Fukuyama congenital muscular dystrophy MRI

Clinically: Floppy infant / hypotonia.

MRI findings:

Bilateral frontal Polymicrogyria.

Diffuse cerebral cortical atrophy marked in bilateral frontal and temporal lobes.

Bilateral temporo occipital white matter show patchy T2 hyper intensity suggestive of associated dysmyelination, bilateral hippocampal Mal orientation, ex vacuo dilatation of temporal horns of lateral ventricles.

Associated hypoplasia of corpus callosum.

Poorly pneumatised of paranasal sinuses and mastoid air cells.

Micro crania, brachycephaly, small posterior fossa.

Brainstem atrophy, mid line cleft on ventral aspect of Pons.

No associated cerebellar dysplasia. Ill-defined mid line vermis.

Impression:

Imaging diagnosis: Fukuyama congenital muscular dystrophy more likely than Walker Warburg syndrome as there is no associated cerebellar dysplasia.

Fukuyama congenital muscular dystrophy

Named after Yukio Fukuyama (1928-2014), a Japanese pediatric neurologist, who first described the condition in his 1960.

Exclusively found in Japan with an incidence of 2/4 per 100,000 infants and is the second most common muscular dystrophy after Duchenne muscular dystrophy.
Affected infants are hypotonic, generalised symmetric weakness affecting extremities and facial muscles by 1 year.
Accompanied by developmental delay and intellectual disability afterwards with epilepsy.

An autosomal recessive inherited disease due to a mutation in the fukutin-related protein (FKTN) gene.

Classic MRI brain features are polymicrogyria typically in the frontal and parietal lobes.Pachygyria in approximately half of patients, typically involving the temporal and occipital lobes.
Cerebellar polymicrogyria is seen in approximately 90% of patients. White matter changes patchy, spotty suggestive of dysmyelination.
Walker-Warburg syndrome is one of its main differentials, in which cerebellar dysplasia is commonly seen is not very common in Fukuyama congenital muscular dystrophy

Definitive treatment not available.