電腦斷層大腸攝影對於大腸病灶之應用

The Application of CT Colongraphy of Colon Lesion

劉冠忻(Kuan-His Liu) ； 李正輝(Cheng-Hui Lee) ； 喻仲春(Cheng-Wen Liu) ； 盧建利(Chung-Chun Yu) ； 呂坤木(Kun-Mu Lu) ； 吳金珠 ； 陳良光(Liang-Kuang Chen) ； 蘇誠道(Chen-Dau Su)

《加馬》 37期 (2006/06) Pp. 53-60

https://doi.org/10.30173/JG.200606.0007

摘要

由於科技的進步，電腦斷層攝影由以前的單一切面螺旋式電腦掃描，進步至多切面(multi-slice)，並朝向體積式電腦斷層掃描的方式邁進，不僅由於切面變細提高解析度，更由於掃描與組像的速度增進，有效地克服因病人無法合作閉氣所產生的假影，三度空間成像或多方位影像重組技術，我們可以提高影像品質，此外應用於三度空間攝影後處理技術，我們得以建構虛擬內視鏡的影像篩選病人，減少非必要性的較侵襲性內視鏡檢查。
虛擬大腸鏡是最新的影像診斷技術。它以超快速螺旋電腦斷層及電腦虛擬的影像來檢查充滿空氣的大腸。可使用於診斷大腸瘜肉,大腸癌,及大腸憩室等疾病。與傳統的大腸內視鏡比較，虛擬大腸鏡的優點是安全，只需在肛門放置一條小管，不須像內視鏡般通過整條大腸﹔此外，經電腦技術組合的圖像可以順行或逆行，不會因為腫瘤阻塞而無法顯示前面的大腸，傳統的內視鏡只能向前順行，當遇上腫瘤或其他阻塞便無法前行。
虛擬大腸鏡具有可避免大腸內視鏡因重複使用檢體夾或消毒不完全所導致血液感染之可能性同時降低大腸鋇劑攝影在檢查過程中需灌入高對比顯影劑時所導致腫瘤或腸道破裂之風險，因此虛擬大腸內視鏡不失為一項既安全又為低危險性之檢查。本文目的是應用電腦斷層大腸攝影以偵測大腸病兆，並藉由虛擬大腸鏡與大腸鋇劑攝影及大腸內視鏡做比較，以方便評估是否可以取代及其可行性。

關鍵字

虛擬大腸鏡 ； 大腸內視鏡 ； 大腸鋇劑攝影

並列摘要

As the technological revolution, CT undergo continue development and evolved from single slice spiral scanner to multislice scanner. Further generations will be based on volumetric CT technology. Multislice CT provides higher scanner performance that can be used to thinner section, reduce scan time and longer ranges to reduce the motion or respiratory artifact, especially in uncooperation patients. Furthermore, It truly transforms CT from a transaxial cross-sectional modality into multiplanar reformation and various types of 3D imaging and basis for an expanding variety of 3D visualization techniques to develop virtual endoscopy. We can suggest virtual colonoscopy as screening tool for colorectal entity to reduce unnecessary of invasive colonoscopy examination.
Virtual colonoscopy is a newest and recently developed techniques that use an ultrafast spiral CT scanner and computer virtual reality software to look fully air filled colon and detect of polyp, colorectal neoplasm and diverticular disease. As compared with conventional colonoscopy, there are numerous benefits of virtual colonoscopy over conventional colonoscopy. It is a more comfortable without having to insert a long tube into the colon. Unlike the conventional colonoscopy, virtual colonoscopy dose not have the limitation of view direction. By providing both direct antegrade and retrograde visualization, virtual colonoscopy allows detection of abnormality proximal to obstruction segment. It is a safe, non-incasive study without infection and perforation risk. The aim of this study was to compare the detection accuracy of CT colonography and virtual colonoscopy with conventional colonoscopy and double contrast barium enema study and discuss the virtual colonoscopy may or may not prove to be alternative to diagnostic colonoscopy or barium enema study.