MRI of a 6-year-old girl with drug-resistant focal seizures shows a full-thickness cleft in the left frontoparietal hemisphere extending from the pial surface to the lateral ventricle. The walls of the cleft are lined by grey matter, and polymicrogyria surrounds the cleft lips. The most likely diagnosis is:

• A Porencephaly
• B Hydranencephaly
• C Arachnoid cyst with porencephalic extension
• D Schizencephaly ✓

Explanation

Schizencephaly is a developmental malformation consisting of a grey matter lined cleft that spans the entire hemisphere from pia to ventricle, with heterotopic grey matter and polymicrogyria at the cleft lips. Porencephaly is an encephaloclastic (destructive) cavity, usually post-haemorrhagic or post-infectious, lined by white matter or gliotic tissue rather than grey matter, which is the single feature that separates it from schizencephaly on imaging.

Reference: Osborn's Brain: Imaging, Pathology, and Anatomy, 2nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.