Kremmer S, Schiefer U, Wilhelm H, Zrenner E
Abt. Pathophysiologie des Sehens und Neuroophthalmologie, Universitäts-Augenklinik Tübingen.
Klin Monbl Augenheilkd. 1996 Mar;208(3):201-2. doi: 10.1055/s-2008-1035196.
A 49-year-old patient suffered from a binocular perforating trauma with metal foreign bodies in 1974. During an MRI examination in 1992 for a lumbar spine herniation a metal foreign body was mobilised from the deeper vitreal and retinal area, now causing optical disturbances freely floating in the anterior vitreous. Refusing an operation, the patient, an electrical engineer, tried himself to remove the foreign body out of the optical axis by exposing his head to the electro-magnetic field of an induction coil (pulsed magnetic induction B at t0 of 0.26 Tesla). The foreign body was split into multiple small parts no longer disturbing the patient. To early detect a siderosis regular ophthalmological controls including ERG are necessary. This example stresses that even small intraocular metal foreign bodies are a contraindication for the usually applied field strength of MRI examinations.
一名49岁患者在1974年遭受双眼穿孔伤并伴有金属异物。1992年,该患者因腰椎间盘突出症接受磁共振成像(MRI)检查时,一个金属异物从更深的玻璃体和视网膜区域移动到前玻璃体中自由漂浮,导致了视觉障碍。作为一名电气工程师,该患者拒绝手术,试图通过将头部暴露在感应线圈的电磁场(t0时刻脉冲磁感应强度B为0.26特斯拉)中来将异物移出光轴。异物被分裂成多个小碎片,不再对患者造成干扰。为了早期发现铁质沉着症,需要进行包括视网膜电图(ERG)在内的定期眼科检查。这个例子强调,即使是眼内小的金属异物也是通常应用的MRI检查场强的禁忌证。