And, lastly, the tumor may open externally through the abdominal walls, or in an intercostal space, under these circumstances, recovery taking place in a majority of cases.

The bursting of the tumor inwardly may be the result of a blow or fall. This has repeatedly proved a cause of sudden death in cases in which the existence of an hydatid tumor had not been suspected. In some cases suppuration takes place within the tumor, converting it into an hepatic abscess.

The clinical history offers nothing which points to this or any affection of the liver until the tumor attains to a sufficient size to occasion inconvenience by pressing on the adjacent parts. So long as the tumor is contained within the gland, it is usually completely latent. It gives rise to no pain nor tenderness, and the hepatic functions are not appreciably disturbed. Tumors of considerable size are not infrequently discovered unexpectedly in autopsical examinations. If, however, a tumor be situated near the periphery, and project considerably beyond the organ, it is apt to give rise to local symptoms directing the attention to the part. Usually, under these circumstances, pain is slight or wanting, but a sense of fulness and uneasiness is felt in the neighborhood of the liver. When pain is present, it is due mainly to inflammation developed by the pressure of the tumor. The pressure upon adjacent parts gives rise to symptoms which differ according to the direction in which the tumor extends. Extending into the thoracic space, it gives rise to dyspnoea on exertion, cough, and palpitation. Pressure on the stomach and intestines is liable to produce vomiting and constipation. If the vena cava be compressed, cedema of the lower extremities follows. The growth of the tumor is slow and attended with little or no constitutional disturbance. There is no febrile movement, and the nutrition of the body may be unimpaired.

As

Important local and general symptoms, however, are incident to the bursting of the tumor, or the discharge of its contents by ulceration. These symptoms will depend on the direction in which the opening occurs. already stated, pleuritis, pericarditis, and peritonitis, are results of the opening, respectively, into the pleural, pericardial, and peritoneal cavities, and the two latter affections, thus induced, are uniformly fatal. The first of these three affections is very apt to prove fatal. Opening into the vena cava, it gives rise to the symptoms of obstruction of the pulmonary circulation from thrombosis. If the lung be perforated without general pleuritis, pneumonitis is apt to follow; cough and expectoration are prominent symptoms, and in the latter are contained, from time to time, hydatids, together with bile in some cases. If perforation of the lung ensue after the evacuation into the pleural sac, the phenomena of pneumo-hydrothorax are developed. Perforation of the stomach or colon is usually attended with severe pain, and is followed by the discharge, either by vomiting or stool, of hydatids. The discharge of the hydatids into the biliary passages gives rise to jaundice. Jaundice, irrespective of this cause, is rare in cases of hydatid tumor. Dropsy of the peritoneum does not belong to the clinical history of the affection. Both jaundice and hydro-peritoneum, however, are occasionally effects of the pressure of the tumor on the biliary passages without the liver, and on the vena portæ.

A diagnosis is impracticable so long as the growth does not extend beyond the gland. The affection can only be recognized when either the tumor is discoverable by physical examination, or hydatids are discharged through some outlet. A tumor extending from the anterior surface, or from the inner or lower margin of the liver, after it has attained to a certain size, is apparent to the touch. The diagnosis now involves its discrimination from other tumors. When situated over the liver, it is to be discriminated from

cancer and hepatic abscess. This discrimination may generally be made without much difficulty. From cancer it is distinguished by its smooth and globular form, its elasticity and the sense of fluctuation, freedom from pain, and absence of the cancerous cachexia. From hepatic abscess it is distinguished by the slowness of its growth, absence of pain and tenderness, and by its being unattended by the constitutional symptoms to which suppuration generally gives rise, viz., chills, febrile movement, etc. Extending from the inner border, it is to be discriminated from cancer of the stomach or pancreas, and from an aneurismal tumor. The connection of the hydatid tumor with the liver, and the disconnection of other tumors, may generally be ascertained by palpation and percussion. Cancer of the stomach or pancreas is usually accompanied by pain, and, in the former situation, by notable gastric symp toms, and the cancerous cachexia may be apparent. The cancerous tumor is generally irregular or lobulated. An aneurismal tumor is distinguished by its anterior and lateral pulsation, the frequent occurrence of murmur, and generally by persisting gnawing pain referable to the back.

A physical sign, sometimes obtained by percussion, is highly distinctive of a hydatid tumor. If percussion be made upon the tumor, the fingers of the left hand or the whole hand being placed over the tumor, the collision of the floating hydatids with each other causes a characteristic tactile vibration known as the hydatid fremitus. The sensation is compared to that felt when percussion is made upon the hand resting on a mass of jelly. M. Briancon has shown, by filling an ordinary bladder with liquid, and introducing a greater or less number of hydatids, that this sign is due to the latter, and that, other things being equal, the fremitus is marked in proportion to the number of hydatids introduced. By placing the stethoscope over the tumor, and practising percussion, a peculiar sound is elicited, which, in some cases, has a musical intonation like the sound from a violoncello. These signs are obtained in only a certain number of cases, the proportion being about one-half, according to Frerichs.

An hydatid tumor, encroaching more or less upon the thoracic space, gives rise to flatness on percussion, and absence of respiratory murmur from the base of the chest upward in proportion to the height to which the tumor extends, with, perhaps, more or less displacement of the heart. The signs are those of pleuritis with effusion. Attention to the following point will suffice for the discrimination in many if not most cases. In pleuritis, the level of the liquid effusion, when the patient is sitting or standing, is denoted by flatness extending upward on each aspect of the affected side of the chest, to about the same distance; in other words, the upper limit of the flatness is indicated by a line passing horizontally, or nearly so, around the affected side. But the flatness due to a tumor extending into the thoracic space generally has an irregular limit-that is, the flatness extends higher at some than at other points. Moreover, the test of the presence of liquid effusion, afforded by the results of percussion when the position of the body is changed from the vertical to the recumbent, is not available in the case of a tumor.

The diagnosis in cases in which the tumor opens externally, or its contents are discharged by expectoration, vomiting, or stool, is established by the discovery of hydatids either entire, or the remains left after their destruction. If entire, they are easily recognized with the naked eye. If not entire, the microscope is to be employed to discover shreds of the characteristic membrane, and hooklets of echinococci.

There is still another means of arriving at a positive diagnosis, viz., by introducing into the tumor an exploring canula, and withdrawing a little of

Vide Davaine, op. cit.

the liquid. If a clear liquid, like water, escapes, which does not coagulate by the addition of an acid, and, on evaporation, leaves crystals of the chloride of sodium, there can scarcely be room for doubt as to the character of the tumor. If the hydatids are destroyed, the liquid may be turbid. In this case, microscopical examination may show hooklets of echinococci. An exploring puncture, made with a very small instrument, is attended with little or no danger.

A tumor caused by distension of the gall-bladder offers, in its general physical characters, a close resemblance to an hydatid tumor. But as a large accumulation of bile in the gall-bladder involves obstruction of the common duct, jaundice necessarily exists, and in an intense degree. This goes far in the differential diagnosis. Other points are, the form of the tumor resembling that of the gall-bladder, viz., egg-shaped, and its situation at the inferior border of the liver.

Age is of some account in the diagnosis. Hydatids occur mostly in middle life, rarely in childhood or old age. They occur most frequently among the lower classes of society. It may be stated, in this connection, that they occur more frequently in some countries than in others. They are certainly extremely rare in this country.

Hydatid tumors are not in themselves serious except from their size. They do harm by pressure upon adjacent parts. They prove serious, also, by opening into situations in which grave or fatal diseases are induced. The prognosis in these cases has been already stated. If the opening occur in a situation whence the contents are discharged from the body, viz., through the integument, into the bronchi, or the alimentary canal, recovery may be hoped for, or expected, according to the circumstances in individual cases. If recovery do not take place, the fatal termination is preceded by protracted irritation and progressive exhaustion due, generally, to suppuration within the sac.

The growth of the tumors is generally extremely slow, and, hence, the duration of the affection is long. After the existence of a tumor is ascertained, many months, and in some cases, many years, elapse before it attains to a size sufficient to cause serious results or great inconvenience. Of 24 cases analyzed by Barrier (cited by Frerichs), in 3 the affection lasted for 2 years; in 8, for periods between 2 and 4 years; in 4, from 4 to 6 years, and single cases exemplified its duration for 15, 18, 20, and 30 years.

In the treatment of hydatid tumors of the liver, there are two objects to which measures may be directed. One object is the evacuation of the tumor; the other object is to arrest its growth and promote absorption of its contents. Medicinal means are applicable to the last-named object only; the first object is, of course, to be effected exclusively by surgical interference.

Several internal remedies have been proposed as capable of destroying the hydatids. When this takes place, the tumor ceases to grow, and, gradually diminishing in size, may finally disappear. This is the mode in which a spontaneous cure not infrequently takes place. Calomel, common salt, and the iodide of potassium, have been thought to have the power of effecting the destruction of the hydatids, these remedies acting by being absorbed and exerting a poisonous effect upon the entozoa. Their efficacy, however, does not appear to have been established by clinical observation. There is no well-authenticated case in which either of these remedies, or any other, has proved successful. With our present knowledge, a cure is not to be effected in this way, and the curative treatment, therefore, relates exclusively to surgical measures.

The most effective surgical measure, in certain cases, is to make an incision into the tumor, sufficiently large to remove both the liquid and the

hydatids which it may contain. This operation is warrantable, if not advisable, whenever the tumor extends in an outward direction, provided adhesions have taken place around a space in which the opening is made, so that there is no danger of the escape of the contents into the peritoneal sac. A method of determining whether adhesions exist or not, is to ascertain whether the tumor, or the liver, be depressed by a forced inspiration, or remain fixed in the same position. This point is readily ascertained by marking on the chest or abdomen the situation of the tumor, or the lower margin of the liver, or its upper margin, successively at the end of an expiratory and an inspiratory act. After evacuating the tumor, cicatrization may be expected to follow, but this result may be preceded by suppuration within the sac, which may be continued so as to involve danger from constitu tional irritation and exhaustion. If there be doubt as to the existence of adhesions, an incision may be made down to the tumor, and the wound kept open with lint for several days before opening the tumor, as in cases of hepatic abscess. Opening the tumor by means of caustic applications, after the method of Récamier, is more tedious and painful, without affording more security than the former method.

Another method of surgical treatment is to withdraw more or less of the liquid by means of a small exploring canula, employing a certain amount of suction force if necessary. A portion of the liquid may be withdrawn at one.operation, and the operation repeated from time to time. The effect of this procedure is to diminish the size of the tumor, and to destroy the hydatids, a cure taking place somewhat as it does spontaneously when the liquid is absorbed after the destruction of the hydatids. And if the hydatids. be not destroyed by withdrawing the liquid, a medicated liquid may be injected into the sac with a view of effecting their destruction. Iodine, alcohol, and bile have been employed for this purpose. These measures have been successfully employed in several cases.1

Evacuation by means of a small canula in cases in which the tumor extends within the thoracic space, or projects from the margin of the liver into the abdomen, may involve a certain amount of danger from the escape of the liquid into the pleural or peritoneal cavity. A precaution to be observed with reference to this accident, is enforced by Boinet, viz., to make firm pressure over the tumor for some time after the canula is withdrawn; afterward a firm bandage with a compress should be applied. As a set-off against some risk from the operation, the liability of rupture taking place and the discharge of the contents of the tumor into these cavities, is to be borne in mind.

Jobert recommends leaving the canula in the sac for twenty-four hours in order to excite a certain amount of inflammation, and to prevent an escape of the liquid into the serous cavity.'

An Iceland physician, Dr. Thorarensen, has reported a case in which repeated shocks of electricity, conveyed within the tumor by means of steel needles, destroyed the entozoa and effected a cure. This method of treatment merits further trial.

Aside from surgical interference, the treatment of hydatid tumors of the liver embraces only such palliative measures as may be indicated by the circumstances pertaining to individual cases. The treatment of pleuritis, pneumonitis, and peritonitis induced by the discharge of the contents of the tumor, does not claim distinct consideration.

Vide Davaine, op. cit.

I have been led to consider briefly the surgical treatment of hydatids of the liver, from the fact that I do not find it considered in several comprehensive works on surgery which I have consulted.

PIGMENTARY DEPOSIT WITHIN THE LIVER.

A deposit of dark-colored granules in the liver, giving to the organ a steel-gray, chocolate, or bronzed appearance, is observed not infrequently after death from the so-called malarious fevers. A similar deposit generally coexists in the spleen, and may be found in other organs. It is found in the blood, especially within the portal vessels. The source of the pigmentary matter, together with its pathological relations and effects, cannot be considered as settled. With our present knowledge, the pigment liver is hardly entitled to be reckoned in the list of hepatic affections. It will be referred to hereafter as entering into the anatomical characters of the periodical fevers.

HYPERTROPHY OF THE LIVER.

Hypertrophy of the liver was supposed to be not infrequent, before the several degenerative affections to which this organ is liable were as well understood as now. The volume of the liver is often increased, but it may be doubted whether this ever proceeds from hypertrophy. The existence of true hypertrophy, as a morbid lesion of the liver, is questionable. At all events, the physician is never called upon to recognize and treat hypertrophy of this organ. The meaning of true hypertrophy is, of course, to be borne in mind, viz., abnormal growth of a part, with no abnormal change in composition or structure.

CHAPTER XIII.

DISEASES AFFECTING THE SOLID OR COLLATITIOUS VISCERA OF THE ABDOMEN.-CONCLUDED.

Diseases Affecting the Biliary Passages-Jaundice or Icterus-Functional Affections of the Liver-Affections of the Spleen-Affections of the Pancreas..

DISEASES AFFECTING THE BILIARY PASSAGES.

THE diseases affecting the liver which have been considered relate, for the most part, to the parenchyma or substance of the organ. The biliary passages within and without the liver, inclusive of the gall-bladder, are liable to disease. Inflammation of the mucous membrane lining the excretory ducts is probably an affection of not infrequent occurrence. Ordinary inflammation, that is, analogous to inflammation of other mucous membranes, constitutes, as there is reason to believe, the pathological condition giving rise to the affection called icterus or jaundice, in the majority of the cases in which this affection is not incident to structural lesions of the liver or surrounding parts. The opportunity of obtaining autopsical proof of this is rarely offered, because ordinary inflammation in this situation does not prove fatal. The swelling of the membrane and the accumulation of mucus within the ducts occasion more or less obstruction to the passage of the bile; hence its reabsorption, constituting jaundice. The clinical history of cases of jaundice referable to this pathological condition generally shows the inflammation to have had its