2026 Proffered Presentations
S129: PROGNOSTIC UTILITY OF THE BLINK REFLEX FOR FACIAL NERVE PRESERVATION IN VESTIBULAR SCHWANNOMA SURGERY: INSIGHTS FROM A FOUR-YEAR REVIEW
Jihad Abdelgadir; Tanner J Zachem; Syed M Adil; Alexandra Hunter; Emanuel Ray; Adedotun Bello; Seeley Yoo; Ellen O’Callaghan; Aden Haskell-Mendoza; Kerri-Anne Crowell; Aatif M Husain; Calhoun D Cunningham III; Patrick J Codd; Ali Zomorodi; C. Rory Goodwin; Duke University
Introduction: This study investigates the prognostic ability of intraoperative blink reflex monitoring in predicting facial nerve outcomes following surgical resection of vestibular schwannoma. Current intraoperative neuromonitoring methods have limitations, and we sought to determine whether intraoperative blink reflex loss is associated with postoperative facial nerve dysfunction and to assess its role as a complementary tool for surgical decision-making.
Methods: A retrospective chart review of adult patients who underwent vestibular schwannoma resection at a single academic center between January 2021 and January 2025 was conducted. Clinical demographics, imaging characteristics, surgical variables, and neuromonitoring data were analyzed. Blink reflex monitoring was performed following supraorbital nerve stimulation via orbicularis oculi recording. Facial nerve function was evaluated with House-Brackman (HB) scores on postoperative day 1, discharge, and ≥6 months. In order to evaluate associations between intraoperative blink reflex loss and longitudinal facial nerve outcomes a generalized estimating equation was used with covariates of tumor size, fundal fluid cap size, age, and brainstem compression.
Results: A total of 165 patients were identified, 154 (93.3%) of whom underwent intraoperative blink reflex monitoring. Of those with blink reflex monitoring 43/154 (27.9%) patients had ipsilateral blink reflex loss. The generalized estimating equation analysis of 122 patients with 324 observations revealed that blink reflex loss independently predicted worse facial nerve outcomes across timepoints (OR = 2.40, 95% CI: 1.02–5.66, p = 0.045). Tumor size, fundal fluid cap size, age, and brainstem compression were not significantly associated with outcomes. After 6 months, the odds of worse facial nerve function improved compared to postoperative day 1 (OR = 0.177, 95% CI: 0.056–0.554, p = 0.003) (Fig 1). HB function is listed in Table 1, all patients were HB 1-2 at baseline.
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Figure 1: Forest Plot of Generalized Estimating Equation Results Demonstrating Significance of Intraoperative Blink Reflex Loss.
| HB Score | POD 1 | Discharge | 6+ Months |
| 1 |
89/165 (54%) |
92/164 (56%) |
100/113 (88%) |
| 2 |
46/165 (28%) |
39/164 (24%) |
9/113 (8.0%) |
| 3 |
16/165 (9.7%) |
16/164 (9.8%) |
3/113 (2.7%) |
| 4 |
10/165 (6.1%) |
8/164 (4.9%) |
1/113 (0.9%) |
| 5 |
2/165 (1.2%) |
6/164 (3.7%) |
0/113 (0%) |
| 6 |
2/165 (1.2%) |
3/164 (1.8%) |
0/113 (0%) |
Conclusions: Loss of the blink reflex intraoperatively is significantly associated with postoperative facial nerve dysfunction in the context of vestibular schwannoma resection. Additionally, blink reflex loss appears to be a stronger predictor of facial nerve function than tumor-related factors. This posits that blink reflex monitoring offers a complementary non-disruptive monitoring adjunct to conventional intraoperative neuromonitoring that may enhance intraoperative decision-making.