肠道准备减少3TMR前列腺弥散加权扫描磁化率伪影的评价

Evaluation of Bowel Preparation in Reducing Artifact of Prostate DWI at 3T MR System

目的评价肠道准备对前列腺受检者直肠内容物及其弥散加权扫描磁化率伪影的影响。资料与方法2010-10～2011-03连续对各30例行肠道准备和无肠道准备的受检者采用3TMR扫描仪行前列腺DWI扫描。所有图像分别由2位医师采用双盲法进行评价。结果无肠道准备组直肠内容物以气体为主及以液体为主的出现率分别为56.7%、43.5%;肠道准备组直肠内容物以气体为主及以液体为主的出现率分别为13.3%、86.7%,两组差异有统计学意义(χ2=12.381、17.778,P=0.00)。以液体为主的直肠内容物受检者精囊腺及前列腺磁化率伪影显示率和以气体为主的直肠内容物的受检者显示率分别为3.85%、82.75%(χ2=40.286、35.582,P=0.000)。结论肠道准备有助于减少直肠内容物的气体,从而减少前列腺及精囊腺图像磁化率伪影,提高图像质量,因此肠道准备是不可忽视的检查前步骤。

Purpose To evaluate the effects of bowel preparation on rectal content and susceptibility artifact of prostate DWI sequence at 3T system. Materials and Methods A total of 30 patients with bowel preparation and 30 patients without bowel preparation undertook prostate DWI examinations using 3T MR scanner from October 2010 to March 2011, and all the images were blindly evaluated by two experienced radiologists. Results The air-predominant rectal content appeared about 56.7%, and fluid-predominant content appeared 43.5% for no bowel preparation group; the air-predominant rectal content appeared 13.3%, and fluid-predominant rectal content appeared 86.7% for bowel preparation group. There was significantly difference between the two groups （χ2=12.381 or 17.778,P=0.00）. The susceptibility artifact of the prostate and seminal vesicles appeared 3.85% for those with fluid- predominant rectal content, while 82.75% for those with air- predominant rectal content（χ2=40.286 or 35.582,P=0.000）. Conclusion The bowl preparation can greatly reduce the air within the rectum, thus reducing the susceptibility artifact and improving the image quality of prostate DWI scan. The bowel preparation can not be neglected before prostate DWI scanning at 3T system.