Intracranial Arachnoid Cyst in Children: Clinical Presentation and Risk Factors for Surgical Intervention.

Introduction: Intracranial arachnoid cysts (IAC) in children are a common incidental finding on imaging. Most IACs are asymptomatic and can be monitored; however, a small percentage may enlarge and require surgical intervention. This study aimed to identify clinical risk factors in patients with IAC who underwent surgery versus those who did not.

Methods: We conducted a retrospective chart review from 2009 to 2021 at a free-standing children's hospital. A total of 230 patients diagnosed with an IAC aged 0-21 years of age were included in the study. Data on demographics, imaging, and neurological follow-up were analyzed.

Results: Out of 230 patients, 45 (19.6%) underwent surgery. At time of IAC diagnosis, the surgical patients were younger (median age 1.1 years), and their median cyst volume was larger (41.7 cm3), compared to nonsurgical patients (median age 5.9 years, volume 11.8 cm3, respectively). Headache was the most common reason for initial imaging in nonsurgical patients (54/185, 29.2%) while prenatal ultrasound (11/45, 24.4%) and macrocephaly (11/45, 24.4%) were the most common reasons for surgical patients. The majority of both surgical and nonsurgical patients had the IAC incidentally found (41/45, 91.1% and 181/185, 97.8%, respectively). Surgery relieved symptoms in 38/45 (84.4%) patients. Cyst volume and age were predictors of increased odds of having surgery.

Discussion/conclusion: Patients who underwent surgery were younger and had larger cyst volumes at time of diagnosis. The majority of the IAC were found incidentally and remained stable over prolonged follow-up. The majority of the patients experienced relief of symptoms postsurgical intervention. There is a greater odds of having surgical treatment with decreased age and greater cyst volume at diagnosis, and therefore these patients should be monitored closely for development of symptoms indicating need for surgical intervention.