Introduction: Chronic subdural hematoma has a high recurrence rate after surgery and postoperative scans often show substantial residuals, eventually leading to a higher rate of reoperation. However, the benefit of post-surgical imaging for patient outcome remains unknown.
Methods: We randomly assigned 368 patients with newly diagnosed chronic subdural hematoma within 48 hours after surgery to either a combined radiological and clinical follow up (CT arm) or a clinical follow up with scans only in case of neurological deterioration (No-CT arm). The primary outcome was the modified Rankin scale (mRS) score at 90 days; this categorical scale measures functional outcome, with scores ranging from 0 (no symptoms) to 6 (death).
Results: A follow-up protocol with CT imaging did not improve the primary outcome; there was no significant between-arm difference for mRS as a categorical variable (p=0.79) or as numerical variable (p=0.37). The proportion of patients who survived without severe disability (mRS 0-3) was 89% in the CT arm and 93% in the No-CT arm (odds ratio 1.4, 95% confidence interval 3.72-0.82, p=0.15). Death occurred in 12 patients in the CT arm and in 8 patients in the No-CT arm (p=0.5). Re-operation for recurrent hematomas was performed in 59 patients in the CT arm and in 39 patients in the No-CT arm ( p=0.055). Complications were seen in 26 patients in the CT-Arm and in 19 patients in the No-CT arm (p=0.34).
Conclusions: Routinely scheduled CT scans after neurosurgical evacuation of chronic subdural haematoma have no benefit on outcome.
Patient Care: According to this RCT, follow up after surgical evacuation of CSH should be based on neurological evaluation alone without routine CT scans.
Learning Objectives: CT scans after evacuation of CSH have no benefit on any outcome parameter and should not be performed routinely.