1. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 1
9 THYROID AND PARATHYROID
OPERATIONS
Wen T. Shen, MD, Gregg H. Jossart, MD, FACS, and Orlo H. Clark, MD, FACS
Thyroidectomy are placed on the dermis, and subplatysmal flaps are raised,
first cephalad to the level of the thyroid cartilage notch
operative planning and then caudad to the suprasternal notch. Skin towels and
If the patient has had any hoarseness or has undergone a a self-retaining retractor are applied.
previous neck operation, indirect or direct (ideally, fiberoptic)
laryngoscopy is essential to determine whether the vocal Troubleshooting An incision 1 cm below the cricoid
cords are functioning normally. All patients scheduled for cartilage yields an entry point that is precisely over the
thyroidectomy should be euthyroid at the time of operation. isthmus of the thyroid gland. The course of the incision
Those with hyperthyroidism should be treated with antithy- should conform to the normal skin lines or creases. The
roid medication and Lugol’s iodine, and those with hypothy- length of the incision should be modified as necessary for
roidism should be taking thyroid hormone supplementation. good exposure. Patients with short, thick necks, low-lying
Preanesthetic evaluation should be undertaken as it would be thyroid glands, or large thyroid tumors require longer inci-
for any procedure calling for general anesthesia. sions than those with long, thin necks and small tumors.
Optimal exposure of the neck is obtained by placing a Patients whose necks do not extend also require longer inci-
beanbag or soft roll behind the scapulae and a foam ring sions for adequate exposure. A sterile marking pen should be
under the occiput; placement of these devices extends the used to mark the midline of the neck, the level at which the
neck and places the thyroid gland in a more anterior position. incision should be made (i.e., 1 cm below the cricoid), and
The head must be well supported to prevent postoperative the lateral margins of the incision (which should be at
posterior neck pain. The patient is placed in a 20° reverse equal distances from the midline so that the incision will be
Trendelenburg position. The skin is prepared with 1% iodine symmetrical). A scalpel should never be used to mark the
or chlorhexidine. neck: doing so will leave an unsightly scar in some patients.
operative technique To mark the incision site itself, a 2-0 silk tie can be pressed
against the neck [see Figure 1].
General Troubleshooting The upper flap is dissected first by placing five straight
Thyroid and parathyroid operations should be performed Kelly clamps on the dermis and retracting anteriorly and
in a blood-free field so that vital structures can be identified. superiorly. Lateral traction with a vein retractor or an
Operating telescopes (magnification: x2.5 or x3.5) are also Army-Navy retractor helps identify the semilunar plane for
recommended because they make it easier to identify the dissection. This blood-free plane is deep to the platysma and
normal parathyroid glands and the recurrent laryngeal nerve. superficial to the anterior jugular veins. Cephalad dissection
If bleeding occurs, pressure should be applied. The vessel can be done quickly with the electrocautery or a scalpel, and
should be clamped only if (1) it can be precisely identified or lateral dissection can be done bluntly. The same principles
(2) the recurrent laryngeal nerve has been identified and is are applied to dissection of the lower flap. In thin patients,
not in close proximity to the vessel. the surgeon must be careful not to dissect through the skin
As a rule, dissection should always begin on the side of the from within, especially at the level of the thyroid cartilage.
suspected tumor; if there is a problem with the dissection on
Step 2: Midline Dissection and Mobilization of Strap Muscles
this side, a less than total thyroidectomy can be performed
on the contralateral side to prevent complications. There The thyroid gland is exposed via a midline incision through
is, however, one exception to this rule: if the tumor is very the superficial layer of deep cervical fascia between the strap
extensive, the surgeon will sometimes find it easier to do the muscles. Because the strap muscles are farthest apart just
dissection on the “easy” side first to facilitate orientation with above the suprasternal notch, the incision is begun at the
respect to the trachea and the esophagus. notch and extended to the thyroid cartilage [see Figure 2].
On the side where the thyroid nodule or the suspected
Step 1: Incision and Mobilization of Skin Layers parathyroid adenoma is located, the more superficial sterno-
A Kocher transverse incision paralleling the normal skin hyoid muscle is separated from the underlying sternothyroid
lines of the neck is made 1 cm below the cricoid cartilage muscle by blunt dissection, which is extended laterally until
[see Figure 1]. As a rule, the incision should be about 4 to the ansa cervicalis becomes visible on the lateral edge of the
6 cm long and should extend from the anterior border of sternothyroid muscle and on the medial side of the internal
one sternocleidomastoid muscle to the anterior border of the jugular vein. The sternothyroid muscle is then dissected
other and through the platysma. Five straight Kelly clamps free from the thyroid and the prethyroidal fascia by blunt or
DOI 10.2310/7800.S02C09
07/08

2. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 2
Figure 1 The initial incision in a thyroidectomy is made 1 cm below the cricoid cartilage and follows normal skin lines. A sterile
marking pen is used to mark the midline of the neck, the level of the incision, and the lateral borders of the incision. A 2-0 silk tie is
pressed against the neck to mark the incision site itself.
sharp dissection until the middle thyroid vein or veins are Troubleshooting As noted (see above), the strap
encountered laterally. These maneuvers provide excellent muscles generally need not be divided; however, if they are
exposure; accordingly, we have not found routine division of adherent to the underlying thyroid tumor, the portion of the
the strap muscles to be necessary. muscle adhering to the tumor should be sacrificed and removed
A 2-0 silk suture can be placed through the thyroid lobe for en bloc with the specimen. Separation of the sternohyoid muscle
retraction to facilitate exposure. This stitch should never be from the sternothyroid muscle provides excellent exposure. The
placed through the thyroid nodule: doing so could cause middle thyroid veins should be cleaned of adjacent tissues to
prevent any injury to the recurrent laryngeal nerve when these
seeding of thyroid cancer cells. The thyroid is retracted ante-
veins are ligated and divided. It is always safest to mobilize
riorly and medially and the carotid sheath laterally; this
tissues in a direction parallel to the course of the recurrent
retraction places tension on the middle thyroid veins and laryngeal nerve.
helps expose the area posterolateral to the thyroid, where the
parathyroid glands and the recurrent laryngeal nerves are Step 3: Division of Isthmus
situated. The middle thyroid vein is divided to yield better When a thyroid lobectomy is performed, the isthmus of the
exposure of the upper lobe of the thyroid [see Figure 3]. thyroid gland is usually divided lateral to the midline with
Figure 2 To expose the thyroid, a midline incision is made through the superficial layer of deep cervical fascia between the
strap muscles. The incision is begun at the suprasternal notch and extended to the thyroid cartilage.
07/08

3. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 3
Troubleshooting It is essential to avoid injuring the
external branch of the superior laryngeal nerve. This nerve is
the motor branch of the superior laryngeal nerve and is
responsible for tensing the vocal cords; it is also known as the
high note nerve or the Amelita Galli-Curci nerve (after the
20th-century opera singer who was reputed to have suffered
an injury to this nerve after thyroidectomy). In about 80% of
patients, the external branch of the superior laryngeal nerve
runs on the surface of the cricothyroid muscle; in about 10%,
it runs with the superior pole vessels; and in the remaining
10%, it runs within the cricothyroid muscle. Given that this
nerve is usually about the size of a single strand of a spider
web, one should generally try to avoid it rather than attempt
to identify it. Injury to the external branch of the superior
laryngeal nerve occurs in as many as 10% of patients under-
going thyroidectomy. The best ways of preventing such inju-
ries are (1) to provide gentle traction on the thyroid gland in
a caudal and lateral direction during superior dissection and
(2) to ligate the superior pole vessels directly on the capsule
of the upper pole individually rather than cross-clamp the
entire superior pole pedicle.
Figure 3 The middle thyroid veins are divided to give better
exposure behind the upper lobe of the thyroid.
The internal branch of the superior laryngeal nerve pro-
vides sensory innervation to the posterior pharynx. Injury to
this nerve can result in aspiration. Because the internal branch
of the superior laryngeal nerve typically runs cephalad to the
Dandy or Colodny clamps at an early point in the dissection
thyroid cartilage, it is rarely encountered during a typical thy-
to facilitate the subsequent mobilization of the thyroid gland. roidectomy. Care must be taken to avoid injury to this branch
The remaining thyroid tissue is oversewn with a 2-0 silk when laryngeal mobilization is performed to relieve tension
ligature. To minimize the chance of invasion into the trachea on a tracheal anastomosis after tracheal resection of locally
and to prevent the development of a visible mass from com- advanced thyroid cancer.
pensatory thyroid hypertrophy, thyroid tissue should not be
left anterior to the trachea. Step 5: Identification of Recurrent Laryngeal Nerve and Lower
Parathyroid Gland
Troubleshooting With larger glands, we divide the isthmus The lower parathyroid gland is usually encountered during
first, taking care not to cut across the tumor. This step lateral mobilization of the lower thyroid pole; it is almost always
facilitates the lateral dissection by making the gland more located anterior to the recurrent laryngeal nerve and inferior
mobile. to the point where the inferior thyroid artery crosses the
recurrent laryngeal nerve [see Figure 6]. The carotid sheath is
Step 4: Mobilization of Thyroid Gland and Identification of retracted laterally, and the thyroid gland is retracted anteri-
Upper Parathyroid Gland orly and medially. This retraction puts tension on the inferior
Once the isthmus has been divided, dissection is continued thyroid artery and consequently on the recurrent laryngeal
superiorly, laterally, and posteriorly with a small peanut nerve, thereby facilitating identification of the nerve. The
sponge on a clamp. The superior thyroid artery and veins are recurrent laryngeal nerve is situated more medially on the left
identified by retracting the thyroid inferiorly and medially. (running in the tracheoesophageal groove) and more obliquely
The tissues lateral to the upper lobe of the thyroid and on the right. Dissection should proceed cephalad along the
lateral edge of the thyroid gland. Fatty and lymphatic tissues
medial to the carotid sheath can be mobilized caudal to the
immediately adjacent to the thyroid gland are swept from it
cricothyroid muscle; the recurrent laryngeal nerve enters the
with a peanut clamp, and small vessels are ligated. No tissue
cricothyroid muscle at the level of the cricoid cartilage, first
should be transected in this area until one is sure that it is not
passing through Berry’s ligament [see Figure 4]. The superior
the recurrent laryngeal nerve.
pole vessels are individually identified, skeletonized, double-
or triple-clamped, ligated, and divided low on the thyroid Troubleshooting The upper parathyroid glands are usu-
gland [see Figure 5]. To prevent injury to the external branch ally situated on each side of the thyroid gland at the level
of the superior laryngeal nerve as it traverses the anterior where the recurrent laryngeal nerve enters the cricothyroid
surface of the cricothyroid muscle, the superior pole vessels muscle [see Figure 6]. Because the recurrent laryngeal nerve
are divided and ligated close to the thyroid surface. The enters the cricothyroid muscle at the level of the cricoid carti-
tissues posterior and lateral to the superior pole that have lage, the area cephalad to the cricoid cartilage is relatively safe,
not already been mobilized can now be easily swept by blunt though care should be taken to avoid injury to the external
dissection away from the thyroid gland medially and anteri- branch of the superior laryngeal nerve (see above).
orly and away from the carotid sheath laterally. The upper The right and left recurrent laryngeal nerves must be
parathyroid gland is often identified at this time at the level preserved during every thyroid operation. Although both
of the cricoid cartilage. nerves enter at the posterior medial position of the larynx in
07/08

4. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 4
Figure 4 The recurrent laryngeal nerve enters the cricothyroid muscle at the level of the cricoid cartilage, first passing through
Berry’s ligament.
the cricothyroid muscle, their courses vary considerably. The on the right. The left recurrent laryngeal nerve almost always
right recurrent laryngeal nerve takes a more oblique course runs in the tracheoesophageal groove because of its deeper
than the left recurrent laryngeal nerve does and may pass origin within the thorax as it loops around the ductus arterio-
either anterior or posterior to the inferior thyroid artery. In sus. Either recurrent laryngeal nerve may branch before enter-
about 0.5% of the population, the right recurrent laryngeal ing the larynx; the left nerve is more likely to do this. Such
nerve is in fact nonrecurrent and may enter the thyroid from branching is important to recognize because the motor fibers
a superior or lateral direction. On rare occasions, both a of the recurrent laryngeal nerve are usually located within the
recurrent and a nonrecurrent laryngeal nerve may be present most medial branch.
Figure 5 The superior pole vessels should be individually identified and ligated low on the thyroid gland to minimize the
chances of injury to the external branch of the superior laryngeal nerve.
07/08

5. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 5
Figure 6 The upper parathyroid glands are usually situated on either side of the thyroid at the level where the recurrent
laryngeal nerve enters the cricothyroid muscle. The lower parathyroid glands are usually anterior to the recurrent laryngeal
nerve and inferior to where the inferior thyroid artery crosses this nerve.
In identifying the recurrent laryngeal nerves, it is helpful to with minimal manipulation and with its remaining blood supply
remember that they are supplied by a small vascular plexus preserved.
and that a tiny vas nervi runs parallel to and directly on In patients who have large thyroid tumors or thyroiditis or
each nerve [see Figures 4 and 6]. In young people, the artery who have previously undergone a neck operation, extensive
usually is readily distinguished from the recurrent laryngeal scarring is often present. For some of these patients, it is
nerve; however, in older persons with arteriosclerosis, the preferable to identify the recurrent laryngeal nerve via a
white-appearing artery may be mistaken for a nerve, and thus medial approach by dividing the isthmus with Colodny
the nerve may be injured as a result of the misidentification. clamps and ligating and dividing the superior thyroid vessels.
Lateral traction on the carotid sheath and medial and anterior By carefully dissecting the thyroid away from the trachea, one
traction on the thyroid gland place tension on the inferior can identify the recurrent laryngeal nerve at the point where
thyroid artery; this maneuver often helps identify the recur- its position is most consistent (i.e., at its entrance into the
rent laryngeal nerve where it courses lateral to the midportion larynx immediately posterior to the cricothyroid muscle).
of the thyroid gland. One should, however, be careful not to The most difficult dissection in a thyroidectomy is in the
devascularize the inferior parathyroid glands by dividing the
area of Berry’s ligament, which is situated at the posterior
lateral vascular attachments. To remove the thyroid lobe, it
portion of the thyroid gland just caudal to the cricoid carti-
is best to divide the vessels directly on the thyroid capsule
lage [see Figure 4]. A small branch of the inferior thyroid
to preserve the blood supply to the parathyroid glands. It is
artery traverses the ligament, as do one or more veins from
usually safest to identify the recurrent laryngeal nerve low in
the thyroid gland. If bleeding occurs during this part of the
the neck and then to follow it to the site where it enters the
cricothyroid muscle through Berry’s ligament. The recurrent dissection, it should be controlled by applying pressure with
laryngeal nerves can usually be palpated through the sur- a gauze pad. Nothing should be clamped in this area until the
rounding tissue in the neck; they feel like taut ligatures of recurrent laryngeal nerve is identified. In some patients (about
approximately 2-0 gauge. 15%), the peduncle of Zuckerkandl, a small protuberance of
Parathyroid glands should be swept from the thyroid gland thyroid tissue on the right, tends to obscure the recurrent
on as broad a vascular pedicle as possible to prevent devas- laryngeal nerve at the level of Berry’s ligament.
cularization. When it is unclear whether a parathyroid gland
Step 6: Mobilization of Pyramidal Lobe
can be saved on its own vascular pedicle, the gland should
undergo a biopsy to confirm that it is parathyroid and then The pyramidal lobe is found in about 80% of patients. It
be autotransplanted in multiple 1x1 mm pieces into separate extends in a cephalad direction, often through the notch in
pockets in the sternocleidomastoid muscle; the muscle pocket the thyroid cartilage to the hyoid bone. One or more lymph
should be marked with a clip or stitch in case removal subse- nodes are frequently found just cephalad to the isthmus of
quently proves necessary. At times, it is preferable to clip the the thyroid gland over the cricothyroid membrane (so-called
blood vessels running from the thyroid to the parathyroid glands Delphian nodes) [see Figure 7]. The pyramidal lobe is mobilized
rather than to clamp and tie them. Clipping not only marks the by retracting it caudally and by dissecting immediately adja-
parathyroid gland (which is useful if another operation subse- cent to it in a cephalad direction. Small vessels are coagulated
quently becomes necessary) but also enables the gland to remain or ligated.
07/08

6. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 6
Figure 7 Delphian lymph nodes may be found just cephalad to the isthmus over the cricothyroid membrane.
Step 7: Thyroid Resection prevent tension on the anastomosis, the trachea should be
Once the parathyroid glands have been carefully swept or mobilized before resection, the recurrent laryngeal nerves
dissected from the thyroid gland and the recurrent nerve has should be preserved and mobilized from the trachea, and the
been identified, the thyroid lobe can be quickly resected. For mylohyoid fascia and muscles should be divided above the
a total thyroidectomy, the same steps are repeated on the thyroid cartilage to drop the cartilage. Special care must be
other side. taken to not injure the internal branch of the superior laryn-
geal nerve during this dissection, given that this nerve courses
Troubleshooting The thyroid lobe or gland should be from lateral to medial just above the lateral aspect of the
carefully examined after removal. If a parathyroid gland is thyroid cartilage. After resection, the trachea is reapproxi-
identified, a biopsy should be performed to confirm that it is mated with 3-0 polyglyconate sutures. One or two Penrose
parathyroid, and the gland should be autotransplanted. In a drains should be left near the resection site to allow air to exit.
thyroid operation, every parathyroid gland should be treated The drains are removed after several days, when there is no
as if it is the last one, and at least one parathyroid gland more evidence of air leakage.
should be definitively identified. As a rule, a biopsy should If the esophagus is invaded by tumor, the muscular wall of
not be performed on a normal parathyroid gland during a the esophagus can be resected along with the tumor, with the
thyroid operation unless the gland has been devascularized inner mucosa left in place (unless it too is involved with
and autotransplantation is planned. tumor).
Step 8: Closure
Neck Dissection for Nodal Metastases Lymph nodes
The sternothyroid muscles are approximated with 4-0 in the central neck (medial to the carotid sheath) are
absorbable sutures, and a small opening is left in the midline
frequently involved in patients with papillary, medullary, and
at the suprasternal notch to make any bleeding that occurs
Hürthle cell cancer. These nodes should be removed without
more evident and to allow the blood to exit. The sternohyoid
injury to the parathyroid glands or the recurrent laryngeal
muscles are reapproximated in a similar fashion, as is the
nerves. In most patients it is relatively easy to remove all
platysma. The skin is then closed with butterfly clips, which
tissue between the carotid sheath and the trachea. In some
are hemostatic and inexpensive and permit precise alignment
patients with extensive lymphadenopathy, it is necessary
of the skin edges. If these clips are not available, the skin can
to remove the parathyroids, perform biopsies on them to
be closed with a subcuticular stitch and Steri-Strips instead.
confirm that they are in fact parathyroid, and autotransplant
A sterile pressure dressing is applied.
them into the sternocleidomastoid muscle.
Special Concerns When lymph nodes are palpable in the lateral neck, a
Invasion of Trachea or Esophagus On rare occasions, modified neck dissection is performed through a lateral exten-
thyroid or parathyroid cancers may invade the trachea or the sion of the Kocher collar incision to the anterior margin of
esophagus. As much as 5 cm of the trachea can be resected the trapezius (a MacFee incision). The jugular vein, the
safely without impairment of the patient’s voice. If the inva- spinal accessory nerve, the phrenic nerve, the vagus nerve, the
sion is not extensive and is confined to the anterior portion cervical sympathetic nerves, and the sternocleidomastoid
of the trachea, a small section of the trachea that contains the muscle are preserved unless they are directly adherent to or
tumor should be excised, and a tracheostomy may be placed invaded by tumor.
at the site of resection. If the invasion is more extensive or In patients with medullary thyroid cancer, a meticulous
occurs in the lateral or posterior portion of the trachea, a and thorough central neck dissection is necessary. When a
segment of the trachea measuring several centimeters long is primary medullary tumor is larger than 1 cm or the central
resected, and the remaining segments are reanastomosed. To neck nodes are obviously involved, these patients will also
07/08

7. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 7
benefit from an ipsilateral functional neck dissection (with outcome evaluation
preservation of the aforementioned structures). During the dis- The duration of a typical thyroid operation is 1 to 3 hours,
section, all fibrofatty lymph node tissues should be removed depending on the size and invasiveness of the tumor, its vascu-
from the level of the clavicle to the level of the hyoid bone. larity, and the location of the parathyroid glands. Postopera-
The deep dissection plane is developed anterior to the scale- tively, the patient is kept in a low Fowler position with the head
nus anterior, the brachial plexus, and the scalenus medius. and shoulders elevated 10° to 20° for 6 to 12 hours to maintain
The phrenic nerve runs obliquely on the scalenus anterior. negative pressure in the veins. The patient typically resumes
The cervical sensory nerves can usually be preserved unless eating within 3 to 4 hours, and an antiemetic is ordered as
there is extensive tumor involvement. needed (many patients experience postoperative nausea and
emesis).
Median Sternotomy A median sternotomy is rarely The serum calcium level is measured approximately 5 to 8
necessary for removal of the thyroid gland, because the blood hours after operation in patients who have undergone bilat-
supply to the thyroid gland, the thymus, and the lower para- eral exploration; no tests are required in those who have
thyroid glands originates primarily from the inferior thyroid undergone a unilateral operation. On the first morning after
arteries in the neck. Metastatic lymph nodes frequently extend total or completion thyroidectomy, the serum calcium and
inferiorly in the tracheoesophageal groove into the superior serum phosphate levels are measured. If the patient is still
mediastinum; these nodes can almost always be removed hospitalized on postoperative day 2, these tests may be
through a cervical incision without any need for a sternotomy. repeated. Oral calcium supplements are given if the serum
On rare occasions, metastatic nodes spread to the aortic pul- calcium concentration is below 7.5 mg/dL or if the patient
monary window and can be identified preoperatively on com- experiences perioral or finger numbness or tingling. A low
puted tomography (CT) or magnetic resonance imaging serum phosphate level (< 2.5 mg/dL) usually is a sign of
(MRI). If a median sternotomy proves necessary, the sternum so-called bone hunger and suggests that there is little reason
should be divided to the level of the third intercostal space to be concerned about permanent hypoparathyroidism,
and then laterally on one side at the space between the third whereas a high level (> 4.5 mg/dL) should prompt concern
and fourth ribs. Median sternotomy provides excellent expo- about possible permanent hypoparathyroidism.
sure of the upper anterior mediastinum and the lower neck. The surgical clips are removed on postoperative day 1, and
Steri-Strips are applied to prevent tension on the healing wound.
complications Patients usually are discharged on the first day; they are given a
The following are the most significant complications of prescription for thyroid hormone (L-thyroxine, 0.1 to 0.2 mg/
thyroidectomy. day orally) if the procedure was more extensive than a thyroid
lobectomy, and are instructed to take calcium tablets for any
1. Injury to the recurrent laryngeal nerve. Bilateral injury to the tingling or muscle cramps. Patients with papillary, follicular,
recurrent laryngeal nerves may result in vocal cord paresis or Hürthle cell cancer should receive enough L-thyroxine to
and stridor and may necessitate tracheostomy. keep their serum levels of thyroid-stimulating hormone (TSH)
2. Hypoparathyroidism. This complication may arise as the below 0.1 mIU/mL. The Steri-Strips are removed on day 10,
result of removal of, injury to, or devascularization of the the pathology is reviewed, and further management is discussed
parathyroid glands. As noted [see Operative Technique, in the light of the pathology findings. In patients with thyroid
above], we recommend leaving parathyroid glands on their cancer, values for serum calcium, TSH, and thyroglobulin are
own vascular pedicle; however, if one is concerned about obtained; in patients with coexisting hyperparathyroidism, values
possible devascularization of a parathyroid, biopsy should be for serum calcium, phosphorus, and parathyroid hormone
performed on the gland to confirm its identity, and it should (PTH) are obtained.
then be cut into multiple 1x1 mm pieces and autotrans- Most patients can return to work or full activity within 1 week.
planted into separate pockets in the sternocleidomastoid Patients with benign lesions who have undergone hemithyroid-
muscle. ectomy may or may not require thyroid hormone; those with
3. Bleeding. Postoperative bleeding in the neck can be life- multinodular goiter, thyroiditis, or occult papillary cancer typi-
threatening because of airway compromise. Any postopera- cally do, whereas those with follicular adenoma typically do not.
tive respiratory distress is due to neck hematoma until proven Patients who have undergone total or near-total thyroidectomy
otherwise. Most bleeding occurs within four hours of opera- will require thyroid hormone. Patients with papillary or follicular
tion, and virtually all episodes occur within 24 hours unless cancer who have undergone total or near-total thyroidectomy
the patient is taking anticoagulant medications. appear to benefit from radioactive iodine scanning and therapy.
4. Injury to the external branch of the superior laryngeal (It is necessary to discontinue L-thyroxine for 6 to 8 weeks and
nerve [see Operative Technique, above]. L-triiodothyronine for 2 weeks before scanning.) Those consid-
5. Infection. This complication is quite rare after thyroidec- ered to be at low risk (age < 45 years, tumor confined to the
tomy. If acute pharyngitis is present preoperatively, the thyroid and not invasive, and tumor diameter < 4 cm) may
operation should be rescheduled. receive radioactive iodine on an outpatient basis in a dose of
6. Seroma. Most seromas are small and resorb spontane- approximately 30 mCi. Those who are considered to be at high
ously; for some, aspiration is necessary. risk should receive approximately 100 to 150 mCi. Long-term
7. Keloid. Keloid formation after thyroidectomy is most (20-year) mortality is about 4% in low-risk patients and about
common in African-American patients and in patients with 40% in high-risk patients. Serum thyroglobulin levels should be
a history of keloids. determined before and after discontinuance of thyroid hormone;
07/08

8. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 8
such levels are very sensitive indicators of persistent thyroid tracheoesophageal groove, but care must be taken to not
disease after total thyroidectomy. injure the recurrent laryngeal nerve, which is frequently
encountered early in the course of the dissection. Upon
lateral retraction of the jugular vein and the carotid sheath
Parathyroidectomy and medial retraction of the strap muscles, the recurrent
operative planning laryngeal nerve can usually be identified when the tracheo-
esophageal groove is exposed.
The preparation for parathyroidectomy is similar to that for
thyroidectomy. Patients who have profound hypercalcemia Step 2 : Parathyroid Exploration and Resection Ex-
(serum calcium g12.5 mg/dL) or mild to moderate renal ploration for the parathyroid adenoma is undertaken on the
failure should be vigorously hydrated and given furosemide basis of the results of the preoperative localization studies.
if needed before operation. On rare occasions, patients with The upper parathyroid glands are usually found at the level
refractory hypercalcemia will require additional treatment with of the ligament of Berry, posterior to the recurrent laryngeal
bisphosphonates or calcitonin. Any electrolyte abnormalities nerve. The lower glands are usually found anterior to the
(e.g., hypokalemia) should be corrected. recurrent laryngeal nerve and caudal to the point where the
The gold standard operation for primary hyperparathyroidism recurrent laryngeal nerve crosses the inferior thyroid artery.
remains bilateral neck exploration; however, the excellent The thyroid gland can be retracted medially and anteriorly
results of preoperative imaging with sestamibi scanning and with a peanut sponge. Palpation for the adenoma may be
ultrasonography, coupled with the availability of rapid intra- carried out to complement visual inspection. Once the ade-
operative PTH assays, have made unilateral focused exploration noma is identified and carefully dissected free of surrounding
feasible for well-localized parathyroid adenomas. Preoperative tissues, its vascular pedicle is clipped and the specimen exam-
localizing studies are essential when reoperation for persistent or ined ex vivo. If intraoperative PTH monitoring is employed,
recurrent hyperparathyroidism is indicated. We do not believe postexcision values are obtained 5 and 10 minutes after spec-
that using the gamma probe is any better than preoperative imen removal and compared with preexcision values. At this
sestamibi scanning for either first-time surgery or reoperation. point, the remaining parathyroid gland on the ipsilateral side
All patients requiring reoperation should undergo direct or of the neck can be identified. If the intraoperative PTH level
indirect laryngoscopy before operation for evaluation of vocal does not drop by an appropriate amount, or if other intraop-
cord function. erative findings raise any questions regarding the diagnosis of
a single adenoma, then the contralateral side of the neck
operative technique should be explored.
Unilateral Exploration
Step 3: Closure The lateral border of the strap muscle
Step 1: Lateral Approach between Sternocleidomas- is approximated to the medial border of the sternocleidomas-
toid and Strap Muscles For a well-localized parathyroid toid muscle with one or two interrupted absorbable sutures.
adenoma, we usually perform unilateral exploration via a The platysma muscle is reapproximated with interrupted
lateral approach; this approach is also useful for reoperation. absorbable sutures, and the skin is closed with either buried
A 2 to 3 cm incision is made overlying a naturally occurring interrupted subdermal sutures or a continuous subcuticular
skin crease approximately 1 cm below the cricoid cartilage suture.
and lateral to the midline. The incision should overlie the
lateral border of the strap muscles and may extend onto the Bilateral Exploration
anterior surface of the sternocleidomastoid muscle for a dis- Steps 1 through 4 Steps 1, 2, 3, and 4 of a bilateral
tance of up to 0.5 cm. Dissection is continued down through exploration for parathyroidectomy are virtually identical to
the platysma muscle until the medial border of the sterno- steps 1, 2, 4, and 5 of a thyroidectomy [see Thyroidectomy,
cleidomastoid muscle is encountered. The medial border of Operative Technique, above], and the same troubleshooting
the sternocleidomastoid muscle is mobilized for a few centi- considerations apply.
meters superiorly and inferiorly. The avascular space between
the medial border of the sternocleidomastoid muscle and the Troubleshooting. About 85% of people have four parathy-
lateral border of the strap muscles is developed. The internal roid glands, and in about 85% of these persons, the parathyroids
jugular vein becomes apparent at this point. Deep and medial are situated on the posterior lateral capsule of the thyroid.
to this vein lies the carotid sheath. The internal jugular vein Normal parathyroid glands measure about 3x3x4 mm and are
and the carotid sheath are retracted laterally, and the lateral light brown in color. The upper parathyroid glands are more
border of the strap muscles is retracted medially. We do not posterior (i.e., dorsal) and more constant in position (at the level
routinely divide the omohyoid muscle, which will traverse the of the cricoid cartilage) than the lower parathyroid glands, which
space that is developed; the muscle can simply be retracted typically are more anteriorly placed (on the posterior-lateral
out of the path of the dissection. The recurrent laryngeal surface of the thyroid gland). In most patients, both the upper
nerve is frequently identified at this point within the tracheo- and the lower parathyroid glands are supplied by small branches
esophageal groove. The lateral border of the thyroid gland is of the inferior and superior thyroid arteries. About 15% of
identified, and the dissection of the parathyroid adenoma can parathyroid glands are situated within the thymus, and about
commence. 1% are intrathyroidal. Other abnormal sites for the parathyroid
glands are (1) the carotid sheath, (2) the anterior and posterior
Troubleshooting. The lateral approach affords easy mediastinum, and (3) anterior to the carotid bulb or along the
access to the lateral border of the thyroid gland and the pharynx (undescended parathyroids).
07/08

9. © 2008 BC Decker Inc ACS Surgery: Principles and Practice
2 HEAD AND NECK 9 THYROID AND PARATHYROID OPERATIONS — 9
The upper parathyroid glands are usually lateral to the have been located and no abnormal parathyroid tissue has
recurrent laryngeal nerve at the level of Berry’s ligament; their been identified. The carotid sheath and the area posterior
position makes them generally easier to preserve during thyroid- to the carotid, as well as the retroesophageal area, should
ectomy and easier to find during both parathyroid and thyroid also be explored. In rare cases, there may be an undescended
surgery. When the upper parathyroids are not found at this site, parathyroid tumor anterior to the carotid bulb.
they often can be found in the tracheoesophageal groove or in Although we do not recommend routine biopsy of more than
the posterior mediastinum along the esophagus. The lower para- one normal-appearing parathyroid gland, we do recommend
thyroid glands are almost always situated anterior to the recur- biopsy (not removal) and marking of all normal parathyroid
rent laryngeal nerves and caudal to the point where the recurrent glands that have been identified when no abnormal parathyroid
laryngeal nerve crosses the inferior thyroid artery; they may be tissue can be found. When four normal parathyroid glands
surrounded by lymph nodes. When the lower parathyroids are are found in the neck, the fifth (abnormal) parathyroid gland is
not found at this site, they usually can be found in the anterior usually in the mediastinum. Median sternotomy is not indicated
mediastinum (typically in the thymus or the thymic fat). during initial operation unless the patient’s calcium concentra-
tion is severely elevated; instead, the operation should be termi-
Step 5: Parathyroid Resection Abnormal parathyroid nated, the patient should undergo repeat imaging studies, and
glands are removed in the manner previously described referral to an endocrine surgery center should be considered.
(see above). In about 80% of patients with primary hyper- The surgeon’s responsibilities are to make sure during the
parathyroidism, one parathyroid gland is abnormal; in about initial operation that the elusive parathyroid adenoma is not
15%, all glands are abnormal (diffuse hyperplasia); and in removable through the cervical incision and to minimize
about 5%, two or three glands are abnormal and one or two complications. The risk of permanent hypoparathyroidism or
injury to the recurrent laryngeal nerve should be less than
normal. Parathyroid cancer occurs in about 1% of patients with
2%.
primary hyperparathyroidism. About 50% of patients with
parathyroid cancer have a palpable tumor, and most exhibit
Step 6: Closure Closure is essentially the same for
profound hypercalcemia (serum calcium g14.0 mg/dL).
parathyroidectomy as for thyroidectomy.
Troubleshooting. In some patients, parathyroid tumors complications
and hyperplastic parathyroid glands are difficult to find. If
The complications of parathyroidectomy are similar to
this is the case, the first step is to explore the sites where those of thyroidectomy but occur less often. Patients with a
parathyroids are usually located, near the posterolateral very high preoperative serum alkaline phosphatase level and
surface of the thyroid gland. (About 80% of parathyroid osteitis fibrosa cystica are prone to profound hypocalcemia
glands are situated within 1 cm of the point where the inferior after parathyroidectomy. In these patients, both serum
thyroid artery crosses the recurrent laryngeal nerve.) When a calcium and serum phosphorus levels are low. In contrast,
lower gland is missing from the usual location, it is likely to patients with true hypoparathyroidism exhibit low serum
be found in the thymus; this possibility can be confirmed by calcium levels but high serum phosphorus levels.
mobilizing the thymus from the anterior-superior mediasti-
num. If an upper parathyroid gland cannot be located, one outcome evaluation
should look not only far behind the thyroid gland superiorly Outcome considerations are essentially the same as for
but also in a paraesophageal position down into the posterior thyroidectomy. The patient should have a normal voice
mediastinum. A thyroid lobectomy or thyroidotomy can be and be normocalcemic. The overall complication rate and
done on the side where fewer than two parathyroid glands recurrence rate should be less than 2%.
Recommended Reading
Arici C, Cheah WK, Ituarte PH, et al. Can Clark OH. Endocrine surgery of the thyroid thyroidectomy. Surg Oncol Clin N Am
localization studies be used to direct focused and parathyroid glands. Philadelphia: WB 2008;17:121–44.
parathyroid operations? Surgery 2001;129: Saunders Co; 2003. Palazzo FF, Delbridge LW. Minimal-access/mini-
720–9. Lee JA, Inabnet WB 3rd. The surgeon’s arma- mally invasive parathyroidectomy for primary
Bliss RD, Gauger PG, Delbridge LW. Surgeon’s mentarium to the surgical treatment of hyperparathyroidism. Surg Clin North Am
approach to the thyroid gland: surgical primary hyperparathyroidism. J Surg Oncol 2004;84:717–34.
2005;89:130–5.
anatomy and the importance of technique.
Lennquist S. Thyroidectomy. In: Clark OH,
World J Surg 2000;24:891–7. Duh Q-Y, Kebebew E, editors. Textbook of
Cady B, Rossi R: Surgery of thyroid gland. endocrine surgery. 2nd ed. Philadelphia: WB
In: Cady B, Rossi R, editors. Surgery of the Acknowledgment
Saunders Co; 2005. p. 828.
thyroid and parathyroid glands. Philadelphia: Miller MC, Spiegel JR. Identification and moni-
WB Saunders Co; 1991. toring of the recurrent laryngeal nerve during Figures 1 through 7 Tom Moore.
07/08