The margin of the liver exhibits a depression lodging the gall bladder nearly opposite the centre of its vertical depth.
As the liver is so deeply situated, percussion is found to be the method of examination which gives the best results. Beyond the limits of the zone of auscultation, percussion gives above a semi-dull sound, then, proceeding downwards, a dull sound due to the liver, the omasum, and the collection of liquid in the bowel. When this dulness is well defined, clear, broad from above downwards, and extends to or beyond the hypochondrium, it indicates hypertrophy of the liver. By deep palpation of the posterior margin of the hypochondrium the liver can then be sounded, and its excessive size detected.
The symptomatology of the liver is still very imperfectly understood, for in practice the urine is rarely tested for bile pigments, nor attempts made to ascertain whether the glycogenic function is normal by the test for alimentary glycosuria.
In this connection nothing has yet been done to assist in diagnosing certain hepatic conditions. Fortunately, those diseases of the liver which we have to study are more often of a parasitic nature than true diseases of the hepatic tissue.
The reported cases of venous or biliary cirrhosis, moreover, are too ill-defined and too incomplete to be taken as a type for description. We leave them on one side. In a similar way, apart from parasitic cholangeitis and cholecystitis, inflammations of the biliary ducts are little known, and are rare.
CONGESTION OF THE LIVER.
In bovine pathology only passive congestion of the liver, often a result of various primary affections with cardiac lesions, is well recognised.
Active congestions probably occur during infections or intoxications of various kinds, but have not been made the object of special research.
Among diseases likely to produce passive congestion must be included all those which interfere with the return circulation through the posterior vena cava. All cardiac affections with lesions of the valves or orifices of the right heart, all forms of pericarditis, tumours or lesions of the mediastinum compressing the posterior vena cava, produce stasis, passive congestion, and progressive development of what is called “cardiac liver.”
Symptoms. The liver is considerably hypertrophied, as a consequence of the stasis of blood and progressive dilatation of the portal system. Its zone of dulness increases in size, whilst on palpation its borders may sometimes be detected. This condition is always accompanied by digestive disturbance.