金属植入物对1.5T磁共振扫描热效应的安全性影响

摘要

目的 探讨金属植入物(钛合金和不锈钢)磁共振扫描热效应的安全性.方法 制作金属植入物实验标本在1.5T磁共振下进行产热实验,记录数据结果;监测实际带金属植入物磁共振检查患者40例并记录监测结果.结果 在磁共振检查前后实验标本上植入物附近局部组织温度均升高,钛合金组温度升高均值为(0.45±0.02)℃(t=13.0,P<0.01);不锈钢组温度升高均值为(0.75±0.04)℃(t=19.4,P<0.01).金属植入物处在磁共振检查射频波作用下能够产热,其中不锈钢组产热大于钛合金组(P<0.01).结论 实验表明植入物处在磁共振射频波作用下能够产热,但在实验标本上产热使邻近组织温度升高均<1.0℃.%Objective To investigate the security of thermal effects in MR (Magnetic Resonance) imaging of metal implants (titanium alloy and stainless steel).Methods The metal implant specimen was made to perform the heat production experiment with 1.5T MR imaging and record the relevant data. And 40 patients with metal implants were scanned by MRI to record relevant monitoring data.Results The temperature of local tissues surrounding the implants in the experimental specimen increased before and after MR examinations. The average increasing temperature in Titanium Alloy Group and Stainless Steel Group were (0.45±0.02)℃ (t=13,P<0.01) and (0.75±0.04)℃ (t=19.4,P<0.01). The metal implant was able to produce heat under the radio-frequency waves of MR imaging. Metal implants in Stainless Steel Group produced more heat than those in Titanium Alloy Group (P<0.01).Conclusion The experiment indicated that the implants could produce heat under the radio-frequency waves of MR imaging and the increasing temperature of the tissues surrounding the implant in the experimental specimen was less than 1.0℃.