Factors influencing outcome in patients with colloid cysts who present with acute neurological deterioration

•Colloid cysts are associated with acute neurologic deterioration and sudden death.•Larger colloid cyst sizes were associated with higher mortality rates.•Females, even with smaller cyst sizes, are at greater risk of death than men.•Prompt surgical intervention in extremis led to survival in over half the patients. Colloid cysts have been associated with acute neurologic deterioration and sudden death. However, the low incidence of associated sudden deaths has meant that factors influencing outcome in patients who present with acute neurological deterioration have not been extensively published. A PubMed literature search was performed to identify reported patients who presented with acute neurological deterioration with radiographic or histopathologic diagnosis of a colloid cyst. Demographic data, presenting symptoms, physical exam, surgical interventions, and outcomes were recorded. Analysis included 140 patients. Mean cyst size was 2.12 cm in males and 1.59 cm in females (p = 0.155), and 1.64 cm in patients who survived and 2.05 cm in patients who died (p = 0.04). Minimum cyst size was 0.4 cm in females and 0.8 cm in males. All patients without surgical intervention died, versus 48% with surgical intervention (p