[Unilateral laryngeal paralysis after intra capsular loboisthmectomy without laryngeal nerve dissection]

To document the incidence, outcome and variables that increase the risk for unilateral laryngeal paralysis after loboisthmectomy performed according to the intracapsular dissection technique.

A retrospective analysis of an inception cohort of 317 loboisthmectomies consecutively performed at a single institution by the same surgeon during the years 2002-2007 using the intra capsular dissection without laryngeal nerve dissection, neuromonitoring and modern hemostasis techniques (Ligasure, Ultracision). The immediate and definite rate for unilateral laryngeal nerve paralysis is documented. A statistical analysis is performed for potential relation between these events and the following variables: age, gender, comorbidity, tracheal compression and intrathoracic characteristics of the thyroid lesion, side of the loboisthmectomy, etiology of the thyroid lesion (benign, malignant, hyperthyroidy), associated thyroiditis, size of the largest resected nodule and weight of the resected lobe.

The immediate unilateral laryngeal nerve paralysis incidence was 1,2%. Recovery of motion occurred by the 1st, 3rd, 5th or 9th post operative month resulting in a 0% incidence for definitive unilateral laryngeal nerve paralysis. No significant statistical relation was noted between immediate unilateral laryngeal nerve paralysis and the variables under analysis.

Based on the current series and the review of the medical literature, it appears that the loboisthmectomy according to the intra capsular technique without inferior laryngeal nerve identification, in patients not previously operated, performed according to is a surgical technique whose goal is to ascent the thyroid lobe and dissect the region of the nerve penetration within the larynx by the end of the resection, does not increase the risk for transient or permanent unilateral laryngeal nerve paralysis.