The investigational product is dural medical adhesive indicated for watertight sealing of dural defects in spinal surgery to prevent CSF leakage. This superiority trial adopts a prospective, multicenter, single-blind, randomized controlled design with 7 participating neurosurgical centers across China. Eligible patients are adults with visible CSF leakage after one-layer primary dural repair confirmed by intraoperative visualization, Valsalva maneuver or hemostatic sponge test. Subjects are randomly assigned 2:1 via sealed envelopes to two groups.
Intervention group: standard primary dural repair + dural medical adhesive evenly coated on the repair site for instant watertight sealing; a second application is allowed if persistent leakage occurs after first use.
Control group: standard treatment including autologous fat/fascia/muscle graft or reinforced suture after primary repair without medical adhesive.
All participants receive follow-up at postoperative day 10±5 (Visit 1) and day 90±7 (Visit 2). Primary efficacy endpoint is intraoperative successful watertight sealing without CSF leakage. Secondary endpoints include postoperative CSF leakage incidence at two time points, postoperative drainage volume and indwelling duration, and overall safety profiles including all adverse events and serious adverse events within 90 days post-operation. Statistical analyses will be performed on Full Analysis Set (FAS) and Per Protocol Set (PPS) for efficacy, and Safety Set (SS) for safety evaluation.