Harlequin syndrome following microwave ablation in a child with a symptomatic paraspinal mass

Our goal is to describe a case of Harlequin syndrome associated with microwave ablation in the treatment of a symptomatic paraspinal mass in a child, along with a summary of the literature. Our patient is the only known case of persistent Harlequin syndrome associated with microwave ablation treatment of a symptomatic paraspinal mass. Harlequin syndrome is a rare neurological condition characterised by unilateral sweating and flushing of the face, neck and/or upper chest. The specific mechanism is unclear, but the majority of cases are believed to be a result of contralateral lesions along the sympathetic chain. CT-guided microwave ablation therapy is a minimally invasive technique used as an alternative to surgery in this case due to the risk and morbidity associated with excision of the mass. There is limited literature assessing the use and inherent risk of developing complications following microwave ablation to the paraspinal region in the paediatric population.