Hirai Toshinori, Sasaki Makoto, Maeda Masayuki, Ida Masahiro, Katsuragawa Shigehiko, Sakoh Masaharu, Takano Koichi, Arai Shoichi, Hirano Teruyuki, Kai Yutaka, Kakeda Shingo, Murakami Ryuji, Ikeda Ryuji, Fukuoka Hirofumi, Sasao Akira, Yamashita Yasuyuki
Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
Acad Radiol. 2009 Mar;16(3):305-12. doi: 10.1016/j.acra.2008.09.012.
When evaluating ischemic stroke on diffusion-weighted magnetic resonance imaging (DWI), the display method has not been investigated. The purpose of this study was to determine whether standardization of the display method for DWI affects observers' diagnostic performance in detecting ischemic stroke on DWI.
Twenty-six observers evaluated 40 DWI studies in 20 patients with acute (< 6 hours) middle cerebral arterial strokes and 20 controls for the presence of hyperintense lesions in 10 areas using the Alberta Stroke Programme Early CT Score (ASPECTS) system and one area in the corona radiata using a modified version of the ASPECTS system (ASPECTS-DWI). The images were reviewed using a standardized display method (SDM) and a conventional display method (CDM). The reading time was recorded for each session. The observers' performance was evaluated with receiver-operating characteristic analysis.
In all observers with ASPECTS-DWI scores of < or = 8 points, the value of the mean average area under the receiver-operating characteristic curve was slightly higher for the SDM than the CDM, but the difference was not statistically significant. In the insular ribbon, diagnostic accuracy was significantly higher with the SDM than the CDM (P = .036). In the other locations, there were no significant differences. With the SDM, the mean reading time was reduced by 7.5 seconds (P = .024).
The SDM improved diagnostic accuracy for the insular ribbon and shortened the reading time, although it did not improve observers' performance with the ASPECTS-DWI system.
在通过扩散加权磁共振成像（DWI）评估缺血性卒中时，尚未对显示方法进行研究。本研究的目的是确定DWI显示方法的标准化是否会影响观察者在DWI上检测缺血性卒中的诊断性能。
26名观察者使用阿尔伯塔卒中项目早期CT评分（ASPECTS）系统对20例急性（<6小时）大脑中动脉卒中患者和20例对照的40项DWI研究进行评估，以检测10个区域的高信号病变，并使用ASPECTS系统的改良版（ASPECTS-DWI）检测放射冠中的一个区域。图像采用标准化显示方法（SDM）和传统显示方法（CDM）进行回顾。记录每次检查的阅读时间。通过受试者操作特征分析评估观察者的表现。
在所有ASPECTS-DWI评分为≤8分的观察者中，SDM的受试者操作特征曲线下平均面积值略高于CDM，但差异无统计学意义。在岛叶带，SDM的诊断准确性显著高于CDM（P = 0.036）。在其他位置，无显著差异。使用SDM时，平均阅读时间减少了7.5秒（P = 0.024）。
SDM提高了岛叶带的诊断准确性并缩短了阅读时间，尽管它并未改善观察者使用ASPECTS-DWI系统的表现。
