What is a common gallbladder pathology

The sonography of the gallbladder

If we systematically scan the liver in longitudinal sections of the upper abdomen, we will come across the gallbladder, which is shown in the ultrasound image exactly as it is in the anatomical sketch (center). We recognize the ventral liver capsule, the lower edge of the liver and the gallbladder, the longitudinal axis of which runs obliquely from dorsocranial to ventrocaudal, so that the fundus of the gallbladder reaches up to the abdominal wall. The fundus extends right up to the colon (C. transversum or right flexure). The duodenum is located dorsal to the gallbladder.

Here again the typical topography of the gallbladder in the longitudinal section of the upper abdomen. The upper limit for the size of the gallbladder is a length of 10 cm and a volume of 100 ml. The wall of the filled gallbladder when fasting is an even, narrow white line. Formally, the wall of the gallbladder should not be thicker than 2 mm. In the area of ​​the transition to the infundibulum, the plica spiralis (Heister's valve) can be seen in the sketch. This can be seen as an echogenic protrusion into the lumen. In addition to the anatomical structures, the top right picture shows a dome-shaped reflex in the gallbladder with an acoustic shadow, the typical finding of a gallbladder stone.

The gallbladder can also be visualized in the longitudinal axis of the organ via the intercostal incision. Both modes of representation have the advantage that the infundibulum can be seen clearly. In the intercostal section we also see the right branch of the portal vein running towards the transducer and the vena cava below. The fundus of the gallbladder is superimposed by intestinal gas in the picture above, which is probably due to the right colonic flexure.

The third level of gallbladder imaging is the subcostal incision. As with the liver screening, the transducer is "placed" flat on the skin and then slowly straightened with slight compression. First liver veins appear, then the portal venous system as "portal vein antlers" (center picture). From the right portal branch a small hyperechoic band leads us to the gall bladder (picture on the right). This is completely scanned by further erecting and moving the transducer.

Deflated and hydropic gallbladder

In the very small postprandially emptied gallbladder one always sees an even layer of walls. The hydropic gallbladder on the right shows a completely inconspicuous delicate wall. It was an obstructive jaundice with a distal biliary obstruction.

Different pictures of microliths. The left picture shows numerous tiny concrements that together form a compact layer, creating a clear and broad acoustic shadow. In the picture on the right you can see a single tiny stone, which forms a sound shadow despite its small size.

In the picture on the left, the dorsal gallbladder wall appears slightly irregular, the patient has a history of acute pancreatitis. After repositioning on the left side and continuing the examination, one can see how the stones detach from the ground and slide along the force of gravity over the gallbladder mucosa.

In the left picture you can see the infundibulum, shown via an intercostal incision. You can see a clear tip reflex and a sonic shadow. The calculus appears to completely close the infundibulum. In the right picture you have to take a closer look. At first glance, the spherical shape of the gallbladder is striking. This picture is caused by the fact that the fundus is kinked in relation to the infundibulum. The stone is no longer surrounded by bile fluid, which makes it difficult to recognize. Buttop reflex and sonic shadow are clear.

When the gallbladder is completely filled with a large calculus and there is no more bile surrounding the stone, diagnosis is difficult. It helps if the suspicious stone finding can be located in the typical location of the gallbladder. The acoustic shadow behind stones usually shows fewer "gray" artifact echoes, it appears "darker" than behind Kolongas.

Thickened bile can appear as the echogenic content of the gallbladder with a finely granular structure. Sludge can be so viscous that it appears as an irregularly shaped conglomerate, as in the picture on the right

Sludge is often an indication of a bile drainage disorder. It is therefore not surprising that it occurs together with concrements. In the left picture the stone dome and acoustic shadow are only faintly recognizable, in the right picture very clearly. Here the concrement is trapped in the infundibulum and the entire gallbladder is filled with sludge. The patient had typical biliary colic.

Gallbladder polyps are adherent to the wall, cannot be repositioned and do not show any acoustic shadow. So-called cholesterol polyps can be very hyperechoic. Gallbladder polyps less than 1 cm in size do not require therapy.

In acute cholecystitis, the tenderness of the gallbladder shows an irregular stratification on ultrasound, which is caused by wall edema and exudation into the liver bed. In contrast to this, the chronically inflamed gallbladder wall is usually only thickened with an echo, without the hypoechoic lamellae visible in the picture.

The gallbladder can have different norm variants such as septa, diverticulum, kinks. Cholesteatosis consists of cholesterol deposits on the wall which, as shown above, produce a small comet's tail artifact on ultrasound.

The picture shows the sonographic findings of a gallbladder carcinoma. The structure of the gallbladder is completely eliminated, one sees an irregular mass in place of the gallbladder. The picture comes from the Albertinen Hospital in Hamburg.

You can find more pictures of gallbladder pathology in the excellent sonography atlas that our colleagues there have compiled.