Cerebellar agenesis is a rare congenital abnormality which can result from failure to develop normal cerebellar tissue or destruction of normally developed tissue.
For a more general overview of cerebellar malformations, please refer to the article on classification systems for malformations of the cerebellum.
Typically small remnants of the cerebellum are present, including cerebellar peduncles and vermian lobules, and as such the term subtotal cerebellar agenesis is often used. Cerebellar agenesis or hypoplasia has previously been referred to as Chiari IV malformation, however this term is now considered obsolete 1, 2.
While one might expect these individuals to mainly show motor coordination difficulties, the plasticity of the brain is such that motor issues, although present, are not necessarily as severe as in patients with cerebellar lesions acquired after birth. Patients with cerebellar agenesis do however display varying degrees of cognitive impairment in memory, behavior, language and social functioning, and often autism or autism-like behavior is encountered.
- 1. Romina Romaniello. Cerebellar Agenesis. 1855-1872. doi:10.1007/978-94-007-1333-8_84
- 2. Choh NA, Choh SA. MRI demonstration of subtotal agenesis of the cerebellum with closed-lip schizencephaly. Ann Saudi Med. 2011;31 (2): 207-8. doi:10.4103/0256-4947.78212 - Free text at pubmed - Pubmed citation
- 3. Yu F, Jiang QJ, Sun XY et-al. A new case of complete primary cerebellar agenesis: clinical and imaging findings in a living patient. Brain. 2014;138 (6): e353. doi:10.1093/brain/awu239 - Pubmed citation