The Perirolandic Sign: A Unique Imaging Finding Observed in Association with Polymerase γ-Related Disorders.

Area of Science:

• Neurology
• Genetics
• Pediatric Neurology

Background:

• Pathogenic variants in the polymerase gamma gene (POLG) are associated with a spectrum of neurological disorders.
• POLG-related disorders present with diverse clinical manifestations, impacting multiple organ systems.

Purpose of the Study:

• To characterize brain MR imaging findings and electroencephalogram (EEG) correlates in children diagnosed with POLG-related disorders.
• To identify potential neuroimaging biomarkers for early diagnosis and prognosis in pediatric POLG-related disorders.

Main Methods:

• Retrospective analysis of brain MR imaging and EEG data from 13 pediatric patients with POLG-related disorders at diagnosis and during follow-up.
• Correlation of neuroimaging findings with clinical presentation, including seizures and disease progression.

Main Results:

• At diagnosis, all patients experienced seizures, and 12/13 showed abnormal MR imaging. Common findings included thalamic (77%) and perirolandic (54%) signal changes.
• Epilepsia partialis continua was associated with perirolandic (86%) and thalamic (70%) signal changes.
• On follow-up, 92% exhibited disease progression or fatal outcomes, with significant volume loss (77%) and affection of the occipital lobe (61%) and thalamus (61%).

Conclusions:

• Perirolandic signal changes and seizures may serve as valuable neuroimaging biomarkers for early-onset pediatric POLG-related disorders.
• POLG-related disorders in children are characterized by progressive brain abnormalities, particularly affecting the thalamus and occipital lobes.