ABSTRACT
The involvement of the inferior or recurrent laryngeal nerve (RLN) in mobility derangement of the vocal folds occurs more frequently due to thyroid malignancy invasion. Although uncommon, the same derangement, which is caused by benign thyroid entities, is also described and reverts to normality after a thyroidectomy in up to 89% of cases. In these cases, the pathogenesis of the vocal cord mobility disturbance is attributed to the direct compression of the RLN by massive thyroid enlargement. The authors describe three cases of patients presenting unilateral vocal cord palsy, which, before surgery, was diagnosed by laryngoscopy concomitantly with large and compressive goiter. Vocal fold mobility became normal after the thyroidectomy in all three cases. Therefore, it is noteworthy that these alterations may present reversibility after appropriate surgical treatment. An early surgical approach is recommended to reduce the nerve injury as much as possible; to preserve the integrity of both RLNs since the nerve function will be restored in some patients.
ABSTRACT
To determine the point of entrance of the thoracic duct in the venous system, as well as to evaluate some biometric measurements concerning its terminal portion, we conducted an anatomic study on 25 non-preserved cadavers. The termination of the thoracic duct occurred on the confluence between the left internal jugular vein and the left subclavian vein in 60 % of the individuals. The average results for the biometric measurements were: distance between the end of left internal jugular vein and omohyoid muscle 31.2 ± 2.7 mm; distance between the end of thoracic duct and the left internal jugular vein 0.0 ± 0.0 mm; distance between the end of thoracic duct and the left subclavian vein 3.6 ± 1.0 mm; distance between the end of thoracic duct and the left brachiocephalic vein 10.7 ± 3.1 mm. Moreover, it was identified that the left internal jugular vein length in level IV, measured between its entrance in the left subclavian vein and the omohyoid muscle, was able to predict the termination of the thoracic duct on the junction between the left internal jugular vein and the left subclavian vein (OR = 2.99) with high accuracy (79.3 %). In addition, the left internal jugular vein length at level IV was able to predict the localization of thoracic duct termination. Thus, this finding has practical value in minimizing the risk for a potential chyle leak during or after a left-sided neck dissection.
