Schweitzer M E, White L M
Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107, USA.
Radiology. 1996 Mar;198(3):851-3. doi: 10.1148/radiology.198.3.8628882.
To determine if altered weight bearing causes the appearance of marrow edema on magnetic resonance (MR) images.
Twelve volunteers underwent MR imaging with a short inversion time inversion-recovery (STIR) sequence at 1.5 T. The hips, knees, ankles, and feet were evaluated before and 2 weeks after altered weight bearing achieved with overpronation of one foot. Three volunteers underwent imaging a third time, 2 weeks after overpronation was stopped. Two observers assessed the images for evidence of marrow edema.
Changes were seen on images in 11 volunteers; the overpronated side only was affected in 10. Most changes occurred in the foot followed by the tibia and the femur. Most changes were a diffuse increase in marrow edema. In two volunteers, the changes resembled those of stress fractures.
Altered weight bearing should be added to the list of causes of increased medullary signal intensity (ie, marrow edema) on MR images.
确定负重改变是否会导致磁共振（MR）图像上出现骨髓水肿。
12名志愿者在1.5T磁场下采用短反转时间反转恢复（STIR）序列进行MR成像。在单足过度内旋导致负重改变之前和之后2周，对髋部、膝部、踝部和足部进行评估。3名志愿者在过度内旋停止2周后进行第三次成像。两名观察者评估图像以寻找骨髓水肿的证据。
11名志愿者的图像出现了变化；其中10名仅过度内旋侧受到影响。大多数变化发生在足部，其次是胫骨和股骨。大多数变化是骨髓水肿的弥漫性增加。在两名志愿者中，这些变化类似于应力性骨折。
负重改变应被列入MR图像上髓内信号强度增加（即骨髓水肿）的原因清单中。
