Bilateral frontoparietal polymicrogyria

A rare neurological disorder affecting brain development

Bilateral frontoparietal polymicrogyria
Synonyms	BFPP
Pronounce	/ˌbaɪ.ləˈlæt.ər.əl ˌfrʌn.toʊˌpær.iˈiː.təl ˌpɒl.i.maɪˈkɹoʊ.dʒaɪ.ri.ə/
Field	Neurology, Medical genetics
Symptoms	Developmental delay, intellectual disability, seizures, hypotonia, strabismus, cerebellar ataxia
Complications	Epilepsy, motor and cognitive impairments
Onset	Infancy or early childhood
Duration	Lifelong
Types	Genetic cortical malformation
Causes	Mutations in the GPR56 gene (autosomal recessive inheritance)
Risks	Family history, consanguinity
Diagnosis	MRI imaging, genetic testing
Differential diagnosis	Other forms of polymicrogyria, lissencephaly, cerebral palsy
Prevention	Genetic counseling for at-risk families
Treatment	Supportive care, physical and speech therapy, seizure control
Medication	Antiepileptic drugs for seizures
Prognosis	Varies; developmental and neurological outcomes differ by severity
Frequency	Very rare
Deaths	Depends on severity; not typically fatal

Lissencephaly:Brain MRI, T1 weighted, transverse plane, that shows lyssencephaly, manifested as scarce and wide circumvolutions, mostly in the occipital, parietal and temporal lobes. As aggregated findings, there is ventriculomegaly, no true Sylvian cissure, too thick gray matter and ectopic gray matter in the white matter.

GPCR classification

Bilateral frontoparietal polymicrogyria (BFPP) is a rare neurological disorder characterized by abnormal development of the cerebral cortex, specifically affecting the frontal and parietal lobes of the brain. This condition is a form of polymicrogyria, which involves the presence of an excessive number of small, irregularly formed gyri on the surface of the brain.

Pathophysiology

Polymicrogyria results from abnormal neuronal migration during embryonic development, leading to the formation of multiple small gyri. In BFPP, this malformation is bilateral and predominantly affects the frontoparietal regions. The abnormal cortical development can disrupt normal brain function, leading to a variety of neurological symptoms.

Genetics

BFPP is often associated with mutations in the GPR56 gene, which plays a crucial role in brain development. This gene provides instructions for making a protein involved in the regulation of cell adhesion and cell signaling, processes essential for the proper formation of the cerebral cortex. The condition is typically inherited in an autosomal recessive pattern, meaning that both copies of the gene in each cell have mutations.

Clinical Features

Individuals with BFPP may present with a range of neurological symptoms, including:

• Developmental delay
• Intellectual disability
• Seizures
• Spasticity
• Hypotonia
• Cerebellar ataxia

The severity of symptoms can vary widely among affected individuals, even within the same family.

Diagnosis

The diagnosis of BFPP is typically made through a combination of clinical evaluation, neuroimaging, and genetic testing. Magnetic resonance imaging (MRI) of the brain is used to identify the characteristic pattern of polymicrogyria in the frontoparietal regions. Genetic testing can confirm mutations in the GPR56 gene.

Management

There is currently no cure for BFPP, and treatment is primarily supportive and symptomatic. Management strategies may include:

• Anticonvulsant medications to control seizures
• Physical therapy to improve motor function
• Occupational therapy to enhance daily living skills
• Speech therapy to address communication difficulties

Prognosis

The prognosis for individuals with BFPP varies depending on the severity of the condition and the presence of associated complications. Early intervention and supportive therapies can improve quality of life and functional outcomes.

Related pages

• Polymicrogyria
• Cerebral cortex
• Neurological disorder
• Genetic disorder

External links

• Bilateral Frontalparietal Polymicrogyria at NIH's Office of Rare Diseases