The clinical and radiological results before and after surgery were compared and analyzed for patients with multilevel lumbar stenosis who underwent bi-portal endoscopic spine surgery (BESS) and microscopic unilateral laminotomy for bilateral decompression (ULBD). We retrospectively identified 47 and 49 patients who underwent BESS and microscopic ULBD, respectively, who were diagnosed with multi-level lumbar stenosis. Clinical outcomes were evaluated using the visual analog scale score for both back and leg pain, and medication (pregabalin) use and Oswestry Disability Index (ODI) scores for overall treatment outcomes were used pre-operatively and at the final follow-up. Radiological outcomes were evaluated as the percentage of dura expansion volume, and percentage preservation of both facets and both lateral recess angles. The follow-up period of patients was about 17.04 months in the BESS group and about 16.90 months in the microscopic ULBD group. The back and leg visual analog scale (VAS) scores and average pregabalin use decreased more significantly in the BESS group than in the microscopic ULBD group (each p-value 0.0443, <0.001, 0.0378). All radiological outcomes were significantly higher in the BESS group than in the ULBD group. The change in ODI in two-level spinal stenosis showed a significantly higher value in the BESS group compared to the microscopic ULBD group (p-value 0.0335). Multilevel decompression with the BESS technique in multiple spinal stenosis is an adequate technique as it shows better clinical and radiological results than microscopic ULBD during a short-term follow-up period.

Cho HW, et al. Investig Magn Reson Imaging. 2015 Dec;19(4):224-230. https://doi.org/10.13104/imri.2015.19.4.224

Purpose Intraoperative bleeding remains a major challenge in lumbar spine surgery, with conventional assessment methods lacking standardization. The Validated Intraoperative Bleeding Severity Scale (VIBe) is a structured five-grade tool developed to objectively assess bleeding severity across surgical fields. This study evaluated the clinical utility of VIBe in lumbar spinal fusion by comparing it with conventional bleeding metrics across various hemostatic strategies, including hypotensive anesthesia and local hemostatic agent use. Methods In this prospective, randomized controlled trial, 70 patients undergoing elective posterior lumbar decompression and fusion were randomized to normotensive or hypotensive anesthesia. Each group was further divided by hemostatic strategy: active agents alone or a combination of active and passive agents. VIBe grades were independently recorded by the surgeon and assistant for each bleeding site. Conventional bleeding metrics—including estimated blood loss (EBL), transfusion volume, and drain output—were also collected. Between group comparisons and inter-rater agreement were assessed, and correlation analysis was performed to evaluate the association between the VIBe and conventional bleeding metrics. Results VIBe grades improved significantly after hemostasis in all patients (p < 0.001). Although intraoperative blood pressures were significantly lower in the hypotensive group, there were no significant differences in transfusion volume, EBL, drain output, or VIBe-based assessments. Outcomes were also comparable between patients receiving combined versus active-only hemostatic agents. Inter-rater agreement for VIBe scores before hemostasis, after hemostasis, and for score changes was near-perfect (κ = 0.934, 0.834, and 0.856 respectively, all p < 0.001). Operator-assigned VIBe scores significantly correlated with EBL (ρ = 0.305, p = 0.010) and transfusion volume (ρ = 0.264, p = 0.027); assistant correlated with EBL (ρ = 0.284, p = 0.017). Conclusion VIBe is a reliable and reproducible tool for intraoperative bleeding assessment in lumbar spine fusion. Active hemostatic agents were effective, and the addition of passive agents offered no measurable advantage.