Surgical Treatment of Spontaneous Intracranial Hypotension: Clinical Characteristics and Outcomes in a Surgically Treated Cohort of Type 1 and Type 3 Leaks

Background/Objectives: Spontaneous intracranial hypotension (SIH) is a functionally limiting condition caused by cerebrospinal fluid leakage. This study aims to evaluate the clinical outcomes of surgical management based on precise leak localization and to describe the characteristics of a surgically treated SIH cohort. Methods: We enrolled 23 patients who underwent surgical treatment for SIH between March 2024 and November 2025. Clinical outcomes included maximum headache severity and total daily upright hours. Radiologic outcomes were evaluated using the Bern score and the resolution of spinal extradural fluid at 2 months postoperatively. Results: The cohort comprised 19 patients (82.6%) with Type 1 and four patients (17.4%) with Type 3 leak. Exploratory subgroup analyses suggested that patients with Type 3 leak were significantly older (mean 65.3 vs. 38.2 years, p < 0.01) with lower thoracic leak (p = 0.02) compared to Type 1 patients. In the 20 patients who completed follow-up, significant improvements were observed in maximum headache intensity (Numeric Rating Scale 4.6 to 1.4, p < 0.01), daily upright time (3 to 12 h, p < 0.01), and Bern score (3.4 to 0.9, p < 0.01). Postoperative rebound headache occurred in 52.2% of patients. Complete resolution of spinal epidural fluid was achieved in 87.5% of Type 1 patients and normalization of the Bern score was achieved in all Type 3 patients. Conclusions: Surgical intervention based on precise leak localization offers substantial clinical and radiological benefits for SIH patients refractory to conservative management. These findings support a treatment-oriented approach based on precise leak localization in patients with SIH.