[Recurrent laryngeal nerve injury following thyroid surgery]

The permanent lesion of damaged recurrent laryngeal nerve (RLN) often manifests as an irreversible dysfunction of phonation and is the most common complication following thyroid surgery. The frequency of this complication ranges from 0.5 to 5% in different thyroid surgery centres and increases in case of both recurrent goiter and complete thyroidectomy due to thyroid cancer. The RLN lesion varies from irreversible, persistent and transient dysfunction with good prognosis of complete recovery. The time of RLN function recovery ranges from several weeks to two years (mainly 6 months). The aim of this study was to evaluate early and persistent RLN paralysis. We operated in our clinic 2323 patients between 1994 and 1997. 2137 patients were operated for the first time due to benign goiter. On the 3rd post-operative day 190 patients (8.9%) presented RLN paralysis of different grade. The follow-up examination (indirect laryngoscopy) was performed in 100 patients with early RLN paralysis in the period between 6 months and 3 years after surgery. The complete RLN recovery was diagnosed in 78%. The permanent paralysis was diagnosed in 1.9% of operated patients. In the light of law and medical aspects we suggest obligatory laryngological examination with the evaluation of vocal cords mobility before surgery and on the 3rd post-operative day in order to identify early RLN lesion. Permanent RLN paralysis may be diagnosed on the basis of multiple laryngological examination in the period between 3 and 24 months after surgery.