Abstract
INTRODUCTION: Horner syndrome (HS) is a rare neurological disorder arising from disruption of the oculosympathetic pathway. Pediatric HS is uncommon and may be congenital, but underlying sinister causes need to be excluded. CASE PRESENTATION: An 18-week-old boy presented with right peri-orbital swelling, initially thought to be pre-septal cellulitis. Further ophthalmic review revealed a right-sided HS. Imaging identified a probable cervical neuroblastoma, leading to an urgent referral to oncology. CONCLUSION: Early recognition of pediatric HS is crucial as it may signal underlying malignancies like neuroblastoma. Atypical presentations with sequential or intermittent symptoms make diagnosis challenging. Comprehensive imaging and multidisciplinary care ensure timely diagnosis and management.