Garrido L, Kwong K K, Pfleiderer B, Crawley A P, Hulka C A, Whitman G L, Kopans D B
NMR Center Massachusetts General Hospital, Charlestown.
Magn Reson Imaging. 1993;11(5):625-34. doi: 10.1016/0730-725x(93)90004-w.
We have developed an echo-planar (EP) proton chemical shift imaging (CSI) MR technique that allow us to discriminate the polydimethylsiloxane (PDMS, silicone) proton MR signal from that of the fat and water protons found in tissues, in order to map the distribution of PDMA in humans who have silicone gel prostheses. Silicone gel-filled prosthetic implants induce histologic changes in the surrounding tissue which are attributed to the leakage of free PDMS from the prosthesis. The T2 relaxation measurements of three silicone gels show that there are two components in them, each with a different degree of molecular mobility. The presence of free silicone is confirmed by chloroform extraction, which removed 14-28% of the material. This free polymer present in the gel can pass through the intact or ruptured membrane of the implant into the surrounding tissue. Our preliminary imaging results indicate that EP-CSI MR might be useful as a diagnostic technique for implant malfunction.
我们开发了一种回波平面（EP）质子化学位移成像（CSI）磁共振技术，该技术使我们能够区分聚二甲基硅氧烷（PDMS，硅酮）的质子磁共振信号与组织中脂肪和水质子的信号，以便绘制植入硅胶假体的人体内PDMA的分布情况。填充硅胶的假体植入物会在周围组织中引起组织学变化，这归因于游离PDMS从假体中泄漏。对三种硅胶的T2弛豫测量表明，它们中有两个成分，每个成分具有不同程度的分子流动性。通过氯仿萃取证实了游离硅酮的存在，氯仿萃取去除了14-28%的物质。凝胶中存在的这种游离聚合物可以通过植入物完整或破裂的膜进入周围组织。我们的初步成像结果表明，EP-CSI磁共振可能作为一种诊断植入物故障的技术有用。
