Benign extracerebral fluid collection complicated by subdural hematoma and fluid collection: clinical characteristics and management.

Introduction: Benign extracerebral fluid collection (bECFC) can be complicated by subdural hematoma (SDH) or subdural fluid collection (SDFC). The etiology, natural history, and management strategy for SDH/SDFC in bECFC are not fully understood. We retrospectively reviewed the cases of bECFC patients complicated with SDH/SDFC and tried (1) to confirm the fact that bECFC children are vulnerable to SDH/SDFC, (2) to investigate the clinical significance of 'trauma history' witnessed by a caregiver, and (3) to determine optimal management for them.

Method: Among 213 bECFC patients identified from January 2000 to August 2015, 20 patients (male:female = 14:6; median age, 6.5 months; range 1-16 months) complicated by SDH/SDFC documented with brain imaging were evaluated for their clinical manifestations, radiologic features, and management outcomes. The median follow-up period was 9.5 months. They were divided into two groups (traumatic group versus non-traumatic group) according to whether objective radiologic evidence of head injury was present or not, and the two groups were analyzed for any clinical differences between them. We also evaluated the clinical significance of witnessed traumatic events by caregivers as an additional independent variable in the analysis.

Results: The incidence of SDH/SDFC in bECFC patients was 9.4% (20/213) in our data. In a comparative analysis, the traumatic group is more likely to have 'acute' stage SDH, whereas the non-traumatic group is more likely to have 'chronic' stage SDH. The trauma history witnessed by caregivers did not show clinical significance in the data analysis when included as an independent variable. The prognosis of SDH/SDFC in bECFC patients was favorable without surgery in most of patients regardless of whether the patient has evidence of head trauma or not.

Conclusion: Benign ECFC is vulnerable to SDH/SDFC development. For the bECFC patients complicated by SDH/SDFC, the trauma history witnessed by a caregiver did not show any clinical significance. A 'wait and watch' strategy is sufficient for the management of SDH/SDFC in bECFC patients.