電腦斷層在腦頸動脈攝影之掃描參數最佳化

Carotid and Cerebral CT Angiography by CT Scan-Optimization of the Scanning Parameters

李基訓(Chi-Hsin Lee) ； 丘思穎(See-Ying Chiou) ； 林新傑(Hsin-Chieh Lin) ； 李威興 ； 陳凱錡(Kai-Chi Chen) ； 賴善鳴(San-Ming Lai) ； 陳名聖(Ming-Sheng Chern)

《台灣應用輻射與同位素雜誌》 5卷3期 (2009/09) Pp. 729-734

https://doi.org/10.29832/TJARI.200909.0005

摘要

電腦斷層腦頸動脈攝影在臨床上對於診斷腦頸動脈疾病具有極高的診斷價值，而因電腦科技的進步，電腦斷層的速度以及功能不斷提昇之下，已可以克服早期在腦頸動脈檢查技術上必須分開掃描的缺點，並且使影像品質有顯著的改善，但就影像結果而言，還是有些問題，如頸動脈開口因上腔靜脈顯影劑濃度過高產生假影、整體腦頸動脈血管濃度不均勻，以及血管分枝或末端顯影不足或顯影過度而造成判讀困難。本研究取樣對象從2005年5月至2007年9月共收集20位受檢者影像9男性14位，女性6位，平均年齡55歲，將兩組影像交由2位放射專科醫師評分，再利用配對t檢定（雙尾分析）之統計方法，並將原始掃描參數作調整後之掃描影像與調整前做比較，來判斷調整參數對於影像品質改善的效果，結果掃描參數調整前平均分數爲3.88±0.77，掃描參數調整後平均分數爲4.48±0.48，且P值小於0.05的，表示此兩組數據有明顯統計上的意義，所得結果，調整掃描參數後對於整體影像品質有顯著的改善。目前調整後的掃描參數已成爲本中心的標準掃描參數，此掃描參數所得之影像，影像品質明顯比調整前改善許多，有助於醫師提昇判讀與診斷腦頸動脈疾病之能力。

關鍵字

電腦斷層腦頸動脈攝影 ； 電腦斷層

並列摘要

In clinical setting, for the diagnosis of pathology in the arterial system at head and neck, cerebral and carotid computed tomography (CT) angiography provides important information and is of high diagnostic value. The advances of computer technology and CT scanning capability have made it possible to scan the arterial system at head and neck during one acquisition time, which was not available in the past. The imaging quality is also improving. However, as for the images of cerebral and carotid CT angiography, there is still some pitfalls, such as the artifact at the carotid orifice caused by high concentration of contrast in the superior vena cava, the inhomogeneous density of the whole cerebral and carotid arterial system, the insufficient or excessive enhancement of the braches or terminal portion of arterial system. All the above can be associated with diffculty in imaging interpretation. This study enrolled 20 cases who underwent cerebral and carotid CT angiography, from May 2005 through September 2007, including 14 male and 6 female. The mean age is 55 years. Two sets of images with different scanning parameters were reviewed and scored by 2 radiologists. To evaluate the effect of the new modified scanning parameters, the scores were analyzed by paired test. The average of score for the images with the original scanning parameter was 3.88±0.77, and the average of score for the images with the new modified scanning parameter was 4.48±0.48. The statistics revealed a p value less than 0.55, which means there is significant difference in the scores of the two sets of images, and the new modified scanning parameters can significantly improve the imaging quality. At our institution, the scanning protocols have been modified to the new parameters, which can provide a better imaging quality help and benefit the interpretation and diagnosis of pathology in the arterial system at head and neck.

並列關鍵字

cerebral and carotid computed tomography angiography ； computed tomography