Department of Radiology, Uludağ University School of Medicine, Bursa, Turkey.
Diagn Interv Radiol. 2012 Jan-Feb;18(1):11-9. doi: 10.4261/1305-3825.DIR.4092-10.1. Epub 2011 Feb 23.
The aim of our study was to assess the contribution of various magnetic resonance imaging (MRI) sequences in determining the type of perianal fistula and in obtaining critical information for surgical decisions, as well as to define the optimal combination of sequences for readers with varying levels of experience.
The study included 33 MRI examinations in 26 patients with suspected perianal fistula. The following sequences were obtained in both the coronal and axial planes: thin slice, high resolution T1-weighted (W) spin echo; T2-weighted turbo spin echo; short tau inversion recovery (STIR); and native and contrast enhanced T1-weighted gradient echo fast low-angle shot (FLASH) images with fat suppression (FS-CE-T1W-GRE). The examinations were interpreted by three radiologists with varying degrees of experience in two different sessions, and the inter-reader agreement was assessed. Seventeen of the patients underwent surgery. The agreement between the surgical findings and the MRI results were evaluated.
A statistically significant concordance between the fistula classification and surgery was achieved with the FS-CE-T1W-GRE sequence for Reader 1 (Cramer's V=0.701, P = 0,022) and Reader 3 (Cramer's V=0.716, P = 0,043). For Reader 2, statistically significant concordance between fistula classification and surgery was achieved with the FS-CE-T1W-GRE (Cramer's V=0.703, P = 0,011) and the T2W images (Cramer's V=0.648, P = 0,027). For all sequences, there was statistically significant agreement between readers for fistula classification, internal opening location, and the presence of sinus tracts, abscess, a horseshoe component, and inflammation.
For experienced readers, combining FS-CE-T1W-GRE images with either T2W or STIR images collected in both the coronal and axial planes was sufficient to make an assessment before deciding the surgical extent of the procedure.
本研究旨在评估各种磁共振成像（MRI）序列在确定肛门周围瘘管类型和获取手术决策所需关键信息方面的作用，以及为不同经验水平的读者定义最佳序列组合。
本研究纳入 26 例疑似肛门周围瘘管患者的 33 次 MRI 检查。在冠状面和轴面均获得以下序列：薄层、高分辨率 T1 加权（W）自旋回波；T2 加权涡轮自旋回波；短反转时间反转恢复（STIR）；以及同/异相位增强 T1 加权梯度回波快速小角度激发（FLASH）脂肪抑制（FS-CE-T1W-GRE）图像。由三位具有不同经验水平的放射科医生在两个不同的时段进行阅片，评估读者间的一致性。其中 17 例患者接受了手术。评估手术结果与 MRI 结果的一致性。
对于 Reader 1（Cramer's V=0.701，P=0.022）和 Reader 3（Cramer's V=0.716，P=0.043），FS-CE-T1W-GRE 序列在瘘管分类与手术之间具有统计学显著的一致性。对于 Reader 2，FS-CE-T1W-GRE（Cramer's V=0.703，P=0.011）和 T2W 图像（Cramer's V=0.648，P=0.027）在瘘管分类与手术之间具有统计学显著的一致性。对于所有序列，读者在瘘管分类、内口位置以及窦道、脓肿、马蹄形成分和炎症的存在方面均具有统计学显著的一致性。
对于有经验的读者，结合冠状面和轴面采集的 FS-CE-T1W-GRE 图像与 T2W 或 STIR 图像，足以在决定手术范围之前进行评估。
