Neuroimaging Findings in Three Patients with Juvenile Huntington's Disease.

Huntington's disease (HD) is a rare, autosomal dominant neurodegenerative disorder marked by progressive motor, cognitive, and behavioral symptoms. Although most cases present in adulthood, approximately 1-15% occur before age 20, termed juvenile Huntington's disease (JHD). JHD often follows a more rapid and variable clinical course, with diverse presentations and unique radiological findings. It's rarity and heterogeneous clinical course make diagnostic and management challenges. This case series highlights the clinical and neuroimaging features of three genetically confirmed pediatric patients with JHD from the same family. Ages of symptom onset ranged from 6 to 12 years, with all patients showing expanded CAG repeats (71-83) in the HTT gene. While all presented with cognitive impairment and motor symptoms, their clinical presentations varied. One patient had prominent dystonia and agitation, while another developed significant bradykinesia and altered mental status. Brain MRI findings were consistent across cases, demonstrating severe bilateral caudate and lentiform nuclei atrophy with corresponding T2/FLAIR hyperintensities and T1 hypo intensities. Susceptibility-weighted imaging revealed focal mineral deposition in the globus pallidus in two patients. Notably, mild thoracic spinal cord thinning was observed in one patient, suggesting potential spinal involvement. This case series provides new insight into the phenotypic variability and also demonstrates the less commonly described imaging observations of JHD, including spinal cord changes and SWI abnormalities. It underscores the importance of early imaging, genetic testing, and multidisciplinary care. Support for affected families is critical, as JHD imposes profound emotional and caregiving burdens.