PATHOLOGICAL ANATOMY OF TUE LIVER.
If we consult the works of pathological writers upon this subject,we shall observe at every step of our progress the greatest ambiguity and dif ference of opinion to exist. The reasons for this want of consent upon the true nature of the diseases of so important an organ are not to be ascribed either to want of talented ob servers or of excellent observations, but solely to the ignorance which has hitherto prevailed with regard to the exact anatomy of the organ.
I have sliewn that the most celebrated authors found it necessary in starting with their in quiries to establish for their guidance a theory of the structure of the liver ; this theory was based upon imagination or upon deceptive ap pearances ; and upon this frail basis the crumbling superstructure of their pathological deductions is supported. The hypertrophy or atrophy of the white or of the red substance, and the wild speculations of pathological theorists, have now fallen into the shade before the light which recent discoveries have thrown upon the anatomy of the liver. Intimately associated with that anatomy, and with the knowledge of the distribution of the vessels, is the explanation of the mode in which the circulation is performed, and the elucidation of the causes which may give rise to impediment in its course ; in other words, the principles of congestion. Indeed, so closely allied is that condition with the natnral circulation, that Kiernan, in his paper upon the Anatomy and Physiology of the Liver, has deemed it a part of the subject to explain the various conges tions to which the organ is liable, and the manner in which they may be imitated arti ficially. Upon this point we have, therefore, precise information, and the history of con gestion we may regard with a feeling of satis faction. The same observations, with the exact anatomy of the liver as a basis, have not as yet been extended to its diseases; our know ledge of these is therefore necessarily imper fect. Kiernan concludes his paper with a para graph of much importance to this branch of pathology :—" While engaged in the exami nation of the natural structure of the liver, I have not been inattentive to the changes pro duced in it by disease; and, with the permis sion of the Society, I propose submitting to its consideration a paper on the morbid anatomy of this organ." Now this was written in 1838,
and I trust that the time is not far distant when the additional labours of that excellent observer will be placed in the hands of the pro fession.
In the arrangement of the diseases of the liver I have adopted a physiological order, and shall consider its morbid conditions under the seven following heads : 1. Diseases of the serous membrane.
2. Diseases of the mucous membrane.
3. Disorders of the venous circulation.
4. Disorders of biliary excretion.
5. Diseases of the parenchyma.
6. Disorders of function.
7. Lntozoa.
1. Diseases of the serous membrane.—The serous covering of the liver, like serous mem branes in other parts of the body, is liable to acute iqllananation. The effects of this inflam mation are also similar; the capillary vessels become over-distended and lose their power of contraction ; coagulable lymph is effused upon the surface of the organ, and causes its me chanical cohesion to the contiguous serous membrane ; the coagulable lymph becomes organised by the development of new capillary vessels from the meshes of the old, and the adhesions are traversed by vessels of larger size, and constitute a permanent bond of union between the peritoneum proprium and the peritoneum reflexum. In this state, adhe sions are not uncommonly met with upon the convex surface of the liver, but not so fre quently upon its concave side. The inflam matory action is confined to the peritoneum of the organ itself, and that of the parietes of the abdomen immediately in contact with it, and seldom extends to the serous membrane of neighbouring viscera. This is the membranous hepatitis of pathological writers, and is accom panied by considerable local uneasiness, and by sympathetic pains in various parts of the body, dependent upon the communication of its proper nerves with the nerves of other re gions, as with the phrenic nerve, giving rise to pain in the- right shoulder and chest, with cough; with the pneumogastric nerve, producing uneasiness at the cardia,pain along the oesopha gus, dysphagia and nausea ; and with the solar plexus and lesser splanchnic nerve, causing pain in the right kidney, &c. This disease is usually associated with chronic congestion of the substance of the liver, but exists, some times, quite independently of any internal morbid action.