Ryu K N, Jaovisidha S, De Maeseneer M, Jacobson J, Sartoris D J, Resnick D
Department of Radiology, University of California, San Diego Veterans Affairs Medical Center 92161, USA.
Invest Radiol. 1997 Jan;32(1):7-11. doi: 10.1097/00004424-199701000-00002.
Lipohemarthrosis, the presence of fat and blood in a joint cavity, exhibits several complex layers related to differences in specific component relaxation on magnetic resonance (MR) images. The authors investigated sequential changes in the appearance of lipohemarthrosis of the knee as demonstrated by MR imaging.
Sequential MR imaging over a 4-day period was performed on two cadaveric knees after intraarticular injection of blood from a volunteer and fat from a cadaveric tibia (50 mL of blood and 25 mL of fat in one knee and 15 mL of blood and 5 mL of fat in the other knee). The authors determined components in the joint based on MR signal behavior. Magnetic resonance imaging examinations of four patients with intracapsular fractures and lipohemarthroses of the knee were reviewed retrospectively.
Sequential MR images of cadaveric knees showed serial changes representing progressive formation and lysis of blood clot. Several fluid-fluid levels (globules of fat at the interface between fat and blood) and entrapment of fat were early findings of lipohemarthrosis. Three different fluid levels appeared approximately 3 hours after injection of fresh blood and marrow fat. The 96-hour study demonstrated three distinct levels.
Lipohemarthrosis demonstrates temporal changes on MR imaging related to stages of formation and lysis of blood clot.
关节积脂血征，即关节腔内存在脂肪和血液，在磁共振（MR）图像上表现出与特定成分弛豫差异相关的几个复杂层面。作者研究了膝关节积脂血征在MR成像中的连续变化。
在向两具尸体膝关节内分别注射来自一名志愿者的血液和一具尸体胫骨的脂肪后（一个膝关节注射50毫升血液和25毫升脂肪，另一个膝关节注射15毫升血液和5毫升脂肪），在4天内对这两具尸体膝关节进行连续MR成像。作者根据MR信号表现确定关节内的成分。回顾性分析了4例膝关节囊内骨折合并积脂血征患者的磁共振成像检查结果。
尸体膝关节的连续MR图像显示了代表血凝块逐渐形成和溶解的系列变化。几个液-液平面（脂肪与血液界面处的脂肪球）和脂肪嵌顿是关节积脂血征的早期表现。注入新鲜血液和骨髓脂肪后约3小时出现三种不同的液平面。96小时的研究显示出三个不同的层面。
关节积脂血征在MR成像上表现出与血凝块形成和溶解阶段相关的时间变化。
