Townsend Courtney M.Jr., Evers B. Mark. Atlas of General Surgical Techniques: Expert Consult

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CHAPTER 3 • Parathyroidectomy 45

2. DISSECTION

◆ A self-retaining retractor is used to retract the skin ﬂ aps. The dissection then proceeds

in the midline raphe, which provides a bloodless plane for the separation of the strap

muscles (Figure 3-6).

◆ As noted in Figure 3-7, the parathyroid adenoma has been localized preoperatively to the

right inferior location. In this situation the right inferior pole of the thyroid gland is identi-

ﬁ ed and this portion of the gland is gently mobilized.

FIGURE 3 –6

Right inferior pole

of thyroid gland

FIGURE 3 –7

46 Section I • Head and Neck and Endocrine Procedures

◆ The parathyroid adenoma is now mobilized, with care taken to preserve the recurrent laryngeal

nerve and minimize manipulation of the tumor during ligation of the end artery (Figure 3-8).

◆ If the adenoma is adherent to the thyroid gland, a pledget of gauze is effective in gently

teasing the adenoma away from the thyroid (Figure 3-9).

◆ Once the parathyroid adenoma is mobilized, care is taken to ensure that the vascular

supply is isolated and secured with either clips or ties, and the gland is then completely

excised (Figure 3-10). If a unilateral exploration had been undertaken with preoperative

localization, then many endocrine surgeons will obtain a rapid parathyroid hormone (PTH)

assay to conﬁ rm the adequacy of resection.

Right inferior

thyroid gland

Right recurrent

laryngeal nerve

FIGURE 3 –8

FIGURE 3 –9

FIGURE 3 –10

CHAPTER 3 • Parathyroidectomy 47

◆ If the operation being performed was for parathyroid gland hyperplasia, then a total

parathyroidectomy would be performed with autotransplantation of a portion of one of

the glands into, most commonly, the forearm or the sternocleidomastoid muscle. The

gland to be transplanted is minced into 1-mm pieces, and 12 to 18 pieces are embedded

in well-vascularized muscle and marked with a stitch or clip (Figure 3-11).

To laboratory

Minced

parathyroid gland

Staples in

brachioradialis

muscle

Interrupted

sutures

FIGURE 3 –11

48 Section I • Head and Neck and Endocrine Procedures

3. CLOSING

◆ Once the procedure is completed and hemostasis is ensured, closure is performed by ﬁ rst

reapproximating the strap muscles at the midline using interrupted 3-0 Vicryl sutures

(Figure 3-12).

◆ The platysma muscle is likewise reapproximated using interrupted 3-0 Vicryl sutures

(Figure 3-13).

◆ Finally, the skin is reapproximated with a subcuticular stitch of 4-0 Monocryl suture

(Figure 3-14).

STEP 4: POSTOPERATIVE CARE

◆ Operative complications are similar to those of thyroid surgery and include injury to the

recurrent laryngeal nerve, hematoma, and wound infection. The risk for these complica-

tions is theoretically less when exploration is conﬁ ned to one side of the neck.

◆ Most patients undergoing a minimally invasive parathyroidectomy are discharged on the

day of surgery. They are monitored carefully as outpatients, and serum calcium and intact

PTH levels are measured within the ﬁ rst week of follow-up.

STEP 5: PEARLS AND PITFALLS

◆ With better radiographic localization techniques, many endocrine surgeons are opting to

perform preoperative localization combined with intraoperative PTH assessment in the

management of patients with parathyroid adenomas. Rather than using general anesthesia,

some surgeons are advocating cervical blocks, which can be performed by the surgeon

before the procedure.

Interrupted

sutures

FIGURE 3 –12

Platysma muscle

FIGURE 3 –13

Subcuticular sutures

FIGURE 3 –14

CHAPTER 3 • Parathyroidectomy 49

50 Section I • Head and Neck and Endocrine Procedures

SELECTED REFERENCES

1. Akerström G, Malmaeus J, Bergström R: Surgical anatomy of human parathyroid glands. Surgery

1984;95:14-21.

2. Bilezikian JP, Potts JT Jr, Fuleihan EH, et al: Summary statement from a workshop on asymptomatic

primary hyperparathyroidism: A perspective for the 21st century. J Clin Endocrinol Metab 2002;87:

5353-5361.

3. Boggs JE, Irvin GL, Molinari AS, et al: Intraoperative parathyroid hormone monitoring as an adjunct to

parathyroidectomy. Surgery 1996;120:954-958.

4. Roman SA, Sosa JA, Mayes L, et al: Parathyroidectomy improves neurocognitive deﬁ cits in patients with

primary hyperparathyroidism. Surgery 2005;138:1121-1128.

5. Udelsman R, Donovan P: Remedial parathyroid surgery: Changing trends in 130 consecutive cases.

Ann Surg 2006;243:471-479.

STEP 1: SURGICAL ANATOMY

◆ Identiﬁ cation and preservation of the facial nerve and its branches is key to successful

parotid surgery.

◆ The anatomic landmarks that are used include the following (Figure 4-1):

◆ The mastoid process with the insertion of the sternocleidomastoid (SCM) muscle

◆ Posterior belly of the digastric muscle

◆ Tragal pointer

◆ Temporoparotid fascia

◆ Tympanomastoid ﬁ ssure

◆ Styloid process

◆ The parotid gland is anatomically composed of one lobe with an accessory lobe along

Stensen’s duct. The plane of the facial nerve divides the gland into lateral and deep lobes

for surgical purposes.

◆ The deep lobe is located along the posterior border of the ascending mandibular ramus or

adjacent to the masseter muscle along the ramus.

STEP 2: PREOPERATIVE CONSIDERATIONS

◆ Patients with parotid masses commonly present with painless, slowly enlarging preauricular

or upper cervical masses.

◆ Deep lobe masses may appear as lateral oropharyngeal masses.

◆ Tail of parotid masses can be mistaken for a cervical node.

◆ Facial nerve paresis/paralysis, pain, rapid growth, ﬁ rm mass, presence of multiple

paraglandular and upper cervical palpable lymph nodes, lack of mobility, and skin

involvement are suggestive of malignancy.

◆ Most parotid tumors are located in the tail (80%), and 80% of all parotid tumors are benign

(pleomorphic adenoma most common type).

CHAPTER

Parotidectomy

Anna M. Pou and Colin D. Pero

52 Section I • Head and Neck and Endocrine Procedures

◆ If malignancy or deep lobe involvement is suspected, imaging should be obtained.

◆ Fine needle aspiration is 94% sensitive, 97% speciﬁ c, and 95% accurate in diagnosis of

parotid masses. Inconclusive lymphoid cells do not exclude lymphoma. Fine needle aspi-

ration is useful for preoperative counseling.

◆ Open biopsy is not recommended because of the risk of implantation of malignant cells and

possible injury to the facial nerve. Open biopsy is indicated when malignancy is suspected

(facial nerve paralysis, skin involvement) and diagnosis cannot be conﬁ rmed with ﬁ ne

needle aspiration.

◆ If tumor is believed to be malignant, preoperative counseling should include possible facial

nerve sacriﬁ ce, neck dissection, reconstruction of the facial nerve, and possible facial reani-

mation surgery.

◆ Indications for lateral lobectomy include the following:

◆ Benign or malignant tumor (exceptions include benign lymphoepithelial cysts and

parotid lymphoma)

◆ Refractory sialolithiasis, sialoadenitis (chronic parotitis), and chronic sialorrhea; some

authors advocate total parotidectomy for chronic parotitis

◆ As part of lymph node dissection for other head and neck primary tumors, primarily

cutaneous malignancies of the face and scalp

◆ Excision of ﬁ rst branchial cleft cyst involving parotid gland

◆ Although superﬁ cial parotidectomy is performed for tumors located in the lateral lobe of

the parotid, most authors now recommend excision of the tumor with a healthy cuff of

normal gland, particularly if the tumor is located in the tail.

◆ Enucleation of benign tumors is to be condemned. This increases risk of facial nerve injury,

unacceptable risk of tumor recurrence, and increased difﬁ culty of facial nerve preservation

with repeat excision.

◆ Total parotidectomy with facial nerve preservation is indicated for tumors arising from or

extending to a plane deep to the facial nerve and for all medium- to high-grade malignant

tumors, regardless of location.

◆ Radical parotidectomy (total parotidectomy with facial nerve sacriﬁ ce) is indicated in cases

of malignant involvement of the main trunk of the facial nerve.

External jugular vein

2005 M Cooley

Hyoid bone

Thyroid cartilage

Sternocleidomastoid muscle

Modified Blair incision

Great auricular nerve

FIGURE 4 –1

CHAPTER 4 • Parotidectomy

54 Section I • Head and Neck and Endocrine Procedures

STEP 3: OPERATIVE STEPS

1. INCISION

◆ General endotracheal anesthesia without the use of muscle relaxants is preferred so that

facial nerve function can be monitored during the surgery.

◆ The patient is placed supine, with the head at the top of the table and the ipsilateral

shoulder as close to the edge of the operating table as possible. A shoulder roll is used to

extend the neck, and the head is supported with a foam rubber doughnut-shaped ring.

◆ The ear, neck, parotid gland, corner of mouth, and corner of eye are exposed so that facial

nerve function can be monitored. The cornea of the exposed eye is protected by suturing the

eyelid shut using 6-0 silk suture. A small Tegaderm dressing can be used in lieu of this stitch.

◆ A modiﬁ ed Blair incision (standard parotidectomy incision) is outlined using a sterile

marking pen. The incision is made in a relaxed preauricular skin crease, curves around the

lobule toward the mastoid tip and then anteriorly along a natural skin crease, curving

approximately 2 ﬁ ngerbreadths below the angle of mandible (see Figure 4-1). The skin

incision inferiorly remains supraplatysmal to prevent injury to the peripheral nerve

branches. The only visible portion of the skin incision after healing occurs is along the

upper neck incision. If a neck dissection or mastoidectomy is required for malignant

tumors, the incision must be modiﬁ ed accordingly.

◆ The anterior skin ﬂ ap is raised sharply in a supraplatysmal plane, above the parotid fascia,

to the anterior border of gland. The subcutaneous fat is elevated with the skin ﬂ ap. The

posterior skin ﬂ ap is then elevated, exposing the anterior border of the SCM muscle and the

mastoid process (Figure 4-2). Not shown here, the lobule is retracted posteriorly using a

2-0 silk suture to visualize the mastoid tip and cartilaginous ear canal.

Parotid fascia

FIGURE 4 –2