Isolated peripheral facial palsy (P-FP) can lead to lesions involving the inferomedial tegmentum of the pons. However, cases with P-FP in result of a medullary lesion have rarely been reported and result from a paraventricular lesion have never been reported before.
We described a 63-year-old man presenting with isolated P-FP due to ipsilateral pontomedullary infarction. Brain diffusion MRI revealed a hyper-intense signal on the left dorsolateral portion of the upper medulla and pontomedullary junction. And then we experienced a 77-year-old man presenting with lateral paraventricular infarction who showed contralateral peripheral type facial palsy. Brain diffusion-weighted image(DWI) showed a high-signal intensity lesion in the right lateral paraventricule and part of the posterior limb of the right internal capsule.
These two cases caution that a central nervous etiology should be considered in patients with P-FP, especially if they have high risk factors of cerebral infarction.