Ponto-medullary Junction Infarction Presenting as Ipsilateral Abducens Nerve Palsy and Contralateral Hemiparesis without Facial Involvement

Abstract

Raymond syndrome is a pontine syndrome consisting of ipsilateral abducens nerve palsy, contralateral facial paralysis, and contralateral hemiparesis. However, subsequent clinical observations argued on the presentation of facial involvement. The only differentiating point between the facial including called classic type and the facial sparing Raymond syndrome is the location of the lesion. The classic type involves abducens nerve, corticofacial, and corticospinal tracts; while in the facial sparing type, corticofacial tracts, and peripheral facial nerves are spared. We experienced a 78-year-old man presented with sudden onset dizziness, binocular horizontal diplopia, and right-sided motor weakness. Neurological examination showed he had left abducens nerve palsy and right hemiparesis without facial involvement. Brain magnetic resonance imaging showed acute ischemic infarction in the left ponto-medullary junction. Regardless of the presence or absence of facial palsy, the combination of abducence nerve palsy and contralateral hemiparesis should direct the clinician’s attention towards the medial ventral caudal ponto-medullary junction. Keywords: Abducens nerve; Hemiparesis; Ponto-medullary junction; Raymond syndrome 중심 단어: ì™¸ì „ì‹ ê²½, ë°˜ì‹ ë§ˆë¹„, 교뇌연수이음부, ë ˆì´ëª¬ë“œì¦í›„êµ°