏡之概念因此孕育而生。本研究中欲將醫師推送大腸鏡的「前進」動作與轉動轉盤的「轉向」動作進行自動化，降低大腸鏡在人體內與腸壁之碰撞，並以自動化的機構提升檢查的品質與效率。本研究前後發展出兩代自動化大腸鏡，分別為「自動化大腸鏡-光纖感測型」與「自動化大腸鏡-影像處理型」。「自動化大腸鏡-光纖感測型」中，於大腸鏡前端的鏡頭處加裝數位光纖光學感測器，利用感測器回饋訊號至重組式輸入/輸出的嵌入式監控系統，進而透過此系統由伺服馬達對大腸鏡原配備之手動轉盤進行控制，帶動大腸鏡頭前端轉向，使大腸鏡能隨時自動導正回到腸道中央；同時藉由直流馬達之推動，讓大腸鏡能在腸道中自動前進，並利用旋轉編碼器之回饋與PID控制器，追蹤與控制大腸鏡前進之速度。「自動化大腸鏡-影像處理型」中，改變了採用之訊號與導入模糊控制理論，並使用附加裝置之概念，在完全不改變大腸鏡原配備的情況下完成了自動化之控制與馬達動力的傳遞。「自動化大腸鏡-影像處理型」中將大腸鏡檢查時，即時回傳的鏡頭影像傳至電腦做為訊號來源，因此不需要額外安裝感測器至大腸鏡上。在電腦進行影像處理分析，利用模糊控制理論模擬操縱者之經驗做為轉向訊號的產生。轉向訊號輸出至伺服馬達並利用外加的皮帶輪裝置將馬達動力傳遞至手動轉盤以帶動大腸鏡頭前端轉向。本研究成功試製兩代自動化大腸鏡雛型品，除了展示其基本轉向動作之控制外，並以100公分長之腸道模型為基準進行實驗，自動化之大腸鏡皆能在不到1分鐘內不碰到大腸腸壁的情況下完成全程。

Colonoscopy is the current gold standard for visual diagnosis and treatment of colon-related diseases. However, the size of the colonoscope, combined with the non-automatic nature of the device, can often cause discomfort to patients during examination. To reduce the burden for patients and allow physicians to conduct the examination more efficiently, an automated colonoscope concept is proposed. The aim of this study is to automatize “forward movement” and” turning movement”, now conducted by physicians, so as to reduce the risk of collision between colonoscope and intestinal wall, and enhance the quality and efficiency of colonoscope examination by automated device. Two types of automated colonoscope were developed, categorized as “Automated Colonoscope-FOS” and “Automated Colonoscope-IMP”. In “Automated Colonoscope-FOS”, fiber optic sensors (FOS) mounted at the tip of the colonoscope measure the distance from the intestinal wall in two directions. The signals from these sensors are then fed into a reconfigurable input/output (RIO) control module to drive a motor-dial assembly that controls the movement of the tip of the colonoscope, therefore the tip of the colonoscope will always aim at the center of colon. Two DC motors connected to two rollers spinning in opposite directions automatically advance the colonoscope inside the colon. DC motors are attached by rotatory encoders, sent signals to PID controller, so as to realize forward velocities tracing. In “Automated Colonoscope-IMP”, fiber optic sensors signals were replaced by image processing signals (IMP), captured in time by the CCD camera in the tip of the colonoscope. The signals from image processing are manipulated by fuzzy logic control to determine the turned-angles of motor-dial assembly, constructed by belt and pulley. Moreover, to keep the original colonoscope device unchanged, attachment design is introduced. Results show that these two automated colonoscope prototypes are able to repeatedly advance inside a 100-cm-long in vitro simulation model in less than a minute without contacting the model wall.