Kennedy Krieger Institute, Baltimore, Maryland; Johns Hopkins University, Baltimore, Maryland.
Children's Hospital Los Angeles, Los Angeles, California.
Pediatr Neurol. 2023 Dec;149:56-62. doi: 10.1016/j.pediatrneurol.2023.08.021. Epub 2023 Aug 19.
Acute flaccid myelitis (AFM) presents with acute onset of flaccid paralysis with involvement of the gray matter on magnetic resonance imaging (MRI) of the spinal cord. Studies have reported brain MRI abnormalities, but the characteristics have not been fully defined. In this multicenter study, we assessed the acute features and evolution of brain MRI abnormalities in AFM.
We reviewed brain MRIs of patients with AFM who presented to four referral hospitals between 2012 and 2018. Cases met established criteria for AFM. We analyzed the initial and follow-up brain MRIs. Areas were divided into supratentorial, infratentorial, and subdivisions within those regions.
A total of 66 patients were included. Brain MRI abnormalities were present in 34 (52%). Infratentorial abnormalities were more common, occurring in 33 (97%) cases with the dorsal pons being the most frequently affected area (88%). Abnormalities were also present in the medulla (74%), cerebellum (41%), and midbrain (38%). Nine subjects (26%) exhibited both supratentorial and infratentorial abnormalities, whereas isolated supratentorial changes were present in only one (3%). Contrast-enhancing abnormalities were encountered in 9% of cases and meningeal involvement in 6%. On follow-up, most abnormalities, 20 of 24 (83%), were stable, improving, or had resolved.
Brain MRI abnormalities occur in about half of the cases of AFM and commonly resolve with time. Dorsal pontine involvement is a characteristic MRI feature, whereas isolated supratentorial abnormalities are rare. Clinicians should consider that brain imaging abnormalities do not exclude a diagnosis of AFM in patients with typical presentations.
急性弛缓性脊髓炎（AFM）表现为急性弛缓性瘫痪，伴脊髓磁共振成像（MRI）上灰质受累。有研究报道脑 MRI 异常，但特征尚未完全明确。在这项多中心研究中，我们评估了 AFM 患者脑 MRI 的急性特征和演变。
我们回顾了 2012 年至 2018 年间 4 家转诊医院就诊的 AFM 患者的脑 MRI。病例符合 AFM 的既定标准。我们分析了初始和随访脑 MRI。将区域分为幕上、幕下及这些区域的细分。
共纳入 66 例患者。34 例（52%）存在脑 MRI 异常。幕下异常更常见，33 例（97%）存在异常，其中背侧脑桥最常受累（88%）。异常也存在于延髓（74%）、小脑（41%）和中脑（38%）。9 例（26%）存在幕上和幕下异常，而仅有 1 例（3%）存在孤立性幕上改变。9%的病例存在对比增强异常，6%的病例存在脑膜受累。随访时，24 例中的 20 例（83%）异常稳定、改善或已解决。
约一半的 AFM 病例存在脑 MRI 异常，且随着时间推移通常会缓解。背侧脑桥受累是 MRI 的一个特征性表现，而孤立性幕上异常罕见。对于表现典型的患者，脑影像学异常并不能排除 AFM 的诊断。
