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). Other indications for surgery include cosmetic (very enlarged thyroid), or symptomatic obstruction (causing difficulties in swallowing or breathing). One of the complications of "thyroidectomy" is voice change and patients are strongly advised to only be operated on by surgeons who protect the voice by using electronic nerve monitoring. Most thyroidectomies are now performed by minimally invasive surgery using a cut in the neck of no more than 2.5 cms(1 inch).

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 mobilisation. It is done in nontoxic MNG. role is controversial.
4. Near total thyroidectomy - Both lobes except the lower pole which is very close to recurrent laryngeal nerve and parathyroid is removed. In papillary carcinoma thyroid.
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. Thyrotoxic crisis/Thyroid storm
3. 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 on removal of the tracheal tube and is a surgical emergency: an emergency tracheostomy must be performed. Recurrent Laryngeal nerve injury may occur during the ligature of the inferior thyroid artery.
4. Hypoparathyroidism temporary (transient) in many patients, but permanent in about 1-4% of patients
5. Anesthetic complications
6. Infection
7. Stitch granuloma
8. Chyle leak
9. Haemorrhage/Hematoma
   • This may compress the airway, becoming life-threatening. A suture removal kit should be kept at the bedside throughout the postoperative hospital stay.
10. Surgical scar/keloid
11. Removal of parathyroids by mistake along with thyroids.

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
• New York Center for Advanced Parathyroid Surgery
• Minimally Invasive Endoscopic Video Assisted Thyroid & Parathyroid Removal Surgery
• Robot-Assisted Endoscopic Thyroid Surgery with No Neck Incisions
• Thyroid Surgery Tutorial From the Patient Education Institute
• Minimally invasive and daycase thryroid surgery Comprehensive information from a UK Specialist Surgeon