A goitre of small or even moderate size may not give rise to any symptoms, but if large it may press on the windpipe, nerves, blood-vessels, or other neighbouring structures, thus causing shortness of breath, difficulty in swallowing, hoarseness, etc., and sometimes sudden death. The use of drugs or of local applications is of but little service, though sometimes change of locality is beneficial ; and in regions where goitre is common, the drinking water should be filtered and boiled. If the goitre is increasing in size, causes inconvenience, or is disfiguring, surgical treatment should he resorted to. The operation is usually not difficult for a competent surgeon, and involves very little danger.
Exophthalmie goitre (known also as Graves' disease, or Basedow's disease) receives its name from its most conspicuous symptom, the so-called exophthahnos, which means protrusion of the eyes. Persons suffering from this form of goitre have a peculiar staring expression owing to the fact that the eyes are prominent, appear enlarged, and often show a strip of white above and below the pupil, the lids being pushed further apart than normal. " Pop-eyed " is a common term used to describe this symptom. In addition to the goitre and the eye symptoms, there are usually present rapid and irregular heart-action, often giving rise to attacks of palpitation of the heart, throbbing of the blood-vessels in the neck, trembling of the hands and lips, extreme nervousness, irritability, and anemia. The absence of one or more of these symptoms, even of the goitre itself, is perfectly possible, however. Exophthalmic goitre is much more often seen in women than in men, and usually appears during the third decade of life. It is commoner in nervous, excitable people, and in persons in whose families the disease has already occurred ; and it sometimes develops as a consequence of simple goitre. Lack of good food, overwork, emotional strains, exhausting diseases, etc. —that is, all conditions which lessen the physical and mental vigour—are likely to have a share in bringing on the condition. It is usually considered that exophthalmic goitre is the result of over-activity of the thyroid gland, so that the system is overcharged with substances which stimulate the action of the heart and the nervous system. The condition is the exact opposite of the disease next to be described, ,nyxredema, which is due to a lack of the proper amount of thyroid activity ; and the two classes of patients present a profound contrast in appearance. In the former case there is great nervous unrest and excitability, flushed, moist, warm skin, and over action of the heart ; while in the latter case there is stupidity, loss of memory, slow speech, a dry, harsh skin, and lack of facial expression. Exophthalmic goitre is always a serious condition, and requires medical treatment as soon as it is recognised. In mild cases a great deal may be accomplished by rest in bed, with the local application of an ice-bag to calm the heart's action, and by certain drugs. In cases that do not improve under medical treatment, surgical measures are advisable and often effect a cure.
Myxcedema and Cretinism.—When there is deficiency of function of the thyroid gland there results, as has already been indicated, a peculiar change in the physical and mental functions and in the structure of the body, this condition being called nnyxcedema when it occurs in adults, and cretinism when it begins in childhood. Myxcedema is six times more common in women than in men, and is most often seen between the ages of thirty and sixty years. The physical and mental changes are very striking : the sur face of the body becomes swollen, so that the lips and nose are thickened, and all the features grow coarse, the face loses its play of expression, the hands and feet enlarge, the skin becomes rough and dry, the hair falls out, the patient suffers from cold, the voice becomes hoarse and monotonous, speech is slow and halting, and there are mental depression and stupidity, sometimes combined with delusions and hallucinations. The thyroid gland undergoes diminution in size, and finally may waste away completely. In spite of the profound disturbance of the general functions, the disease progresses but slowly, and the patient may live in this pitiable condition for ten or fifteen years. Myxcedema may follow operations for goitre in which no part of the gland is left behind, and sometimes it is a late sequel in cases of exophthalmic goitre.
Cretinism is much more frequent in parts of Central Europe than in Great Britain ; but as the knowledge of the nature of the condition is becoming more widespread, more and more cases are being recognised in this country also. It is not usually noted until the child is about six months old, after which period a remarkable tardiness in development becomes apparent. Growth is slow, the features become coarse, the skin is dry and rough, the teeth are slow to appear, and mental development is greatly retarded. As the child grows older, the abdomen becomes protuberant, the hair is straight and coarse, the fingers become thick and clumsy, the head is disproportionately large, and the expression is vacant and stupid (see Fig. 422). An individual of fifteen or sixteen years may be only three feet in height. Cretins are usually dull mentally, but good-natured, and are likely to become complete idiots. See IMBECILITY.
In few conditions has modern medicine achieved such triumphs as in the treatment of myxcedema and cretinism. Patients with myxcedema, who were formerly considered beyond human aid, can now be restored to their normal condition, and even advanced cretins can be enabled to take care of themselves. This is effected by artificially supplying to the system the thyroid substance which its own gland does not furnish. An extract obtained from the thyroid glands of sheep is used, and under its daily administration the various manifestations of the disease disappear little by little, until finally a complete cure is effected. It is necessary, however, for the patients to continue taking the extract all their lives in order to prevent relapse.