Thyroidectomy

Thyroidectomy
Intervention
ICD-9-CM	06.3-06.5
MeSH	D013965

A thyroidectomy is an operation that involves the surgical removal of all or part of the thyroid gland. Surgeons often perform a thyroidectomy when a patient has thyroid cancer or some other condition of the thyroid gland (such as hyperthyroidism)or goiter. Other indications for surgery include cosmetic (very enlarged thyroid), or symptomatic obstruction (causing difficulties in swallowing or breathing). Thyroidectomy is a common surgical procedure that has several potential complications or sequela including: temporay or permanent change in voice, temporary or permanently low calcium, need for life-long thyroid hormone replacement, bleeding, infection, and the remote possibility of airway obstruction due to bilateral vocal cord paralysis. Complications are uncommon when the procedure is performed by an experienced surgeon.

The thyroid produces several hormones, such as thyroxine (T4), triiodothyronine (T3) and calcitonin.

After the removal of a thyroid patients usually take prescribed oral synthetic thyroid hormones to prevent the most serious manifestations of the resultant hypothyroidism.

Less extreme variants of thyroidectomy include:

• "hemithyroidectomy" (or "unilateral lobectomy") -- removing only half of the thyroid
• "isthmectomy" -- removing the band of tissue (or isthmus) connecting the two lobes of the thyroid

A "thyroidectomy" should not be confused with a "thyroidotomy" ("thyrotomy"), which is a cutting into (-otomy) the thyroid, not a removal (-ectomy) of it. A thyroidotomy can be performed to get access for a median laryngotomy, or to perform a biopsy. (Although technically a biopsy involves removing some tissue, it is more frequently categorized as an -otomy than an -ectomy because the volume of tissue removed is minuscule.)

Indications

• Malignancy (see Thyroid neoplasm)
• Cosmetic reasons
• Goiter which is untreatable by medical methods
• Severe hyperthyroidism refractory to conservative treatment
• Orbitopathy in Graves' disease
• Removal and evaluation of a thyroid nodule whose FNAC results are unclear

Types of Thyroidectomy

1. Hemithyroidectomy - entire isthmus is removed along with 1 lobe. Done in benign diseases of only 1 lobe.
2. Subtotal thyroidectomy - done in toxic thyroid. primary or secondary and also for toxic MNG
3. Partial thyroidectomy - removal of gland in front of trachea after mobilization. It is done in nontoxic MNG. role is controversial.
4. Near total thyroidectomy - Both lobes are removed except for a small amount of thyroid tissue (on one or both sides) in the vicinity of the recurrent laryngeal nerve entry point and the superior parathyroid gland.
5. Total thyroidectomy- Entire gland is removed. Done in case of follicular carcinoma of thyroid, medullary ca of thyroid.
6. Hartley Dunhill operation- removal of 1 entire lateral lobe with isthmus and partial/subtotal removal of opposite lateral lobe. It is done in non toxic MNG.

Steps

Main steps of Thyroidectomy:

1. Exposure - horizontal neck incision, +/- raising of flaps, +/- division of strap muscles
2. Identification of essential structures - Recurrent and ext. branch of superior laryngeal nerve, parathyroid glands
3. Devascularization
   • Superior thyroid artery
   • Inferior thyroid artery while protecting the supply to the parathyroids
   • Thyroid ima if present
4. Resection
5. Exploration of other pathology - e.g. contralateral lobe, lymph nodes
6. Closure

Complications

1. Hypothyroidism/Thyroid insufficiency in up to 50% of patients after ten years
2. Laryngeal nerve injury in about 1% of patients, in particular the recurrent laryngeal nerve: Unilateral damage results in a hoarse voice. Bilateral damage presents as laryngeal obstruction after surgery and can be a surgical emergency: an emergency tracheostomy may be needed. Recurrent Laryngeal nerve injury may occur during the ligature of the inferior thyroid artery.
3. Hypoparathyroidism temporary (transient) in many patients, but permanent in about 1-4% of patients
4. Anesthetic complications
5. Infection
6. Stitch granuloma
7. Chyle leak
8. Haemorrhage/Hematoma
   • This may compress the airway, becoming life-threatening.
9. Surgical scar/keloid
10. Removal or devascularization of the parathyroids.
11. Thyroid storm in operations performed for hyperthyroidism

External links

• Patient brochure from the American Thyroid Association
• Surgical procedures Comprehensible and elaborate information from the New York Thyroid Center
• Article at Endocrineweb, written by an MD Goes into more detail
• Early postoperative scar images
• Thyroid Surgery Tutorial From the Patient Education Institute
• Minimally invasive and daycase thryroid surgery Comprehensive information from a UK Specialist Surgeon