Tri-modality visualization improves blood loss control and facial nerve outcomes in vestibular schwannoma surgery: a retrospective controlled study.

BACKGROUND

This study aims to evaluate the feasibility and potential advantages of a triple-scope cooperative technique versus conventional microscopic surgery for large vestibular schwannomas by comparing their clinical outcomes including tumor resection rate, operative time, intraoperative blood loss, neurological function preservation, and perioperative complications.

METHODS

This retrospective controlled cohort study enrolled 64 consecutive patients with large (Koos grade III-IV) vestibular schwannomas. Although non-randomized, patients were sequentially allocated, based on the chronological introduction of the surgical techniques, to either the conventional microscope-alone group (n = 45) or the novel triple-scope group (n = 19; integrating a 3D exoscope, neuroendoscope, and operative microscope). Therefore, the treatment period and the visualization strategy were inherently linked.To minimize learning curve bias, all operations were performed by a highly experienced skull base surgical team (surgeons with >200 VS surgeries each, at a technical plateau).The primary outcomes evaluated included operative time, intraoperative blood loss, extent of tumor resection, postoperative facial and acoustic nerve function, and perioperative complication rates.

RESULTS

No significant differences were observed between the two groups regarding gross total resection (GTR) rates (95% vs. 82%, P = 0.260) or operative duration. However, the triple-scope group demonstrated significantly lower intraoperative estimated blood loss (195± 52 mL vs. 349 ±108 mL, P < 0.001). Furthermore, the rate of favorable facial nerve function (House-Brackmann Grade I-II) at 6 months was significantly higher in the triple-scope group (84% vs. 40%, P = 0.002). Hearing preservation and overall complication rates remained comparable.

CONCLUSION

Compared with microscopy alone, the triple-scope combination is a feasible strategy for large (Koos grade III-IV) vestibular schwannomas. It is associated with reduced intraoperative blood loss and shows improved short- and mid-term facial nerve recovery without prolonging operative time. However, the present data do not provide sufficient evidence to conclude a definitive reduction in perioperative complications. By integrating complementary visualization strengths, this approach may help reduce concealed areas, representing a multimodal strategy for functional preservation-oriented microsurgery.