LOCAL EXAMINATION
described below: Examination of the thyroid swelling should be made as discussed in Chapter 3 under 'Examination of a swelling, besides these examinations peculiar to the thyroid gland will be described below
A INSPECTION
Normal thyroid gland is not obvious on inspection. It can be seen only when the thyroid gland is swollen. In case of obese and short-necked individual inspection of the thyroid gland becomes more difficult. To render inspection easier one can follow Pizzillo's method (Figs. 27.1A and B) in which the hands are placed behind the head and the patient is asked to push her head backwards against her clasped hands on the occiput. The thyroid swelling may be uniform involving the whole of the thyroid gland (physiological goiter, colloid goiter (Fig. 27.2), Hashimoto's disease. etc.) or isolated nodules of different sizes may be seen in the thyroid region (Figs. 27.3 and 27.4) (nodular goiter). Rarely, a swelling on the lateral side of the neck is not due to enlargement of an aberrant thyroid gland but is caused by metastasis in lymph nodes from hidden carcinoma of the thyroid gland. Ask the patient to swallow and watch
B
for the most important physical sign-a
thyroid swelling moves upwards on
deglutition. This is due to the fact that the
thyroid gland is fixed to the larynx. Other A
swellings which may move on deglutition
Figs. 27.3A and B: Nodular goiter. Note how the swelling moves up during swallowing in the second picture.
are thyroglossal cysts, subhyoid bursitis and prelaryngeal or pretracheal lymph nodes fixed to the larynx or trachea. Such movement of the thyroid becomes greatly limited when it is fixed by inflammation or malignant infiltration. In retrosternal goiter, pressure on the great veins at the thoracic inlet gives rise to dilatation of the subcutaneous veins over the upper anterior part of the thorax. When these are present, ask the patient to swallow and determine, on inspection, the lower border of the swelling as it moves up on deglutition. This is not possible in case of retrosternal goiter. The patient should be asked to raise both the arms over his head until they touch the ears. This position is maintained for a while. Congestion of face and distress become evident in case of retrosternal goiter due to obstruction of the great veins at the thoracic inlet.
A thyroglossal cyst (Fig. 27.5) also moves upwards on deglutition. But the pathognomonic feature is that it moves upwards with protrusion of the tongue since the thyroglossal duct extends downwards from the foramen caecum of the tongue to the isthmus of thyroid gland (Figs. 27.6A and B).
Thyroglossal fistula is seen near the midline a little below the hyoid bone. The opening of the fistula is indrawn and overlaid by a crescentic fold of skin.
PALPATION: The thyroid gland should always be palpated with the patient's neck slightly flexed. The gland may be palpated from behind and from the front. The patient A should be sitted on a stool and the clinician stands behind the patient. The patient is asked to flex the neck slightly. The thumbs of both the hands are placed behind the neck and the other four fingers of each hand are placed on each lobe and the isthmus (Figs. 27.7 and 27.8). Palpation should be carried out in their entirety. Careful assessment of the lower margin. Additional information about one lobe may be obtained by relaxing the sternomastoid muscle of that side by flexing and rotating the face to the same side.
To get more information about a particular nodule of the thyroid gland one may ask the patient to extend the neck. This only makes the nodule more prominent for better the margins of the thyroid gland is important, particularly palpation.
Figs. 27.6A and B: Show that the thyroglos sal cyst moves up with protrusion of the tongue.
Palpation of each lobe is best carried out by Lahey's method (Figs. 27.9 and 27.10). In this case the examiner stands in front of the patient. To palpate the left lobe properly, the thyroid gland is pushed to the left from the right side by the left hand of the examiner. This makes the left lobe more prominen. so that the examiner can palpate it thoroughly with his right hand.
During palpation the patient should be asked to swallow in order to settle the diagnosis of the thyroid swelling. Slight enlargement of the thyroid gland or presence of nodules in its substance can be appreciated by simply placing the thumb on the thyroid gland while the patient swallows. (Crile's method).
During palpation the following points should be noted:
(1) Whether the whole thyroid gland is enlarged? If so, note its surface-whether it is smooth (primary thyrotoxicosis or colloid goiter) or bosselated (multinodular goiter) and its consistency whether uniform or variable. It may be firm in case of primary thyrotoxicosis, Hashimoto's disease, etc., it is slightly softer in colloid goiter and hard in Riedel's thyroiditis or carcinoma in which the consistency may be variable in places.
Fig. 27.7: Shows how to get below the thyroid swelling patient is asked to swallow. The thyroid swelling moves to exclude presence of retrosternal prolongation. The up. Clinician now puts his fingers at the lower margin of the thyroid to be sure that there is no further downward extension of the thyroid tissue.
(ii) When a swelling is localized, note its position, size, shape, extent and its consistency. It must be remembered that a cystic swelling in the thyroid gland often feels firm due to great tension within the cyst which is surrounded by relatively soft surrounding tissue of the gland. A calcified cyst may even feel hard.
(iii) The mobility should be noted in both horizontal and vertical planes. Fixity means malignant tumor or chronic thyroiditis.
(iv) To get below the thyroid gland is an important test to discard the possibility of retrosternal extension. Clinician's index finger is placed on the lower border of the thyroid gland. The patient is asked to swallow, the thyroid gland will move up and the lower border is palpated carefully for any extension downwards (Fig. 27.11).
) Pressure effect from the thyroid swelling should be carefully looked for. Pressure may be on the trachea (Fig. 27.12) or larynx, which may lead to stridor (inspiratory noise of inrushing narrowed trachea) and later on dyspnea. Pressure may be on the
air through esophagus which may lead to dysphagia. Pressure may be on the recurrent laryngeal nerve, which may lead to hoarseness of voice. Pressure may be on even the carotid sheath (Fig. 27.13). If pressure
trachea is suspected, slight push on the lateral lobes will produce stridor (Kocher's test). This test, if positive, indicates an obstructed trachea.
Kocher's test: Gentle compression on lateral lobes may produce stridor. This is due to narrow trachea. This test is particularly positive in multinodular goiters and carcinoma infiltrating into trachea which produce narrowed trachea. The position of the larynx and trachea should also be noted. This may be assessed by placing stethoscope on the suspected zone. Passage of air will indicate the position of the trachea. Simple palpation by an experienced hand will indicate the position of the trachea. Finally, X-ray may be advised to know the exact position of the trachea. Narrowing of the trachea, ie, 'Scabbard trachea becomes quite obvious in skiagram. The carotid sheath may be pushed backward by a benign swelling of the thyroid gland where the pulsation of the carotid artery may be felt (Fig. 27.14). A malignant thyroid may engulf the carotid sheath completely and pulsation of the artery cannot be felt. Sympathetic trunk may also be affected by thyroid swelling. This will lead to Horner's syndrome, i.e., slight sinking of the eyeball into the orbit (enophthalmos), slight drooping of the upper eyelid (pseudoptosis), contraction of the pupil (miosis) and absence of sweating of the affected side of the face (anhidrosis). Obstruction to the major veins in the thorax causes engorgement of neck veins are not uncommon. This sign becomes obvious when the patients are asked to raise the hands above the head and the arms touch the ears. This is known as Pemberton's sign.
(vi) Whether there is any toxic manifestation or not. Primary toxic thyroid is generally not enlarged whereas an enlarged thyroid or nodular thyroid with toxic manifestation is generally a case of secondary thyrotoxicosis. In this case the brunt of attack is generally borne by the cardiovascular system whereas in primary thyrotoxicosis it is the nervous system which is mainly affected.
( vii) Whether there is any evidence of myxedema or not.
(viii) Whether the swelling is a malignant one or a benign one.
Is there any pulsation or thrill in the thyroid?
of thyroid. Occasionally only cervical lymph nodes may be palpable, while the thyroid gland (x) Palpation of cervical lymph nodes: This is extremely important particularly in malignancy remains impalpable. Papillary carcinoma of thyroid is notorious for early lymphatic metastasis when the primary tumor remains quite small. Such enlargement was called 'aberrant thyroid previously, which is nothing but metastatic enlarged lymph nodes. manubrium sterni to exclude the presence
Percussion: This is employed over the of a retrosterna goiter. This is more of theoretical importance rather than practical. Auscultation: In primary toxic goiter a systolic bruit (Figs. 27.15 and 27.16) may be heard over
the goiter due to increased vascularity.
Measurement of the circumference of the neck at the most prominent part of the swelling may be taken at intervals. This will determine whether the swelling is increasing or decreasing in size.
