LAUSR

Dear Editor, Recurrent laryngeal nerve paralysis remains to be a significant complication following esophagectomy and esophageal reconstruction. The incidence of recurrent laryngeal nerve paralysis after esophagectomy is highly variable in the literature (7.5–80%) (Baba et al., 1999). Traction injury, contusion, thermal damage, impaired vascular supply of the nerve, iatrogenic transection, or compression may all cause recurrent laryngeal nerve paralysis. Injury to the nerve can result in voice changes such as hoarseness and patients may experience difficulty with talking which effects quality of life. Due to vocal cord paralysis, patients may complain of choking and aspiration. Inability to close glottic opening causes repeated aspirations and serious pulmonary complications (Gockel, Kneist, Keilmann, & Junginger, 2005). In our unit, a series of 216 patients who had corrosive esophagitis, underwent total esophagectomy and esophageal reconstruction with colon segment interposition between 1985 and 2018. Prior to mobilization of the cervical esophagus, recurrent laryngeal nerve was dissected under surgical microscope using fine microforceps and microscissors (Figure 1). Anastomosis between the transferred colon segment and cervical esophagus or pharynx was performed with handsewn technique after recurrent laryngeal nerve was completely dissected free. In this series, none of the patients had complications such as hoarseness, respiratory difficulty, choking, or aspiration related to recurrent laryngeal nerve injury. In our unit, patients with corrosive esophageal injury are commonly treated with total esophagectomy and intestinal flap reconstruction. Esophagus is totally resected in order to eliminate the risk of future malignant degeneration and long gap of esophageal defect is successfully reconstructed with pedicled colon interposition. Careful preliminary dissection of the recurrent laryngeal nerve allows the surgeon to clearly identify the nerve with direct visualization during following steps of surgery and this reduces the risk of iatrogenic injury to the nerve. Dissection under surgical microscope's magnification has the additional advantage of preservation of epineurial vessels, thus protecting vascularization of the nerve. Use of microforceps and microscissors reduce the risk of traction injury and thermal damage to the nerve. Reports in the literature regarding identification and preservation of the recurrent laryngeal nerve commonly focus on standard surgical dissection, intraoperative nerve monitoring, or use of different surgical devices to reduce thermal damage to the nerve (Koyanagi, Kato, Nakanishi, & Ozawa, 2018). Therefore, dissection of the nerve under surgical microscope is not a frequently used technique. Most of the studies involve patients with esophageal cancer and the incidence of recurrent laryngeal nerve paralysis after esophagectomy can be reduced to 0–17% with intraoperative nerve monitoring (Garas et al., 2013). Up to our knowledge, dissection of the recurrent laryngeal nerves under surgical microscope with micro instruments during esophagectomy and esophageal reconstruction has not been described previously. We believe our approach provides a safe and practical method for reducing the risk of recurrent laryngeal nerve injury related complications.