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Fig. 48.5 Identication of the RLN at the crico-tracheal joint
R. Simó et al.
Fig. 48.6 Identication of the RLN laterally at the level of the Tubercle of Zuckerkandl
the thyroid gland rst is systematically dissected, and its
contour is followed down to the position of the superior
parathyroid gland. Dissection is performed close to the capsule or pseudo-capsule to avoid unintentional removal of the
glands. The thyroid gland is inspected before its nal
removal to ensure that there are no parathyroid glands in the
main specimen. In the event of an inadvertent removal, part
of the gland is sent for frozen section, cut in small fragments
and auto-transplanted in the ipsilateral sternocleidomastoid
muscle pocket, which is then marked with ligaclips®. All
total or completion thyroidectomies for ITGs should treated
as high risk for hypocalcaemia and therefore should be
given calcium as well as 1 alfa calcidol as prophylaxis
(Fig.48.7).
48.7.1.8 Management ofBerry’s Ligament
Once the dissection reaches the Berry’s ligament, minimal
traction is applied when holding the thyroid lobe to avoid
traction injury to the nerve. The ligament is dissected from
the nerve with ne instruments, usually with judicious usage
of bipolar diathermy and ne scalpel dissection [17].
Closure
Wound Wash. Once the thyroidectomy is completed, the
wound is washed with water or normal saline.
Haemostasis. Haemostasis is essential. To check for any
bleeding points, the wound must be clean of clots. Once this
has been completed, a Valsalva manoeuvre should be used at
least twice to check.
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Fig. 48.7 Identication of the RLN inferiorly at the level of Beahr’s Triangle
Check that RLN’s and Parathyroid Glands. Once haemostasis is complete, the recurrent laryngeal nerves and the
parathyroid glands should be checked to ensure that they are
intact anatomically. If neuromonitoring is used, an EMG signal should be obtained and recorded.
Drainage. Suction drains, particularly when a signicant
dissection has resulted in a large dead space, or the patient
uses anticoagulation are encouraged. The presence of a drain
does not prevent hematoma, and an empty drain bottle is not
evidence that there is no bleeding. The need for drains should
be considered on an individual patient basis.
Subcutaneous Tissues and Skin Closure. The wound is
closed in layers. The strap muscles should be approximated
with an absorbable suture. The platysma should then be reapproximated using an absorbable suture. The skin should
then be closed with meticulous attention to detail, as this
should serve as the only evidence that these patients have
undergone surgery. The technique is less important than the
Fig. 48.8 Clinical photograph demonstrating the T-cervico-thoracic
incision and the subplatysmal aps in the neck
need to be precise and treat the skin edges with respect. The
ideal closure will allow easy re-opening in the event of
haematoma.
48.7.2.2 Cervical Stage
As per cervical approach.
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48.7.2 Extra-Cervical Approaches (ECA)
48.7.2.1 Combined Cervical andMidline
Sternotomy Approach
This approach was composed of three main stages
1. Cervical stage
2. Sternotomy and mediastinal stage
3. Thoracic inlet stage
48.7.2.3 Sternotomy andMediastinal
Dissection
The chest is completely exposed and prepared from neck to
umbilicus and areola mammae to areola mammae. A midline
incision is made from the cervical wound to xiphisternum in
T fashion (Fig.48.8). The subcutaneous fat is incised down
to the periostieum with cautery or scalpel. At this point, the
midline is identied superiorly at the sternal notch, inferiorly
at the xiphisternum and at a midpoint by digital palpation of
the rib spaces on each side. A linear incision in the sternal
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periosteum from top to bottom is then made with electrocauthery precisely in the midline in preparation for the saw. The
xiphisternum is cut with curved Mayo scissors and the suprasternal ligament with electrocautery. Blunt dissection with a
nger sweep retrosternally is then performed at the top and
bottom to visualise the path of the saw and prepare a space
for its path. The anaesthetist is instructed to stop ventilation
while the sternum is split with the saw. Once the sternotomy
is completed, ventilation is resumed and the bleeding from
the periosteal edges controlled with electrocautery, and the
Holmes-Sellars retractor is placed to expose the mediastinum. The mediastinum is inspected to identify and clarify
the extent and location of the goitre. The brachiocephalic or
innominate vessels are identied and controlled with soft
rubber vascular slings if necessary. Care is taken to minimise
unnecessary pleural or pericardial breach especially if malignancy is suspected. In these cases, it is preferred to start the
dissection as caudally as possible to clear out mediastinal fat
containing lymph nodes. Once the goitre is identied and the
mediastinal vessels controlled, the dissection is commenced
in the extracapsular plane anteriorly to inferiorly ligating any
extracapsular vessels that are encountered. The dissection
proceeds posteriorly and laterally delivering the specimen in
an upward direction until the thoracic inlet is reached
(Fig.48.9). At this point, the cavity was inspected for haemostasis and to ensure that no mediastinal structures have inadvertently injured [20].
of the RLN, which is carefully dissected from the reminding
thyroid gland (Fig.48.10) [20].
48.7.2.5 Closure
The cervical wound is closed as per the cervical approach.
The same principles of wound washing and haemostasis are
applied in the chest. Underwater size 28 drains are inserted,
and these will drain the neck and mediastinum, and a second
one is inserted if the pleura has been opened.
Titanium wires are used to close the sternum. The number
of wires will be dependent on the weight and height of the
patient. The subcutaneous tissues and skin are closed in a
similar fashion than in the neck.
48.7.3 Combined Cervical andLateral
Thoracotomy Approach
This approach was indicated when the goitre had grown into
the posterior mediastinum and reached the posterior pleura.
In these cases, it was considered that a midline sternotomy
would not offer enough space to dissect the goitre from its
posterior position. This approach was performed in two main
stages:
1. Cervical stage
2. Thoracotomy and intrathoracic and mediastinal stage
48.7.2.4 Thoracic Inlet Stage
Once the thyroid gland has been mobilised superiorly and
inferiorly, then the dissection is commenced to mobilise the
gland at the thoracic inlet. This is the narrowest part of the
dissection and by doing this at the end allows superior mobilisation of the gland. This also allows improved visualisation
48.7.3.1 Cervical Stage
The cervical stage follows the same approach as described
above. The thyroid lobe was dissected from its cervical
attachments (oesophagus and trachea) into the thoracic inlet
as much as possible, and it was free from the upper medias-
Fig. 48.9 Mobilisation of the goitre inferiorly from its mediastinal bed
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Fig. 48.10 Mobilisation of the thyroid gland at the level of the thoracic inlet with the exposure of the RLN being checked with the IONM probe
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tinal attachments. At this point, the cervical portion of the
thyroid lobe was amputated using harmonic scalpel, and the
This follows the same principles described above.
tissue between the recurrent nerve and the intrathoracic portion of the goitre was packed with two or three layers of
Surgicel ®Fibrillar absorbable haemostat. This was done to
facilitate the identication of the RLN and protect it during
the nal stages of the thoracotomy approach.
48.7.3.4 Post-operative Care
Patients with transcervical approaches should be nursed and
monitored in a dedicated surgical or head and neck ward.
Patients undergoing ECA should be nursed and monitored in the intensive care unit for 24h and then transferred
48.7.3.2 Thoracotomy andPosterior
to a dedicated surgical ward once stable.
Mediastinal Dissection Stage
The patient is re-positioned laterally but rolled back to
allow access to the anterior neck simultaneously with the
thoracotomy as needed. A high postero-lateral thoracotomy is made, usually through the right chest, as from the
left the aortic arch and its branches impede access. The
latissimus dorsi is divided, the serratus anterior muscle
preserved and the chest entered through the fourth interspace. It is usually necessary to separate the goitre from
the superior vena cava anteriorly, taking care not to injure
the phrenic nerve, and from the trachea. Special care was
taken not to injure the right RLN as is recurs around the
great vessels at the thoracic inlet. By dividing Sibson’s fascia, it is possible to join the thoracic with the cervical
planes of dissection. Lower down, the innominate vein was
often stretched across the goitre, and in mobilising it, care
should be taken not to tear this, or to avulse the feeding
veins from the goitre. Mobilisation of the goitre was best
achieved by blunt dissection within the capsule. Any
bleeding from the vascularised surface of the goitre is controlled by gauze packing during the dissection. A surface
cautery device such as the Aquamantys is used as a haemostatic adjunct [20].
Special consideration should be given to the
following
1. Post Extubation Airway Obstruction
In the case of bilateral surgery with both recurrent
laryngeal nerves at risk, transient or permanent bilateral
paralysis may cause life-threatening airway obstruction.
This may not always be evident upon immediate extubation, but should be suspected in a patient with stridor and
respiratory compromise following total thyroidectomy, or
a unilateral procedure on the background of co-existing
contralateral RLN palsy. If the patient is stable enough for
exible laryngoscopy, this will conrm the diagnosis.
Management depends on the degree of respiratory compromise and the level of condence in the nature of RLN
paralysis, that is, transient versus permanent. This is where
neuromonitoring is useful, as a nerve for which an intact
monitoring circuit had been conrmed with pre and post
dissection vagal stimulation should invariably recover
function [21]. Depending on the situation, a decision may
be made to closely monitor the patient with conservative
airway measures (e.g. supplemental oxygen, adrenaline
nebulisers) versus reintubation or tracheostomy.
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2. Bleeding
Post-operative bleeding may manifest as increased
drain output (e.g. over 100 mL in <1h) or an expanding
neck haematoma without any obvious increase in drain
output. Both situations require immediate neck reexploration and arrest of haemorrhage to avoid both airway and cardiovascular compromise.
3. Calcium Management
Calcium levels and post-operative hypoparathyroid-
ism need to be avoided in order to prevent cardiovascular
and neurological complications from hypocalcaemia.
After total thyroidectomy, the calcium and PTH levels
should be checked and the postoperative hypocalcaemia
protocol applied accordingly.
4. Post-operative Vocal Cord Function
Voice changes are common following thyroid surgery.
These are often caused by oedema of the larynx due to the
placement of the endotracheal tube during surgery, postsurgical venous congestion of the larynx and not necessarily by injury to the RLN.
The main reason for postoperative evaluation as
already stated is accurate visualisation of the vocal cords
and their function and therefore provides the measurement of one of the main outcomes of the surgery. Postoperative evaluation also provides functional information
that allows accurate correlation with the interpretation of
the EMG during neuromonitoring of the RLN. Finally,
recurrent laryngeal nerve palsy has implications for safety
of swallowing and of future contralateral surgery.
Recent reliable guidance suggests a more proactive
approach recommending pre- and post-operative evaluation of RLN function in all thyroid and parathyroid surgery procedures [22].
5. Thyroid Function
Following total or completion thyroidectomy, post-
operative thyroid hormone replacement is required. This is
usually in the form of oral levothyroxine, with doses adjusted
over a 2–8 weeks in order to achieve optimum levels of
serum thyroxine for individual patients. Following hemithyroidectomy, there is a 12–35% risk of hypothyroidism [23,
24]; hence, patients should have their thyroid function
assessed within 6–8weeks post surgery. Risk factors predictive of hypothyroidism following unilateral thyroid lobectomy include high normal serum TSH levels, lower free
thyroxine levels and Hashimoto’s thyroiditis [25, 26].
References
1. White ML, Doherty GM, Gauger PG.Evidence-based surgical management of substernal goiter. World J Surg. 2008;32(7):1285–300.
2. Randolph GW, Shin JJ, Grillo HC, etal. The surgical management
of goitre: part II. Surgical treatment and results. Laryngoscope.
2011;121(1):68–76.
3. Nixon IJ, Simo R. The neoplastic goitre. Curr Opin Otolaryngol
Head Neck Surg. 2013;21(2):143–9.
4. Landerholm K, Jarhult J.Should asymptomatic retrosternal goitre
be left untreated? A prospective single-centre study. Scand J Surg.
2015;104(2):92–5.
5. Dempsey GA, Snell JA, Coathup R, Jones TM.Anaesthesia for
massive retrosternal thyroidectomy in a tertiary referral centre. Br J
Anaesth. 2013;111(4):594–9.
6. Chiang FY, Lu IC, Chen HC, etal. Intraoperative neuromonitoring
for early localization and identication of recurrent laryngeal nerve
during thyroid surgery. Kaohsiung J Med Sci. 2010;26(12):633–9.
7. Findlay JM, Sadler GP, Bridge H, Mihai R. Post-thyroidectomy
tracheomalacia: minimal risk despite signicant tracheal compression. Br J Anaesth. 2011;106(6):903–6.
8. Randolph GW, Kobler JB, Wilkins J. Recurrent laryngeal nerve
identication and assessment during thyroid surgery: laryngeal palpation. World J Surg. 2004;28(8):755–60.
9. Lorente-Poch L, Sancho JJ, Ruiz S, Sitges-Serra A.Importance of
in situ preservation of parathyroid glands during total thyroidectomy. Br J Surg. 2015;102(4):359–67.
10. Huins CT, Georgalas C, Mehrzad H, Tolley NS.A new classication system for retrosternal goitre based on a systematic review of
its complications and management. Int J Surg. 2008;6(1):71–6.
11. McKenzie GA, Rook W.Is it possible to predict the need for sternotomy in patients undergoing thyroidectomy with retrosternal
extension? Interact Cardiovasc Thorac Surg. 2014;19(1):139–43.
12. Grainger J, Saravanappa N, D'Souza A, Wilcock D, Wilson PS.The
surgical approach to retrosternal goitres: the role of computerized
tomography. Otolaryngol Head Neck Surg. 2005;132(6):849–51.
13. Rios A, Sitges-Serra A.Surgical treatment of intrathoracic goitre.
Cirugia Esp. 2012;90(7):421–8.
14. Coskun A, Yildirim M, Erkan N.Substernal goitre: when is a sternotomy required? Int Surg. 2014;99(4):419–25.
15. Randolph G. Surgery of the thyroid and parathyroid glands.
Amsterdam: Elsevier; 2013.
16. Simo R, Nixon I, Tysome J, Balfour A, Jeannon JP. Modied
extended Kocher incision for total thyroidectomy with lateral compartment neck dissection—a critical appraisal of surgical access
and cosmesis in 31 patients. Clin Otolaryngol. 2012;37:395.
17. Bliss RD, Gauger PG, Delbridge LW. Surgeon’s approach to the
thyroid gland: surgical anatomy and the importance of technique.
World J Surg. 2000;24(8):891–7.
18. Darr EA, Randolph GW.Management of laryngeal nerves and parathyroid glands at thyroidectomy. Oral Oncol. 2013;49(7):665–70.
19. Hisham AN, Lukman MR. Recurrent laryngeal nerve in thyroid
surgery: a critical appraisal. ANZ J Surg. 2002;72(12):887–9.
20. Simo RNI, Ofo E. Surgery for intrathoracic goitre (retrosternal)
goitres. In: Fagan J, editor. Open access atlas of otolaryngology,
head and neck operative surgery. Cape Town: University of Cape
Town; 2015.
21. Randolph GW, Dralle H, Abdullah H, et al. Electrophysiologic
recurrent laryngeal nerve monitoring during thyroid and parathyroid surgery: international standards guideline statement.
Laryngoscope. 2011;121(Suppl 1):S1–16.
22. Chandrasekhar SS, Randolph GW, Seidman MD, etal. Clinical
practice guideline: improving voice outcomes after thyroid surgery.
Otolaryngol Head Neck Surg. 2013;148(6 Suppl):S1–37.
23. Piper HG, Bugis SP, Wilkins GE, Walker BA, Wiseman S, Baliski
CR. Detecting and dening hypothyroidism after hemithyroidectomy. Am J Surg. 2005;189(5):587–91.
24. McHenry CR, Slusarczyk SJ.Hypothyroidisim following hemithyroidectomy: incidence, risk factors, and management. Surgery.
2000;128(6):994–8.
25. Stoll SJ, Pitt SC, Liu J, Schaefer S, Sippel RS, Chen H.Thyroid
hormone replacement after thyroid lobectomy. Surgery.
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26. De Carlucci D Jr, Tavares MR, Obara MT, Martins LA, Hojaij FC,
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Part XIX
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Parathyroid Surgery
Bilateral Exploration
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Parathyroidectomy
F.FaustoPalazzo andAntonioSitges-Serra
49
49.1 Introduction
Despite improved localisation studies that have led to focused
parathyroid surgery, there is still a role for bilateral neck
exploration parathyroid surgery. This is required when multiple gland disease is highly probable either due to a genetic
predisposition, the presence of known secondary or tertiary
disease or when there is no clear localisation of the diseased
gland or glands. The objective is the visualisation of all four
parathyroid glands and removal of only those that are
diseased.
The objective of parathyroid surgery for primary hyperparathyroidism is to achieve long-term normocalcaemia and
normalisation of the patient’s serum parathyroid hormone
(PTH) level. In renal dialysis and in post-renal transplant
patients with severe secondary or tertiary hyperparathyroidism, the role of parathyroidectomy is to reduce the signicant serum PTH excess to an extent that is tailored to the
patient’s situation. Whatever the goals in parathyroid surgery, they should be achieved with minimal morbidity.
Successful parathyroid surgery requires the surgeon to be
aware of the numerous guises and distribution of normal and
pathological parathyroid glands and to have acquired the
technical skills required to safely remove abnormal glands
and preserve normal parathyroid glands and their function.
Nowhere is this more true than in modern open parathyroid
surgery. This chapter describes the standard bilateral exploration parathyroidectomy (BEP) for non-localised adenomas
or for suspected or conrmed multiglandular disease.
The most common indication for BEP is negative or discordant preoperative imaging studies. Negative parathyroid
F. F. Palazzo (*)
Department of Thyroid and Endocrine Surgery, Hammersmith
Hospital and Imperial College London, London, UK
e-mail: f.palazzo@imperial.ac.uk
A. Sitges-Serra
Department of Surgery, Hospital del Mar, Barcelona, Spain
e-mail: asitges@parcdesalutmar.cat; asitges@hospitaldelmar.cat
Tc-mibi scintigraphy and/or negative neck ultrasound may
occur in the presence of small adenomas, a deep posteriorly
placed parathyroid gland (particularly in superior glands),
and in the presence of concomitant thyroid nodular disease
[1–3].
Candidate multigland disease syndromes include secondary hyperparathyroidism in patients on haemodialysis,
hyperparathyroidism after renal transplantation, lithiuminduced hyperparathyroidism and the hereditary forms of
hyperparathyroidism, mainly familial isolated hyperparathyroidism and the MEN 1 and 2 syndromes [4].
Given that at least 5–10% of primary hyperparathyroidism cases are caused by multigland disease and localisation
is frequently negative because of the increasingly mild disease at diagnosis, the need for BEP is not uncommon and
likely to become more common in time. Furthermore, the
pendulum may have swung slightly away from low- threshold
selective parathyroid surgery because BEP can be performed
quickly through small incisions and may have a marginally
lower rate of persistence and recurrence [5].
49.2 Preoperative Checklist,
Considerations andAnaesthesia
Parathyroid surgery should be preceded by informed consent. It is important that the surgeon quanties the surgical
risks based on his or her own practice data. The failure to
cure the patient of hyperparathyroidism is likely to be the
most common adverse effect of surgery, which even in expert
hands will occur in 2–5% of cases. Other risks include voice
change, bleeding, infection, hypoparathyroidism and the
possible need for an associated thyroidectomy. Same-day
discharge may be discussed with those patients who meet the
criteria for major ambulatory surgery.
Co-existent thyroid nodular disease, usually benign, is
common in some countries where goitre is highly prevalent,
and partial or total thyroidectomy may need to be performed
© Springer Nature Switzerland AG 2024
R. Simo et al. (eds.), Atlas of Head and Neck Surgery, Springer Surgery Atlas Series,
https://doi.org/10.1007/978-3-031-36593-5_49
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F. F. Palazzo and A. Sitges-Serra
at the time of parathyroidectomy [6]. This possibility should
be assessed in the preoperative thyroid/parathyroid ultrasound and discussed with the patient. Eventually, full work up for thyroid disease (e.g. FNA, calcitonin, autoantibodies)
may be necessary.
BEP is usually performed under general anaesthesia but
also can be performed with local anaesthetic and sedation
and bilateral supercial cervical plexus anaesthesia, although
care is required due to the risk of bilateral phrenic nerve
paralysis. Antibiotic prophylaxis is not usually required
unless the patient has increased risk factors for post- operative
infection, such as immune suppression, renal failure, diabetes or particular constitutional frailty. Compression stockings are sufcient prophylaxis against deep venous
thrombosis in patients at risk, as the operation is usually brief
and early post-operative mobilisation is the norm. The patient
is supine or in Fowler’s position, with a mild degree of neck
extension. The skin incision can be marked to ensure the
placement of a symmetrical skin crease incision.
All imaging performed should be available for review
prior to surgery. Intraoperative PTH monitoring is not essential in BEP, since the aim to identify all parathyroid glands.
49.3 Indications
Regardless of the approach adopted, parathyroid surgery
requires an incontrovertible diagnosis of primary or tertiary
hyperparathyroidism. The clinical indications for BEP in primary hyperparathyroidism, either sporadic or familial, are
identical to those of targeted surgery and can be grossly summarised as patients of any age with symptoms or evidence of
end organ damage (osteoporosis, nephrolithiasis, hypercalcaemic syndrome, decreasing renal function), all patients
under the age of 50years regardless of symptoms, and probably most asymptomatic patients older than 50years who are
t for surgery, since there is no satisfactory alternative longterm medical treatment. Delaying surgery in asymptomatic
young patients with MEN1 may be advisable, owing to the
relatively high risk of recurrence even after appropriate initial surgical treatment (subtotal parathyroidectomy plus transcervical thymectomy being the preferred approach).
49.4 Surgical Strategy andTechnique
The key objective in a BEP is the visualisation of all four
parathyroid glands; doing so remains the most likely guarantee to a long-term cure of hyperparathyroidism. The surgery can be achieved via a 3- to 4-cm transverse cervicotomy
in all but patients with the highest body mass index or those
with a concomitant goitre. A thorough anatomical and
embryological understanding of the parathyroid glands,
which forms the basis of the surgical exploration, is essential [7].
• A standard transverse cervicotomy incision is placed
1–2cm below the cricoid cartilage, and the platysma is
divided with a blade or electrocautery. The avascular subplatysmal aps are raised supercial to the anterior jugular veins. The infrahyoidal muscles are separated on the
bloodless midline. Occasionally, some small vessels may
cross the midline, especially at and above the thyroid cartilage; these must be controlled.
• The rst step of BEP is not to look for the abnormal parathyroid gland, but rather to identify the key landmarks in
a bloodless eld. The sternohyoid and sternothyroid
muscles are mobilised off the underlying thyroid gland.
Division of the sternothyroid muscle’s upper insertion
may be required to properly mobilise the upper pole of
the thyroid lobe in patients with a short neck. The thyroid
lobe is then rotated medially off the major vessels
(Fig.49.1). This requires division of the middle thyroid
vein (which can be absent, small or multiple) to allow
full lateral mobilisation from the superior pole of the thyroid to the thyrothymic ligament’s lateral margin inferiorly. Care should be taken to isolate the thyrothymic
ligament anterolaterally from the sternohyoid muscle
and posteriorly from the level VI nodal compartment
(Fig.49.2). This step is key to not missing the inferior
parathyroid glands. The prevertebral fascia, the inferior
thyroid artery and the recurrent laryngeal nerve should
all be clearly identied. At this point, most parathyroid
glands are in view—especially those that are pathological (Fig.49.3).
• If the parathyroid glands are not immediately visible at
this point, then a systematic approach to each parathyroid
gland is required, following a predetermined plan that
may be modied according to the surgeon’s preference.
(The following is the authors’ preference.)
• Look for the superior parathyroid gland rst; it is more
constant in position and is the most rapidly identiable. If
this gland is normal, it provides the surgeon with the blueprint for how the normal parathyroid glands are likely to
look in this particular patient. Most superior parathyroid
glands are within a 1-cm radius of the cricothyroid joint
and close to the crossing of the inferior thyroid artery and
the recurrent laryngeal nerve. The superior parathyroid
glands are usually posterior to the recurrent laryngeal
nerve. The most common cause of non-visualisation of a
normal or an abnormal upper gland is a posterior para/
retroesophageal position. An uncommon intercricothyroidal gland may require division of the upper pole vessels
for proper identication (Fig.49.4a).
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Fig. 49.1 After retracting the infrahyoid muscles, the whole length of the external border of the thyroid lobe is freed to allow elevation and exposure of its dorsal surface
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Fig. 49.2 A left lower thymic parathyroid adenoma. Notice the clean separation between the medial border of the sternohyoid muscle and the
thyrothymic ligament
• The inferior parathyroid gland is typically situated caudal
to the inferior thyroid artery, anterior to the recurrent
laryngeal nerve and lateral to the midline. The most common causes of non-identication of an inferior gland are
a thyroid subcapsular at position or a low descent within
the thyrothymic ligament (Figs.49.2 and 49.4b).
• If all four glands are positively identied, the one or more
that are abnormal may be removed, leaving the normal,
well-vascularised and minimally disturbed glands in situ.
If all four are abnormal, a physiologically sized remnant
is fashioned rst prior to removing the other three glands.
The option of marking the remnant with a long, nonab-
sorbable suture may be considered in order to facilitate
reoperation in case of remnant hyperplasia, a potential
cause of recurrence in renal and MEN1 patients.
• When a standard exploration does not nd the pathological parathyroid gland(s), a dedicated search is now
required. Several sites require specic assessment:
– Para/retroesophageal descended superior gland in
close vicinity to the recurrent laryngeal nerve
(Fig.49.5)
– Medial to the superior thyroid pole (intercricothyroidal
position)
– Low thymic inferior gland
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Fig. 49.3 Exposure of the dorsal surface of the left thyroid lobe and identication of key anatomical landmarks to approach an upper parathyroid
adenoma
F. F. Palazzo and A. Sitges-Serra
a
b
Fig. 49.4 (a, b) A right lower parathyroid adenoma lying within neatly dissected thyrothymic ligament
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