Presentation
Increased head circumference
Patient Data
There are two large extra-axial cysts of CSF signal, filling the whole middle cranial fossae, extending to the insular regions, and displacing the temporal, and frontal lobes with no significant mass effect on the midline structures. No restricted diffusion is seen on DWI/ADC.
The cortex appears relatively thickened (mainly at frontal lobes) with few board gyri, shallow sulci with relatively smooth border between gray, and white matter, indicating most likely pachygyria. Moderate dilatation of the ventricular system with no stenosis seen at the Aqueduct of Sylvius on sagittal Fiesta sequence.
Mega cisterna magna is noted (normal variant).
Case Discussion
MRI features of bilateral temporal arachnoid cysts type III according to Galassi classification of middle cranial fossa arachnoid cysts with associated pachygyria