| 摘要 |
Substernal goiter can be classified as primary or secondary, depending on the site of origin. Primary substernal goiters (< 1% of substernal goiters), also known as mediastinal aberrant goiters, arise from ectopic thyroid tissue in the mediastinum, and receive their blood supply from intrathoracic arteries instead of thyroid arteries. A secondary substernal goiter is defined as one that has descended from the neck to the plane below the thoracic inlet, or one that has more than 50% of its mass lying inferior to the thoracic inlet. Surgical resection should be considered even for elderly patients because of the risks of mass compression symptoms (e.g., dyspnea and dysphasia), malignancy, and low morbidity of surgery. Most of the primary substernal goiters can be resected through the cervical approach. In most instances, sternotomy or thoracotomy is needed only in cases of previous cervical thyroidectomy, invasive carcinoma,
or ectopic goiter. |
