1 Department of Radiology, Taean-gun Health Center and County Hospital, Taean-eup, Taean-gun, Chungcheongnam-do, Republic of Korea.
2 Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Republic of Korea.
AJR Am J Roentgenol. 2018 Sep;211(3):W140-W150. doi: 10.2214/AJR.17.19321. Epub 2018 Jul 24.
The purpose of the present study is to assess the visibility of the normal appendix on CT, MRI, or ultrasound (US) images of a healthy population.
The MEDLINE and EMBASE databases were searched to identify articles on the rates of detection of a normal appendix on CT, MRI, or US that appeared in the literature published up to January 20, 2017. Pooled detection rates were assessed using random-effects modeling, and rates associated with different imaging modalities were compared. Meta-regression analyses were performed to assess factors influencing detection rates and heterogeneity.
Thirty-two studies (21 CT studies with 5296 patients, 7 MRI studies with 600 patients, and 4 US studies with 1221 patients) were included in our meta-analysis. The overall normal appendix detection rate tended to be highest for CT (84%), followed by US (71%) and MR (69%), but no statistically significant differences were noted (for CT vs MRI, p = 0.16; for CT vs US, p = 0.23; and for MRI vs US, p = 0.91). Meta-regression analyses of the appendix detection rate with CT revealed that the year of publication of the study, the number of CT channels, and slice thickness affected study heterogeneity.
Normal appendixes seemed to be more visible on CT than on MRI or US, although this finding did not have statistical significance. With respect to CT, detection of normal appendixes was significantly better when more channels and thinner slices were used.
本研究旨在评估正常阑尾在 CT、MRI 或超声（US）图像中的可见性。
检索 MEDLINE 和 EMBASE 数据库，以确定截至 2017 年 1 月 20 日发表的文献中关于 CT、MRI 或 US 上正常阑尾检出率的文章。使用随机效应模型评估汇总检出率，并比较不同成像方式的检出率。进行荟萃回归分析以评估影响检出率和异质性的因素。
我们的荟萃分析纳入了 32 项研究（21 项 CT 研究，5296 例患者；7 项 MRI 研究，600 例患者；4 项 US 研究，1221 例患者）。总体而言，CT 检查的正常阑尾检出率最高（84%），其次是 US（71%）和 MRI（69%），但差异无统计学意义（CT 与 MRI 比较，p = 0.16；CT 与 US 比较，p = 0.23；MRI 与 US 比较，p = 0.91）。CT 检查阑尾检出率的荟萃回归分析表明，研究的发表年份、CT 通道数和层厚影响了研究的异质性。
正常阑尾在 CT 上似乎比在 MRI 或 US 上更可见，尽管这一发现没有统计学意义。就 CT 而言，使用更多通道和更薄的切片可以显著提高正常阑尾的检出率。
