Paediatric idiopathic syringomyelia - a follow-up of radiological and clinical outcomes into adulthood.

Objective: Idiopathic syringomyelia (IS) is defined by the presence of a spinal syrinx without identifiable primary pathology. The natural history, clinical implications, and radiological management of IS in the paediatric patient remain poorly understood, with existing literature providing limited long-term data. This study aims to evaluate the long-term clinical and radiological outcomes of paediatric patients with IS, focusing on understanding predictive factors of clinical or radiological progression, and the correlation between clinical and radiological evolution.

Methods: This retrospective study included 28 paediatric patients diagnosed with IS, all with a minimum of three years of radiological follow-up. Cases of secondary syrinx caused by upstream pathology were excluded. Clinical and imaging data were analysed to assess the radiological change of the syrinx and change in symptoms. Correlations between radiological and clinical features were explored.

Results: The median radiological and clinical follow-up durations were 6.84 years and 7.66 years, respectively. A reduction in syrinx size (≥ 1 mm in width or anterior-posterior diameter) was observed in 53.6% of patients, with no significant association with gender, age at diagnosis, initial syrinx size, or scoliosis. Back pain occurred in 25% of patients; other modes of presentation include urological disturbance and neurological deficits. All patients remained clinically asymptomatic, stable or improved during follow-up. Radiological changes did not correlate with clinical outcomes. No predictors were found for radiological or clinical outcomes.

Conclusions: IS in paediatric patients follow a predominantly benign course, with radiological changes showing little clinical relevance. Repeated interval imaging appears unnecessary in stable cases, and management should prioritise clinical symptoms. This study provides the largest long-term dataset to date, supporting a conservative approach to IS management.