Presentation
Enlarged head size
Patient Data
Large midline cystic lesion splays both hemispheres. The septum pellucidum and interhemispheric fissure are not seen. Both frontal and temporal lobes are well-formed, with no abnormal thalamic fusion. Both frontal horns, right temporal horn and right lateral ventricle are well seen. Splaying of the skull sutures and fontanels.
Case Discussion
The Barkovich classification of interhemispheric cysts associated with corpus callosum agenesis includes type 1 cysts, which are outpouching communicates with the lateral or third ventricles, and type 2 cysts, which are loculated and don't communicate with the ventricular system.
In our case, there is evidence of the cyst being communicating with the left lateral ventricle as well as the third ventricle, findings that suggest type 1 interhemispheric cyst.