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

Abstract

<h3>SUMMARY:</h3> Pathogenic variants in the <i>polymerase γ gene</i> (<i>POLG</i>) cause a diverse group of pathologies known as <i>POLG</i>-related disorders. In this report, we describe brain MR imaging findings and electroencephalogram correlates of 13 children with <i>POLG</i>-related disorders at diagnosis and follow-up. At diagnosis, all patients had seizures and 12 had abnormal MR imaging findings. The most common imaging findings were unilateral or bilateral perirolandic (54%) and unilateral or bilateral thalamic signal changes (77%). Association of epilepsia partialis continua with perirolandic and thalamic signal changes was present in 86% and 70% of the patients, respectively. The occipital lobe was affected in 2 patients. On follow-up, 92% of the patients had disease progression or fatal outcome. Rapid volume loss was seen in 77% of the patients. The occipital lobe (61%) and thalamus (61%) were the most affected brain regions. Perirolandic signal changes and seizures may represent a brain imaging biomarker of early-onset pediatric <i>POLG</i>-related disorders.