A 47-year-old woman comes to the physician with pain in her neck. Physical examination shows an enlarged thyroid gland on the left side and displacement of the trachea. An x-ray of the chest shows a tracheal deviation to the right and a biopsy shows a benign tumor. Which of the following structures will most likely be compressed by the enlarged thyroid gland?

A 29-year-old woman comes to the physician for a follow-up examination, two weeks after undergoing a thyroidectomy. She was diagnosed with intractable Graves disease. She says her wound has healed well and she has noticed a significant improvement in her symptoms, but her voice has become hoarse and has not improved. Which of the following nerves was most likely injured during the operation? 

A 35-year-old woman is brought to the emergency department after being involved in a motor vehicle collision. On arrival, the patient is unconscious with an upper airway obstructed by blood and mucus. After vacuum suctioning, a midline tracheostomy inferior to the thyroid gland isthmus is performed to secure her airway. Which of the following vessels are most likely to be present at the site of incision and will need to be cauterized? 

A 55-year-old woman comes to the physician because of swelling in her neck. Her vital signs are within normal limits. Physical examination shows a non-tender mass on the right side of the patient’s neck. An ultrasound examination of the neck shows a thyroid gland mass. A biopsy of the lesion shows a thyroid gland cancer. She subsequently undergoes a thyroidectomy. Three days after the thyroidectomy, a CT-scan of the head shows air bubbles. Which of the following is the most likely cause of the air bubbles?

A 3-month-old boy is brought to the physician because of a lump in his neck. His vital signs are within normal limits. Physical examination shows a soft mass of tissue on the neck and a biopsy of the mass shows ectopic thymus tissue. Which other developmentally related structure could also have an ectopic location?