sample chapter clinical manual of surgery 1e by s devaji rao to order call sms at 91 8527622422

349

24.1. Development of thyroid 34924.2. Surgical anatomy of thyroid 34924.3. Physiology 35024.4. Diseases of thyroid 350

• Thyroglossal cyst / sinus / fi stula 350 • Lingual thyroid 351 • Retrosternal ectopic / accessory thyroid 352 • Suppurative thyroiditis 353 • De Quervain’s thyroiditis 354 • Subacute lymphocytic thyroiditis and postpartum

thyroiditis 354 • Hashimoto thyroiditis 354 • Riedel’s thyroiditis 355 • Neoplasms 355 • Adenoma 355 • Follicular carcinoma 355

• Papillary carcinoma 356 • Anaplastic carcinoma 357 • Medullary carcinoma 357 • Lymphoma 357 • Nontoxic goitre 358 • Thyrotoxicosis 359

24.5. Symptoms of thyroid diseases 360 • Analysis of symptoms 360

24.6. Clinical evaluation 363 • Eliciting history 363 • Physical examination 364

• Thyroid 364 • Relevant areas 370 • Lymphatic system 373 • General 373

Chapter Outline

Chapter 24

ThyroidP. S. Venkatesh Rao

is attached to the larynx, which makes the gland rise on swallowing.● Isthmus is the thyroid tissue which connects the two

lobes of thyroid● Pyramidal lobe is a vertical tongue of the thyroid and

extends from the isthmus towards the hyoid bone. It is a remnant of the embryological descent of the gland

● Aberrant (ectopic) thyroid tissue may be found any-where in the path of descent, near the midline:● If undescended, at the back of the tongue ( lingual

thyroid )● If excess descent in the anterior mediastinum

( retrosternal e ctopic thy roid )● Rarely elsewhere in the neck, chest or abdomen Accessory thyroid tissue, in addition to normal thyroid

can also occur in any of these locations.

Relations ● Parathyroid glands, a pair on each side, are situated

posterior to the lobes of the thyroid and receive branches from the inferior thyroid artery

● External branch of superior laryngeal nerve is closely related to the superior pole and its damage may lead to interference in high notes in speech and singing

24.1 DEVELOPMENT O F THYROID The thyroid gland is derived from the epithelial proliferation called medial anlage in the floor of the pharynx, as an off-shoot of the primitive alimentary tract, from a point called foramen caecum, at the junction of anterior two-thirds and posterior one-third of the tongue in the midline. The median anlage as a tubular structure descends from the floor of pharynx down into the neck, where it is joined by a pair of lateral components developing from the ultimobranchial bodies, which arise as a diverticulum of the fourth pharyn-geal pouch. These provide the neuroendocrine C cells.

The gland descends into the neck in front of the foregut, and lies anterior to the trachea, and during this migration it is attached to its point of origin by a narrow tube called thyroglossal duct . The thyroglossal duct disappears around 6 weeks of age. Any part of this duct may persist to form a ‘thyroglossal cyst’ .

24.2 SURGICAL A NATOMY OF THYROIDThyroid is a butterfly-shaped gland with two lobes, one on either side of the trachea, invested by pretracheal fas-cia, which sends septa into the substance of the gland. It

PART | III System and Region Based Diseases350

● Recurrent laryngeal nerve lies in the tracheoesophageal groove, and passes between the branches of inferior thy-roid artery, damage of which results in hoarseness (uni-lateral damage) and stridor (bilateral damage) Blood supply is very rich to the thyroid gland, derived

from superior and inferior thyroid arteries, which are branches of the external carotid artery and thyrocervical trunk, respectively.

Venous drainage is through the superior, middle and inferior thyroid veins draining into the facial, internal jugu-lar and brachiocephalic veins, respectively.

Lymphatic drainage of the thyroid occurs through mid-dle and lower deep cervical (Levels 3 and 4), pretracheal, prelaryngeal (Delphic nodes), paratracheal (Level 6) and mediastinal nodes.

Histology

The thyroid is composed of acini (follicles), which are spherical, and lined with the epithelial cells. These cells secrete thyroid hormones, which are stored in the colloid of the follicle. C cells, also called parafollicular cells, are found between the follicles and they secrete calcitonin.

24.3 PHYSIOLOGY Two hormones are secreted by the thyroid gland. They are: ● Thyroxin and its analogues ● Calcitonin

Thyroxin and its Analogues

Follicular cells first synthesize a unique dimorphic glycopro-tein, thyroglobulin (colloid) that remains confined to the thy-roid follicle except in certain thyroid cancers (and hence may be used as a tumour marker) and in some cases of Graves’ disease. Antibodies against thyroglobulin are found in Hashimoto's thy-roiditis and Graves’ disease, and are of diagnostic significance.

Iodine trapped by follicular cells is bound to tyrosine on the thyroglobulin by the enzyme peroxidase, forming monoiodotyrosine (MIT) and diiodotyrosine (DIT). They are coupled to yield tri-iodotyrosine (T 3 � MIT � DIT) and thyroxin (T 4 � DIT � DIT). T 4 is converted into T 3 both inside the thyroid and in the periphery by 5-deiodinase. Lysosomal proteases release T 3 and T 4 from the colloid. The thyroid hormones are regulated by hypothalamic-thyroid axis through thyrotropin-releasing hormone (TRH) from the hypothalamus, which promotes the release of thyroid stimulating hormone (TSH) from the pituitary. T 3 and T 4 in turn regulate the secretion of TRH and TSH ( Fig. 24.1 ). Thyroid hormones cause a variety of metabolic and physi-ologic effects, leading to symptoms observed during excess release (thyrotoxicosis) and deficiency (myxoedema).

There are three groups of actions of thyroxin: 1. Increased metabolic activity in all cells 2. Increased beta-adrenergic receptor sensitivity 3. Stimulation of growth during the growth period

Calcitonin

It acts to reduce the concentration of calcium, by inhibiting osteoclast-directed bone absorption and by increased renal excretion of calcium.

Physiological demands of the thyroid are more during growth, pregnancy and following trauma.

24.4 DISEASES O F THYROID The diseases of the thyroid gland can be classified based on their aetiology Table 24.1 .

Thyroglossal Cyst / Sinus / Fistula

Incidence and Aetiology ● Persistence of part of the thyroglossal duct leads to for-

mation of a thyroglossal cyst ● It can lie anywhere along the course of the thyroglos-

sal tract, which extends from the foramen caecum in the posterior tongue down through the neck along the anterior midline lying close to the hyoid bone up to the suprasternal notch ( Fig. 24.2 )

● The entire duct can persist as a sinus (or fistula if it opens inferiorly)

● It occurs in early childhood or adulthood Complications: Infection of cyst, thyroglossal fistula

(See Ch. 11 )

FIGURE 24.1 Thyroid ph ysiology.

351Thyroid Chapter | 24

● When infected, skin over the cyst is hyperaemic ( Fig. 24.3 B) and tender to palpation

● When the infected cyst bursts spontaneously or is incised surgically, it results in a sinus or a fistula if there is an open communication at foramen caecum called thyro-glossal fistula, discharging purulent fluid (Ref Fig. 11.12 )

● The specific diagnostic test is the pulling up of the cyst or fistula on protrusion of the tongue, rarely when the tongue is pulled with traction ( Fig. 24.3 C)

Relevant I nvestigations ● Sinogram or fistulogram may be useful ● Isotope s can ( Fig. 24.3 D) is conclusive

Treatment ● Uncomplicated cysts should be excised. The excision should

include the body of hyoid bone (Sistrunk’s operation) ● Infected cysts may have to be incised under antibiotic

coverage to let out the pus followed by excision at a later date. Incision of infected cyst has a high incidence of forming a fistula (thyroglossal fistula)

● Sinus or fistula requires excision

Lingual Thyroid

Incidence and Aetiology ● Occurs due to the failure of descent of the thyroid tissue

from its place of origin at the junction of anterior two-thirds and posterior third of the tongue

● The normal thyroid is absent in the neck

FIGURE 24.2 Path of descent of thyroid gland.

FIGURE 24.3A Thyroglossal cyst.

FIGURE 24.3B Infected thyroglossal cyst.

TABLE 24.1 Aetiological Classifi cation of Thyroid Disorders and Diseases

Aetiology Diseases

Congenital Persistence of duct

Thyroglossal cyst / sinus / fi stula

Failure of descent Lingual thyroid

Excessive descent Retrosternal ectopic thyroid

Infl ammatory Acute Suppurative thyroiditis

Subacute De Quervain’s thyroiditis

Subacute lymphocytic thyroiditis and post-partum thyroiditis

Chronic Hashimoto thyroiditis

Riedel’s thyroiditis

Neoplastic Benign Adenoma

Malignant Follicular carcinoma

Papillary carcinoma

Anaplastic carcinoma

Medullary carcinoma

Lymphoma

Metabolic Nontoxic goitre Colloid goitre, nodular goitre, Graves’ disease, secondary thyrotoxicosis Thyrotoxicosis

Clinical Pres entation● A globular cystic swelling in the infrahyoid region

( Fig. 24.3 A), rarely above the hyoid bone● It lies in the midline or very close to it


Clinical Pres entation● Difficulty in swallowing, with dyspnoea and occasional

bleeding● Clinical examination reveals a globular swelling

in the midline of the posterior part of the tongue ( Fig. 24.4 A)

Relevant In vestigations● Radioiodine scan reveals the presence of the thyroid tis-

sue ( Fig. 24.4 B) in the posterior part of the tongue, with no isotope activity in the neck

● MRI is us eful ( Fig. 24.4 C)

Treatment● Excision and reimplantation of the lingual thyroid in

the neck, preferably between the fibres of the sterno-mastoid muscle

Retrosternal Ectopic/Accessory Thyroid

Incidence and Aetiology ● Occurs due to excessive descent of the thyroid tissue

into the superior mediastinum, retrosternally ● Any disease of the thyroid can affect it and cause it to

enlarge and become symptomatic

Clinical P resentation A swelling in the suprasternal region with hypo- or hyper-thyroid symptoms, pressure symptoms

Relevant I nvestigations ● X -r ay of the chest ( Fig. 24.5 A ) and isotope scan

( Fig. 24.5 B) reveal the presence of the thyroid tissue

FIGURE 24.3C Thyroglossal cyst pull up on putting out the tongue.

FIGURE 24.3D Isotope scan—thyroglossal cyst.

FIGURE 24.4A Lingual thyroid (Courtesy Dr K. Dakshinamoorthy).


in the lowest part of the neck, and in the retrosternal region

● CT of the neck and thorax delineates the swelling better ( Fig. 24.5 C)

Treatment Excision of the retrosternal thyroid tissue if it shows signs of hyperactivity or enlargement with pressure effects

Suppurative Thyroiditis

Incidence and Aetiology ● Uncommon dis ease ● Occurs due to pyogenic infections and rarely due to

tuberculosis ● Often proceeds to an abscess

Clinical P resentation ● Pain, fever, dysphagia, dysphonia, cough and history of

recent upper respiratory illness ● On examination, there is a warm and tender goitre espe-

cially in the midline (isthmic) and on left side, with ery-thema of overlying skin ( Fig. 24.6 )

Relevant I nvestigations ● Leucocyte count and erythrocyte sedimentation rate

(ESR) are elevated ● Ultrasonography (US) may be needed to identify an

abscess ● Fine-needle aspiration cytology (FNAC) and culture of

pus are necessary

Treatment ● Appropriate antibiotic s may resolve the process ● Incision and drainage if abscess is formed

FIGURE 24.4B Isotope scan—lingual thyroid (Courtesy Dr S. Devaji Rao).

FIGURE 24.4C MRI—lingual th yroid.

FIGURE 24.5A Chest X-ray—retrosternal goitre.

FIGURE 24.5C CT—retrosternal goitr e.

FIGURE 24.5B Isotope scan of retrosternal thyroid.


De Quervain’s Thyroiditis

Incidence and Aetiology● Uncommon acute inflammatory disorder caused by

viral infection● The inflammatory reaction is in the form of his-

tiocytes, multinucleate giant cells and granuloma formation

● It is also called subacute granulomatous thyroiditis

Clinical Pres entation● Acute pain in the neck, with malaise and pyrexia, and

thyrotoxicosis following an episode of flu● On examination, the thyroid is enlarged, tender and

soft● Lymph nodes may be enlarged and tender

Relevant In vestigations● ESR may be elevated● Thyroid hormones may show transient elevation with

decreased TSH● Thyroid antibodie s are absent

TreatmentAnalgesics and nonsteroidal anti-inflammatory drugs (NSAIDs) will suffice, as the disease is usually self-limiting

Subacute Lymphocytic Thyroiditis and Postpartum Thyroiditis

These are considered by some as variants of Hashimoto thyroiditis but they are usually transient. Postpartum thy-roiditis (also called silent thyroiditis) occurs within a year of pregnancy and lasts several weeks or months. They are painless and present with hyperthyroidism initially, which is followed by hypothyroidism and eventually often returns to euthyroid state.

Hashimoto's Thyroiditis

Incidence and Aetiology ● An autoimmune disease of unknown aetiology also

called chronic lymphocytic thyroiditis ● Commonest cause of thyroiditis ● The thyroid is diffusely infiltrated by lymphoid and

plasma cells with destruction of thyroid follicles ● There may be family history of thyroiditis or other auto-

immune diseases such as diabetes, rheumatoid arthritis ● It may be associated with lymphoma of the thyroid

Clinical P resentation ● Varying degrees of activity of the thyroid, but hypothy-

roidism is typical ● Clinical examination reveals a diffuse goitre, firm in con-

sistency with an irregular or bosselated surface ( Fig. 24.6 A)

Relevant I nvestigations ● Thyroid hormones are decreased ● TSH levels are increased ● Antithyroid antibodies for thyroglobulin and micro-

somes are markedly elevated ● Radioisotope scan shows less activity ( Fig. 24.6 B)

FIGURE 24.6 Suppurative th yroiditis.

FIGURE 24.6A Hashimoto's th yroiditis.

FIGURE 24.6B 99Tc scan—decreased activity of hypothyroidism (Courtesy Dr K. M. Lakshmipathy).


Adenoma

Incidence and Aetiology An autonomous lesion, which may show varying grades of thyroid activity

Clinical P resentation A solitary nodule or unilateral enlargement of the thyroid gland ( Fig. 24.7 )

Relevant I nvestigations● Isotope s can may show a cold or euthyroid nodule● US reveals a solid lesion● FNAC is unreliable in differentiating from a carcinoma

Treatment Excision by hemithyroidectomy is the treatment of choice for the fear of missing malignancy

Follicular Carcinoma

Incidence and Aetiology● A well-encapsulated solitary tumour of the thyroid fol-

licles, distinct from an adenoma● The diagnosis is based on the extracapsular or venous

invasion● Histologically, this shows nuclear polymorphism and

increased nuclear to cytoplasmic ratio● Haematogenous spread can occur especially to the bones

Treatment Thyroxin administration is required for life

Riedel’s Thyroiditis

Incidence and Aetiology ● Very rare disease of unknown aetiology ● Dense fibrosis of the gland and the surrounding tissues

in the neck is predominant ● May occur in isolation or with disorders such as retroperito-

neal fibrosis, mediastinal fibrosis or sclerosing cholangitis

Clinical Pr esentation ● Rapidly increasing goitre with tracheal and oesophageal

compression ● Clinical examination shows goitre, hard and woody on

palpation

Relevant I nvestigations ● Biopsy at surgery is required ● Histopathology examination of isthmusectomy specimen

Treatment Isthmusectomy is used to release tracheal constriction

Neoplasms

Neoplasms of the thyroid are classified as shown in Algorithm 24.1.

Benign Malignant

Primary Secondary

Adenoma

Papillary Follicular

Carcinomas

Lymphomas

Undifferentiated(anaplastic)

Differentiated

Follicular PapillaryParafollicular(medullary)

Thyroid neoplasms

ALGORITHM 24.1 Classification of thyroid neoplasms.


Clinical Pr esentation ● A swelling of the thyroid gland limited to one lobe ● May present with metastases ( Fig. 24.8 ). These have large

vessels and are warm, pulsatile and noncompressible ● Lymph node swellings of the neck rarely occur

Relevant I nvestigations ● Thyroid hormones remain normal ● Serum thyroglobulin is often raised ● FNAC is useful, but unreliable in differentiating it from

an adenoma ● US shows a solid lesion

Treatment ● Total thy roidectomy is the treatment of choice ● Completion total thyroidectomy has to be done, if the

diagnosis is made after hemithyroidectomy ● Postoperative thyroxin replacement at a high suppres-

sive dose is mandatory ● 131 I ablation is warranted for any residual thyroid tissue

and distant micrometastases ● Large metastases need excision

Papillary Carcinoma

Incidence and Aetiology ● Two-thirds of all thyroid malignancies are papillary

type, and have multifocal origin

● Histologically, they show finger-like papillae and psam-moma bodies are typical

● The tumour spreads predominantly through lymphatics

Clinical P resentation ● A slow-growing (over months/years) swelling of the

thyroid gland involving one or both lobes ( Fig. 24.9 A) ● Lymph node swellings of the neck may occur

Relevant I nvestigations ● Thyroid hormones remain normal ● Serum thyroglobulin is often raised ● FNAC is useful ● US and MRI ( Fig. 24.9 B) shows a solid lesion and

enlarged lymph nodes if present

Treatment ● Total thyroidectomy with central compartment dissec-

tion is the treatment of choice ● Postoperative thyroxin replacement at a high suppres-

sive dose is mandatory ● Modified radical neck dissection if lymph nodes are

involved

FIGURE 24.7 Thyroid ade noma.

FIGURE 24.8 Metastases in the skull secondary to follicular carcinoma of thyroid.

FIGURE 24.9A Papillary carcinoma of thyroid with cervical lymph node metastases (Courtesy Dr V. Srinivasan).

FIGURE 24.9B MRI—papillary carcinoma with lymph node metastases.


Anaplastic Carcinoma

Incidence and Aetiology ● Aggressive tumours believed to arise from unrecognized

differentiated tumours ● Common in endemic areas and present in the elderly

over the age of 60

Clinical Pr esentation A hard woody enlargement of the thyroid ( Fig. 24.10 ) fixed to the surrounding structures

DD: Riedel’s thyroiditis, lymphoma, calcified lesions

Relevant I nvestigations FNAC or open biopsy is confirmatory

Treatment Excision of tumour as much as possible especially the isth-mus, with radiotherapy

Medullary Carcinoma

Incidence and Aetiology ● Malignancy derived from C cells ● Incidence of 5–10% of thyroid malignancies ● They produce calcitonin to detectable levels in blood ● Majority of them occur sporadically and the rest have a

familial tendency ● Familial medullary carcinoma has some peculiar features:

● Autosomal domina nt inhe ritance ● Multifocal origin ● Can be associated with pheochromocytoma and

parathyroid hyperplasia (multiple endocrine neopla-sia [MEN] 2 syndrome)

Clinical Pr esentation ● A lump in the neck with lymph node ( Fig. 24.11 ) or

distant metastases ● Diarrhoea can occur due to high levels of calcitonin ● Familial history is elicited

Relevant I nvestigations● Plasma calcitonin and carcinoembryonic antigen

(CEA) may be elevated● FNAC of the thyroid mass or cervical lymph nodes is

necessary● Whole body isotope 99 Tc scan is useful in identifying

distant metastases● Plasma and urine metanephrine, urinary catechol-

amines to detect pheochromocytoma● Serum parathormone to detect hyperparathyroidism● Ret test (genetic screening for ret point mutations) for

MEN 2

Treatment● Total thyroidectomy and thyroxin replacement

Local recurrence requires surgery and distant metastases radiotherapy.

Lymphoma

Incidence and Aetiology● Extremely rare in the thyroid (less than 1% of the thy-

roid malignancies)● Typically, affects the elderly females● Longstanding Hashimoto thyroiditis is the only known

risk factor

Clinical P resentation● A rapidly growing nodule● Hard woody enlargement ( Fig. 24.12 ) of the thyroid

fixed to the surrounding structures, if Hashimoto thy-roiditis pre-exists

● Cervical lymph nodes may be palpableDD: Riedel’s thyroiditis, anaplastic carcinoma

Relevant I nvestigationsFNAC or open biopsy is confirmatory

TreatmentConcurrent chemotherapy and radiation is the treatment of choice

FIGURE 24.10 Anaplastic carcinoma of thyroid (Courtesy Dr R. Rajaraman).

FIGURE 24.11 Medullary carcinoma of thyroid with lymph node metastases (Courtesy Dr R. Rajaraman).


Nontoxic Goitre

Incidence and Aetiology An enlargement of the thyroid is named goitre

It can present as:1. Diffuse goitre: A simple swelling of the thyroid caused

by hyperplasia due to stimulation of the thyroid by raised levels of TSH, with female preponderance in the ratio of 6:1

● The swelling may be transient as in physiological goitre or permanent as in colloid goitre

● The c auses a re:● Iodine deficiency in endemic areas (gland’s attempt

to extract iodine from a diet insufficient in iodine)● Physiologic demands (puberty and pregnancy,

following severe illness, physical and emotional stress)—raised TSH concentration, stimulation of thyroid by beta-human chorionic gonadotropin (HCG) (structurally similar to TSH)

● Drugs and dietary factors (e.g. goitrogens—drugs and chemicals found in foods such as cabbage)

● Enzyme malfunction in the thyroid (dyshormono-genetic goitre) (peroxidase deficiency, as part of Pendred syndrome—associated with deafness)

2. Multinodular goitre: The constant stimulation and nonuniform regression causes multinodularity. Five to ten per cent of multinodular goitres undergo malignant change. Chronic thyroiditis or toxic goitre after pro-longed treatment with drugs or after radioiodine ablation may present as a nodular goitre

Clinical Pres entation● Diffuse goitre:

● A painless enlargement of the thyroid, with gradual progression

● Clinical examination may reveal uniform enlarge-ment ( Fig. 24.13 ) of the thyroid with smooth surface

● Multinodular goitre:● Painless enlargement with gradual progression● Dyspnoea (due to compression of the trachea) and

dysphagia (due to compression of the oesophagus)● Clinical examination may reveal a solitary nodule

( Fig. 24.14 ) or multiple nodule s ( Fig. 24.15 )● Trachea may be shifted from the midline due to

uneven enlargement of the gland● There may be a retrosternal extension larger than the

goitre in the neck

FIGURE 24.12 Non-Hodgkin’s lymphoma of thyroid (Courtesy Dr R. Rajaraman).

FIGURE 24.13 Diffuse enlargement of thyroid.

FIGURE 24.14 Solitary thyroid nodule.

FIGURE 24.15 Multinodular g oitre.


● Distended veins may be seen due to obstruction of the superior vena caval system

● Regional lymphadenopathy and hoarseness of voice suggest malignant change

Relevant In vestigations● Thyroid function tests to establish the activity of the

thyroid (euthyroid, hyperthyroid or hypothyroid)● US identifies cysts from solid lesions, size and extent of

the goitre● X - ray of the soft tissues of the neck is useful to identify

tracheal shift or compression● FNAC is indicated in doubtful lesions to rule out malig-

nant change● MRI ( Fig. 24.16 ) and isotope scans are useful in identi-

fying retrosternal extensions

Treatment● No treatment is required for small euthyroid goitres● Hormone supplements for hypothyroid goitre● Surgery is required for hyperthyroid and pressure

causing multinodular goitres:● Hemithyroidectomy for hyperthyroid goitres (uni-

lobular lesions or solitary nodule of one lobe)● Total thyroidectomy for bilobar multinodular goitre to

prevent pressure effects and for fear of suspected malig-nant transformation, followed by life-long thyroxin

Thyrotoxicosis

Incidence and Aetiology Thyrotoxicosis is a symptom complex, which results from peripheral actions of increased levels of circulating

thyroid hormones, with a female preponderance. The causes are: ● Diffuse enlargement of thyroid: Primary thyrotoxi-

cosis or Graves’ disease (an autoimmune disease with autoantibodies against TSH receptors that act as long-acting thyroid stimulators—LATS)

● Toxic multinodular goitre: Plummer syndrome ● Toxic solitary thyroid nodule

Secondary thyrotoxicosis: The differentiating fea-tures of primary and secondary thyrotoxicosis are given in Table 24.2 .

Clinical P resentation ● Graves’ disease: Smooth generalized enlargement of

the thyroid gland ( Fig. 24.17 ) with ophthalmic features (Graves’ ophthalmopathy) and dermatologic symptoms (Graves’ dermopathy). Associated autoimmune diseases (e.g. vitiligo, rheumatoid arthritis)

● Toxic multinodular goitre: Multinodular thyroid swell-ing, with cardiac arrhythmias and heart failure

● Toxic solitary thyroid nodule: A solitary swelling in one lobe of thyroid, with cardiac manifestations

Relevant I nvestigations ● Thyroid function tests to establish its overactivity ● Thyroid autoantibodies may be present in autoimmune

disorders

FIGURE 24.16 MRI—diffuse goitr e.

TABLE 24. 2 Differentiating Features of Primary and Secondary Thyrotoxicosis

Primary thyrotoxicosis Secondary thyrotoxicosis

Usually in the young (15–45 years) women

Occurs later in life between 45 and 65 years

Symptoms appear before swelling and are more severe

Symptoms are less severe and appear long after the swelling

Thyroid is uniformly enlarged and smooth

Thyroid is larger in size, nodular and asymmetric

Tremors, exophthalmos and eye signs are common

Cardiac symptoms are common

FIGURE 24.17 Graves’ dis ease.


● Radioisotope scans show activity of nodule ( Figs. 24.18, 24.19 A a nd B )

Treatment● Antithyroid drugs are required to manage thyrotoxicosis● Beta-blockers are useful in managing the effects of T 4

on the sympathetic system●

131 I radio ablation therapy is a convenient and perma-nent therapy

● Thyroidectomy is indicated when the enlargement is huge and causes pressure effects, and also for toxic mul-tinodular goitre. Failure of compliance to treatment is also an indication for surgery

24.5 SYMPTOMS O F THYROID DISEASES The presenting complaints of patients with thyroid diseases are:● Swelling in the region of the thyroid● Sinus or fistula in the midline of the neck● Pressure s ymptoms● Cardiac symptoms (thyrocardiac disease)● Ophthalmic s ymptoms ( ophthalmopathy)● Dermatologic s ymptoms ( dermopathy)● General symptoms of thyroid malfunction● Swellings in other areas of the neck or elsewhere

(metastases)

Analysis of Symptoms

Swelling in the Region of the Thyroid The commonest presentation of a thyroid disorder is in the form of a swelling in the lower part of the neck, in the region of the thyroid, just lateral to the midline. The swell-ing is in different forms:● Single nodular swelling: Solitary thyroid nodule● Multiple nodular swellings (usually on both sides):

Multinodular goitre● Smooth enlargement of the thyroid: For example

Graves’ disease (need not be symmetrical)● Smooth globular swelling in the midline: Thyrog lossal cyst

Sinus o r F istula i n t he M idline o f N eck Thyroid pathologies can present in the form of a discharg-ing sinus or fistula (e.g. thyroglossal fistula).

Pressure Sym ptoms Since thyroid gland is located in the neck closely related to the structures such as trachea and oesophagus, pressure symptoms may be caused by:● Goitres of massive size● Goitres with large intrathoracic extension● Chronic t hyroiditis● Infiltration by thyroid malignancies

And the symptoms related to pressure on the neighbour-ing structures are:● Dyspnoea (choking sensation with cough)—pressure on

trachea:● Positional dyspnoea (on flexing the neck forwards or

laterally)● Nocturnal dyspnoea (on lying flat at night)

● Dysphagia —pressure on oesophagus● Dysphonia (hoarseness of voice)—pressure or infiltra-

tion of recurrent laryngeal nerve● Stridor (whistling sound)—narrowing of trachea due to

pressure or malignant infiltration of trachea

Cardiac S ymptoms Cardiac symptoms are associated with thyrotoxicosis. Hypermetabolism of the peripheral tissues increase both

FIGURE 24.18 99Tc scan—diffuse toxic goitre (Courtesy Dr K. M. Lakshmipathy).

FIGURE 24.19B 99Tc scan—cold nodule (Courtesy Dr K. M. Lakshmipathy).

FIGURE 24.19A 99Tc scan—hot nodule (Courtesy Dr K. M. Lakshmipathy).


area is well demarcated from the normal skin with a character-istic appearance. It is raised, thickened, has a peau d’orange appearance, may be pruritic and hyperpigmented. Dermal changes may be accompanied by clubbing ( thyroid acropachy )and signs of other associated autoimmune diseases.

In hypothyroidism (e.g. autoimmune) there is a general-ized myxoedema.

General Sym ptoms of Th yroid M alfunction The general symptoms vary according to the activity of the thyroid gland and the effect of the thyroid hormones on tissues. Excessive activity is collectively termed hyperthy-roidism and reduced activity hypothyroidism .

the metabolic and nonmetabolic (heat loss) circulatory load, whereas direct effect of the thyroid hormones on the myocar-dium increases the force, velocity and rate of ventricular con-traction. The symptoms and signs are tabulated in Table 24.3 .

Ophthalmic Sym ptoms The eyes may be involved in thyrotoxicosis, possibly due to a cross reaction between thyroid stimulating antibodies in the eye muscles and intra-orbital tissues. The ocular signs are thought to result from sympathetic overstimulation, and subside when thyrotoxicosis is corrected. The symptoms and signs of eye involvement are tabulated in Table 24.4 .

TABLE 24.3 Symptoms and Signs of Cardiac System Associated with Thyrotoxicosis

Symptoms Signs

• Palpitation • Precordial

chest pain

• Sinus tachycardia • Tachydysrhythmias • Atrial fi brillation • High-output cardiac failure • Digitalis resistant cardiac failure

TABLE 24.4 Symptoms and Signs of Eye Involvement Related to Thyrotoxicosis

Symptoms Signs

• Double vision • Grittiness in the eye • Protrusion of eyes

(exophthalmos)

Grade 1: Mild

• Upper sclera visible due to eyelid retraction • Lid lag on looking down • Characteristic stare with widened palpebral fi ssures

Grade 2: Moderate

• Exophthalmos and failure to wrinkle the brow on upward gaze

Grade 3: Severe

• Ophthalmoplegia (palsy of superior and lateral recti and oculomotor nerves) • Congestive oculopathy (chemosis, conjunctivitis, periorbital swelling, corneal ulcerations, optic neuritis,

optic atrophy)

Grade 4: Progressive

• Progressive protrusion of eye balls (malignant exophthalmos)

Note

The term exophthalmos is used in thyrotoxicosis, which is bilateral and the term ‘proptosis’ denotes protrusion of the eyes due to numerous other intra-orbital and periorbital causes and is often unilateral. Werner’s classification has grades 0–6.

Dermatologic Sym ptoms Dermatologic symptoms are common in Graves’ disease (Graves’ dermopathy), and usually manifest over the dorsum of feet and legs, and is called pretibial myxoedema . The affected

Note

Goitre with hypothyroidism may occur in thyroiditis, dyshor-monogenesis, multinodular goitre and drug-induced goitre.

The symptoms of thyroid malfunction are tabulated in Table 24.5 .

Pain Pain is a very rare accompaniment of the thyroid patholo-gies excepting in those of infective inflammatory aetiology such as de Quervain’s thyroiditis.

The symptom analysis is tabulated in Table 24.6 .

Note

Endemic, sporadic, drug-induced and multinodular goitres, solitary thyroid nodule, early thyrotoxicosis and Hashimoto thyroiditis may present without any symptom excepting a swelling in the thyroid.


TABLE 24.5 Symptoms of Thyroid Malfunction

Symptom Hyperthyroidism Hypothyroidism

Change in weight and appetite Weight loss in spite of excessive appetite Weight gain in spite of decreased appetite

Tolerance to temperature Intolerance to heat Intolerance to cold

Neuromuscular Nervousness, anxiety, irritability, insomnia, tremors and muscle weakness

Lethargy, slowing of intellectual and motor activity, myalgia, fatigue

Cardiovascular Palpitations, dyspnoea on exertion, chest pain Bradycardia, dyspnoea, pedal oedema

Ophthalmic Poor visual acuity, double vision, grittiness in the eye Periorbital puffi ness

Gastrointestinal Frequent passage of stools Constipation

Gynaecological Oligomenorrhoea, amenorrhoea Menorrhagia

Dermatological Warm and moist skin, fi ne silky hair Dry skin, loss of hair especially outer eyebrows

Orthopaedic Arthralgia

Voice Coarse voice

TABLE 24.6 Analysis of Symptoms of the Thyroid Disorders

Lesion

Incidence

Rate of Growth Pain Other features Age

F:M ratio

Simple Goitre

Diffuse goitre 5–20 5:1 Very slow Painless

Multinodular goitre 20–40 6:1

Thyroiditis

Acute and sub-acute thyroiditis

30–50 2:1 Rapid Pain, fever Preceding URI, mild toxicity

Chronic

Hashimoto thyroiditis At menopause Variable Mild pain Hypothyroid, associated autoimmune diseases

Riedel’s thyroiditis 40–70 Rare Slow Painless Early pressure symptoms

Diffuse toxic goitre 20–40 8:1 Thyrotoxicosis

Neoplastic

Adenoma 20–40 4:1 Slow Usually painless

Papillary carcinoma 30–50 4:1 Pain in late stages

Follicular carcinoma 40–60 3:1 Bone pain (metastases)

Anaplastic carcinoma 50–70 1.5:1 Rapid Pain present Early distant metastases

Medullary carcinoma (nonfamilial)

50–70 3:1 Family history, MEN 2, metastases

Lymphoma 50–70 1:3 (rare) Pain in late stages Preceding Hashimoto thyroiditis


24.6 CLINICAL EV ALUATION

Eliciting History

General P articulars● Age: Thyroglossal cyst is common in young age; simple

goitre is more common at puberty and malignancies are more common in the elderly

● Sex: Most thyroid disorders are common in females● Place of residence: Iodine deficiency goitres are

endemic in some areas such as Himalayas, Nilgiris in India and mountainous areas in the world. There is a higher incidence of thyrotoxicosis, thyroiditis, thyroid tumours in these areas

Questions to be Addressed to the PatientSwelling

● Duration of swelling: When did the patient first notice the swelling?

This will give the duration of the present illness—short duration represents acute pathology such as acute infections (e.g. De Quervain’s thyroiditis), and car-cinomas (e.g. anaplastic carcinoma) or a haematoma in a pre-existing lesion and long duration indicates chronic pathologies such as simple colloid goitre, mul-tinodular goitre, chronic thyroiditis and benign tumours such as adenoma. Swellings presenting soon after birth or in young age may be congenital in aetiology (e.g. goitres of cretinism, thyroglossal cyst, lingual thyroid)

● Site of swelling: Where did the patient notice the swell-ing first?

Tumours or solitary cysts develop as unilateral swelling in one of the lobes, i.e. on one side of the neck or midline (e.g. lesion in the isthmus). Bilateral develop-ment of swelling of the thyroid is seen in other causes of goitre, though this may be symmetrical or asymmetrical

● Mode of onset: Was it a sudden event or gradual in developing, and was there any trauma preceding the swelling?

Stress and anxiety may precipitate thyrotoxic goitre. Viral upper respiratory infection usually precedes De Quervain’s thyroiditis. Trauma to the neck may lead to a haematoma

● Variation in size: Does the lump remain the same in size always or shows some variation?

Non-neoplastic thyroid swellings may show regres-sion in size, in response to the therapy, but neoplasms show a steady increase in size. The rate of progression in size is a useful indicator, as rapid progression in size represents malignancy (e.g. anaplastic tumours), slow progression indicates a benign disease (e.g. adenoma), and a sudden progression may indicate haemorrhage in a cyst and a change from slow to rapid progression indicates malignant change or dedifferentiation of a dif-ferentiated cancer

Discharge from External Sinus / Fistula

● Nature of discharge: Was or is the swelling painful and does or did it discharge any fluid at any time?

Burst thyroglossal abscess discharges pus through the overlying skin, in the form of a sinus or fistula (e.g. thyroglossal sinus or fistula)

● History of previous surgery or trauma: Did the patient undergo any surgery in the neck or did he sus-tain any injury?

Incision and drainage of thyroglossal cyst is known to result in a sinus or fistula. Thyroglossal fistula is also known to recur after surgery

Pressure Symptoms

● Dyspnoea: Does the patient have difficulty in breath-ing? If so, is it related to any posture?

Any thyroid swelling can press the trachea or even compress it almost circumferentially and cause dif-ficulty in breathing. Since, thyroid swellings are pre-dominant on the sides of the trachea, the dyspnoea is pronounced when the patient lies on his or her sides or on the side of a unilateral goitre. Severe narrowing of the trachea can create noise during breathing, called stridor. Malignant swellings infiltrate the trachea and cause the same effect

● Dysphagia: Does the patient have difficulty in swallowing? A thyroid swelling due to its proximity to the oesoph-

agus can press the oesophagus from the sides and cause dysphagia, more so when it is malignant

● Hoarseness: Does the patient complain of change in voice?

Hoarseness of voice is seen with patients with hypo-thyroidism and also when malignancies infiltrate or press on the recurrent laryngeal nerves which run in the tracheoesophageal grooves. Longstanding multinodular goitre or Hashimoto thyroiditis developing hoarseness should indicate malignant change

Cardiac Symptoms

● Cardiac symptoms: Does the patient complain of symptoms such as palpitations, chest pain, swelling of the feet, related to cardiac system?

Cardiac symptoms such as palpitations and chest pain can, and those of cardiac failure such as dyspnoea, pedal oedema etc., manifest with thyrotoxicosis and may indicate the activity of the lesion

Ophthalmic Symptoms

● Ophthalmic symptoms: Does the patient have any symptom related to the eyes?

Development of symptoms related to the eye such as diplopia, diminution of visual acuity may be indicative of thyrotoxicosis


feel nodular; recurrence of goitre may recur after hemi / partial thyroidectomy)

● Past history: Was there any other illness in the past, which required any treatment? Was there exposure to radiation?

If the patient had suffered any other illness in the past, which required any treatment (e.g. radiation to head, neck or thymus in the childhood can predispose to thyroid malignancy)

● Family history: Has any other family member suf-fered from a similar illness or had any treatment?

Many thyroid diseases run in families (e.g. iodine or enzyme deficiency, primary thyrotoxicosis, medullary carcinoma, various autoimmune disorders associated with Hashimoto thyroiditis)

● Personal history: Questions regarding personal habits: Personal habits such as smoking and drinking alco-

hol do not have any direct relationship to thyroid pathol-ogies, but dietary history has a very great relevance (e.g. iodine deficient diet, goitrogenics in diet)

● Any other relevant question: This is for the examiner (clinician) to decide likely exposure to tuberculosis

Physical Examination

Thyroid The examination of the patient should be carried out in the following steps:1. Inspection2. Palpation3. Percussion4. Auscultation Pre-requisites ● Position of the patient: Patient should be made to sit

comfortably on a chair, with his or her arms down and the neck extended

● Position of the examiner: The examiner should sit com-fortably and the patient’s face and neck should be at the examiner’s eye level ( Fig. 24.20 )

● Adequate illumination is necessary● Adequate knowledge of the thyroid and its related anat-

omy is mandatory

Inspection

The examiner should never be hasty to touch the patient with an urge to make the diagnosis. Inspection forms the first part of the examination. The points to note during inspection are:● Location or site of swelling: The location of the swelling

is observed in relation to the anatomical landmarks, both from the front and sides. Swelling located in the region of the thyroid, or in the path of descent of the thyroid (e.g. thyroglossal cyst—suprahyoid or infrahyoid, retroster-nal goitre). In obese and short-necked individuals, the

Dermatologic Symptoms

● Skin changes: Does the patient complain of any changes in the skin?

Variety of dermal changes are seen both in hyperthy-roidism and hypothyroidism

General Symptoms

The examiner should be familiar with the general symptoms of thyroid diseases and should direct questions in relation to those.

Swellings in Other Parts of the Neck

● Swellings in the neck: Does the patient complain of any other swelling in the neck?

Lymph node swellings can occur as metastatic nodes secondary to thyroid malignancies or as part of lym-phoma of the thyroid

Pain

Pain is an uncommon symptom of thyroid disorders. ● Nature of pain: Was or is the swelling painful and how

severe is it? Acute and subacute thyroiditis are associated with

the pain of varying intensity and nature

● Duration of pain: Was the pain present along with the onset of the swelling or did it precede or follow the appearance of the swelling?

Pain and prodromal symptoms suggest viral thyroid-itis, and development of pain in a pre-existing swelling suggests malignancy, or haemorrhage in a cyst. Pain may follow FNAC

● Precipitating factors: What is aggravating the pain? Pain may be felt only on deglutition. Pain on move-

ments of the neck may indicate infiltrating malignancies of the thyroid

● Radiation of pain: Is there any radiation of pain? Pain of thyroid pathology may radiate to the ears or jaws

Other Related Questions

● Association of fever: Is or was it associated with fever? Associated fever may indicate an infective pathology

(e.g. suppurative or viral thyroiditis)

● Appetite and weight: Is there any change or loss of appetite and weight in the course of illness?

Loss of appetite and weight are indicative of illnesses such as malignancies. Increased appetite and weight loss is seen in hyperthyroidism and the reverse in hypothyroidism

● Treatment for the illness: Has any treatment been given for the present illness?

The information of any treatment received in the past for this illness will give a clearer picture of diagnosis (e.g. intake of goitrogens, antithyroid drugs can alter the signs and symptoms; treated primary toxic goitre may


thyroid gland is more visible by Pizillo’s method (the patient should place his or her clasped hands behind his or her head on the occiput, and push back against them with his or her head) ( Fig. 24.21 )

● Number of swelling: The number gives a clue to diag-nosis: ● Solitary swellings (e.g. thyroglossal cyst in the mid-

line, solitary thyroid nodule lateral to the midline) ● Multiple swellings: Unilateral or bilateral (e.g. mul-

tinodular goitre) ( Fig. 24.15 ) ● Shape of the swelling: Shape is three dimensional, but

can be described in descriptive terms such as butterfly shaped, oval, globular, irregular, etc. ● Symmetrically enlarged butterfly shaped on both

sides (e.g. diffuse goitre) ● Asymmetrical:

- Unilateral, single, oval or globular (e.g. solitary nodule)

- Multiple nodules (e.g. multinodular goitre) - Irregular swellings (e.g. multinodular goitre,

malignancies) ● Size of the swelling: Lumps of thyroid origin have three

dimensions and all the three should be visually esti-mated and noted down

● Skin over the swelling: Careful attention has to be given to the skin over the swelling to note the following: ● Colour: Redness indicates acute inflammation (e.g.

acute thyroiditis) ● Texture of skin: Shiny glistening skin over the swell-

ing indicates the stretching of skin, oedema of the skin over the swelling (e.g. infected cyst). Tethering of skin suggests malignancy

● Changes on the surface: Prominent scars (e.g. indicate previous surgery), fistula (e.g. thyroglos-sal fistula)

● Prominent veins: Engorgement of the veins in the subcutaneous plane may indicate fast-growing tumour creating venous blockage (e.g. large thyro-megaly obstructing the superior vena caval system) ( Fig. 24.22 A). This can be confirmed by asking the patient to lift both arms so as to touch the sides of his or her face, and maintain for a min-ute ( Fig. 24.22 B). Prominence of veins indicates superior vena caval obstruction at the thoracic outlet ( Pemberton’s sign ). When the intrathoracic extension is large and occludes the thoracic outlet ‘ thyroid cork phenomenon ’, the face looks con-gested, swollen and unhealthy called ‘facial plethora’

● Horner syndrome ( Fig. 24.22 C) suggests involve-ment of sympathetic trunk. It is characterized by: - Slight sinking of the eyeball into the orbit (enoph-

thalmos due to paralysis of Muller’s muscle) - Drooping of upper eyelid (pseudoptosis due to

sympathetic trunk paralysis) - Contraction of pupil ( myosis due to paralysis of

sympathetic fibres)

FIGURE 24.20 Examination of thyroid gland.

FIGURE 24.21 Pizillo’s me thod. FIGURE 24.22A Prominent veins due to thoracic outlet obstruction by large thyroid swelling.


smooth and regular, rough and irregular or in any combination:● Smooth surface indicates cystic swellings, diffuse

goitre● Irregular or lobulated surface may indicate multi-

nodularity● Margin of the swelling:

● The edge or margin may be flattened or projecting, well defined or ill defined

● Well-defined or circumscribed margins indicate benign swellings

● Ill-defined margins indicate poorly differentiated malignancies (e.g. anaplastic carcinoma)

If the lower margin of the goitre is not seen it should be looked for during deglutition.● Movements: Since the thyroid is enclosed by the pretra-

cheal fascia attached to the oblique line on the thyroid cartilage and the arch of cricoid cartilage, the swelling moves w ith de glutition ( Fig. 24.22 D)

FIGURE 24.22B Method of eliciting Pemberton’s sign.

FIGURE 24.22C Horner s yndrome.

FIGURE 24.22D Thyroid moving up on deglutition.

- Absence of s weating (a nhidrosis) - Flushing of face and nasal congestion due to

vasodilatation● Surface of the swelling: The surface of the swell-

ing provides some indication of its aetiology, and is described in easily understandable terms such as

Note

● Subhyoid bursa, pretracheal and prelaryngeal lymph nodes and swellings of larynx and trachea (e.g. laryngo-cele), which are also enclosed in the pretracheal fascia will move with deglutition.

● Thyroglossal cyst moves up with protrusion of the tongue.● A goitre which is very large or fixed or with large

retrosternal component may not move with deglutition.

Palpation

Patient continues to be seated with arms down and neck now slightly flexed, instead of the extended position used for inspection and the face rotated to the side under palpa-tion to relax the sternomastoid muscle on that side.● Palpation of the skin over the swelling:

● Warmth: In abscess and acute thyroiditis the thy-roid feels warm, when felt by the back of the hand

● Tenderness: Thyroid swelling is tender to palpation in thyroiditis and abscess, elicited by gentle palpation

● Skin involvement is tested by two methods: - Gliding test ( Fig. 24.23 )—the skin is rolled over

the swelling to see whether it is fixed or not


- Pinching test ( Fig. 24.24 )—the skin is pinched with the thumb and the index finger to see its adherence to the lump

● Palpation of the thyroid gland: Examination should be done both from the front and from behind:● From behind: The examiner should go behind the

seated patient and the patient is asked to flex the neck slightly. The examiner should keep both the hands on the sides of the neck, with the thumbs on the nuchal line and the pulps of the fingers on the lobes of thyroid. The gland is palpated by running the pulps of the fingers on them ( Fig. 24.25 )

● From front: The examiner should stand in front of the seated patient, and each lobe is palpated with the thumb, right thumb for the right lobe and left thumb for the left lobe. Next, the lobes are pushed individu-ally to one side for palpation ( Lahey’s method ). For palpating the left lobe, the examiner should push the lobe laterally by the left hand, and the lobe is pal-pated with the right hand ( Fig. 24.26 ). For the right lobe, the lobe is pushed laterally by the right hand

FIGURE 24.23 Gliding test for assessing skin involvement.

FIGURE 24.24 Skin pinching test for assessing skin involvement.

FIGURE 24.25 Examination of thyroid from behind.

FIGURE 24.26 Lahey’s method of examination of thyroid.

and is palpated with the left hand. A unilateral goitre can also be palpated when standing on the opposite side of the patient

The following are noted; inspection findings of number, shape etc. are confirmed:● Site: It is determined whether the whole of the thyroid is

enlarged or there is a localized swelling● Exact size: The exact size is determined in two direc-

tions (measured by tape— Fig. 24.27 A), and also the cir-cumference of the neck will help ( Fig. 24.27 B)

● Surface: Assessed by running the pulp of the examin-ing fingers over the swelling. Otherwise, the patient may be asked to swallow while palpating the gland with a thumb, with the gland between the thumb and other fin-gers (Crile’s method— Fig. 24.28 )

● Margins: Determined by running the index finger along the margins ( Fig. 24.29 ). When the sternomastoid mus-cles are over the thyroid swelling, the muscles can be displaced laterally by the palpating fingers or by the other hand. Starting high in the neck to ensure that a high-placed goitre is not missed, the fingers are moved


laterally starting from the cricoid cartilage, then to the upper border of the isthmus inferior to it and then along the borders of the thyroid. The fingers are moved in a circular and rubbing movement. Then, with the hands held steady, the patient is asked to swallow repeatedly

● Palpation of lower border of the thyroid: The lower bor-der is generally felt in the neck close to the suprasternal notch. This is determined by placing the index finger on the lower border of the gland ( Fig. 24.30 ). When it is not felt, the neck should be hyperextended. If still not palpa-ble, the patient is asked to swallow and if the lower border is now felt, it indicates small amount of retrosternal exten-sion. In large extensions the lower border is never felt

FIGURE 24.27A (A) Measuring the vertical enlargement of thyroid. (B) Measuring the circumference of neck.

A B

FIGURE 24.28 Crile’s me thod.

FIGURE 24.29 Feeling the margins of the thyroid swelling.

FIGURE 24.30 Palpating the lower border of thyroid to determine.


● Consistency: This is determined by applying firm pres-sure on the swelling (e.g. benign tumours are firm and malignant tumours are hard in consistency)

● Mobility of overlying skin: Skin over the swelling is pinched up. If it is indurated and fixed, it cannot be pinched up, and it may indicate an underlying malignancy or inflammation. Thyroglossal cyst moves up with protrusion of the tongue and an upward tug is felt if it is held back between the fingers pinching above it ( Fig. 24.31 )

● Plane: Patient is asked to push chin down against resis-tance thus causing contraction of both sternocleido-mastoids and strap muscles. Thyroid swellings, lymph nodes etc. that lie deep to these muscles become less prominent

● Palpation for its mobility: The swelling is held between the thumb and index finger and moved in all directions. Lack of mobility indicates fixity to deeper structures (e.g. malignant tumours)

● Fixity to trachea or larynx: Fixity to trachea or larynx leads to differential mobility in transverse direction but not in vertical direction

● Fixity to sternomastoid: Fixity to sternomastoid is checked by asking the patient to swallow while pinching the relaxed muscle and feeling the pull on the muscle by the adherent thyroid

● Kocher’s test: This test is used to detect narrowing of the trachea due to the pressure effect of the goitre. By appli-cation of pressure on both lobes of a goitre, the trachea gets further narrowed and causes the characteristic noise of breathing ‘ stridor ’ ( Fig. 24.32 )

● Testing the surrounding structures: ● Tracheal deviation: When the thyroid swelling is

unilateral and the trachea is visible, the index fin-ger and the ring finger are kept on the heads of the clavicles and the middle finger is run along the tra-chea and its rings starting as high as possible, till it reaches the suprasternal notch. If the finger reaches the midline, there is no tracheal shift. If the finger reaches close to one of the clavicular heads, the tra-chea is considered deviated to that side ( Fig. 24.33 ). When the trachea is covered by the thyroid tissue,

the trachea is felt in the midline at the suprasternal notch, and the deviation assessed.

FIGURE 24.31 Feeling of upward tug on thyroglossal cyst.

FIGURE 24.32 Kocher’s test for stridor.

FIGURE 24.33 Method of palpating the trachea.

Note

A large isthmic nodule or a retrosternal extension with gross deviation can make it difficult to palpate the trachea. Auscultation for tracheal sounds helps to locate the trachea.

● Muscles: Sternomastoid muscles may become thinned out due to large thyroid swellings stretch-ing them. The bulk and the power can be tested by asking the patient to turn the head to one side against resistance, applied by the examiner’s hand ( Fig. 24.34 ).

● Arteries: Normally, the common carotid artery is felt at the level of the upper border of thyroid cartilage over Chassaignac tubercle on the transverse pro-cess of C6 vertebra ( Fig. 24.35 ). This gets displaced posteriorly by a benign thyroid swelling. Malignant swellings of thyroid may infiltrate the carotid sheath and the carotid pulse may become impalpable (Berry’s sign) .


FIGURE 24.34 Feeling the bulk and power of sternomastoid muscle.

FIGURE 24.35 Feeling the carotid pulse.

FIGURE 24.36 Auscultation of thyroid for bruit.

Note

● In individuals with thin long neck, the cricoid cartilage and thyroid gland lie at a higher level and the goitre may be missed or the size is overestimated.

● In elderly individuals with kyphosis or emphysema, the cricoid cartilage and thyroid gland lie very low almost hidden by the sternum and the size may be underesti-mated.

● A low-lying goitre may be detected only on palpating the lower anterior neck during swallowing.

● The pyramidal lobe may lie lateral to the midline and may be mistaken for an enlarged lymph node.

● If nodules are felt only during swallowing, they should be trapped between the fingers and felt after the act of swallowing is complete for details.

● The upper pole of thyroid lobe is felt by pinching it up with the thumb and index finger.

● A pad of fat in the anterolateral neck especially in the obese may resemble goitre but it does not move with deglutition (pseudogoitre).

Percussion

Percussion over the manubrium sterni will give a dull note when retrosternal thyroid or any other retrosternal mass (DD) is present.

Auscultation

● Auscultation over the thyroid, swelling may demon-strate:● A bruit ( Fig. 24.36 ), indicating increasing vascular-

ity, a feature of malignant tumours● A continuous low-pitched venous hum over the goitre

in Graves’ disease● Tracheal breath sounds help to locate trachea and

any shift in its position● Auscultation over the carotid artery may demonstrate:

● A bruit indicating compression

Relevant AreasFace

The face is examined for the signs of thyroid malfunction:● Hyperthyroidism:

● Characteristic stare with widened palpebral fissures (frightened facies)

● Failure to wrinkle the brow on upward gaze● Hypothyroidism:

● Dull e xpressionless f ace● Rough, dry and doughy skin● Sparse hair (loss of outer third of eyebrows)● Puffiness of the face with pouting of lips

Scalp

● Checked for metastases (warm, pulsatile, smooth well-defined lump)

Eyes

● HyperthyroidismThyroid ophthalmopathy is usually graded as mild, moderate, severe and progressive. Werner’s


classification has grade 0–6. They appear in the following order: 1. Signs of mild ophthalmopathy:

(a) Infrequent blinking, staring look and widened palpe-bral fissures (Stellwag’s sign)

(b) Lid retraction: Due to spasm of Muller’s muscle (a smooth muscle adjoining the levator palpebrae supe-rioris), the upper eyelid remains at a higher level so that the sclera is visible above the iris (Dalrymple’s sign) ( Fig. 24.37 A)

(c) Lid lag: The patient’s head is stabilized with exam-iner’s left hand and the patient is asked to follow the examiner’s right index finger which is slowly moved downwards from patient’s eye level. The upper eyelid lags behind the pace of movement of the eyeball exposing the upper sclera (von Graefe’s sign) ( Fig. 24.37 B)

2. Signs of moderate ophthalmopathy: (a) Exophthalmos: The eyeball is pushed forward,

exposing the sclera both above and below the iris ( Figs. 24.37 C and D). Mild exophthalmos is detected by the examiner standing behind the patient, with the patient’s head tilted backwards, and the eyeballs vis-ible (Naffziger’s sign) ( Fig. 24.37 E)

(b) Due to exophthalmos, the patient can look up without wrinkling the forehead even when the face is inclined downwards (Joffroy’s sign) ( Fig. 24.37 F)

(c) Upper eyelid eversion is difficult or absent in exoph-thalmos (Gifford’s sign) but is easy in proptosis

3. Signs of severe ophthalmopathy: (a) Failure for convergence: Patients have diplopia and

are unable to converge their eyes. The patient’s head is stabilized with examiner’s left hand and examiner’s right index finger is moved from a distance towards the root of the patient’s nose between the eyes. The patients are asked to keep looking at the approach-ing fingertip and their ability to converge their eyes is looked for. (Moebius’s sign) ( Fig. 24.37 G)

(b) Ophthalmoplegia: Due to oedema and cellular infil-tration of the eye muscle and oculomotor nerves, leading to weakness of the superior and lateral rectus and inferior oblique muscles of the eye preventing upward and lateral gaze ( Fig. 24.37 H)

4. Signs of progressive ophthalmopathy: (a) Congestive oculopathy (chemosis, conjunctivitis,

periorbital swelling, corneal ulcerations, optic neuri-tis, optic atrophy)

FIGURE 24.37A Dalrymple’s s ign. FIGURE 24.37B von Graefe sign.

FIGURE 24.37C Exophthalmos relation of eyelids to the iris.


FIGURE 24.37D Exophthalmos.

FIGURE 24.37E Naffziger s ign.

FIGURE 24.37F Joffroy s ign.

FIGURE 24.37G Moebius s ign.

Numerous othe r e ye s igns ha ve be en de scribed:● Hypothyroidism:

● Periorbital puf finess

Neuromuscular System

● Hyperthyroidism: ● Nervousness● Anxiety● Irritability● Tremors ( Fig. 24.38 )● Muscle w eakness● Warm moist hands (sympathetic hyperactivity)● Brisk deep tendon reflexes

FIGURE 24.37H Ophthalmoplegia.

● Hypothyroidism: ● Lethargy● Slowing of intellectual and motor activity● Slow tendon reflex (hung reflex)

Cardiovascular System

● Hyperthyroidism: ● Tachycardia, increased sleeping pulse rate (grade 1—up

to 90 /min, grade 2—90–110/min, grade 3—110/min)● Hypertension● Irregularity of heart rate● Signs of cardiac failure

FIGURE 24.38 Examining for tremors.


● Hypothyroidism:● Bradycardia

Skeletal System

● Examined for metastases and pathological fractures

Oral Cavity

Oral cavity is examined for large tongue (e.g. myxoedema), pale tongue (e.g. anaemia), tongue tremor (thyrotoxicosis), lingual thyroid.

Chest

The chest should be examined for bronchial sounds or absence of breath sounds in lung parenchymal disorders (e.g. metastases), decreased air entry, dullness on percussion and absence of breath sounds (e.g. malignant pleural effusion).

Abdomen

Examination of the abdomen both by inspection and pal-pation has to be done for splenic enlargement (e.g. lym-phoma), hepatosplenomegaly (e.g. Hashimoto thyroiditis, Graves’ disease, liver metastases).

Lymphatic Sys tem The lymphatics and lymph nodes of the entire body should be examined in detail (e.g. lymphoma of thyroid). Examination of the liver and spleen completes the lympho-reticular system, which is useful in diagnosis.

General Ex amination General examination of the patient includes checking for:● Associated anaemia, jaundice etc.● Pretibial myxoe dema● Coarse voice and inspiratory stridor● Change in body weight● Increased respiratory rate in hyperthyroidism

The signs in thyroid disorders are analysed in Table 24.7 . Table 24.8 summarizes some points to remember, which

will help in clinical evaluation of the thyroid swellings.

Note

Look for tongue tremor inside the mouth. Fasciculation of intrinsic muscles may be mistaken for tremors, when the tongue is protruded.

TABLE 24.7 Analysis of Signs in Thyroid Disorders

Lesion Symmetry Laterality Surface Feel Fixity Other features

Nontoxic goitre

Diffuse goitre Symmetrical Bilateral Smooth Soft Nil Mild hypothyroidism

Multinodular goitre Asymmetrical Bilateral Nodular Variable Nil Pressure effects if large

Thyroiditis

Acute and subacute thyroiditis

Either Usually bilateral Irregular Soft Nil Tender, lymph nodes

Chronic

Hashimoto thyroiditis Asymmetrical Bilateral Lobular Woody Rare Late hypothyroidism

Riedel’s thyroiditis Irregular Hard Early Pressure effects, hypothyroid

Diffuse toxic goitre Symmetrical Bilateral Smooth initially Soft, fi rm later Thyrotoxic, bruit

Neoplastic

Adenoma Asymmetrical Unilateral Smooth Firm Nil Nil

Papillary carcinoma Unilateral Irregular Late Lymph nodes

Follicular carcinoma Late Distant metastases

Anaplastic carcinoma Unilateral initially Hard Early Pressure effects, metastases

Medullary carcinoma (nonfamilial)

Unilateral Late Lymph nodes, metastases

Lymphoma Bilateral Early Lymph nodes

Neck

The neck is examined systematically for lymph node enlarge-ments secondary to the thyroid gland tumours. In hypothy-roidism, there is fat deposition on the back of the neck and shoulders.

Auditory System

The ears are examined for hearing loss (e.g. hypothyroid-ism). Pendred syndrome—cretinoid goitre associated with deafness.


TABLE 24.8 Points to Remember While Examining Thyroid Gland

Sign / Symptom Probable cause

Stridor Narrowing of trachea due to carcinoma of the thyroid, retrosternal goitre, scabbard trachea of longstanding multinodular goitre and Riedel thyroiditis

Warmth and tenderness Infl ammation or haemorrhage

Unilateral goitre Adenomas and carcinomas, sometimes Riedel’s thyroiditis

Bilateral goitre Simple goitres, thyroiditis, Graves’ disease

Symmetrically smooth and lobular Neonatal, childhood, early endemic, sporadic goitres, thyroiditis and Graves’ disease

Nodular or irregular Multinodularity is seen in late endemic, sporadic goitres and occasionally in medically treated Graves’ disease, chronic thyroiditis and carcinoma

Non palpable lower border Retrosternal extension

Consistency (not a very reliable sign)

Colloid goitre and goitre of Graves’ disease are usually soft. Benign thyroid nodules when calcifi ed and tense cysts feel hard. In Riedel’s thyroiditis and malignancy, the thyroid gland may be stony hard

Mobility Fixation of the thyroid gland usually indicates the presence of carcinoma though occasionally it may occur in thyroiditis. Overlying skin may be adherent to the goitre due to infl ammation, infi ltration due to cancer, or scarring due to previous surgery

Pulsation, thrill The common carotid artery pulsations are normally felt at the level of the upper border of the thyroid cartilage. A large goitre displaces it posteriorly. It is absent (Berry’s sign) when a malignant thyroid tumour encloses the carotid sheath. Vascular thrill, if felt over the thyroid, is suggestive of hyperthyroidism

Tracheal position Lateral deviation can be due to a large thyroid lobe, a substernal goitre or other intrathoracic abnormalities

Horner syndrome Indicates involvement of the sympathetic nerve trunk on the affected side and consists of: I. enophthalmos (due to paralysis of Muller’s muscle) II. drooping of upper eyelid (pseudoptosis) III. myosis (due to paralysis of dilator pupillae) and absence of spinociliary refl ex IV. absence of sweating on the affected half of the face (anhidrosis) V. fl ushing of the face and nasal congestion due to vasodilatation

Lymph nodes Nodes in the central compartment also move with deglutition. Cervical lymph nodes may be palpable in carcinoma thyroid (especially papillary carcinoma), Hashimoto thyroiditis, acute thyroiditis

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