ABSTRACT
<p><b>OBJECTIVE</b>To study the surgical treatment of recurrent laryngeal nerve (RLN) injury caused by thyroid operation.</p><p><b>METHODS</b>From 1970 to 2001, 50 patients with RLN injury were caused by thyroid operation. The causes, location, type, operative procedures and follow-up were retrospectively analyzed.</p><p><b>RESULTS</b>Unilateral RLN injury occurred in 46 cases and bilateral nerve injury in 4 cases. The RLN injuries were located within 2cm below the point of RLN entering to throat in 45 nerves (83.3%), other places in 6 nerves (11.3%), and unknown location in 3 nerves (5.4%). Transection of the nerve was found in 19 nerves (36.5%), suture or scare pressing the nerve in 35 nerves (64.8%). All the injured nerves were repaired surgically. Meanwhile all 4 patients with bilateral RLN injuries underwent tracheotomy. Of the 50 cases, 44 cases (88.0%) were followed up for more than 1.5 years. Among the 44 followed-up patients, phonation was restored to normal or obvious improvement in 42 cases (95.5%), and improvement in 2 (4.5%). Of the 35 patients with 39 nerves underwent indirect or direct laryngoscopy, the affected vocal cord movement entirely recovered in 21 cords (53.8%), partially recovered in 7 cords (17.9%), uncovered in 11 cords (28.3%). There was no relation between the recovery of phonation or vocal cord movement with the timing or the procedure of repairing operation.</p><p><b>CONCLUSIONS</b>The location of most RLN injuries caused by thyroid surgery are just below the point of RLN entering to throat, and most are mechanical injury, and need operation to resolve the cause. Once the RLN injury is made, an operation should be performed as early as possible.</p>