Predictive factors of epidural blood patch success in intracranial hypotension syndrome

OBJECTIVE: This study aimed to identify predictors of epidural blood patch (EBP) success in patients with intracranial hypotension syndrome. BACKGROUND: The epidural blood patch remains the gold standard treatment for intracranial hypotension syndrome, yet its effectiveness varies, and predictors of sustained success remain uncertain. METHODS: We performed a single-center retrospective cohort study. We analyzed 139 epidural blood patches performed for non-obstetric intracranial hypotension syndrome between April 2015 and July 2025. Demographic, clinical, biological, radiological, and procedural data were collected. Complete symptom resolution or highly significant improvement at 1 month was defined as treatment success. RESULTS: Among 93 patients, 1-month complete success was achieved after 31% of procedures (43/139). Early improvement within 48 h was associated with higher odds of 1-month EBP success (adjusted odds ratio [aOR] = 9.70, 95% confidence interval [CI]: 3.66-28.96; p < 0.001) as was the occurrence of rebound headache (aOR = 5.34, 95% CI: 1.27-26.44; p = 0.028). Conversely, symptom exacerbation during the Valsalva maneuver was associated with lower odds of 1-month EBP success (aOR = 0.30, 95% CI: 0.10-0.81; p = 0.020). Lower baseline platelet and fibrinogen levels and osteophytic leaks were negatively associated with early effectiveness but not with 1-month outcome. Targeted epidural blood patches and shorter delay from symptom onset to procedure were associated with higher success rates in univariate analysis, though not independently. Model performance was robust with an area under the curve (AUC) of 0.88 (95% CI: 0.80-0.90). No infectious complications were observed; rebound headaches and transient back pain were the most common secondary events. CONCLUSION: Early clinical improvement and rebound headache are strong positive predictors of durable epidural blood patch effectiveness in intracranial hypotension syndrome, whereas Valsalva-related symptom worsening indicates a higher risk of failure. Radiological severity did not predict outcomes in our study. These easily identifiable clinical factors can assist in individualized management and reduce unnecessary repeat procedures.