Expanding the Distinctive Neuroimaging Phenotype of ACTA2 Mutations
F D'Arco1, C A Alves2, C Raybaud3
1From the Departments of Radiology (F.D'A., W.K.K.C.) darcofel@gmail.com.
AJNR. American Journal of Neuroradiology
|September 29, 2018
Summary
ACTA2 Arg179His mutations cause unique brain malformations, including corpus callosum abnormalities and pons flattening. These findings aid in diagnosing neurovascular conditions when cerebrovascular imaging is not performed.
Area of Science:
- Neurology
- Genetics
- Radiology
Background:
- ACTA2 Arg179His mutations are linked to a specific neurovascular condition.
- This condition presents with intracranial artery abnormalities, absent Moyamoya collaterals, and internal carotid artery issues.
Purpose of the Study:
- To describe unique brain malformative findings in patients with ACTA2 Arg179His mutations.
- To identify neuroimaging features that may suggest the diagnosis even without targeted cerebrovascular imaging.
Main Methods:
- Retrospective review of neuroimaging studies from 14 patients with ACTA2 mutations.
- Analysis of brain malformations and other abnormal brain MRI findings.
Main Results:
- 100% of patients showed anterior corpus callosum abnormalities and radial frontal gyration.
- 93% exhibited pons flattening and indentations; 85% had cerebral peduncle "squeezing".
Conclusions:
- The observed brain findings are likely deformations due to mechanical interaction with rigid arteries during development.
- These malformations can serve as diagnostic indicators for ACTA2-related disorders.
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