Qiu H H, Hedlund L W, Neuman M R, Edwards C R, Black R D, Cofer G P, Johnson G A
Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
IEEE Trans Biomed Eng. 1998 Jul;45(7):921-7. doi: 10.1109/10.686800.
We used in vivo magnetic resonance (MR) microscopy to follow the growth of fibrous capsule as a foreign body reaction to silicone implants in rats. Anesthetized rats were imaged 1, 7, 14, and 28 days after silicone-coated MR imaging coils were sutured to their neck muscles. On the twenty-eighth day, rats were sacrificed and coils and adjacent tissues were removed en bloc and fixed in formalin, reimaged with MR, and sectioned for conventional histology. Three-dimensional (3-D) spin-echo [3DFT] acquisition gave in-plane resolution of 32 x 32 microns in vivo and 16 x 16 microns ex vivo. All MR images showed a diffuse band of elevated signal intensity between the silicone of the coil and adjacent tissue. The border of the hyperintense band was thin and not well defined at seven days post-implantation. From 7-28 days, the band showed relatively homogeneous signal intensity and its thickness increased 44% on the rectus muscle side and 78% on the subcutaneous side. The capsule thickness determined either by MR in vivo and ex vivo microscopy or conventional histology was not significantly different, and there was a significant correlation between thickness measurements among those methods. MR in vivo microscopy provides sufficient resolution and spatial information to serially evaluate the growth of the foreign body fibrous capsule over time, thus achieving greater accuracy and consistency in measurements.
我们使用体内磁共振（MR）显微镜来追踪纤维囊的生长情况，该纤维囊是大鼠对硅酮植入物的异物反应。将涂有硅酮的MR成像线圈缝合到麻醉大鼠的颈部肌肉后，分别在第1、7、14和28天对大鼠进行成像。在第28天，处死大鼠，将线圈和相邻组织整块取出并固定在福尔马林中，再次进行MR成像，然后切片进行常规组织学检查。三维（3-D）自旋回波[3DFT]采集在体内的平面分辨率为32×32微米，体外为16×16微米。所有MR图像均显示线圈硅酮与相邻组织之间有一条信号强度升高的弥漫带。植入后7天时，高信号带的边界较薄且不清晰。从7天到28天，该带显示出相对均匀的信号强度，其厚度在直肌侧增加了44%，在皮下侧增加了78%。通过体内和体外MR显微镜或常规组织学测定的囊厚度无显著差异，且这些方法之间的厚度测量存在显著相关性。体内MR显微镜提供了足够的分辨率和空间信息，能够随时间连续评估异物纤维囊的生长情况，从而在测量中实现更高的准确性和一致性。
