Supplementary Material for: MRI-Induced Neurosensory Events in Decorative Black Tattoos: Study by Advanced Experimental Methods

Adverse reactions in tattooed skin during magnetic resonance imaging (MRI) are rare but well known. Previous reports describe sudden burning pain in tattooed skin, sometimes accompanied by mild erythema and oedema when entering MRI scanners. The pathophysiology remains unclear, but simple direct thermal heating can be excluded. It has been hypothesized that MRI-triggered torque and traction create neural sensations from magnetic pigment particles. However, this case enlightens yet another possible mechanism. We present a 35-year-old woman experiencing reoccurring stinging sensations in three decorative black tattoos just seconds after the initiation of the MRI. Single-blind tests with handheld power magnets or a dummy could reproduce painful subjective feelings in her tattooed skin. Similar events were provoked during re-evaluation with MRI. Surprisingly, chemical analyses and electron microscopy of skin samples revealed carbon black as the colouring agent – no iron-based solids were detected. Our case demonstrates that MRI tattoo reactions are not limited to magnetic contaminants alone. More distinct subgroups of MRI-induced reactions may occur. We hypothesize that radiofrequency induction of surface currents in black carbon particles adjacent to sensory axons in the dermis may lead to neurosensations.

在纹身皮肤进行磁共振成像（MRI）时发生的副作用极为罕见，然而却广为人知。既往报道中描述了纹身皮肤出现突发性灼烧疼痛，有时伴随轻微的充血和水肿，在进入MRI扫描仪时尤为明显。其病理生理机制尚不明确，但简单的直接热能加热可以排除。有假说认为，MRI触发的扭矩和牵引力可能从磁性颜料颗粒中产生神经感觉。然而，本案例揭示了另一种可能的机制。我们报道了一位35岁女性在MRI开始后几秒钟内，在其三个装饰性黑色纹身处反复出现刺痛感。使用手持强力磁铁或假体进行的单盲测试能够在她的纹身皮肤中重现疼痛的主观感受。在MRI复查期间也发生了类似事件。令人惊讶的是，皮肤样本的化学分析和电子显微镜检查发现，碳黑是着色剂——未检测到基于铁的固体。我们的案例表明，MRI纹身反应并非仅限于磁性污染物。可能存在更多明确的MRI诱导反应亚组。我们假设，射频在真皮中靠近感觉神经轴的黑色碳粒表面感应产生的电流可能导致神经感觉。