History: 10-month-old girl with midline facial abnormalities and a mass in the nasopharynx
Findings: Axial and coronal CT images with bone and soft tissue reconstruction, receptively show cerebrospinal fluid
attenuation mass extending into the nasopharynx that is directly contiguous with the third ventricle. A wide defect is present
in the basisphenoid, and there is separation and angulation of the lateral ventricles producing a “Viking horn’ appearance, indicating agenesis of
the corpus callosum. A sagittal MR image also reveals the cerebrospinal fluid-filled mass and shows to better advantage the lack of brain tissue within it.