Arachnoid Cysts In A Paediatric Population - Presentation And Outcome

Introduction Arachnoid cysts are the most common type of brain cysts, reported in 1% of the population, with a male predominance. The likely cause is a split of the arachnoid membrane. The majority are thought to be asymptomatic (80%) and stable but can present with symptoms of raised intracranial pressure, sometimes secondary to trauma. Objectives We sought to determine the prevalence of arachnoid cysts in a paediatric population, presenting symptoms, if any, location of cyst, complications, management and outcome. Methods We did a retrospective review of our radiology database to ascertain cases of arachnoid cysts diagnosed antenatally or postnatally by ultrasound, computed tomography or magnetic resonance imaging in Cork University Hospital over a 3-year period (2014–2017) followed by review of their clinical notes. Outcome was classified as improved (cyst reduction in size or complete resolution), unchanged (no clinical worsening, cysts unchanged in size) and worse (clinical deterioration or radiological progression of cyst). Results There were 62 cases diagnosed in the above time period: 16 10 years old. There were 2 antenatally diagnosed, both in the last trimester of pregnancy. There was a male predominance occurring in 58% (36/62). Indications for neuroimaging included seizures (17), developmental delay (15), headaches (11), head injuries (5) and miscellaneous (14) which included psychiatric symptoms, precocious puberty and neurocutaneous syndromes. One of the neonates underwent endoscopic fenestration of the arachnoid cyst in the second month of life with additional need for cystoperitoneal shunt at 7 months old. Surgery was performed in 6 cases (10%), while 56 (90%) were conservatively managed with frequent clinical and imaging monitoring. Seven cases had surgical intervention which included endoscopic fenestration in 5/7 cases (71%), craniotomy and evacuation in 2/7 cases (28%). Two of the 5 cases who had endoscopic fenestration also required shunting. Surgery of symptomatic cases provided overall good results. Conclusions The majority of arachnoid cysts in our study, remained stable and didn’t require surgical intervention. Surgical treatment of intracranial arachnoid cysts remains controversial owing to limited understanding of its natural history and physiology. Current literature favours endoscopic interventions for complicated arachnoid cysts.