Cerebellar cleft

Cerebellar clefts are rare congenital abnormalities of the posterior fossa, where cerebellar grey matter extends from the surface into the parenchyma, in some cases even reaching the fourth ventricle.

Clinical presentation

Language and speech disorders, cognitive impairment, truncal ataxia, ocular movement disorders, and behavioral disorders represent the most common symptoms .

Pathology

Cerebellar clefts are typically secondary changes most commonly caused by fetal cerebellar hemorrhages. Simultaneous, similar supratentorial abnormalities such as schizencephaly may be present, further underlining importance of the the in utero sustained injury .

Radiographic features

As with most congenital intracranial malformations, MRI is the imaging method of choice.

Typical findings are :

• cleft extending from the cerebellar surface into the parenchyma, which may reach the fourth ventricle
• irregularity of the cerebellar folia
• irregular gray and white matter junction
• white matter structural abnormalities adjacent to the cleft combined with a reduced volume of the affected hemicerebellum
• the cerebellar vermis is virtually always normal