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424
Key Box 37.27
Manipal Manual of Surgery
Serum Thyroglobulin
Normal value: The normal value for thyroglobulin is 3
to 40 nanograms per milliliter.
Above 50 nanogram/ml suggests malignancy.
Above 100 nanogram/ml suggests pulmonary or
skeletal metastasis.
It is produced by follicular cells of the thyroid. Hence
elevated in well-differentiated carcinoma. Not in
medullary carcinoma thyroid.
Hence, it is a tumour marker of well-differentiated
carcinoma.
Anti-thyroglobulin antibodies (ATA-TgAb) are found in
Hashimoto’s thyroiditis and in Graves’ disease.
ANAPLASTIC CARCINOMA
Incidence: 10–12% of cases.
Fig. 37.45: A 40-year-old male with 3 cm hard, fixed nodule
with recurrent laryngeal nerve paralysis. FNAC—anaplastic
carcinoma
Clinical Features (Key Box 37.28)
Key Box 37.28
Anaplastic Carcinoma Thyroid
The most rapidly growing thyroid malignancy
Advanced age group at presentation
Advanced nature of presentation
Gross local infiltration—Berry’s sign positive
No form of treatment is successful.
Intrinsic carcinoma of larynx spreading outside and
infiltrating the skin should be considered as a differential diagnosis.
• Common in elderly women around 60–70 years of
age.
• Majority of the patients present with rapidly growing
thyroid swelling of short duration. The surface is
irregular, and consistency is hard.
• Early infiltration of the trachea results in stridor
(scabbard trachea).
• Infiltration of carotid sheath: In such cases, common
carotid artery pulsation will not be palpable. This is
described as ‘Berry sign positive’. However, superficial temporal artery pulsations will be palpable. It
means the lumen is not blocked but common carotid
artery is engulfed.
• Early fixity is characteristic. Thus, the respectability
rate is almost nil (Fig 37.45).
• Pathologically highly pleomorphic malignant cells
Section II • General Surgery
are seen (Fig. 37.46).
Fig. 34.46: Highly pleomorphic malignant cells. (Courtesy: Prof
Laxmi Rao, Head, Department of Pathology, KMC, Manipal)
Diagnosis
It is established by FNAC, other investigation being CT
scan.
Treatment
• Due to the gross local infiltration into the vital
structures in the neck, such as common carotid artery
and trachea, the respectability rate is low.
• However, very rarely, a surgeon will get an opportu-
nity to excise isthmus so as to relieve compression of
the trachea.
• Postoperative radiotherapy is given as a palliative
treatment.
• In many cases, death occurs within 6 to 8 months.
Thyroid Gland
MEDULLARY CARCINOMA OF THE THYROID (MCT)
• These tumors arise from parafollicular ‘C’ cells which
are derived from ultimobranchial bodies and not from
thyroid follicle. Parafollicular cells are pale-staining
cells found in the thyroid gland. They are always
situated within the basement membrane, which
surrounds the entire follicle.
• These tumors present in two different ways.
. Sporadic is common, seen in about 80–90% of
1
cases.
2. Familial variety presents as a part of multiple
endocrine neoplasia (MEN).
MEN Type I
• Pituitary adenoma
• Parathyroid adenoma
• Pancreatic adenoma
MEN Type IIa
• Parathyroid adenoma
• Phaeochromocytoma
• Medullary carcinoma of thyroid
• When it is associated with mucocutaneous neuromas
involving lips, tongue, eyelids, it is called Sipple
syndrome, with an occasional marfanoid habitus
(MEN type IIb) (Fig. 37.47).
425
Fig. 37.47: FNAC proved medullary carcinoma with muco-
cutaneous neuroma—MEN type IIb
Fig. 37.48: Medullary carcinoma thyroid—characteristic
amyloid stroma
Pathology: It has got a characteristic amyloid stroma
(Fig. 37.48).
• These tumours are not TSH-dependent and do not
take up radioactive iodine.
Hormones Produced by MCT
• Calcitonin (Key Box 37.29)
• Prostaglandins
• Serotonin (5-HT), ACTH
Spread
• Both by lymphatics and blood, thus worsening the
prognosis.
Key Box 37.29
Calcitonin and Medullary Carcinoma Thyroid
Not measurable in normal persons
MCT produces very high levels
It is the tumour marker of MCT
Level decreases after thyroidectomy
Level increases in case of recurrence
Prophylactic thyroidectomy in relatives, if calcitonin
levels are high
Treatment
1. Total thyroidectomy with modified radical dissection
• Before proceeding with surgery, look for an
associated phaeochromocytoma.
. The lymph nodes are treated by radical block
2
dissection because they are fast-growing, when
compared to papillary carcinoma.
If there are multiple secondaries in the bone, oral 131I has no
role because this tumour does not arise from thyroid cells.
Only palliative radiotherapy can be given.
Clinical Criteria for the Diagnosis of Carcinoma
of Thyroid: Summary
1. A thyroid swelling which is rapidly growing.
. Thyroid swelling with lower deep cervical lymph
2
nodes and lymph nodes in the posterior triangle
(papillary carcinoma thyroid) involved.
3. Hard gland, fixed to the trachea—anaplastic
carcinoma of the thyroid.
4. Thyroid swelling with a rapidly growing, vascular,
pulsatile swelling, commonly in the skull (follicular
carcinoma).
Section II • General Surgery
426
Table 37.7 Summary of the malignant tumours of thyroid gland
Papillary Follicular Anaplastic Medullary
1. Aetiology Irradiation Endemic goitre Unknown Sporadic or familial
2. Incidence 60% 17% 13% 6%
3. Age (years) 20–40 30–50 50 and above Middle age
4. Diagnosis Thyroid swelling with Thyroid swelling with Thyroid swelling, Difficult to diagnose
lymph node metastasis bony metastasis local fixity, stridor clinically
5. Microscopy Orphan Annie-eye nuclei, Angioinvasion, Poorly differentiated Amyloid stroma-like
psammoma bodies capsular invasion cells carcinoid
6. Spread Lymphatic Blood Local infiltration Lymphatic, blood
7. Investigation FNAC Frozen section FNAC, incision biopsy FNAC, calcitonin
8. Treatment of the Near total/total Near total/total Isthmusectomy, Total thyroidectomy
primary thyroidectomy thyroidectomy external RT
9. Treatment of Functional neck Radioiodine
metastasis dissection or external RT radiotherapy
10. TSH dependence Yes Yes No No
11. Hormone production Very rare Very rare No Calcitonin, 5-HT, ACTH
12. Prognosis Excellent Good Worst Bad
Manipal Manual of Surgery
131
I Palliative external Radical block dissection
5. Thyroid swelling with hoarseness of the voice
indicating infiltration of recurrent laryngeal nerve is
a feature of malignancy.
6. Thyroid swelling with Berry sign positive (anaplastic
carcinoma of the thyroid).
7. Kocher’s test positive may be an indication of infiltration into trachea. Summary of the malignant tumours
of the thyroid gland is shown in Table 37.7.
LYMPHOMA
• It is rare. Hashimoto’s thyroiditis can predispose to
lymphoma.
• Older patients are commonly affected.
• The tumour can present as rapidly-growing, large
thyroid swelling (primary lymphoma).
• Sometimes, it can appear as a part of generalized
lymphoma (non-Hodgkin’s variety).
• FNAC may give the diagnosis—Tru-cut biopsy is
ideal.
• It is interesting to note that lymphomas of the thyroid
respond very well to chemotherapy and radiotherapy
(Fig. 37.49A and B).
SOLITARY NODULE OF THE THYROID GLAND
Definition: Solitary nodule (SN) is a clinical term
denoting presence of a single palpable nodule in the
thyroid gland (no other part of thyroid gland is
palpable) (Fig. 37.50A).
• Almost all the thyroid swellings initially can present
Section II • General Surgery
as a solitary nodule. However, puberty goitres,
Fig. 37.49A and B: Lymphoma of the thyroid gland with
mediastinal lymph nodes and superior vena caval obstruction
Watch dilated veins and also three cutaneous nodules
colloid goitres, diffuse toxic goitres produce uniform
enlargement of the thyroid gland. Multinodular
goitre (MNG) presents as multiple nodules. However,
very often a solitary nodule on clinical examination,
may turn out to be a multinodular goitre at exploration. The solitary nodule has a higher incidence of
malignancy when compared to MNG.
• It is a common surgical problem encountered by
general surgeons. By definition, one can call it a
solitary nodule when only the nodule is clinically
palpable but rest of the gland is not palpable.
• However, when a nodule is palpable and the opposite
lobe or any other part of the thyroid is palpable, it is
a ‘dominant’ nodule. It may probably be a case of
multinodular goitre (Fig. 37.50B).
.
Thyroid Gland
Figs 37.50A and B: (A) Solitary nodule. Rest of the gland is normal;
(B) Solitary nodule. Rest of the gland is enlarged—mostly it is MNG
Introduction
• It is the most common surgical disease of the thyroid
gland. Incidence is about 4%. It is 4 times more
common in women than men. About 20 to 30% of
patients may have nodules on the other side when
detected by ultrasound, thus the diagnosis changes
to multinodular goitre. Risk of malignancy is more in
a solid nodule and in men. It is about 48%. However,
in females it is about 12%. In general, incidence of
malignancy is 8–10%. Ultrasonography followed by
FNAC is the first line of investigations. Aim is to
identify a solitary nodule which has high risk, e.g.
male, solid, solitary nodule is a nodule which has
features suggestive of malignancy (Key Box 37.30).
Key Box 37.30
High Risk Solitary Nodule
Male patients with ‘solid’ nodule
Rapid growing nodule of short duration
Nodule which has restricted mobility
Nodule with jugular lymphadenopathy on ultrasound
Nodule which is hard in consistency
Nodule with hoarseness of voice
Causes of Solitary Nodule of the Thyroid Gland
(Figs 37.51 and 37.52)
Fig. 37.51: A 45-year-old
female with solitary nodule.
FNAC revealed thyroid cyst
Fig. 37.52: A 45-year-old male
presented with solitary nodule.
Hormone levels were elevated.
He underwent hemithyroidectomy—solitary toxic nodule
427
1. In about 30 to 40% of the cases, a clinically palpable
solitary nodule is a part of multinodular goitre
2. Toxic autonomous nodule
3. Adenoma
4. Carcinoma
5. Cysts
About 2 to 3% of solitary nodules are associated with hyperthyroidism. Chances of malignancy in a hyperthyroid nodule
is very low.
Indications for Surgery
• Malignant cytology: Refer to Bathesda Criteria for
FNAC thyroid
• Suspicious cytology
• Large size
• Pressure effect, substernal extension
• Clinical suspicion of malignancy
• Cosmesis
• Male sex
• Cyst—recurs after aspiration and bloodstained
fluid
Investigations
. Blood investigations
1
• T3, T4 and TSH: Free thyroxine—better indicator
of thyroid status than total T
. T3 is useful when T
4
level is borderline (T3 toxicosis). TSH is needed
when there is no clinical manifestation of hyper(or) hypothyroidism.
• Thyroid autoantibodies—when Hashimoto’s
thyroiditis is suspected.
• Serum thyroglobulin (STG)—tumour marker
. Normal value is <1–35 nanog/L
a
b. STG level above 50 nanog/L—suggests residual
(or) recurrent tumour
c. STG level goes above 100 nanog/L suggests
pulmonary (or skeletal metastasis)
d. Increased in hyperthyroidism, thyroiditis and
tumour
e. Serum calcitonin—useful for screening medullary
carcinoma when a patient has history of thyroid
cancer and presents with a solitary nodule.
2. 24 hours collection of urine for catecholamine to exclude
phaeochromocytoma (MEN II syndrome) because of
association with medullary carcinoma (Rare).
3. Ultrasonography (USG): It is noninvasive, cheap and
it has become the investigation of choice in solitary
nodule. Totally sonolucent unilocular lesions, sonolucent cyst with internal echoes, septae, nodule with
4
Section II • General Surgery
428
Manipal Manual of Surgery
homogeneous echogenicity (hyper or hypo), mixed
echogenicity and microcalcification enlargement
of jugular lymphadenopathy are a few features
suggestive of malignancy. With increasing use of high
frequency ultrasound probe, radionuclide scan is
rarely used or almost not used in the evaluation of
solitary nodule thyroid gland.
4. Ultrasound guided fine needle aspiration cytology
(FNAC): Using a 22 or 23 gauze needle attached to a
10 ml syringe, under ultrasound guidance, needle is
introduced within the gland while maintaining
negative pressure and about 4 to 6 passes are done
within the gland and syringe and needle are
withdrawn. Contents are pushed into slides and
about 6 slides are prepared and are air dried. Most
popular criteria used for FNAC thyroid is Bathesda
criteria (Table 37.8). (Bathesda is name of the pool in
Jerusalem and it is a City in central Maryland).
5. CT scan: Specific indications are: Doubt about the
origin of the swelling, large lesion with local
infiltration into vascular structures and intrathoracic
extension.
6. Isotope scan (not routinely done nowdays): Most
commonly used isotope—
99m
used for evaluation of nodule.
131
Tc.
I should not be
123
T will not detect
nodules of 1 cm size. However, it is indicated in a
‘toxic nodule’ which is ‘hot’. Rest of the gland is
suppressed, so that such patient can be managed
easily by radioiodine. It can demonstrate three
different patterns as follows Fig. 37.53).
Fig. 37.53: Radioisotope scan findings
• Hot nodule: The gland does not take up isotope but
the nodule takes it up, which is a feature of auto-
nomous solitary toxic nodule. Here, the normal
thyroid tissue is suppressed. Localisation of over
activity in a nodule with suppression of remainder
of the gland is
characteristic of solitary toxic nodule.
In toxic MNG, multiple areas show overactivity.
• Warm nodule: The entire gland takes up isotope. This
is typical of Graves’ disease (primary thyrotoxicosis)
wherein each cell is active and equally stimulated.
• Cold nodule is a nodule which does not take up
isotope. It should be remembered that only 10% of
the cold nodules are malignant. Keeping this in
mind, surgeons do not investigate MNG with
isotope scan. The assessment of malignancy is done
clinically (Key Box 37.31).
Key Box 37.31
Cold Nodule—Differential Diagnosis
1. Haemorrhage
2. Carcinoma
3. Thyroiditis
4. Thyroid cyst
Table 37.8 Bathesda criteria for FNAC thyroid
Bathesda Implied Usual
category malignancy management
rate
1. Non-diagnostic 1–4% Repeat FNAC
or unsatisfactory with image guidance
2. Benign 0–3% Clinical follow-up
3. Atypia of 5–15% Repeat FNAC or
Undetermined lobectomy
Significance/
Follicular lesion
Of undetermined
Significance
(AUS/FLUS)
4. Follicular neoplasm 15–30%
or suspicious of
follicular neoplasm
5. Suspicious of 60–75% Lobectomy or total
malignancy thyroidectomy
6. Malignant 97–99% Total
Section II • General Surgery
(specific type) thyroidectomy
Lobectomy
Please read the clinical notes of a case of thyroid swelling
Case of Thyroid Swelling
A 31-year-old female with solitary nodule (2 cm)
underwent FNAC—reported as adenoma. She underwent
hemithyroidectomy in a peripheral hospital which was
reported as papillary carcinoma thyroid (PCT). It was a
histological surprise. How to proceed now?
At our hospital, ultrasound neck was done again which
could not reveal any abnormality. She underwent
completion thyroidectomy (of the opposite lobe) after
4 weeks (re-exploration is done within 7 days or after
4 weeks once tissue oedema subsides completely).
Thus, the patient underwent total thyroidectomy. HPR
of opposite lobe did not show papillary carcinoma. No
lymph node dissection was done. The patient was not
given T4 for 4 weeks.
After 6 weeks,
131
I scan was done giving 1 mCi,
residual thyroid tissue was found in neck. It was
ablated with 100 mCi of
131
I.
Thyroid Gland
429
Even though the aim of surgery is to remove the entire
thyroid gland (total thyroidectomy), some parts of
gland might have been left behind by the surgeon,
specially in the region of ligament of Berry. Hence, a
routine postoperative radionuclide scan is advisable.
After ablation, she was put on T4 0.3 mg/day to be
taken in the morning on an empty stomach.
She came after 6 months with pain in the neck for
which ultrasound was done. It revealed suspicious
residual thyroid tissue.
What to do now?
Serum thyroglobulin was estimated. It was <0.2
(almost undetectable limits; Normal 0.2–55). So, the
suspicious lesion could have been some fibrous tissue
due to surgery. As thyroglobulin was normal, we did
not investigate her further.
Now it is 3 years since completion of thyroidectomy
and the patient has no disease but is on T4 0.3 mg/day.
What are the annual tests to be done?
Serum TSH, calcium, thyroglobulin, ultrasound, thyro-
globulin antibody and, if necessary, nuclear scan of neck.
COMMENTS
I have heard in a few surgical meetings, the following
statement made by a surgeon, ‘I have done total thyroidectomy, how can residual thyroid tissue be present in the
neck?’ Remember, it is always possible that some thyroid
tissue is left behind especially in the region of ligament of
Berry, tracheoesophageal groove and posteromedially.
Treatment
The final decision about treatment of solitary nodule
depends upon the clinical findings, sonography findings
and FNA cytology results. Depends upon Bathesda
criteria, decision is taken. A few examples of treatment
when diagnosis is established are given below:
• Papillary carcinoma: Total thyroidectomy
• Follicular neoplasm: Bethesda 3 or 4 : Lobectomy 5
or 6 : total thyroidectomy
• Medullary carcinoma: Total thyroidectomy with the
modified radical neck dissection
• Adenoma: Lobectomy (hemithyroidectomy)
• Toxic nodule in young: Lobectomy
131
• Toxic nodule in elderly: Lobectomy or
I ablation
• Simple cyst: If it resolves after aspiration, wait and
watch. If it recurs, do a lobectomy
• Refer to Key Box 37.32, 37.33 and Fig. 37.54.
Key Box 37.32
‘Most Common’ for Solitary Nodule Thyroid
Most common surgical disease of thyroid gland is
solitary nodule.
Most of the thyroid diseases begin as solitary nodule.
Most common investigation of choice for solitary
nodule is ultrasonography.
Most common cause of a solitary nodule is multi-
nodular goitre.
Most common cause for solid solitary nodule in a male
is malignancy.
Most commonly used investigation of choice for tissue
diagnosis is FNAC.
Key Box 37.33
What should not be Done in a Nodule
Nodule should never be enucleated.
Male solitary solid nodule should never be left alone
for observation.
Suppression therapy should never be attempted for a
solitary nodule without a definitive diagnosis.
Radioablation/suppression therapy should never be
given to a nodule causing compression on the trachea.
FNAC should not generally be done to a nodule, if it is a
post-irradiated gland or there is familial thyroid cancer.
Fig. 37.54: Algorithm of treatment plan in solitary thyroid nodule
Section II • General Surgery
430
Manipal Manual of Surgery
THYROID INCIDENTALOMA
• As the name suggests, these are incidentally detected
during head and neck ultrasonography done for some
other problems. In western countries with increasing
obesity, and short neck, it is not surprising to see
many such cases of incidentaloma detected by ultrasound.
• In such situations, the management is similar to that
of a solitary nodule.
• Any lesion more than 1 cm and lesion which is
solid should be subjected to sonography-guided
FNA.
• Depending on the results of the FNA, treatment is
recommended.
• If it is <1 cm, just follow-up with annual sonogram.
THYROIDITIS
• Viral and autoimmune thyroiditis are more common
in the thyroid gland infection of thyroid is very rare
because of its rich blood supply.
• Thyroiditis is broadly classified into granulomatous,
autoimmune and Riedel’s thyroiditis (Table 37.9).
hyperthyroidism (Hashitoxicosis) may be present.
Later, extensive intrathyroidal fibrosis results in
permanent hypothyroidism. Transient hyperthyroidism is due to destruction of cells resulting in
thyrotoxicosis.
• The thyroid follicles are destroyed by significant
fibrosis. The deep eosinophilic-staining thyroid
follicular cell, Askanazy cell, is characteristic of
Hashimoto’s thyroiditis.
• The gland can be firm to hard and sometimes rubbery
in consistency, smooth or irregular and can involve
a lobe or the entire gland.
• In many cases, thyroid antibodies are raised,
suggesting an autoimmune disorder.
Treatment
• Thyroxine 0.2 mg/day is given as a supplementary
dose.
• If there is compression on the trachea, isthmusectomy
is done to relieve compression.
• If the goitre is big and causing discomfort, subtotal
thyroidectomy can also be done.
GRANULOMATOUS THYROIDITIS
• It is also called subacute thyroiditis or de Quervain’s
disease.
• This occurs due to viral infection. It usually follows
sore throat (mumps virus has been incriminated in a
few cases).
• Patients present with fever, body ache and painful
enlargement of thyroid gland. The gland is enlarged,
tender to touch, soft to firm and a few symptoms of
hyperthyroidism occur initially.
• ESR is increased.
Treatment
Majority of the patients respond to conservative treatment in the form of analgesics and a short course of
prednisolone. There are no permanent sequelae of this
condition.
AUTOIMMUNE THYROIDITIS
• Hashimoto’s thyroiditis is the main component of
thyroiditis.
• Autoimmune aetiology is characterised by extensive
lymphocytic infiltration resulting in destruction of
thyroid follicles with variable degree of fibrosis.
• Females in perimenopausal group (40–50 years) are
Section II • General Surgery
commonly affected. Initially, symptoms of mild
COMPLICATIONS OF HASHIMOTO’S THYROIDITIS
• Permanent hypothyroidism
• Papillary carcinoma of the thyroid
• Lymphoma
RIEDEL’S THYROIDITIS
• This is a very very rare cause of a goitre which is
supposed to be a collagen disorder.
• It can be associated with mediastinal fibrosis, retro-
peritoneal fibrosis and sclerosing cholangitis.
• In this condition, there is intrathyroidal fibrosis but
extrathyroidal fibrosis is more.
• Involvement of trachea, oesophagus, internal jugular
vein, carotid artery, etc. results in dysphagia and
dyspnoea.
• As a result of fibrosis, all the thyroid follicles are
replaced by fibrous tissue.
• By the time patients present to the hospital, it is an
advanced stage and excision is very difficult.
Treatment
• Treatment with thyroxine may be necessary to treat
hypothyroidism.
• In selected difficult cases, isthmusectomy can be tried
to relieve compression on the trachea. Three types of
thyroiditis are compared in Table 37.9.
Thyroid Gland
Table 37.9 Comparison of three forms of thyroiditis
Granulomatous Hashimoto’s Riedel’s
1. Aetiology Virus Autoimmune Collagen disorder
2. Age group Young Woman at menopause Old age
3. Pathology Inflammatory cells Lymphocytes, fibrosis Extensive fibrous tissue
4. Clinical Painful, tender, smooth, sudden goitre Irregular or nodular, firm nontender Hard, irregular, fixed, nontender
5. Toxicity Initial toxicity, later normal Initial toxicity, later hypothyroidism Hypothyroidism
6. Laboratory tests ESR is increased Antithyroid antibodies No biochemical test
7. Treatment Symptomatic Thyroxine, surgery Thyroxine, surgery
8. Differential Acute bacterial thyroiditis Multinodular goitre Anaplastic carcinoma
diagnosis
431
COMPLICATIONS OF THYROIDECTOMY
1. Haemorrhage can be a primary haemorrhage which
occurs during surgery.
• Reactionary haemorrhage is more dangerous and
occurs within 6–8 hours after surgery. This is due
to slipping of ligature because of straining,
coughing, hypertension, etc.
• It is a tension haematoma which develops deep to
deep fascia, compressing the larynx. Reexploration
of neck under GA, control of bleeding points and
evacuation of haematoma should be done immediately.
• Without evacuating haematoma, an attempt to
intubate the patient may result in cardiac arrest
(as such patient will be struggling).
2. Respiratory obstruction can be due to tension haema-
toma resulting in compression of the larynx, collapse,
tracheal cartilage softening (tracheomalacia).
• Endotracheal intubation and a short course of
steroid therapy is necessary.
3. Laryngeal nerve paralysis (Tables 37.10 and 37.11).
A. Unilateral recurrent laryngeal nerve (RLN) palsy
produces a whispering voice. The opposite vocal
cord compensates. There will not be problems of
aspiration or airway obstruction (Fig. 37.55A).
B. Bilateral recurrent laryngeal nerve palsy: It is also
known as bilateral abductor paralysis. Both the vocal
cords come to be in median or paramedian position
(Table 37.10), the airway is inadequate causing dyspnoea and stridor but the voice is good (Fig. 37.55
Figs 37.55A and B: Vocal cord position in unilateral and bilateral
recurrent laryngeal nerve paralysis
B).
Table 37.10 Various positions of vocal cord in laryngeal nerve paralysis (Fig. 37.56)
Position Inference Distance from the midline
1. Median Seen in phonation Nil
2. Paramedian Bilateral Distance: 1–2 mm
RLN palsy
3. Intermediate Bilateral, combined paralysis of RLN Distance: 3–4 mm
(cadaveric) and superior laryngeal nerve
4. Full abduction Forceful inspiration Distance: 8–9 mm
Fig. 37.56
Section II • General Surgery
432
Manipal Manual of Surgery
Table 37.11 Causes of recurrent laryngeal nerve paralysis
Left RLN lesions Right RLN lesions
• Ca bronchus • Ca apex of the lung
• Ca oesophagus • Ca oesophagus
• Ca thyroid • Ca thyroid
• Operative injury • Operative injury
• Peripheral neuritis • Peripheral neuritis
• Aortic aneurysm • Subclavian aneurysm
• Mediastinal mass
• Left atrial enlargement
Treatment: Tracheostomy is required as an emer-
gency procedure. Following tracheostomy, the
patient is followed up on an outpatient basis for a
period of 8–9 months. This period is required for any
spontaneous recovery. If no recovery occurs after this
period, it requires a permanent solution. The choice
is between a permanent tracheostomy with a
speaking valve or a surgical procedure to lateralise
the cord which can be done by endoscopic method.
The former relieves stridor and preserves good voice
but has the disadvantage of a tracheostomy hole in
the neck. The latter relieves airway obstruction but
at the expense of good voice. However, there is no
tracheostomy hole in the neck.
Lateralisation of the cord
• It means to move and fix the arytenoid, vocal
process and vocal cord into an abducted position.
• Endoscopic lateralisation can be done by laser
cordotomy.
• KTP-532 nm laser is used.
• It is minimally invasive, single procedure, quick
recovery.
C. Superior laryngeal nerve (SLN): It is a branch of
vagus, gives a ‘motor’ branch—external laryngeal
nerve. Dissection and retraction of the upper pole
of the right thyroid lobe to reveal the external
branch of the superior laryngeal nerve in the
cricothyroid space of Reeves. This nerve
cricothyroid which is adductor of the cord.
Paralysis causes weak and husky voice and
inability to raise the pitch of voice. This is of
particular importance in singers. Amelita Galli
Curci, an Italian opera singer lost her voice
following thyroidectomy due to damage to
SLN.
• Large internal laryngeal nerve supplies whole
supraglottic larynx—sensory innervation to the
epiglottis, pyriform sinus and larynx as far down
Section II • General Surgery
as vocal folds.
supplies
D. Combined (complete paralysis):
• Unilateral: This results in paralysis of all muscles
of larynx on one side. Vocal cord will be in
cadaveric position. The healthy cord is unable
to approximate the paralysed cord, thus causing
glottic incompetence. This results in hoarseness
of voice and aspiration of liquids through glottis.
Cough is ineffective due to air wastage.
Treatment includes procedures to medialise the
cord and speech therapy.
• Bilateral: This is an uncommon condition. This
results in paralysis of all the intrinsic muscles of
the larynx. Both vocal cords assume cadaveric
position. There is also a total anaesthesia of
larynx.
It is better to identify RLN in all cases of thyroidectomy—
specially total thyroidectomy and lobectomy.
4. Permanent hypothyroidism can develop slowly after
thyroid surgery especially after subtotal thyroidectomy for Graves’ disease. It takes 2–3 years for manifestation of hypothyroidism to become apparent.
5. Permanent hypoparathyroidism is managed with
calcium tablets or with 1, 25-dihydroxy cholecalciferol.
6. Thyrotoxic crisis (storm)
• Thyrotoxic storm occurs in patients with primary
thyrotoxicosis who are improperly treated or
prepared for surgery. At surgery, due to handling
of the gland, sudden release of thyroxine into the
systemic circulation results in thyrotoxic crisis
(Key Box 37.34).
• Hyperpyrexia—above 105°F, severe sweating,
gross dehydration, hypovolaemic shock and tachycardia are the diagnostic features.
• It is treated by following measures:
ICU admission and resuscitation: O
–
, correction
2
of dehydration by rapid IV fluids.
– Cold tepid sponging, to control the temperature.
– IV and oral propranolol 2–4 mg and as necessary.
Key Box 37.34
Thyrotoxic Storm Prevention
Euthyroid before surgery
β-blockers, carbimazole
Lugol’s iodine
Good anaesthesia
Perfect haemostasis
Gentle manipulation
Thyroid Gland
– Hydrocortisone 100 mg, thrice daily.
– Carbimazole or propyl thiouracil
– In spite of the above treatment, mortality is high.
What is Wolff-Chaikoff effect?
• On ingestion of a large amount of iodine, there will
be reduction of thyroid hormones.
• It is an autoregulatory mechanism which inhibits
organification in the thyroid gland.
• This principle is used to treat hyperthyroidism
(especially thyroid storm by infusion of iodine—large
quantities).
Prevention is better than ‘cure’. With adequate preparation,
thyrotoxic storm can be prevented.
7. Wound infection: It is not common to get wound
infection after thyroid surgery. However, antibiotics
are started, if there is evidence of local erythema,
tenderness and if the patient has fever.
8. Scar hypertrophy and keloid.
. Stitch granuloma: May occur with/without sinus
9
formation and is seen after the use of nonabsorbable
suture material. Absorbable ligatures and sutures
(vicryl) can be used throughout thyroid surgery
except for skin closure where silk is still appropriate.
MISCELLANEOUS
LINGUAL THYROID
• Occasionally, a patient presents with a small swelling
in the middle of the tongue at the junction of anterior
2/3rd and posterior 1/3rd of the tongue.
• It could be lingual thyroid—an aberrant thyroid
tissue found in the region of foramen caecum on the
tongue.
• Foramen caecum represents the junction of epithelial
floor of the mouth with proximal portion of thyroglossal duct.
• Even though lingual thyroid is rare, it can give rise
to significant complications (Fig. 37.57).
433
Fig. 37.57: Four centimetre lingual thyroid in the classical
location causing dysphagia—successfully removed with LASER
Diagnosis
• Usually made on clinical grounds.
• Thyroid scan—ultrasound of neck is done to find out
whether thyroid tissue is present or not (often it is
absent).
99m
Tc (technetium) scan will detect ectopic thyroid
•
tissue (Fig. 37.58).
Differential Diagnosis
1. Ectopic salivary gland tumour: Tongue is the
commonest site. To begin with, mucosa is normal,
starts as a submucosal swelling.
2. Gumma: Rare nowadays. It is a midline, indurated,
firm, smooth swelling, painless.
3. Lymphangioma and haemangioma: These are
present since birth, more diffuse, fluctuant cystic
swellings. Haemangioma is compressible and lymphangioma is transilluminant.
Treatment
• Small dose of thyroxine may decrease the size of the
swelling (similar to a puberty goitre) as a treatment
of hypothyroidism or to suppress TSH
• Large swelling with significant symptoms needs to
be excised. Laser excision is better.
• Radioactive iodine to suppress/destroy can be given.
Clinical Features
• Common in females (3:1)
• Swelling in the tongue in the classical location, firm
in consistency, can be irregular. Impairment of
speech, haemorrhage, dysphagia, airway obstruction
may be the presenting features.
• Majority of patients have hypothyroidism (70%) and
10% are cretins.
Fig. 37.58:
Lingual thyroid may be the only thyroid tissue present in a
patient. Hence, a thyroid scan is done to confirm the presence
of normal thyroid tissue.
99mTc
(Technetium) scan showing lingual thyroid
Section II • General Surgery