Clinic for Nuclear Medicine, University of Duisburg/Essen, Germany.
Clin Imaging. 2010 Jul-Aug;34(4):293-7. doi: 10.1016/j.clinimag.2009.06.025.
Nuclear magnetic resonance imaging has become a standard diagnostic procedure in clinical medicine and is well known to have hazards for patients with pacemaker or metallic foreign bodies. Compared to CT, the frequency of MRI examinations is increasing due to the missing exposure of the patients by X-rays. Furthermore, high-field magnetic resonance tomograph (MRT) with 3 T has entered clinical practice, and 7-T systems are installed in multiple scientific institutions. On the other hand, the possibility of burn injuries has been reported only in very few cases. Based on a clinical finding of a burn injury in a 31-year-old male patient during a routine MRI of the lumbar spine with standard protocol, the MR scanner was checked and the examination was simulated in an animal model. The patient received a third-degree burn injury of the skin of the right hand and pelvis in a small region of skin contact. The subsequent control of the MRI scanner indicated no abnormal values for radiofrequency (RF) and power. In the subsequent animal experiment, comparable injuries could only be obtained by high RF power in a microwave stove. It is concluded that 'tissue loops' resulting from a contact between hand and pelvis must be avoided. With regard to forensic aspects, the need to inform patients of such a minimal risk can be avoided if the patients are adequately positioned using an isolating material between the hands and pelvis. These facts must be emphasized more in the future, if high-field MRI with stronger RF gradients is available in routine imaging.
磁共振成像是临床医学中的标准诊断程序，众所周知，它对带有起搏器或金属异物的患者有危害。与 CT 相比，由于 MRI 检查不会使患者受到 X 射线照射，因此其检查频率正在增加。此外，具有 3T 的高场磁共振断层扫描仪（MRT）已进入临床实践，并且在多个科学机构中安装了 7T 系统。另一方面，仅在极少数情况下报告了烧伤的可能性。基于一名 31 岁男性患者在常规腰椎磁共振成像（标准方案）期间手部和骨盆出现烧伤损伤的临床发现，对磁共振扫描仪进行了检查，并在动物模型中模拟了检查。患者右手和骨盆的一小部分皮肤接触区域出现三度烧伤。随后对磁共振扫描仪的控制表明射频（RF）和功率没有异常值。在随后的动物实验中，只有在微波炉中使用高 RF 功率才能获得类似的损伤。因此得出结论，必须避免手部和骨盆接触产生的“组织环路”。就法医方面而言，如果在手部和骨盆之间使用隔离材料使患者充分定位，则可以避免告知患者这种最小风险。如果在常规成像中使用具有更强 RF 梯度的高场 MRI，则必须在将来更加强调这些事实。
