Appendicitis Computed Tomography Score: a Useful Tool for Predicting Perforation and Surgical Course of Acute Appendicitis
BMH Lai, CY Chu, BST Leung, VKP Fung, DTF Lee, THT Sung, JLS Khoo
Hong Kong J Radiol 2015;18:267-76
DOI: 10.12809/hkjr1515310
Objective: To investigate the utility of the Appendicitis Computed Tomography (ACT) scoring system in the diagnosis of perforated appendicitis and prediction of surgical outcome.
Methods: A retrospective study was conducted on 102 subjects who underwent computed tomography (CT) scan and appendectomy for acute appendicitis between May 2011 and January 2012. Images were reviewed for five individual CT signs (appendiceal wall defect, phlegmon, abscess, extraluminal gas, and extraluminal appendicolith) and a score (ACT score) was assigned for each patient based on the number of detectable findings. Correlation of ACT score and individual CT signs with appendiceal perforation and surgical outcome was evaluated statistically. Diagnostic power was assessed using receiving operating characteristic (ROC) curve.
Results: A total of 84 subjects were included in the final study after exclusion. ACT score was significantly higher for the perforated group compared with the non-perforated group (2.52 vs. 0.40, p < 0.001) and also higher for the open surgery group than the laparoscopic surgery group (2.78 vs. 0.93, p < 0.001). ACT score was an independent predictor of perforation (odds ratio [OR] = 7.05, p < 0.001), need for open surgery (OR = 2.99, p = 0.002), and operating time (increase of 12.93 minutes, p < 0.001). On ROC curves, ACT score showed a higher discriminating power for both appendiceal perforation (area under the curve [AUC] = 0.939) and need for open surgery (AUC = 0.858) than individual CT signs. An ACT score of 0 was 100% sensitive for excluding appendiceal perforation and open surgery in our study, whereas an ACT score of >3 was diagnostic for perforated appendix.
Conclusions: The ACT score is a practical and accurate tool for diagnosis of appendiceal perforation and prediction of surgical outcome.
中文摘要
闌尾炎CT評分：一個能預測急性闌尾炎穿孔和手術結果的有用工具
賴銘曦、朱志揚、梁肇庭、馮邦、李騰飛、宋咸東、邱麗珊
目的：探討闌尾炎電腦斷層掃描（ACT）評分系統對於診斷闌尾炎穿孔和預測手術結果的效用。
方法：回顧研究於2011年5月至2012年1月期間因急性闌尾炎而接受闌尾切除術，並接受電腦斷層掃描（CT）的102名患者。找出他們的CT影像是否有以下五項獨立特徵：闌尾壁缺損、蜂窩織炎、膿腫、闌尾腔外集氣和闌尾腔外結石；並按其出現特徵的數目給予評分（即ACT分數）。把ACT分數和獨立的闌尾穿孔CT特徵和手術結果的相關性進行了統計學評估。利用ROC曲線為評估其診斷功能。
結果：共84名病人被納入最後研究。闌尾穿孔患者的ACT分數顯著高於沒有穿孔的患者（2.52比0.40，p<0.001）；接受開腹手術患者的ACT分數顯著高於接受腹腔鏡手術的患者（2.78比0.93，p<0.001）。ACT分數是以下幾項的獨立預測因子：穿孔（比數比=7.05，p<0.001）、需進行開腹手術（比數比=2.99，p=0.002）和手術時間（增加了12.93分鐘，p<0.001）。經ROC曲線分析，ACT分數在闌尾穿孔（曲線下之區域=0.939）和需進行開腹手術（曲線下之區域=0.858）方面比獨立CT特徵有較高的辨識能力。本研究發現ACT分數為「零」時即可完全排除闌尾穿孔和開腹手術的可能性，而ACT分數高於3時可被診斷為闌尾穿孔。
結論：ACT分數是診斷闌尾穿孔和預測手術結果的一個既實用又準確的工具。