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M. Sakr
including compressive symptoms, hoarseness, dysphagia, and importantly, cancer [32, 33], the incidence of which approaches that of patients with a
solitary thyroid nodule (STN) [34].
12.2.2 Pathogenesis
Pathogenesis of MNG mainly describes two concepts; the I2-deciency goiters (endemic goiters)
and the non-I2-deciency goiters (sporadic goiters)
[35]. In I2 deciency, less thyroid hormones are produced. A feedback mechanism leads to increased
TSH production and consequently to proliferation
of thyroid follicles [27] resulting in hypertrophy and
hyperplasia of the thyroid gland in a diffuse and
homogenous manner [36]. In contrast, in nodular
goiter, nodules are surrounded by normal and connective tissue suggesting that they result from heterogeneity of growth [35]. Autonomous growth
may occur in toxic and in euthyroid nodular goiter
depending on whether the gland produces excessive
amounts of hormones or not [37].
In general, the pathogenetic mechanisms of
goiter include iodine deciency, autonomy,
immunological thyropathy, thyroiditis, cyst formation, hematoma, trauma, tumors, neoplastic
production of TSH or TSH analog, acromegaly,
hormonal resistance, enzyme deciency, involvement of thyroid gland in extra-thyroid/systemic
diseases, and goitrogenic substances. Other possible factors leading to the development of nodules, even in the absence of I
deciency, are the
2
epidermal GF and the insulin-like GF [38].
For prophylaxis of endemic goiter in I2decient areas, supplementation with 150μgI2/
day is recommended for adults and is increased
in pregnancy to 200μg I2/day. This dose should
be adjusted for children to 50μg for the rst year
of life, 90μg for ages 1–6years, and 120μg for
ages 7–12years [39, 40].
12.2.3 Clinical Assessment
12.2.3.1 Patient’s History
The patient’s history may be without complaint
or may, apart from an awareness of the goiter
size, include a globus sensation, dysphagia, dys-
pnea, choking, or stridor. The rate of growth over
time as well as symptoms of hypo or hyperthyroidism must be evaluated. Symptoms of
hyperthyroidism include increased appetite,
weight loss, heat intolerance, nervousness, irritability, agitation, palpitation, diarrhea, muscular
weakness (myopathy) as well as oligo-/dysmenorrhea. On the other hand, the main symptoms of hypothyroidism are weight gain
(myxedema), depression, concentration weakness, cold intolerance, fatigue, constipation, and
oligo-/amenorrhea [39].
12.2.3.2 Physical Examination
Palpation of the thyroid gland is performed from
the back of the patient. Typically, it moves up
with deglutition. The size of the gland is evaluated, nodules are palpated (Fig. 12.2a–d), and
signs of local compression are assessed. Retrosternal goiter (RSG) may not be visible on clinical examination and may be unrecognized for
many years. It may cause superior vena caval
obstruction. Additionally, cervical LNs should be
examined for size, consistency, and mobility,
which may indicate malignancy.
Signs of “hyperthyroidism” may include
tachycardia, tachyarrhythmias (extra-systoles,
atrial brillation or utter), hyperreexia, ne
tremors, warm and moist hands, soft and ne hair
as well as hair loss. “Thyrotoxic crisis/coma” is a
severe condition of untreated exacerbated hyperthyroidism that may occur in Graves’ disease,
autonomous adenoma, or multinodular toxic goiter. It presents with tachycardia, tachyarrhythmia, hyperthermia, diarrhea, vomiting,
dehydration, muscular weakness, excitation
(grade 1), disorientation, hallucination, somnolence (grade 2), and coma (grade 3).
Signs of “hypothyroidism” include bradycardia, hypotension, cardiac insufciency, slow tendon reexes, dry, pale, cold, rough and doughy
skin (myxedema), rough hair, and a hoarse voice.
Myxedema coma frequently occurs after chronic
untreated hypothyroidism with acute exacerbation
due to infection, operation, severe general disease,
cold, or sedative. It presents with somnolence,
severe hypothermia, hypotension, bradycardia,
hypoventilation, hyponatremia, hypoglycemia,
and possible pericardial and pleural effusion.
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12 Benign Thyroid Disease
287
Fig. 12.2 (a) A 28-year-old lady with an enlarged thy-
roid gland. Note the nodular appearance. (b) Huge goiter
in a 58-year-old lady. Note the multinodular appearance.
(c) Large goiter in a 67-year-old lady. Note the multinodu-
12.2.4 Complications
ofMultinodular Goiter (MNG)
lar appearance with the largest in the left lobe. (d) Large
mulit-nodular goiter in a 64-year-old lady affecting
mainly the right lobe
most important complication, which usually
occurs in long-standing cases. The clinical criteria of malignant transformation are listed in
Neglected or untreated MNGs may present with
Table12.4.
complications, which include the following:
12.2.4.3 Compression Manifestations
12.2.4.1 Toxicity
Secondary thyrotoxicosis may develop in
10–20% of cases, usually above the age of
30years. Toxic nodular goiter is treated by surgery after patient preparation.
12.2.4.2 Malignant Transformation
The development of papillary thyroid cancer
(PTC) or follicular thyroid cancer (FTC) is the
The pressure manifestations may result from the
rapidly enlarging thyroid, retro-sternal extension,
malignancy, or hemorrhage. The sequelae will
depend on the structures compressed (or
inltrated):
– Trachea: Dyspnea results from displacement
of the trachea to one side by an enlarging unilateral goiter, compression from both sides in
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288
M. Sakr
Table 12.4
of a multinodular goiter
Glandular criteria Extra-glandular criteria
– Rapid recent growth
– Fixation of the
– Consistency
– Edges become
– Onset of pain
Clinical criteria of malignant transformation
– Compression
symptoms become
swelling—restricted
mobility with
deglutition
becomes harder
ill-dened
more evident
– Vocal cord paralysis
due to inltration of the
recurrent laryngeal
nerve (RLN)
– Horner’s syndrome due
to inltration of the
cervical sympathetic
trunk
– Cervical lymph node
(LN) enlargement
– Unequal carotid
pulsations
bilateral goiters (scabbard trachea), or tracheomalacia (softening of trachea) in longstanding cases.
– Esophagus: Dysphagia; however, this usually
results from inltration rather than compression and thus should alert the physician to the
possibility of cancer.
– Neck veins: the patient presents with mediasti-
nal syndrome and congested face.
– RLN: hoarseness of voice mostly occurs due
to malignant inltration rather than just pressure on the nerve.
12.2.4.4 Calcication
In long-standing cases, calcication may occur
either in the capsule or in the septa. Plain radiography is diagnostic. It results in a “hard” nodule
and may be mistaken clinically for malignancy.
12.2.4.5 Cyst Formation
Development of cysts/pseudocysts in MNGs
results from rupture of neighboring acini, hemorrhage, infection, or degeneration of nodules.
12.2.4.6 Hemorrhage
Bleeding may occur suddenly, precipitated by
straining, causing sudden increase in the size of
the gland, pain in the neck, and sudden compression of the trachea with impending suffocation
augmented by reex spasm of pretracheal muscles. Urgent treatment is necessary to relief com-
pression immediately by aspiration of the cyst,
division of the pretracheal fascia, incision, and
evacuation of the hematoma. Urgent thyroidectomy is performed to remove the hemorrhagic
nodule.
12.2.4.7 Infection
Multinodular goiters rarely get infected, but
infection has been reported to occur in a MNG
more commonly than in a normal gland.
12.2.5 Investigations
12.2.5.1 Laboratory Findings
The most important parameter is the basal TSH
serum level. It is normal in the euthyroid state. If
not, fT4 and fT3 should be performed. If an autoimmune process is suspected, thyroid autoantibodies should be tested such as the
anti-thyro-peroxidase (TPO) and anti-TSH
receptor antibodies. It must be noted that they
may also be positive in healthy individuals or
patients with goiter or autonomy [38].
12.2.5.2 Imaging Findings
Ultrasonography (US)
All patients scheduled for thyroid (or parathyroid) surgery should undergo a preoperative
ultrasound (US). It is the most precise tool for
evaluating the thyroid and nodule size [38]. The
normal volume of the thyroid is 7–20 mL and
nodules larger than 2 mm in diameter may be
identied [41]. Besides the size, US provides
valuable information regarding echogenicity (the
normal thyroid is iso-echogenic or slightly hyperechogenic), nodular composition as it allows differentiation between solid nodules and simple or
complex cysts, presence of calcications (micro
i.e., 1mm or less, or macro), as well as shape and
margins. Moreover, US may differentiate extrathyroidal structures from the thyroid gland and
may give information on regional lymphadenopathy [42].
Color-ow Doppler US gives further information on vascular ow and velocity. In addition,
FNAC under US guidance improves the accuracy
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12 Benign Thyroid Disease
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of palpation-guided FNAC and allows FNA cytological sample from a “suspicious” nodule.
Scintigraphy
Scintigraphy has become rare due to the progress
in US techniques. It should be performed only if
it has an impact on the therapeutic plan, for
instance in a young patient with a STN, possibly
a carcinoma, or in case of hyperthyroidism [38].
According to scintigraphy, thyroid nodules may
be “hot” in the presence of autonomously functioning thyroid tissue (rarely malignant) or “cold”
in which case the incidence of malignancy is
10–20% [43]. Cystic nodules are usually “cold.”
Radiography andTomography
Plain chest X-rays may show a substernal goiter
(Fig.12.3), and CT scan and MRI are indicated
for large tumors extending to adjacent structures
such as the mediastinum or the retro-pharyngeal
region [43].
12.2.5.3 Fine-Needle Aspiration (FNA)
For evaluation of the potential malignancy of a
nodule, US-guided FNAC may give further information. Indications are suspected malignancy
with the following ndings: young patient, previous radiation exposure of the neck, rapid growth,
cold in scintigraphy, and US ndings of
Fig. 12.3 Plain X-ray of the chest showing a mediastinal
soft tissue shadow; retro-sternal goiter (arrow)
hypo- echogenicity, loss of halo, size >1cm diameter, ill-dened margin, and the presence of
micro- calcications, in addition to hypervascularity on Doppler examination, and the presence
of enlarged cervical LNs (suspicious) [39].
12.2.5.4 Airway Assessment
Signs of signicant airway obstruction are stridor, labored breathing, intercostal retractions,
and agitation in case of RSG vena caval obstruction [44]. Indirect laryngoscopy may be helpful
and should be a routine examination [45], particularly in repeat surgery for recurrent goiter or if
there is evidence of RLN dysfunction. A chest
X-ray is evaluated for tracheal deviation and
compression [46]. Other examinations, such as
CT and MRI, are not routinely performed but may
give additional information, especially in cases
of RSG [47]. Respiratory function tests are debat-
able [48]. In patients with evidence of a compromised airway, the airway is assessed using
beroptic laryngoscopy after the application of
topical anesthesia and oxygen [44].
12.2.6 Management ofMNG
12.2.6.1 Nonoperative Treatment
Conservative treatment of MNG with L-thyroxin
(L-T4) may be effective or at least partially, in
reducing the volume of relatively small, benign,
solitary, solid thyroid nodules [49–53]. LowTSH suppression is effective in reducing nodule
volume [28]. However, some authors reported a
volume reduction without treatment, probably
due to spontaneous regression [47, 50].
Alternatively, radioactive iodine (RAI) therapy may be used in elderly patients or those with
contraindications for surgery [54]. The lifetime
risk of cancer due to RAI is negligible in patients
over 65years old.
In Graves’ disease, surgery, RAI therapy, and
treatment with anti-thyroid drugs (ATDs) are all
options, whereas autonomy is a classical indication for radiotherapy except in solitary autonomous nodules where surgery is equally effective.
Thyroid neoplasms are an indication for surgery
as are I2-induced hyperthyroidism and intractable
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M. Sakr
hyperthyroidism not responsive to conservative
management [38].
12.2.6.2 Surgical Treatment
Indications andExtent ofSurgery
Indications for surgery of the thyroid gland vary
depending on the pathology: in euthyroid MNG,
the main indications are goiter size, compression
symptoms, and suspected malignancy. Various
surgical options exist, ranging from hemithyroidectomy (lobectomy) to total thyroidectomy
(if the thyroid gland contains nodules
throughout).
Because of a reportedly high-frequency complications in some series, controversy exists
about the routine use of total thyroidectomy (TT)
for the management of “benign” MNG [55–59].
However, it is noteworthy that, when performed
by experienced hands, TT, compared with subtotal resection, does not increase morbidity in
benign pathologies [58–63]. In cases of retrosternal goiter (RSG), TT is preferred owing to the
malignant potential and in order to reduce the
recurrence rate (RR) [64]. It is important to
emphasize that proper training and surgical experience are signicantly associated with low complication rates in thyroid surgery [65, 66].
Multinodular Goiter (Benign/Thy 2)
Patients with MNG, diagnosed with FNA as
being benign (Thy 2) could either receive denitive surgery or annual monitoring with TSH levels (Table12.5).
Table 12.5 Indications of surgery and annual TSHmonitoring for patients with MNG (Thy 2)
Indications of surgery
– Compression
syndrome
– Cosmetic reasons
– Follicular or Hurthle
cell lesion (Thy 3)
– Concern about
malignancy (Thy 4)
– Persistent
troublesome toxic
nodules
Indications of annual TSH
monitoring
– The goiter is small or
modest in size
– The patient is
euthyroid with normal
TSH
– Clinically asymptomatic
without signs of
compression
– FNAC of all
suspicious nodules is
benign
Thyroid Nodules Associated withHypo-/
Hyperthyroidism
These nodules are very unlikely to be malignant.
They are more likely to be benign toxic nodule or
Hashimoto’s thyroiditis. The frequency of malignancy in cold nodules is 10–20% and only 4% in
hot nodules [67, 68]. These nodules should still
be aspirated and if conrmed to be benign (Thy
2) after two aspirates 3–6months apart, with no
other suspicious features, can be safely managed
by an endocrinologist, and referred back for reevaluation if there are any change in the
swelling.
Dominant Nodule inMNG
Patients with hyper- or hypothyroidism associated with MNG with no other suspicious features
in history and clinical examination have a low
risk of thyroid cancer [24]. When a “dominant
nodule” is noted to be growing and become suspicious, it should be aspirated and treated according to cytology results. Patients at low risk, who
are euthyroid with MNG of long duration and
slow growth, have a very low risk of thyroid cancer [24]. Patients can be observed at intermediate
or long intervals.
Thyroid Cystic Swelling
It should be clearly stated that in order to help the
pathologist in interpreting FNAC, the cyst should
be aspirated to dryness under US-guidance, and
any residual mass should be noted and subjected
to FNAC immediately as a separate specimen
[24]. For a thyroid cyst that is shown to be benign
on FNAC and does not recur at follow-up, clinical observation alone may be sufcient. A recur-
rent thyroid cyst should be re-aspirated during
follow-up and the sample sent for cytology.
Patients with high-risk factors in history and clinical examination can be considered for diagnostic
lobectomy. Some surgeons would consider diagnostic lobectomy for a cyst that has recurred for
three times or more. Surgery can also be considered at patient’s request.
Results ofSurgical Treatment ofMNG
The rate of secondary hemorrhage is approximately 1%, whereas the rate of persistent RLN
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12 Benign Thyroid Disease
291
paresis and of hypoparathyroidism has dropped
to <1% in the last 2 decades [69, 70]. Adequate
surgery is part of the prophylaxis of recurrence
[71]. In a case-control study, young age and multiple nodules at initial surgery have been identied as independent risk factors of recurrence
[57]. Despite suppressive L-T4 treatment postoperatively, 14% of patients develop recurrence
after subtotal thyroidectomy (STT) after a median
follow-up of 14.5 years [72]. Without suppression, the RR reaches up to 41% [73, 74]. Recently,
TT is being increasingly accepted and recommended for the treatment of MNG [60, 75].
Prophylaxis ofRecurrence
In addition to adequate surgery, postoperative suppression therapy with the proper dose of L-T4 is
important for preventing recurrence [71]. In I2deciency goiter with no substitution, 25% of
patients will have a recurrence. The aim should be
a TSH in the lower normal range (0.3–1mU/L), in
contrast with malignancies where the TSH should
be suppressed to <0.1mU/L.Strong TSH suppression, however, increases the risk of cardiac complications and accelerates osteoporosis [76, 77].
Treatment ofRecurrent Goiter
Surgery for recurrent goiter has a higher complication rate than in the primary setting [33, 64],
with signicantly higher temporary and permanent RLN palsy (5% and 3%, respectively) [78].
The indication is therefore restricted to suspicion
of malignancy. Preoperatively, indirect laryngoscopy for RLN function is essential. Intraoperative nerve monitoring may be helpful in
identication of the nerve [46]. If preoperative
unilateral RLN paresis is present, if possible,
only ipsilateral hemithyroidectomy should be
considered [71].
12.3 Retro-sternal Goiter (RSG)
12.3.1 Introduction
Terms such as retro-sternal, sub-sternal, intrathoracic, or mediastinal have been used to
describe a goiter that extends beyond the connes
of the neck into the thoracic cavity. However,
there is lack of consensus regarding the exact
denition of a retro-sternal goiter (RSG) [64,
79–86]. Although the great majority of RSGs are
extensions from the neck, rarely (<1%), pure
intra-thoracic goiters do occur.
Most of these goiters are slow growing and
often do not cause symptoms until the mass
reaches a critical size and causes compression
symptoms. Although the majority of these lesions
are benign in nature approximately 6–16% may
be malignant, and a few cases may exhibit thyrotoxicosis [87–90]. Usually, malignancy must be
ruled out when RSGs are discovered in asymp-
tomatic individuals. Because FNA is often difcult or inadvisable in this location, many authors
have advocated surgical removal of all RSGs even
when asymptomatic. Very rarely, a left- sided cervical goitre descends into the right side of the
chest this is called a “crossed sub-sternal goiter.”
Controversies exist regarding the incidence of
tracheomalacia in RSG, with its anesthetic and
surgical implications. Superior vena cava (SVC)
with variable incidence and signicance has been
associated with RSG. Even more importantly,
from a surgical point of view, the approach
required for an RSG is still a subject of signicant debate.
12.3.2 Denitions ofRetro-sternal
Goiter (RSG)
There are several denitions of RSG in the literature as follows:
– In 1957, Goldenburg and Lindskog [91]
dened RSG as “one reaching the level of the
fourth thoracic vertebra on chest X-ray.”
– In 1994, Singh and co-workers [85] suggested
that RSG was “when >50% of the goiter was
below the plane of the thoracic inlet”
– In 1998, Vadasz and Kotsis dened RSG as “a
thyroid gland reaching the level of the aortic
arch” [92].
– In 2006, Wu etal. [93] described three types of
RSG according to clinical features and thyroid
position; type I goiters, when the lower pole of
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292
the gland is over the arch of the aorta; type II
goiters are those below the arch of the aorta and
extending into the posterior mediastinum, while
type III are giant goiters located in the chest or
when the patient present with SVC syndrome.
– In 2007, Candela et al. [94] dened RSG as
“any goiter that descended below the plane of
the thoracic inlet or growing into the anterior
mediastinum for >2cm with the patient in the
surgical position.” This is the generally
accepted denition.
– In 2008, White and co-workers [82] dened
RSG as “any goiter, which required dissection
in the mediastinum.”
12.3.3 Incidence
The exact incidence of RSG is generally difcult
to assess, but reportedly ranges from 1.7 to 21%
of patients undergoing thyroidectomy [88–90,
92, 95], and represents up to 7% of mediastinal
tumors, ranging from 5 to 19% [80, 88]. Usually,
patients with RSG are in their fth decade of life;
however, patients as young as 15years and old as
90 years were reported [80]. The female:male
ratio is 3:1 or 4:1 [96]. Approximately, 5–40% of
patients with RSG are “asymptomatic.”
Tracheomalacia has been reported in 0–10.3% of
patients with RSG and accounts for the majority
of tracheostomies performed in 0–8.6% of these
patients [82]. The incidence of cancer in patients
with RSG is reported to be between 2.5% and
21%. A recent review of evidence-based management of RSGs concluded that the incidence of
malignant transformation is equivalent in RSGs
to those residing entirely in the neck [82].
M. Sakr
Fig. 12.4 Primary retrosternal goiter: intra-thoracic goiter originating in the chest Blood supply is derived from
intra-thoracic vessels
STA
ITA
12.3.4 Anatomical Classication
The location of RSGs is the superior mediastinum, either anteriorly [80, 97] or posteriorly [97,
98]. They are classied as either “primary”
(Fig.12.4) or “secondary” (Fig.12.5) goiters.
t.me/Dr_Mouayyad_AlbtousH
Fig. 12.5 Secondary retrosternal goiter: originating from
the left thyroid lobe. STA: superior thyroid artery; ITA:
inferior thyroid artery
12 Benign Thyroid Disease
293
12.3.4.1 Primary RSG
(Intra-thoracic—Aberrant)
Primary mediastinal or RSGs (also named aberrant) are those without any direct connection to
the cervical thyroid gland. Further denitional
criteria include (1) blood supply from a mediastinal (not cervical) source, (2) a normal or absent
cervical thyroid gland, (3) no history of prior thyroid surgery, and (4) a lack of similar pathology
in the other portions of the thyroid gland. It
accounts for <1% of all RSGs and originates
from ectopic (accessory) embryonal thyrocytes
that have descended into the chest with the arch
of the aorta [82, 99, 100].
12.3.4.2 Secondary RSG (Mediastinal
Plunging)
Secondary RSGs constitute the majority of the
cases. They are cervical goiters that have migrated
to the intra-thoracic location favored by many
factors. These include (1) the increasing weight
of the thyroid gland, (2) negative intra-thoracic
pressure, (3) respiratory movement, (4) swallowing, (5) shortness of the neck, and (6) absence of
anatomical structure that anchors the thyroid
between the lower neck and the thoracic inlet
[87]. Secondary RSGs receive their blood supply
from the superior and inferior thyroid arteries
(ITAs) [82, 100].
Approximately, 75–90% lie in the “anterior”
mediastinum, usually originating from the lower
pole of the thyroid gland and descend along the
antero-lateral aspect of the trachea and anterior to
the RLN and carotid vessels [87, 101].
Occasionally (10–15%), a goiter originating from
the postero-lateral aspect of the thyroid may
descend into the “posterior” mediastinum pushing the esophagus to the opposite side and causing
forward displacement of the trachea and tilting of
the larynx. In this case, the RLN, ITA, and carotid
vessel lie anterior to the goiter [64].
A goiter, which arises from the left lobe, may
descend to the right due to the presence of major
vessels and is termed “crossed RSG.” A goiter
that rises in the neck with deglutition and then
descends again is termed “plunging goiter.”The
main differences between the primary and secondary RSGs goiter are shown in Table12.6.
Table 12.6 Differences between primary and secondary
retros-ternal goiters (RSGs)
Differences Primary RSG Secondary RSG
Origin Ectopic
Blood supply
Connection
with cervical
thyroid gland
Cervical mass None Yes in 80–90% of
thyroid
tissue in the
chest
Intrathoracic
aorta
None Usually contiguous
Extension of cervical
thyroid into the chest
Inferior thyroid
artery
with the cervical
gland or connected
by a brous band
patients
12.3.5 Clinical Manifestations
12.3.5.1 Symptoms
Usually, patients are in their fth decade of life,
with a female to male ratio of 3–4:1.
Approximately, up to 40% of patients are asymptomatic for many years [102, 103], with incidental discovery on X-ray revealing a mediastinal
mass or tracheal deviation [84, 104].
A neck lump is present in up to 65% of
patients. Other symptoms are the result of compression of intra-thoracic structures (airway,
esophagus, blood vessels, or nerves), separately
or in combination [87, 101]. Compression of the
airway occurs in about 32–50% of patients and
may present with dyspnea, stridor, or a choking
sensation [90, 96, 105, 106] and may require
urgent intubation or a semi-urgent operation in
22% [90]. In some patients, dyspnea is experienced only when the head is turned toward one
side or by lying down at. Dysphagia is present
in about 30–40% being more common with RSGs
located in the posterior mediastinum. Hoarseness
of voice is reported in approximately 13% of
patients [64, 81, 88, 104]. A rare neurological
presentation that may occur is Horner’s syndrome (meiosis, anhiderosis, and ptosis) [107].
Unusual symptoms result from vascular compression causing downhill upper gastrointestinal
bleeding from esophageal varices, effort axillary
vein thrombosis, transient ischemic attacks
(TIA), and cerebral edema. Hyperthyroidism
may be observed in cervical or RSGs, resulting
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M. Sakr
from an autonomously functioning nodule or
may be precipitated by ingestion of iodides found
in certain expectorants or radiographic contrast
media [64, 81, 88, 104].
12.3.5.2 Physical Examination
A palpable lump in the neck, with impalpable
lower border and dull sternal percussion, may be
demonstrated in about 80–90% of patients [88].
Other signs include dilated neck and chest veins
(Fig. 12.6) and tracheal deviation. Raising the
arms or hyperextension of the neck may cause
dilatation of cervical veins and ushing of the
face or even respiratory difculty/stridor
(Pemberton’s sign). Although no specic incidence of thyrotoxicosis is reported in patients
with SSG, it is expected not to be different from
that incidence of totally cervical nodular goiter.
Common signs and symptoms of RSG are summarized in Table12.7.
12.3.6 Diagnosis
12.3.6.1 Laboratory Studies
The following blood tests can be helpful preoperatively: thyroid function tests (TSH, free
T4), calcium, albumin and parathyroid hormone (PTH). TSH and FT4 are used to assess
thyroid hormone production and the need for
preoperative treatment of hyperthyroidism or
thyroid hormone replacement in cases of hypothyroidism. Calcium, with albumin correction,
and PTH can help predict the need for calcium
(and vitamin D) replacement after
thyroidectomy.
12.3.6.2 Pulmonary Function Tests/
Flow-Volume Loops
Pulmonary function studies may indicate the
presence and level of airway obstruction and
serve as a baseline to measure improvement after
thyroidectomy (Fig.12.7) [96].
12.3.6.3 Plain Chest X-Ray (CXR)
Plain CXR is the most “cost-effective” method
for diagnosis of RSG.Findings include deviation
and/or compression of the trachea (Fig. 12.8),
soft tissue density or a mass, and occasionally
calcications (Fig.12.9).
12.3.6.4 Computed Tomography (CT)
Scan andMagnetic Resonance
Imaging (MRI)
Both, CT scan (Fig.12.10) and MRI (Fig.12.11)
can provide more precise information about the
relationship between the various intra-thoracic
organs and the goier. This information helps the
surgeon to plan for both the intubation and operation [96, 108].
Fig. 12.6 Venous congestion and dilatation of the neck
and upper chest veins due to obstruction by a large
retrosternal goiter in a 51-year-old patient
t.me/Dr_Mouayyad_AlbtousH
Table 12.7
RSG
Symptoms Signs
• Asymptomatic
• Neck lump
• Compression
– Airway: dyspnea,
– Esophageal: dysphagia
– Nerve: hoarseness of
– Vascular: SVC
SVC superior vena cava; TIA transient ischemic attack; GI
gastrointestinal
Clinical symptoms and signs of patients with
• Cervical mass
• Dilated veins of
the neck
stridor, raspy cough,
wheezing, chocking
voice, Horner’s
syndrome
syndrome, TIA,
cerebral edema, GI
bleeding
• Tracheal
deviation
• Flushing of skin
• Pemberton’s sign
• Horner’s
syndrome
5
Flow (L/s)
-4
12 Benign Thyroid Disease
4
3
2
295
1
0
-1
-2
-3
Expiration
Inspiration
Before therapy
Fig. 12.7 Flow volume loops (shown schematically) of a
patient (stippled curves) with a large RSG before (left
panel) and 12 months after (right panel) therapy. The
solid curves represent a subject with normal lung func-
Expiration
Inspiration
After therapy
tion. Tracheal compression by RSG causes upper airway
obstruction, which primarily affects the inspiratory capacity, as indicated by the arrows
Fig. 12.8 Chest X-ray showing left tracheal deviation
(arrow) by a retrosternal goiter (RSG)
Fig. 12.9 Plain X-ray showing calcication in a retrosternal goiter with right tracheal deviation
t.me/Dr_Mouayyad_AlbtousH
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