Presentation
Headaches.
Patient Data
Well-delineated lobulated cystic mass centered on the interpeduncular cistern of low signal on T1, heterogeneous/dirty signal on FLAIR and high signal on T2 with restricted diffusion and no enhancement on the postcontrast sequence. It shows a multidirectional extension:
downwards filling the prepontine cistern encasing the basilar artery and posterior cerebral arteries and extending to the right cerebellopontine angle
upwards filling the third ventricle
anteriorly filling the suprasellar cistern and encasing the pituitary stalk and optic chiasma
laterally displacing the cisternal portion of the trigeminal nerves
posteriorly mild extension to the ambient cistern
Case Discussion
Case showing the classic MRI features of an epidermoid cyst of the posterior cranial fossa with multidirectional extension.
DWI is important to differentiate an epidermoid cyst from an arachnoid cyst.
Unable to process the form. Check for errors and try again.