Safety and usefulness of an electric knife during surgery for parotid benign tumor: postoperative facial paresis and its risk factors

Conclusion. The incidence of facial nerve paresis was not high compared with previously reported incidences using conventional operative techniques, showing the safety of the use of an electric knife in this operative technique. An electric knife is provided in almost all operating rooms and no special apparatus is necessary for this technique. Background. Since the glandular tissue of the parotid gland is rich in blood flow, safe and accurate protection of the nerve is often made difficult due to bleeding during parotid surgery. Therefore, we developed a technique in which glandular tissue is cut using an electric knife, which is provided in almost all operating rooms. Patients and methods. In this study, the safety and usefulness of an electric knife in parotid surgery were confirmed by evaluating patients with parotid benign tumor who underwent surgery using an electric knife. The subjects were 135 patients with parotid benign tumors. Results. Postoperative facial nerve paresis developed in 36 (26.6%) of the 135 patients but was transient in all cases. Depending on the tumor site, transient paresis was observed in 8 of the 13 patients with tumors in the deep lobe but in 28 (22.9%) of the 122 patients with tumors in the superficial lobe. The mean recovery time from facial nerve paresis was 6.1 weeks.