V. MORBID ANATOMY.
The interest that attaches to the deranged anatomy of the pancreas is the interest of ob scurity—the interest of diagnosis ; I may add, too, the interest of situation ; in fact, it is from the situation of the organ that the importance and obscurity of its pathological relations at once result. Close to the stomach, duodenum, liver, spleen, kidney, aorta, cava, mesenteric glands, and cceliac axis, it finds itself in im mediate relation with the great vascular, nerv ous, :digestive and absorbent centres of the abdomen, and may either affect them second arily, be affected by them, or furnish a source of fallacy and doubt as to vvhether it be it, or they, or both that are implicated : and while it is thus placed at the most important point in the whole range of medical anatomy, its situ ation almost completely precludes it from the advantages of physical diagnosis.
The pancreas enjoys an immunity from disease greater than most organs, but I be lieve this immunity is in part real and in part only apparent ; for it cannot be doubted that one reason why the records of its morbid ana tomy are so scanty, is that in so large a num ber of post-mortems, no examination of the organ is made at all. It is the last to be got at, and the cause of death having been as certained, its examination is looked upon as supererogatory ; besides, it is often obscured and mutilated in the removal of other organs, and its careful dissection from its situation, which is necessary to examine it satisfactorily, is troublesome and not very easy.
Its simplest morbid conditions, and most common, are those of — a. Quantitatively pea-verted nutrition— hy pertrophy and ahophy, induration and soften ing; and the commonest of all is, Hypertrophy. —It is difficult to say pre cisely at what point hypertrophy of the pan creas commences, because the limits within which the size of the gland may normally vary are so extensive that a considerable excess of volume is evidently quite consistent with anatomical and functional health. Generally, the hypertrophy is not pure, but is associated with some induration ; and in the tnajority of cases both the induration and hypertrophy appear to result from chronic inflammation, giving rise to some increase in the proper gland structure, but more to an effusion of lymph between the lobes and lobules by the partial organisation of which a great increase in the amount of the interlobular tissue is pro duced. This gives rise to an appearance of
intersection by opaque membranous septa, giving the gland a scirrhoid character ; and hence, by some this morbid alteration has been considered as the first step towards scirrhous degeneration, and by others as actual scirrhus. Whenever the colour of an enlarged pancreas is deeper and redder than natural it may be inferred that the hypertrophy is due to this chronic inflammatory action. Sometimes the enlargement is slight, sometimes it is very great. Dr. Fearnside% mentions a case in which the gland was four times its natural size, and could be felt as a large tumour during life, although the emaciation was not extreme. The results of the hypertrophy are very various ; sometimes it gives rise to jaundice by pressure upon the gall.ducts ; to dilatation of the stomach, dyspepsia, &c., by pressure on the duodenum and pylorus ; to occlusion, even, of its own ducts t, and to many disturbances, functional and organic, oi neighbouring parts, produced by its altered volume and relations.
Atrophy of the pancreas, mere diminution of volume unaccompanied by any other change, is sometimes idiopathic, but much more fre quently caused by neighbouring disease, as for example, the pressure of some tumour. Morgagni found the pancreas atrophied from the pressure of a tumour in the liver. Dr. Hall found the same condition caused by a scirrhous tumour in the mesentery. M. Guerin observed this lesion produced by a similar cause. 31. Berjaud by aneurism of the aorta ; and M. Mondiere by scirrhous pylorus. In some cases it seems to be pro duced by arrest of its function, as when scirrhous disease of the pylorus has put a stop to the passage of food into the duo,denum. Dr. Wolf mentions a case in which the atrophy seems to have been produced by the ossifica tion of the pancreatic arteries and obstruction of the duct. I do not know if there are any symptoms by w hich idiopathic atrophy de clares itself during life, and in those cases in which it is secondary, the symptoms are those of the primary disease and not those of the pancreatic affection. The degree of wasting is sometimes very great ; Cruveilhier met with a case in which it did not exceed an ounce in weight.