DISEASES OF THE THYROID GLAND.
BY D. HAYES AGNEW, M.D., LL.D.
The thyroid body occupies a very important position in the neck, being closely related to the larynx, the trachea, the carotid blood-vessels, the pneumogastric, sympathetic, and recurrent laryngeal nerves. These relations render quite intelligible the phenomena which are so frequently present when the gland becomes the subject of disease. It is richly supplied with blood-vessels from the external carotids and the subclavian arteries.
Notwithstanding the obscurity which enshrouds the physiological function of the gland, there are good reasons for supposing that its office in the animal economy is not an unimportant one: indeed, its presence, not in the vertebrata alone, but also in birds, reptiles, and fishes, tends to strengthen this conclusion. The experiments of Zesas appear to show that the thyroid body plays an important rôle in regulating the supply of blood to the brain, and also of supplementing the work of the spleen. The place, therefore, of the gland in the body as an appendage to the vascular system appears to be well chosen.
Congenital absence of the thyroid body is uncommon, though it has been noted by a few writers. Curtin1 met with one case in which the gland was replaced by a mass of fat. Possibly in this instance the fat was the result of a morbid change in the thyroid, and not an evidence of the latter having never been present. Beach2 furnishes another case where on dissection no trace of the gland could be found. Hyrtl speaks of the isthmus being frequently absent—a fact observed by other anatomists.
1 Lancet, 1850, vol. ii. p. 25.
2 Medical Times and Gazette, May 30, 1884, p. 603.
Goitre.
Various names have been employed by different writers to designate enlargements of the thyroid body. Among these may be named bronchocele, tracheocele, thyrophraxia, Derbyshire neck, struma, and goitre. Among English-speaking people the disease is generally spoken of as goitre or Derbyshire neck.
Hypertrophy of the gland may be either general or partial; when general—that is to say, involving the entire body—the term symmetrical or bilateral is employed to designate the enlargement; when confined to a single lobe, it is said to be asymmetrical or unilateral. Not unfrequently limited portions or small areas of one lobe only are affected, causing irregularities or nodosities which may be readily detected by the eye or the touch.
SYMPTOMS.—The earliest evidence of bilateral goitre is the appearance of an unusual fulness and breadth of the lower part of the neck or that part between the sternum and the larynx. This fulness extends laterally under the sterno-cleido-mastoid muscles, partially effacing the suprasternal fossa, and is entirely unattended by pain, heat, redness, or other sign of inflammation. When the disease is unilateral, the swelling is seen to extend from the side of the trachea and larynx outward under the sterno-cleido muscle. The tumor, in consequence of its attachment to the trachea, follows the movements of the latter, and hence will be seen to rise and fall during the act of swallowing or of deglutition.
The progress of the enlargement varies greatly in different cases. After its first appearance it may remain quiescent for years, scarcely causing any change in the appearance of the neck which could be deemed a deformity; in other instances the growth will be progressive, attaining to the size of a goose egg, when it may again remain stationary. It is not common in the United States to meet with those excessive hypertrophies of the thyroid so common in Switzerland, where the gland extends up behind the ears, outward to the margins of the trapezii muscles, and hangs down in front of the sternum a large pendulous mass and imparting a most hideous appearance to the patient.
Pressure Symptoms and the Attendant Phenomena.—It is very remarkable to what a degree hypertrophy of the thyroid may reach without giving rise to any marked functional disturbances. This is due, no doubt, to the character of the enlargement, the cystic and vascular causing less inconvenience than the fibrous or more solid varieties. The pressure symptoms which may ensue are—first, difficulty of respiration. This is likely to follow when the central portion of the gland enlarges in common with the lateral masses, thereby causing pressure directly upon the trachea. This pressure may result in softening, and even complete absorption, of one or more of the rings of the trachea. An irritative cough may appear in the course of the hypertrophy, which is to be referred to the encroachment by the gland on the pneumogastric nerve. Hoarseness and a peculiar croaking voice are also sometimes witnessed, indicating the contact of the tumor with one or both recurrent laryngeal nerves.
Redness of the skin and elevation of temperature on one side of the neck are occasionally present, and sometimes accompanied by dilatation of the pupil of the eye corresponding to the affected side. These symptoms result from pressure upon the sympathetic nerve, and may exist in either unilateral or bilateral goitre. When associated with the latter form of the disease, the sides of the tumor will be found asymmetrical.
GEOGRAPHICAL DISTRIBUTION.—Goitre is met with in all parts of the world. There are, however, localities in which it prevails to a remarkable extent, assuming, indeed, the importance of an epidemic disease. In some portions of Switzerland, as in Savoy and in the Tyrol, there are villages in which scarcely a single inhabitant escapes. The disease is very common in Piedmont and in all deep valleys of the Alps, the Pyrenees, the Apennines, and about the foot-hills of the Cordilleras. In the valley of the Maurienne, Larrey states, nearly all the residents were subjects of goitre. According to the government reports in Piedmont and Savoy, there are 22,371 persons afflicted with bronchocele. There is a notable prevalence of the disease at Schlettstadt on the Rhine. In France the districts where the largest number of cases of goitre is observed are St. Aubin and Rosieux. These places, with others less noteworthy in the same country, it is estimated, furnish not less than 500,000 cases of the disease. In the government of Irkoutsh, which is drained by the sources of the Lena and its tributaries, there were in 1870, according to Hachine, as many as 3400 persons laboring under goitre. Among the inhabitants of Siberia antecedent to the conquest by Russia the disease was scarcely known. Its prevalence after this event was attributed to the habit adopted by the Russians of living in heated and uncleanly rooms, altogether unlike the Siberians, who spend most of their time in the open air. Humboldt speaks of goitre being so common in Honda and Moussa, towns contiguous to the Magdalena River, that very few of their inhabitants escaped the disease.
In England the counties of Derbyshire, Surrey, Nottingham, and Norfolk furnish a large number of cases. In this country New Hampshire, Connecticut, Vermont, and New York are the States which supply the most examples of goitre. In Lower Canada goitre is also quite common.
In Switzerland the disease is frequently associated with mental imbecility (cretinism), though it is not at all established that between the two there exists any necessary connection, as cretinism is often met with in persons free from goitre, and the latter in those whose intellectual powers are unimpaired. Indeed, it has been observed by Burns, that in some countries where goitre is very prevalent cretinism is exceptionally rare; nevertheless, the observations of Lemon and the experiments of Horsley are of a character to leave the relation between the two still an open question.
CAUSES.—The causes of goitre are quite obscure. The disease is in some way associated with countries the topographical features of which consist in high mountains and deep valleys. In illustration of this fact we have only to cite the great prevalence of the disease in Switzerland, in the central mountainous parts of Asia, on the Himalayas and the Andes, as also in the mountains of Brazil. In Europe it may be said that goitre is much more common in the south and south-west countries than in the north and north-west. Sea-coasts are generally exempt from the disease. Bardeleben during the many years in which he acted as chief of the surgical clinic at Greifswald saw only two cases of goitre.
The use of glacier- or snow-water has been charged with the production of this evil, containing as it does large quantities of carbonic acid and other matters not generally found in pure potable water. In opposition to this view we are able to present the testimony of Captain Gerard that in those portions of the Himalayas where the inhabitants for a number of months in each year drink snow-water goitre is really less frequently observed than among those who live at the foot-hills of the same region. This coincides with what Lebert states, that if water from the regions of ice and snow constitutes a cause of goitre, then we should expect to find the disease increasing more and more as the glaciers are approached, when, really, just the reverse is the case, the subjects of such enlargements being seen in greater numbers at the bottom of valleys than in the more elevated regions. The Polar expeditions of Lenstake and Kolleweg, undertaken in the years 1868 and 1870, also contradict the supposed connection between goitre and ice-water, as not a case of the disease was reported, notwithstanding the men drank nothing else; and in Sumatra, where snow is never seen, goitre is quite common. Nor is there any satisfactory evidence that lime- or magnesia-water, also charged with exerting a determining influence in the causation of goitre, has anything to do with its existence. The testimony of Humboldt as to the rareness of the affection at Mariquita, where the water is strongly impregnated with lime salts, and my own observation that throughout the Pequea and Conestoga valleys, both limestone districts, goitre seldom occurs, are inimical to such a theory. From St. Maurice to Martiny in Wallis, Lebert speaks of goitre being very common, notwithstanding the absence of lime formation.
That water, however, does become the medium for certain materials which, taken into the system, produce enlargements of the thyroid, is unquestionably true. In corroboration of this statement we have two notable facts recorded by Frank, who says that at Rheims, where goitre was very common, quite one-half of the tumors disappeared after the source of the old water-supply was abandoned and the town supplied by a branch from the river Verle. And again at Stenseifen, near Schmideberg, where goitre prevailed as an endemic, the disease disappeared on the closing of a fountain which furnished water to the inhabitants of the place.
Atmospheric causes have also been invoked in order to shed light on the production of goitre. Thus it is said that the common occurrence of the latter in very deep valleys, so overshadowed by the dense foliage of timber as to prevent a proper interchange or circulation of air, is favorable to this theory; yet as against this view we have the statement of Humboldt, who says that on the plateaus of Bogota, which are swept by constant currents of air and are quite sterile in vegetation, goitre is common.
That local or geological conditions do exist which are directly concerned in the development of endemic goitre cannot be gainsaid, and these of so active a nature that persons coming from remote districts into such goitrous centres and entirely free from all enlargements of the gland, are liable to suffer in common with the native born. Not only so, but, as has been observed by Virchow, even domestic animals in such localities become subjects of the disease.
The very careful study of this subject by Labour of Newcastle, England, furnishes strong evidence that water passing through calcareous soils alone had little if anything to do with goitre, but when such soils were impregnated with ferruginous and earthy salts the geological conditions were present for developing the disease.
Enlargement of the thyroid body is occasionally seen as one of the late manifestations of syphilis, usually bilateral and attaining in some instances a great size.
Gestation is another and not an uncommon cause of goitre, the tumor appearing in the last months of pregnancy or immediately after parturition. Three cases clearly traceable to the above cause are under the writer's care while penning this article. It is in such cases that the tumors sometimes grow with frightful rapidity. Roberts reports three cases in primiparæ, all of which ran an acute course and terminated fatally by asphyxia.
In Graves' or Basedow's disease goitre forms one of the elements in the morbid circle, and when thus associated may be regarded as a neurosis.
VARIETIES.—Goitre appears under different forms, and not unfrequently one variety is transformed into another. The following classification, resting on a pathological basis, will be adopted, namely—Follicular; Gelatinous; Cystic; Fibrous; Vascular.
In follicular goitre there is a proliferation, both in the cell-elements of the follicles and in the connective tissue constituting their walls. This general hyperplasia of the normal histological components of the gland constitutes a tumor which, for a time at least, remains quite soft and compressible, even communicating to the touch the sensation of fluctuation. The tendency, however, of the growth is not to remain long in this condition, but to become more firm and even hard to the feel.
The fibrous is often a transformation from the follicular goitre, an advanced stage in the life-history of the latter. There occurs a new formation of interstitial connective tissue, which by its accumulation and encroachment upon the follicles lessens, and finally obliterates, them to a degree which converts the gland into a fibroma. It is rare, however, to find this metamorphosis general. Generally the change is limited to portions of the thyroid, and accordingly the tumor in this variety of the disease is found hard, knotty, and incompressible at different points corresponding to the sclerosed portions. The vascularity of the fibrous variety is quite insignificant in those portions of the gland which have been the subject of this morbid change, though in other parts there is a liberal supply of blood-vessels.
Vascular goitre may also be a transformation from the follicular variety, in which, with an increased hyperplasia of the follicular elements of the gland, there is a new formation of blood-vessels taking the place of the connective tissue present in the fibrous form of goitre. When the arterial element predominates, the vessels will be found to be very much dilated and anastamosing freely. These goitres are compressible, have a soft, spongy feel, sometimes pulsate, and on auscultation disclose a distinct bruit, hence the term aneurismal goitre often applied to such. In other instances the venous element predominates, when the swelling will, as in the arterial variety, be compressible and communicate to the ear a well-marked blowing sound or murmur. As the superficial veins, in common with the deep ones, are enlarged and tortuous, the surface of the tumor will often exhibit at different points a bluish appearance. In two instances, and in females of a highly-wrought nervous temperament, I have known the vascular goitre to enlarge in a few minutes to wellnigh twice its usual size, threatening the patient with suffocation for the time, and almost as quickly subside after a free emesis.
In gelatinoid goitre the follicles of the gland are distended so as to form large cavities filled with a gelatinoid- or colloid-looking substance, the product of the enclosed cells. As the distension of the follicles progresses the vascularity of the gland becomes notably less, the vessels being obliterated by the pressure. This tumor may attain a very great size, is much firmer than the vascular goitre, and to the touch has a doughy feel.
Cystic goitre is rarely such in the beginning of its history, being often an advanced stage of the follicular variety. In the transition the compartments of the latter undergo enlargement, their normal cell-contents being replaced by an albuminoid transudation from the vessels of the follicles. This process continuing, the interfollicular connective tissue disappears—a mechanical result caused by pressure. Still later, and from this cause, the walls of the adjoining follicles suffer a similar fate, and as these melt away larger cavities are formed, until at length the whole interior of the gland is converted into a number of loculi, and in some rare instances into one great sac. The gelatinoid or colloid goitre may undergo a similar transformation, and much in the same way. The fluid contents of cystic goitre vary in their physical properties as also in their chemical constitution. Generally the substance contained in the cysts is rich in albumen, has a ropy appearance resembling somewhat the white of an egg, and to the feel is viscous or unctuous, similar to that of the synovial secretion. Sometimes it is dark, resembling coffee-grounds—a condition due to the decomposition of extravasated blood derived from ruptured blood-vessels belonging to the gland. Crystals of cholesterin are also present, formed by fatty degeneration of the cells of the follicles, and mingled with a variable amount of sodium chloride. The cystic goitre is soft and fluctuating, and often grows to a large size.
The blood-vessels of goitre are not exempt from pathological changes, but frequently become the subjects of atheromatous and amyloid changes.
Carcinoma and Sarcoma of the Thyroid Gland.
Malignant growths of the thyroid body are comparatively rare, and when present are accompanied by symptoms sufficiently significant to differentiate them from those which are benign. In both carcinoma and sarcoma the increase of the tumor is rapid; the surface veins become very distinct, and the enlargement is general, affecting the entire gland. In addition to the above phenomena, the evil effect resulting from pressure is sooner realized and more pronounced than in goitre, and in a short time the generalization of the disease becomes apparent in the loss of flesh and strength. Should the tumor be a carcinoma, there will likely follow the infection of those lymph-glands in nearest relation to the neoplasm.
EVIL EFFECTS OF GOITRE.—In this country, though goitre may grow to a large size, it is not common for patients to suffer any inconvenience other than that which results from the unsightly appearance of the tumor; hence life is not seriously imperilled by the disease. Occasionally, however, there are exceptional instances in which unpleasant and even troublesome symptoms are developed. Among these may be mentioned alteration of voice or a slight aphonia in consequence of pressure by the tumor on the recurrent laryngeal nerve. An irritating cough may also exist, and when no evidence of pulmonary trouble is present it must be referred to pressure upon the pneumogastric nerve. Dyspnoea when present results usually from pressure upon the trachea. It has been observed that when this pressure is long continued, particularly in cases of vascular goitre, some of the rings of the trachea gradually disappear, leaving only a membranous tube, which may collapse and cause the sudden death of the patient.
Hiccough and diaphragmatic spasms have also occurred when the enlargement of the gland extended laterally, in consequence of pressure on the phrenic nerve. In addition to the above phenomena there is often experienced in goitre severe neuralgic pains on the side of the neck, in the ear, and over the back of the head, and indeed in the course of any of the branches of the cervical plexus of nerves.
Occasionally I have seen a red blush of the integument on the side of the neck, answering to the largest portion of tumor, accompanied by increased heat, doubtless from the growth encroaching on the sympathetic nerve.
TREATMENT.—The treatment of goitre may be divided into constitutional and local. Too often the management of the disease is conducted in an empirical manner, every variety being subjected to the same routine of remedies. No greater mistake can be made. To attain any satisfactory success it is absolutely necessary that a correct diagnosis of the composition of the tumor shall be known. In follicular and in fibrous goitre much may be anticipated from constitutional and local measures. Those remedies which possess the property of inducing retrograde changes of structure and their subsequent absorption are the ones to be selected for administration, and among these iodine and its combinations rank highest. The compound solution of iodine, the iodide of potash, and the iodide of iron, all have their therapeutical adaptiveness. The earlier treatment is commenced the more hopeful will be the prognosis. If the patient is in all other respects in good health, and especially is somewhat fleshy or given to obesity, the compound solution of iodine should of preference be selected. At first the dose should be small, in order to test the tolerance of the stomach, not exceeding five or six drops three times a day, taken in some sweetened water, orange syrup, or curaçoa, and always about one hour after meals. Every two or three days the dose may be increased one or two drops until eighteen or twenty are taken, beyond which it is not desirable to go. It is in these forms of goitre that the burned sponge (spongia usta) was at one time very generally used as an internal remedy, half a drachm to a drachm being taken twice or thrice daily. As the virtue of the article was due to the iodine it contained, it must necessarily be inferior to the solution of the same substance.
In addition to the constitutional treatment the local use of alterative ointments will be indicated, the best of these being iodoform, iodide of lead, and iodide of mercury. Iodoform will be found most efficient employed in the following formula:
| Rx. | Iodoform, | drachm iss; |
| Benzoated lard, | ounce j. |
This ointment is to be rubbed into the goitre for fifteen or twenty minutes morning and evening, after which a piece of lint smeared with the same should be laid over the tumor, covered with oiled silk, and retained in position by a strip of muslin. If the officinal iodide-of-lead ointment be used, it will be desirable to lessen its strength by the addition of a little simple cerate, as it is liable to cause severe irritation of the skin when thoroughly applied, thus neutralizing in a great measure the value of the application. Whatever unguent is selected, the application will be best made before an open fire.
There are several natural waters which can at the same time with the other treatment be taken with advantage, their efficiency being due to the iodine which they contain. The most valuable of these are Adelheid's Quelle and Wildegger. A glass of either can be drank morning and evening. If after two or three months' continuous treatment under the plan described no impression is made on the disease, or in the event of the iodine acting unpleasantly by causing symptoms of iodism, the iodide of potash should be substituted, administering three times a day from five to twenty grains of the salt dissolved in water and syrup, and well diluted.
Boinet has proposed the mixture of iodine with the food as a very satisfactory mode of introducing the drug into the system; and I suppose that it was on the strength of this suggestion that Michaud, with a view to protect the garrison of Étiennes against the prevailing goitre, ordered iodine to be baked in the soldiers' bread. In cases of goitre associated with a pale, anæmic state of the system it will often be found necessary to alternate, for a time, the remedies already directed with iodide of iron and cod-liver oil.
In follicular and fibrous goitres which prove rebellious to the plan of treatment detailed a resort may be had to injections. From eight to twenty drops of the tincture of iodine should be introduced deep into the substance of the gland by the hypodermic syringe. This procedure can be repeated every three or four days, selecting at each operation a different section of the gland, at the same time carefully watching the effect produced. Any marked elevation of temperature, local or general, accompanied by pain or stiffness of the neck, is the signal for suspending temporarily this form of medication. The favorable signs following injections are the shrinking and increasing hardness of the tumor; and so long as these processes continue progressive no repetition of injections will be necessary.
Electrolysis constitutes another therapeutic resource, applicable not only to the treatment of follicular and fibrous, but also to the vascular, goitre. This agent has been favorably employed by Chvostek of Vienna, and to some extent in this country by Baird and others. The current used by Chvostek was one from a Siemens battery of thirteen elements and strong enough to cause a moderate degree of burning. The time consumed at each sitting is not to exceed five minutes, during which the points of application must be frequently changed.
In vascular goitre, iodine, either internally or locally, effects little good. Ergot is to be preferred. From ten to twenty drops of the fluid extract should be given internally three times a day, with injections of the same amount and used in the same general manner as has been directed for the iodine.
Recently I have been using injections of carbolic acid in vascular goitre, and thus far with the most promising results. Four or five drops of a solution of the crystals of the acid dissolved in glycerin, using no more of the latter than will be barely sufficient to liquefy the crystals, should be deposited by means of the hypodermic syringe deep into different portions of the gland at intervals of four or five days. On the withdrawal of the instrument the puncture can be covered with a strip of rubber adhesive plaster. The acid when thus employed causes the tumor to shrink and become hard.
Gelatinous and cystic goitres are quite intractable to constitutional remedies. They require to be attacked locally. Bonnet has tried caustic potash and chloride of zinc. The applications were made over the front wall of the tumor, and in some instances to the inner surface of the sac. The results were not of a kind to make the method a popular one. Iodine and alcohol have also been thrown into the parenchyma of the gland, and with a like unsatisfactory effect. Setons have had numerous trials. The method is an old one, having been used by Celsus, and revived from time to time by Quadi of Naples, Hutchinson, Kennedy, and Stanton. The object in using the seton is to develop in the tumor a destructive inflammation and suppuration. Any one who has witnessed a case of acute suppuration in the thyroid gland will not be anxious to repeat the experience. The purulent products are profuse, highly offensive, and tax severely the powers of the general system; and to these disadvantages may be added the risks of sloughing, hemorrhage, and septic poisoning.
The treatment which promises most in gelatinous and cystic goitre is either that practised by Gosselin or that by Morrell Mackenzie of London. The plan of Gosselin is to make a very small incision in the skin over the front of the tumor, in order to lessen the resistance to the introduction of a small trocar and canula, through the latter of which, after evacuating the cyst and washing it out with tepid water, he injects the tincture of iodine (fluidrachm j). This injection is allowed to remain about five minutes. Should its discharge be followed by a flow of blood, a second and even a third injection is made before withdrawing the canula. This operation does not materially differ from that practised by V. Dumreicher, except that this practitioner emptied the cyst with an aspirator previous to washing out the sac and injecting the iodine. The method of Mackenzie, however, has succeeded so well in practice that it is to be preferred both for efficiency and safety. In this plan perchloride of iron is substituted for iodine. One part of the iron is mixed with four parts of water, and after partially emptying the cyst with a trocar and canula at its most dependent part the fluid (fluidrachm j–fluidrachm ij) is thrown into the sac by a syringe. The canula is now plugged with a stopper that the injection may be retained. After three days the stopper is removed and the contents of the sac are allowed to flow out. In case the discharge proves to be bloody or serous, the injection is repeated; if, on the contrary, it exhibits signs of pus the iron solution is withheld, but the canula is permitted to remain, that free drainage may be maintained until the goitre has been destroyed by suppuration. During the presence of the instrument the affected part of the neck is covered by a flaxseed-meal poultice.
In gelatinous goitre, when the tumor is multilocular, after tapping and before injecting, I introduce through the canula a plunger, and by pushing it in different directions through the interior of the tumor break up the separating walls of the cysts, and thus open a way for the better diffusion of the injecting material. The plan of Mackenzie, destroying as it does the tumor by a slow chronic form of suppuration, and at the same time draining away the pus as it forms, greatly lessens the risk which might otherwise arise from diffused suppuration, bleeding, or sloughing. At the Copenhagen Congress, Mackenzie stated that he had by the method described treated 193 cases of goitre with only 2 fatal cases, the latter being those of a fibro-cystic form.
In making a comparison between the relative safety of perchloride of iron and of iodine as injections in goitre, the great superiority of the former over the latter is well brought out in the cases collected and analyzed by Schwalbe, 106 in number, for the cure of which iodine was used, death following in 5 cases and diffused suppuration in 22 cases.
When all measures fail to control the growth of a goitre, and the life of the patient is jeopardized from the effects of pressure, the case ceases to be a medical one and must be relegated to the domain of surgery. Fortunately, the necessity for operation rarely occurs. It may be remarked, in closing this article, that the excision of the gland has been followed in several instances by evils greater than those for which the operation was performed. The experiments of Zesas and Horsley on lower animals, and the observations of Kocher after the removal of the thyroid in man, place the question of extirpation of goitre among the unsettled problems of surgery.