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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_987_Библиотеки_им_академика_М_И_Перельмана.pdf
144
R. W. Randle
Parathyroidectomy Techniques
Choosing anOperative Approach
• Disease characteristics, suspicion for multi-gland disease, imaging ndings, and
surgeon preference are the main considerations in determining the operative
approach.
• Primary hyperparathyroidism is most commonly caused by a single abnormal
parathyroid gland or adenoma.
• Secondary and tertiary hyperparathyroidism as well as primary hyperparathy-
roidism associated with genetic predisposition (like Multiple Endocrine
Neoplasia 1) are generally best treated with bilateral exploration given the
increased likelihood of multigland disease.
• The simplied goals of parathyroidectomy for primary hyperparathyroidism are
two-fold:
– Remove diseased parathyroid tissue.
– Preserve normal parathyroid function.
Steps of Parathyroidectomy
• Following induction, place the patient supine or in a semi fowler position with
the neck extended.
• Establish the sterile eld and make a transverse incision between the cricoid
cartilage and the sternal notch, ideally within a natural skin crease for optimal
cosmesis.
• Divide the platysma transversely and raise superior and inferior subplatysmal
aps to improve exposure. The strap muscles are separated along the median
raphe to expose the thyroid and parathyroid tissues beneath.
• Blunt dissection lifts the strap muscles off the thyroid and separates the thyroid
from the carotid sheath facilitating exposure of the lateral and posterior borders
of the thyroid. Ligation of the middle thyroid vein can aid medialization of the
thyroid if necessary.
• Superior parathyroid glands are most often identied within the trachea-
esophageal groove, deep and lateral to the recurrent laryngeal nerve.
• Inferior glands are most often located at the same depth of the thyroid inferiorly
within the thyro-thymic ligament supercial and medial to the recurrent laryngeal nerve.
• Missing glands are most often in their normal orthotopic location.
• Ectopic superior parathyroid glands can be located behind the esophagus,
dropped into the mediastinum, or within the thyroid.
16 Parathyroidectomy: Techniques, Adjuncts, andPotential Complications
145
• Ectopic inferior glands can be in the thymus, along the carotid sheath, within the
thyroid, or undescended beneath the mandible.
• Following resection of the diseased gland or glands, intra-operative PTH can be
used to conrm a successful operation and ensure viable, vascularized parathyroid tissue remains.
• Hemostasis is achieved, the median raphe and platysma are reapproximated and
the skin is closed and dressed.
Minimally Invasive Parathyroidectomy
• Since a single adenoma causes primary hyperparathyroidism in over 80% of
patients, a minimally invasive, or focused, approach can minimize dissection and
reduce the risk of complications.
• A minimally invasive approach requires successful preoperative localization
(Fig.16.1) and often employs intraoperative parathyroid hormone monitoring to
conrm adequate resection when and where available.
• If intraoperative parathyroid hormone monitoring suggests additional disease
remains following the resection of a presumed single adenoma, conversion to a
bilateral neck exploration should be considered.
a
b
c
Fig. 16.1 Parathyroid imaging. Images from a 4D Parathyroid CT are depicted in the sagittal (a)
and axial (b) planes successfully localizing an ectopic left superior parathyroid adenoma behind
the esophagus not seen on ultrasound due to shadowing from the trachea. Image c shows the
resected specimen following a minimally invasive parathyroidectomy
146
R. W. Randle
Bilateral Neck Exploration
• A bilateral neck (or 4-gland) exploration is the classic approach to parathyroid-
ectomy and remains both safe and effective when performed by experienced
surgeons.
• In general, all four parathyroid glands are identied and abnormal or enlarged
glands are removed. If all glands appear abnormal, a subtotal parathyroidectomy
or total parathyroidectomy with parathyroid reimplantation can achieve a cure
and preserve parathyroid function.
• Secondary and tertiary hyperparathyroidism should be approached with a bilat-
eral neck exploration because these disease processes typically affect all parathyroid glands.
• Inability to localize a single adenoma with preoperative imaging and often dis-
cordant preoperative imaging should prompt a bilateral neck exploration.
Subtotal Parathyroidectomy
• Since most people have four parathyroid glands, a subtotal parathyroidectomy
involves removal of 3 or 3.5 parathyroid glands.
• Indicated for conditions where all parathyroid tissue is hyperfunctioning such as
in patients with secondary hyperparathyroidism, tertiary hyperparathyroidism,
or primary hyperparathyroidism caused by 4-gland hyperplasia.
• A subtotal parathyroidectomy requires a bilateral neck exploration.
Parathyroid Reimplantation
• Devitalized parathyroid tissue can be minced to increase surface area and
implanted into a small pocket created in the muscle (usually the sternocleidomastoid, sternohyoid, or brachioradialis).
• Reimplantation may be indicated following unplanned or inadvertent parathy-
roid devascularization or as a planned total parathyroidectomy with autotransplantation for secondary hyperparathyroidism or certain familial conditions
causing multigland parathyroid disease like multiple endocrine neoplasia.
Remote Access Parathyroidectomy
• Select patients with suspected single gland disease might be appropriate candi-
dates for remote access, video-assisted, or robotic parathyroidectomy.
16 Parathyroidectomy: Techniques, Adjuncts, andPotential Complications
• Remote access approaches include retroauricular, transaxillary, and transoral.
147
Reoperative Parathyroidectomy
• Indicated for symptomatic persistent or recurrent disease.
• Associated with a lower cure rate and higher complication rate than an initial
parathyroidectomy.
• Many surgeons prefer localization of abnormal parathyroid tissue with two con-
cordant imaging modalities prior to reoperation.
Operative Adjuncts
• Operative adjuncts are helpful to determine the success of the operation, conrm
resected parathyroid tissue as well as aid localization, and improve visualization
of parathyroid glands in situ.
• While helpful, these adjuncts cannot substitute for surgeon experience nor
replace the need for sound clinical judgment.
Parathyroid Hormone Monitoring
• Most common operative adjunct used to determine the success of parathyroidec-
tomy while the patient remains under anesthesia.
• According to the Miami Criterion, surgeons should draw intra-operative PTH
levels prior to incision (baseline), just prior to excision of the abnormal parathyroid gland, 5min following excision, and 10min following excision. A decrease
of at least 50% of the highest level drawn before excision suggests adequate
removal of all hyperfunctioning parathyroid tissue [3].
• The Miami Criterion and variations are commonly used to help determine suc-
cessful excision of all abnormal parathyroid tissue during parathyroidectomy
(Table16.1) [4, 5].
• Measuring parathyroid hormone levels simultaneously from both internal jugu-
lar veins low in the neck can help aid disease localization intra-operatively.
Frozen Section
• Involves an intra-operative parathyroid biopsy with real-time pathology
assessment.
148
Table 16.1 Select intra-operative parathyroid hormone monitoring protocols [5, 11]
PPV
Criteria for success
Miami criterion (at least 50% decrease in PTH level 10min
post-excision compared with the highest of the baseline or
pre-excision PTH levels)
Vienna criterion (at least 50% decrease in PTH level 10min
post-excision compared to pre-incision level)
Rome criterion (at least 50% decrease in PTH level and/or into
the normal range 20min post-excision compared with the highest
of the baseline or pre-excision PTH levels and/or a 20-min level
at least 7.5ng/L less than the 10-min level)
A modied Miami criterion (at least a 50% decrease in PTH
level 10minutes post-excision and into the normal PTH range)
Halle criterion (PTH levels <35ng/L 15min post excision) 100 14 65
(%)
99–100 70–88 97
99–100 56–61 86–92
100 26.3 83.8
99 42 79
R. W. Randle
NPV
(%)
Accuracy
(%)
• Can help conrm parathyroid tissue with nearly 99% accuracy [6].
• Cannot denitively identify whether or not a parathyroid gland is
hyperfunctioning.
Parathyroid Aspiration
• Involves aspiration of a suspected parathyroid gland, mixing the aspirate with
2cc saline, and running the PTH assay.
• Can differentiate parathyroid tissue from thyroid, nodal, and fatty tissue and
eliminate the need for biopsy and frozen section [7].
Radioguidance
• Involves the administration of Tc-99m Sestamibi prior to parathyroidectomy and
measurement of radioactivity using a gamma probe intra-operatively (Fig.16.2).
• Since both thyroid and parathyroid tissue take up Sestamibi a ratio between the
two is obtained.
– A background level is measured over the thyroid isthmus.
– Ex-vivo measurements are obtained placing the excised parathyroid on the
probe while pointing the probe away from the operative eld.
• Ex-vivo counts of the parathyroid >20% of the background suggest hyperplasia
while counts >50% of the background suggest an adenoma [8].
• Useful both for conrming parathyroid tissue and whether or not the gland is
hyperfunctioning.
16 Parathyroidectomy: Techniques, Adjuncts, andPotential Complications
Fig. 16.2 Radioguided
parathyroidectomy. A
gamma probe is used to
measure Tc-99m Sestamibi
activity during a
radioguided
parathyroidectomy
Gamma
Probe
149
• Can help direct targeted exploration by measuring relative counts in different
areas of the neck.
Fluorescence
• Parathyroid glands auto-uoresce under near-infrared light and can be differenti-
ated from thyroid tissue in situ but autouorescence cannot assess gland viability
because it is an intrinsic property of parathyroid tissue independent from perfusion [9].
• Intravenous administration of indocyanine green can highlight perfused parathy-
roid tissue which may play a role in determining the viability of remnant parathyroid tissue following a subtotal parathyroidectomy [9].
Cryopreservation
• Involves the use of anti-freezing solutions and very low temperatures which
arrest cellular processes that lead to cell death.
• Can be used to preserve excised parathyroid tissue for patients following subtotal
or reoperative parathyroidectomy when the surgeon is concerned about
hypoparathyroidism.
150
• Restoring parathyroid function using thawed, cryopreserved parathyroid tissue is
often unsuccessful [10].
R. W. Randle
Complications
• Parathyroidectomy is very safe and complications are rare.
• Cure rates are higher and complication rates are lower when performed by expe-
rienced, high-volume surgeons.
Persistence andRecurrence
• Cure from primary hyperparathyroidism is considered normal calcium homeo-
stasis for at least 6months following parathyroidectomy [1].
• Cure rates should reach over 95%.
• Persistent disease includes failed re-establishment of normal calcium homeosta-
sis within 6months of parathyroidectomy.
• Recurrence includes disease occurring beyond 6 months following
parathyroidectomy.
Hypocalcemia andHypoparathyroidism
• Temporary hypocalcemia is common after parathyroidectomy.
• Surgeons may consider temporary calcium supplementation with or without
vitamin D to improve calcium absorption in post-operative patients.
• Permanent hypoparathyroidism resulting from insufcient viable parathyroid
tissue after parathyroidectomy is rare occurring in 0–4% of cases [1, 2].
• Permanent hypoparathyroidism can occur after bilateral exploration or reopera-
tive parathyroidectomy.
• For patients with severe post-operative hypocalcemia or permanent hypopara-
thyroidism, the management includes calcium supplements and calcitriol.
Laryngeal Nerve Injury
• Nerve injuries are rare during parathyroidectomy.
• Injury to the recurrent laryngeal nerve causes xation of the ipsilateral vocal
cord in a paramedian position placing the patient at risk for a weak, breathy voice
and aspiration.
16 Parathyroidectomy: Techniques, Adjuncts, andPotential Complications
151
• Injury to the external branch of the superior laryngeal nerve can result in impaired
projection and decreased pitch.
Hematoma
• Cervical hematoma is a rare but life-threatening complication of
parathyroidectomy.
• Patients should be monitored for the development of a cervical hematoma and a
compressive hematoma should be evacuated.
Infection
• Parathyroidectomy is a clean case and the neck has excellent blood ow making
infection following parathyroidectomy very rare.
Conclusions
Parathyroidectomy is an effective treatment for parathyroid disease and is safe in
experienced hands. Numerous operative approaches exist and should be tailored in
each patient to the specic disease characteristics, imaging ndings, and surgeon
preference. Regardless of the chosen approach, operative adjuncts that aim to maximize the chance of cure and minimize surgical risk are available but none can
replace sound clinical judgment and surgeon experience.
References
1. Wilhelm SM, Wang TS, Ruan DT, etal. The American Association of Endocrine Surgeons
guidelines for denitive management of primary hyperparathyroidism. JAMA Surg.
2016;151:959.
2. Udelsman R, Åkerström G, Biagini C, Duh Q-Y, Miccoli P, Niederle B, Tonelli F.The surgical
management of asymptomatic primary hyperparathyroidism: proceedings of the fourth international workshop. J Clin Endocrinol Metabol. 2014;99:3595–606.
3. Khan ZF, Lew JI.Intraoperative parathyroid hormone monitoring in the surgical management
of sporadic primary hyperparathyroidism. Endocrinol Metab (Seoul). 2019;34:327–39.
4. Barczyński M, Konturek A, Stopa M, Nowak W. Nodal recurrence in the lateral neck after
total thyroidectomy with prophylactic central neck dissection for papillary thyroid cancer.
Langenbeck’s Arch Surg. 2014;399:237–44.
152
5. Carneiro DM, Solorzano CC, Nader MC, Ramirez M, Irvin GL.Comparison of intraoperative
iPTH assay (QPTH) criteria in guiding parathyroidectomy: which criterion is the most accurate? Surgery. 2003;134:973–9. discussion 979-981
6. Westra WH, Pritchett DD, Udelsman R.Intraoperative conrmation of parathyroid tissue during parathyroid exploration: a retrospective evaluation of the frozen section. Am J Surg Pathol.
1998;22:538–44.
7. Perrier ND, Ituarte P, Kikuchi S, Siperstein AE, Duh QY, Clark OH, Gielow R, Hamill
T.Intraoperative parathyroid aspiration and parathyroid hormone assay as an alternative to
frozen section for tissue identication. World J Surg. 2000;24:1319–22.
8. Chen H, Mack E, Starling JR.Radioguided parathyroidectomy is equally effective for both
adenomatous and hyperplastic glands. Ann Surg. 2003;238:332–7. discussion 337-338
9. Graves CE, Duh Q-Y.Fluorescent technologies for intraoperative parathyroid identication.
Ann Thyroid. 2020;5:1–12.
10. Shepet K, Alhefdhi A, Usedom R, Sippel R, Chen H.Parathyroid cryopreservation after parathyroidectomy: a worthwhile practice? Ann Surg Oncol. 2013;20:2256–60.
11. Barczynski M, Konturek A, Hubalewska-Dydejczyk A, Cichon S, Nowak W. Evaluation of
Halle, Miami, Rome, and Vienna intraoperative iPTH assay criteria in guiding minimally invasive parathyroidectomy. Langenbeck’s Arch Surg. 2009;394:843–9.
R. W. Randle
Part III
Adrenal