Introduction

Gallbladder disease is well suited for emergency ultrasound investigations. Use of diagnostic ultrasound frequently leads to either confirmation of a presumptive diagnosis or rapid narrowing of the differential diagnoses. However, if biliary ultrasound findings are equivocal or conflict with initial clinical impressions, the emergency physician should be reminded that formal studies or other imaging modalities may be complementary.

In this section, the application of bedside ultrasonography in the evaluation of the gallbladder is discussed.

Focused questions for gallbladder ultrasound

As with all emergency bedside ultrasound, it is important to remember the focused questions you are trying to answer with your ultrasound. In gallbladder ultrasound, these questions are as follows:

1. Are there gallstones?

2. Does the patient have a sonographic Murphy sign?

It is also useful to know the following:

1. Is the common bile duct dilated?

2. Is the anterior wall thickened?

3. Is there pericholecystic fluid?

However, the first two questions are far and away the most helpful and diagnostic (1, 2).

Anatomy

It is important to remember that the gallbladder is not a fixed organ, so it can move to a variety of locations in the right upper quadrant (Figure 7.1). The gallbladder neck does have a fixed relationship to the main lobar fissure and the portal vein. The main lobar fissure connects the right portal vein to the gallbladder neck, and the fissure can be traced between the two (Figure 7.2). Another anatomic relationship that is reliable is that the bile duct is always anterior to the portal vein.