Bilateral wallerian degeneration of the middle cerebellar peduncles secondary to pontine infarction: A case series.

Objective: Wallerian degeneration (WD) of middle cerebellar peduncles (MCPs) secondary to pontine infarction is rarely reported in the literature. Our aim in this study is to characterize its clinical and neuroradiological features.

Methods: A retrospective review of 7 patients from a single institution was conducted. Only patients with pontine infarction and subsequent degeneration of the MCPs were included in the analysis. The features of clinical presentation and neuroimaging finding were summarized by our experienced neurologists.

Results: Seven patients (5 male, 2 female), ranging in age from 50 to 77 years, satisfied the inclusion criteria. All patients had cardiovascular risk factors and hypertension was the most common one. Almost all of the patients had hemiparesis and dysarthria, and could achieved good clinical outcome. On the initial scan, hyperintense on T2- and diffusion-weighted images suggested the acute pontine infarction. On the follow-up scan, however, hyperintensities of bilateral MCPs on T2-weight and FLAIR images were apparently demonstrated in all patients. The specific lesions in the MCPs were attributed to bilateral WD of the pontocerebellar fibres secondary to pontine infarction.

Conclusion: WD should be taken into account when patients are initially diagnosed with paramedian pontine infarction and follow-up MRI manifest as symmetrical hyperintense in the MCPs.