Radiation treatment is widely used to address unresectable intracranial tumors. Owing to the nature of therapy, healthy tissue and diseased regions will be affected. New insights have shown that not only does this impact brain parenchyma but it causes changes in fluid status, myelination, and the integrity of the blood-brain barrier. This alters how peripheral and central immune systems interact, perpetuating neuroinflammation. Rare case reports in the adult literature have described multifocal, multiphasic demyelinating lesions after radiation. Here we describe 2 pediatric cases of relapsing demyelination after and in conjunction with radiation therapy for ependymoma, consistent with a multiple sclerosis phenotype. Insights into the underpinnings of multiple sclerosis show peripheral inflammation, blood-brain barrier disruption, and antigenic mimicry stimulate neuroinflammation. Here we investigate the roll that radiation, tumor burden, and systemic inflammation may play in creating demyelinating disorders. We strive to elucidate common pathophysiology between radiation-induced brain injury and multiple sclerosis.

放射治疗广泛用于治疗无法切除的颅内肿瘤。由于治疗的性质，健康组织和患病区域会受到影响。新的见解表明，这不仅会影响脑实质，还会导致体液状态、髓鞘形成和血脑屏障完整性的变化。这改变了外周和中枢免疫系统相互作用的方式，使神经炎症持续存在。成人文献中罕见的病例报告描述了放射后多灶性、多期脱髓鞘病变。在这里，我们描述了 2 例在室管膜瘤放疗后和联合放疗后复发性脱髓鞘的儿童病例，与多发性硬化表型一致。对多发性硬化症基础的洞察表明，外周炎症、血脑屏障破坏、和抗原模拟刺激神经炎症。在这里，我们研究了辐射、肿瘤负荷和全身炎症在产生脱髓鞘疾病中可能发挥的作用。我们努力阐明辐射诱发的脑损伤和多发性硬化症之间的共同病理生理学。