Isolated complete oculomotor nerve palsy as a presentation of adult medulloblastoma

Abstract

Figures

Magnetic resonance scan of the brain of the patient with medulloblastoma and cerebrospinal fluid dissemination. ( A ) Coronal and ( B ) Axial T1-weighted SE after gadolinium (Gd) shows thickening and contrast enhancement of the left oculomotor nerve (arrow). ( C ) Axial T1-weighted SE after Gd reveals a nodular lesion in the lower medial region of the right hemisphere of the cerebellum (arrow). ( D ) Axial DWI B1000 sequence shows restricted diffusion in the nodular lesion (arrow).

Full text

A 37-year-old man presented with isolated complete oculomotor nerve palsy, without other neurological signs. Magnetic resonance imaging (MRI) showed thickening and enhancement of the left third cranial nerve, along with a small nodular lesion in the right cerebellar hemisphere with diffusion restriction ( Figure 1 ). Repeated cerebrospinal fluid analysis eventually confirmed the presence of neoplastic cells. Resection of the cerebellar lesion revealed desmoplastic/nodular-type medulloblastoma (MB), sonic hedgehog (SHH)-activated, and TP53 wildtype. The patient was treated with neuroaxis radiotherapy and adjuvant chemotherapy. This case demonstrates a rare presentation of adult MB, highlighting the importance of considering leptomeningeal dissemination in the differential diagnosis of isolated cranial neuropathies. 1 2 3 4

Magnetic resonance scan of the brain of the patient with medulloblastoma and cerebrospinal fluid dissemination. ( A ) Coronal and ( B ) Axial T1-weighted SE after gadolinium (Gd) shows thickening and contrast enhancement of the left oculomotor nerve (arrow). ( C ) Axial T1-weighted SE after Gd reveals a nodular lesion in the lower medial region of the right hemisphere of the cerebellum (arrow). ( D ) Axial DWI B1000 sequence shows restricted diffusion in the nodular lesion (arrow).