A 2.3 x 2.7 x 2cm ovoid lesion in the left ventricular trigone has a thin smooth nonenhancing wall, with internal signal non diffusion restricting and following CSF. No flow voids or suspicious vascularity. No surrounding signal abnormality. No MRI findings suspicious for calcification. Slight mass effect, with enlargement of the left lateral ventricular body, occipital and temporal horns, with displacement of choroid. However, midline is maintained, and no sulcal effacement is present. No second lesion identified.