Natural History of Facial Weakness Following Surgery of the Cerebellopontine Angle: A Tertiary Care Cohort

Objective: Facial function is a key outcome in surgery of the cerebellopontine angle (CPA). This study describes the natural history of facial weakness after CPA surgery. Study design and setting: Retrospective study of two tertiary centers. Patients and intervention: Patients undergoing surgery for CPA tumors from 2003 to 2017 with preoperatively normal facial function and without subsequent surgical or adjuvant therapy. Main outcome measure: Serial facial nerve examinations using the House–Brackmann (HB) scale. Results: Of 301 patients examined, 149 (49.5%) had facial weakness postoperatively and 74.5% of these occurred within 24 hours. Of patients with HB-1 function within 24 hours after surgery, 95.3% had HB-1 function and 100% had HB-3 or better function at last follow-up. Of patients with HB-4 or worse function within 24 hours after surgery, 22.6% ultimately achieved HB-1 function and 83.9% ultimately achieved HB-3 or better function. By 180 days postoperatively, 83.7% of patients’ facial function had stabilized. At last follow-up, 3.0% of patients had facial function poorer than HB-3, which was associated with subtotal resections (12.9% vs. 4.4% for near total and 0.6% for gross total resections, p = 0.002), aspirin use (10.6% vs. 1.6%, p = 0.001), larger tumors (p < 0.0005), longer surgery (p < 0.002), and immediate versus delayed postoperative facial weakness (p = 0.002). Conclusions: Facial function over time after CPA surgery is presented. While facial function immediately after surgery correlates with future function, delayed weakness or improvement is common. These data inform patient counseling both preceding and following surgery.