Tamura R, Ishibashi T, Saito H, Majima K, Tsuda M, Takahashi S, Yamada S
Department of Radiology, Tohoku University, School of Medicine.
Nihon Igaku Hoshasen Gakkai Zasshi. 2000 Nov;60(13):738-45.
To report the feasibility of new duct caliber measurement methods using signal intensity on MR cholangiopancreatography (MRCP).
A phantom with 0.25-8 mm caliber ducts was imaged with a 1.5-Tesla MR system using the usual MRCP sequence. Each caliber was measured by conventional method (full width at half maximum, FWHM) and two new methods: the maximum intensity measurement method (MIM), in which caliber was calculated from maximum signal intensity, and the area intensity measurement method (AIM), in which caliber was calculated from the area under the signal intensity curve. Errors in calculated caliber were compared among the three methods of measurement.
Mean measurement errors of each caliber for 1-8 mm ducts by MIM [14% (2.1-25%)] and by AIM [6.8% (0.4-16%)] were significantly lower than those by FWHM [30% (17-64%)]. AIM was significantly more accurate than MIM for caliber measurement of ducts over 1 mm.
Two new caliber measurement methods for pancreatobiliary ducts in MRCP, MIM and AIM are accurate and should play an important role in clinical MRCP.
报告利用磁共振胰胆管造影（MRCP）上的信号强度测量胆管管径新方法的可行性。
使用1.5特斯拉MR系统，采用常规MRCP序列对具有0.25 - 8毫米管径的体模进行成像。每种管径通过传统方法（半高宽，FWHM）以及两种新方法进行测量：最大强度测量法（MIM），即根据最大信号强度计算管径；面积强度测量法（AIM），即根据信号强度曲线下的面积计算管径。比较三种测量方法计算出的管径误差。
对于1 - 8毫米的胆管，MIM [14%（2.1 - 25%）]和AIM [6.8%（0.4 - 16%）]测量各管径的平均误差显著低于FWHM [30%（17 - 64%）]。对于管径大于1毫米的胆管，AIM在管径测量方面比MIM显著更准确。
MRCP中用于胰胆管管径测量的两种新方法，MIM和AIM准确，应在临床MRCP中发挥重要作用。
