We now come to the consideration of the diseases of the gall-bladder and its efferent duct, those of the ductus communis choledochus, of the ductus hepaticus, and of the branches and ultimate distribution of the latter. We include the entire apparatus under one head, though we shall devote a special consideration to the peculiar characters exhibited by separate sections.

1. Excess And Defect Of Formation

In rare cases a congenital absence of the gall-bladder has been noticed, an anomaly which must not, however, be confounded with obliteration of the gall-bladder which is frequently consequent upon inflammation. When there are two livers, the gall-bladder and the entire apparatus correspond; but we also find, without any further anomaly, a twofold instead of a single common duct; the two ducts then either both open into the duodenum, or one communiccates with the duodenum, and the other with the stomach.

2. Irregularities Of The Biliary Passages With Reference To Calibre

Independently of congenital enlargement or diminution of these parts, we find important acquired anomalies in the shape of dilatation or contraction.

Dilatation either affects the entire apparatus from the duodenal orifice to the capillary gall-ducts equally or almost equally, or it only affects larger or smaller portions, whilst the remainder retains its ordinary size. The gall-ducts are capable of extreme distension.

We find that dilatation of the passages is caused by habitual accumulation of inspissated bile, and by everything that impedes the progress and the discharge of the secretion. We allude to compression of the biliary passage within and external to the liver by morbid products or enlarged lymphatic glands, to diminution of their calibre by tumefaction of the coats, by cicatrices or unusually large folds or valves of the mucous membrane; to obturation by biliary calculi, by morbid growths projecting into the cavity of the biliary passages, by catarrhal or croupy secretions. Some of these obstacles occur mainly in one, others in another portion of the apparatus. If the impediment occupies the ductus choledochus, the dilatation gradually extends over the entire apparatus; but it must be observed that the dilatation of the gall-bladder does not in general correspond with the dilatation of the other portions, as its efferent duct (ductus cysticus), from opening into the common duct at an acute angle, is compressed by the enlarged ductus choledochus. The more completely the calibre is obstructed, the more complete is the capillary distension; the more rapidly it ensues, so as not unfrequently to induce rupture.

The ductus choledochus is either found compressed by disorganized, and especially by cancerous, lymphatic glands, or by the pancreas, or the passage is narrowed by the tumefied mucous membrane or by the tumefied valve, or it is closed up by a biliary calculus or a carcinomatous tumor from without. Occasionally it is so enormously dilated as to exceed the diameter of the small intestine; the slower this effect is produced, the more marked will be its active character; and the distension extends upwards, passing by the gall-bladder, as above observed, to the hepatic duct and its ramifications.

The channel of the ductus cysticus is found impaired by unusual flexures, or large and numerous mucous folds, consequent upon previous elongation and distension, by cicatrices and cancerous degeneration; it may become perfectly obliterated by the same means, or by biliary calculi, which are impacted in the neck, and more particularly in a lateral dilatation of the gall-bladder. Enormous dilatations of the latter result, which in the course of time induce an entire change in the tissue and the functions of the mucous membrane of the gall-bladder.

After this occlusion has been rendered complete, the residuary bile in the gall-bladder is absorbed; the mucous membrane secretes mucus more copiously, in proportion to the irritation exerted upon it by the stagnating mucus left after the removal of the specific contents of the bladder. The secretion gradually accumulating, the gall-bladder extends, and its mucous membrane becomes converted into a serous membrane, which secretes a serous, albuminous fluid, resembling synovia; this is at first opaque, and subsequently becomes clear, and we detect in it, with the assistance of the microscope, nothing but solitary flocculi of pigmentary matter, and a few crystals of biliary fat. This affection of the gallbladder is termed hydrops cystidis felleae, and the bladder resembles the sound of fishes, being converted into a tense capsule, - a condition similar to that developed under analogous circumstances in the Fallopian tubes, the ureters, the pelves and calices of the kidneys, and even in the vermiform process.

The new lining membrane of the gall-bladder is subject to all the diseases to which serous membranes and their cavities are liable; inflammations occur very frequently, giving rise to the most various exudations, and terminations as various. Among the latter, we allude especially to shrivelling of the gall-bladder, accompanied by diminution of its contents. These become inspissated, so as to form an adipose chalky pulp, or chalky concretion, with a subsequent ossification of the parietes.

The dilatation of the biliary ducts in the interior of the liver is either uniform, and affects the entire organ or certain portions only, or it occurs as a partial saccular dilatation of one or more of those ducts. In the former case the cause is generally to be found in an obturation of the biliary channels within or external to the liver, by means of concretions, cancerous growths, or croupy exudation; and the dilatation very frequently extends from the ductus choledochus to the biliary passages within the liver. In well-marked cases the entire capillary network belonging to this apparatus is dilated and gorged with bile; the parenchyma of the liver may be saturated with bile, and present a dark yellow or green color; the viscus is turgid, though pulpy and friable, resembling the condition of yellow atrophy; the larger ducts contain bile in a disorganized state, and not unfrequently blood in a similar condition.

This affection invariably proves fatal with symptoms of biliary infection of the blood, and consequent cerebral disease, which is often combined with exudation on the arachnoid, with intense icterus and extreme pain in the liver. The capillary ducts are occasionally ruptured, and this gives rise to larger or smaller accumulations of bile in the deep-seated portions of the organ; or the rupture may occur in the peripheral layers, at spots where patches of dilated gall-ducts form rounded, fluctuating projections on the surface of the organ; in this case the hepatic peritoneum frequently becomes involved, and extravasation may take place into the abdominal cavity. Finally, the bile that transudes through the coats of the gall-ducts may, if it reaches the peritoneum, induce peritonitis, which in its turn predisposes to rupture of the serous covering investing the approaching biliary abscess.

The second or saccular form of dilatation of the biliary ducts is generally the result of a catarrhal or blennorrhoic condition. Capsules varying in size from a pin's head to a hen's egg, with a loose mucous lining that forms valvular folds, are found scattered through the liver, and they contain a liquid consisting of blennorrhoic or purulent mucus and bile, which deposits a sediment or incrustations. The character of the investing membranes affords a sufficient distinction from other cavities containing a similar fluid; but the afferent and efferent canal is not easily discoverable, even with the assistance of injections. These dilatations undoubtedly originate in an accumulation of catarrhal secretion, and are generally accompanied by a dull pain in the liver.

Contraction of the biliary passages is induced by the above-mentioned circumstances, and may advance to adhesion and obliteration, as is especially the case in the gall-bladder.

3. Anomalies In The Form And Disposition Of The Biliary Passages

Among these we reckon the various congenital malformations of the gall-bladder, in which it presents an intestinal, cylindrical, extended, twisted, pyriform, or phial-shaped appearance, or in which it seems divided longitudinally or transversely, owing to a rigid condition of the internal folds. To this class also belongs the anomalous insertion of the ductus choledochus into the duodenum or stomach. The acquired malformations consist in contraction, obliteration, or dilatation of the gallbladder; in change of position of the biliary passages, owing to pressure exerted upon them by enlarged lymphatics, morbid growths, etc.

4. Solutions Of Continuity

We regard as peculiarly interesting the spontaneous ruptures occurring in the biliary passages external and internal to the liver as a consequence of excessive dilatation, which is generally preceded or accompanied by inflammatory action. We have also to cite the perforations of the biliary passages external to the liver, resulting from suppuration of their cyats, and the abnormal passages subsequently established between the biliary ducts and the stomach and intestinal canal; as well as certain abscesses produced by suppuration of the capillary gall-ducts within the liver, of which we shall have occasion to speak more fully in the sequel. (See Textural Diseases of the Biliary Passages).