During a thyroidectomy, the surgeon might remove all of the thyroid gland or only the part that is diseased.
The entire gland is removed for thyroid cancer treatment. 
The laryngeal nerve (voice box nerve) is close to the site of surgery. After the operation, swelling of the nerve might cause weakness or paralysis of the vocal cords. But this is not common and rarely permanent.
Intraoperative Recurrent Laryngeal Nerve Monitoring is the latest technological tool used to prevent damage to the laryngeal nerve during surgery. Electrodes are placed near the muscles of the vocal cords and attached to a computer. The laryngeal nerve is monitored continually. If the nerve is inadvertently disturbed, the technician will alert the surgeon.
- Removes the entire thyroid gland.
- After surgery, patients must take a thyroid hormone pill every day.
- This operation is used for thyroid cancer and large non-cancerous tumors.
Low blood calcium levels (hypocalcemia) may occur when the entire thyroid gland is removed. This condition is usually temporary, but may require calcium supplements. Permanent hypocalcemia is rare.
One side (a lobe) of the thyroid gland is removed.
This operation is used if only one nodule is found in the thyroid gland.
The removal of a thyroid lobe and the part that connects the two lobes (the isthmus).
More thyroid tissue is removed than in a lobectomy.
After surgery, radioactive iodine is used to eliminate any thyroid cells that might be hidden in the body or could not be removed during the operation.
A single radioactive iodine pill is taken four to six weeks after the thyroid operation. The remaining thyroid cells will absorb the radioactive iodine and be eliminated.
Thyroid cells are the only cells able to absorb iodine, so the iodine pill will not harm any other cells in the body. Radioactive iodine causes no hair loss and no nausea.
