Identification of brain malformations: neuropathological approach

Area of Science:

• Neuroscience
• Developmental Biology
• Pathology

Background:

• Prenatal imaging advances (ultrasound, MRI) highlight the need for detailed fetal neuropathology.
• Brain malformations were historically viewed as developmental accidents, but neuropathology reveals specific phenotypes.
• Clinical and radiological documentation is insufficient; neuropathological study is essential for diagnosis and cause analysis.

Purpose of the Study:

• To emphasize the importance of comprehensive neuropathological examination in fetal brain malformations.
• To explore the phenotypic uniqueness and causal heterogeneity of brain malformations.
• To highlight the role of molecular studies and signaling pathways in understanding malformation etiology.

Main Methods:

• Full autopsy and frozen tissue storage for DNA analysis after pregnancy termination or prenatal death.
• Limiting the delay between death and autopsy to mitigate rapid autolysis of brain tissue.
• Multidisciplinary evaluation including fetal, maternal, and placental pathology.

Main Results:

• Each brain malformation is phenotypically unique and causally heterogeneous.
• Mutations in different genes within a signaling pathway can cause similar malformations.
• Signaling pathways are potential targets for toxic agents mimicking genetic causes.

Conclusions:

• A multidisciplinary approach to fetal brain malformations, incorporating neuropathology and molecular analysis, is vital.
• Gene identification through this approach is crucial for genetic counseling and early prenatal molecular diagnosis (10-12 weeks gestation).
• Understanding early nervous system patterning and molecular pathways is increasingly important for evaluating brain malformations.