Laryngeal nerve monitoring and minimally invasive thyroid surgery: Complementary technologies

Objective: To determine the feasibility of the combined use of laryngeal nerve monitoring and minimally invasive thyroid surgery. Design: Prospective, nonrandomized analysis of single-surgeon experience. Setting: Academic institution. Patients: Consecutive series of patients undergoing both minimally invasive thyroid surgery and laryngeal nerve monitoring. Main Outcome Measures: Incision length and incidence of temporary or permanent laryngeal nerve injury. Results: Two hundred eighty-three patients underwent thyroid surgery at the Medical College of Georgia, Augusta, between January 2004 and November 2006. Some type of minimal-access approach (endoscopic or nonendoscopic) was used in 137 cases (48.4%) in which general anesthesia was administered. Laryngeal nerve monitoring was performed in 73 (53.3%) of these 137 cases, although the proportion of cases in which it was performed increased significantly from 8.7% (2 of 23 cases) in 2004 to 95.2% (58 of 61 cases) in 2006 (P < .001). There were no cases of permanent nerve injury. The incidence of temporary recurrent laryngeal nerve paresis was 4.3% (4 of 92 nerves at risk) in the cases in which laryngeal nerve monitoring was used and 6.0% (5 of 84 nerves at risk) in the cases in which the nerve was visually identified without use of a monitor. This difference failed to reach statistical significance (P = .73), which may reflect an insufficient sample size. Conclusion: Monitoring of the laryngeal nerves is feasible in minimal-access thyroid surgery and may serve as a meaningful adjunct to the visual identification of nerves.