Figure 1: 18-year-old girl presenting with headache. (a) Sagittal T1- weighted and axial T1-weighted magnetic resonance imaging (MRI) scan (done on Siemens MAGNETOM Avanto 1.5 Tesla MRI Machine)) in a 18-year-old female demonstrating a small hyperintense lesion (yellow arrow) in left quadrigeminal cistern (*) abutting the dorsum of the tectal plate (ƒ¢). Normal corpus callosum (white arrow). (b) T2- weighted MRI image demonstrating hypointense lesion (yellow arrow) in left quadrigeminal cistern (*). (c) Gradient echo image demonstrating a "signal drop out" (yellow arrow) in the left quadrigeminal cistern. (d) Noncontrast axial computed tomography (CT) image demonstrating the same lesion in the left quadrigeminal cistern as a hypodensity (yellow arrow) having fat attenuation (CT value: −50−60 HU)