Radiological Diagnosis

Schizencephaly

[Figure - 1]-axial CT section shows large bilateral open lip schizencephaly clefts extending from the ventricle to the surface of the brain. These clefts are lined by gray matter (pathognomic for schizencephaly). [Figure - 2]- higher axial section gray matter lining of the clefts is well appreciated. These clefts are bilaterally symmetric.

Schizencephaly is one of the migrational disorders of brain, which include lissencephaly, pachygyria, heterotopia and polymicrogyria.it is characterized by a gray matter lined cleft that extends from the ependymal surface of the brain through the white matter to the pia.[1]

Two types are recognized: type I or closed lip schizencephaly, in which the cleft walls are in apposition and type II or open lip schizencephaly, in which the walls are separated. In either instance the cleft is lined by heterotopic gray matter. The clefts can be unilateral or bilateral, symmetric or asymmetric.[2]

Bilateral clefts have a worse prognosis for development, with seizures present in the majority. Patients may present with hemiparesis (more likely in unilateral forms) or tetraparesis (more likely in bilateral forms). Mental retardation and seizures are other common presentations, being more severe in bilateral clefts.[3]

CT scans of closed lip schizencephaly may show only a slight outpouching or "nipple" at the ependymal surface of the cleft. The full thickness cleft or the pial-ependymal seam may be difficult to detect on CT scans. Open lip schizencephaly has a larger, more apparent gray matter lined CSF cleft. The majority of patients have bilateral clefts, most of them roughly symmetrical in location and more likely open (type II) than closed (type I) the presence of heterotopic gray matter is considered pathognomic for schizencephaly, distinguishing it from an acquired condition. [4]

Present case highlights the CT findings in Schizencephaly. Schizencephaly was earlier considered a rare anomaly but now with advent of axial imaging (CT and MRI) this condition is more frequently recognized.