Extra-laryngeal branching of recurrent laryngeal nerve: a possibility thyroid surgeons need to keep in mind to prevent inadvertent nerve injury

A 45-year-old woman presented with a neck swelling since the past 6 years. The swelling was painless but slowly and progressively increasing in size. On examination, a thyroid swelling of size approximately 6×4 cm was seen on the left side. Ultrasonography revealed the size to be 6×5 cm with microcalcifications. Fine needle aspiration cytology revealed the mass to be papillary carcinoma. She was planned for total thyroidectomy with central compartment clearance. Preoperative assessment including thyroid hormone profile was normal and the patient was taken for surgery after proper anaesthesia clearance. During the surgery, it was found that there was a branching of the left recurrent laryngeal nerve. The branching was confirmed with nerve monitor and careful dissection was done to prevent injuries. The surgery was completed successfully without any nerve damage and the postoperative period was uneventful. Follow-up assessments revealed no signs of nerve injury like hoarseness of voice. Possibility of abnormal branches and duplication of nerves though uncommon should not be underestimated and extra vigilance and caution must be exercised when operating near a nerve, even by an experienced surgeon familiar with the local anatomy. Any doubts arising during the surgery must be clarified immediately, and nerve monitors should be used to check suspected branching and duplications before proceeding further.