FIG 1. Brain MR imaging in a 44-year-old man.

A, Axial T1-weighted MR image (672/14 [TR/TE]) depicts a hypointense multicystic mass lesion (arrow) in the left temporal horn; the temporal horn is trapped. Periventricular white matter is also hypointense, and the right medial temporal lobe shows a single rounded lesion (arrowhead) with similar features.

B, Axial T2-weighted (5500/90) image depicts the mass lesion (arrow) in the temporal lobe, periventricular white matter, and the single rounded lesion (arrowhead) in the right medial temporal lobe as hyperintense.

C, Axial T1-weighted (672/14) image reveals an enhancing mass in the region of the foramen of Monro (arrowheads), extending bilaterally into the frontal horns. Choroid plexuses are enlarged and enhanced (arrow).

D, Coronal T1-weighted (672/14) image shows enhancement of the meninges (arrow).

E, Axial fluid-attenuated inversion recovery (9000/119) image reveals dilated hyperintense Virchow-Robin spaces (arrow) in the basal ganglia.