ARDMS (American Registry for Diagnostic Medical Sonography) Practice Test

What does a "cyst" appear to consist of on ultrasound imaging?

1. A solid mass of tissue

2. A fluid-filled sac that appears anechoic

3. A complex mixture of solids and fluids

4. An area of increased echogenicity

The correct answer is: A fluid-filled sac that appears anechoic

A cyst appears as a fluid-filled sac on ultrasound imaging, which manifests as anechoic, meaning it produces no echoes and is dark on the ultrasound image. This characteristic is due to the presence of fluid within the cyst, which does not reflect sound waves in the same way that solid tissue does. The anechoic appearance is a key indicator for distinguishing cysts from solid masses, which typically exhibit echogenicity due to their denser structure. In ultrasound imaging, the distinction between cystic and solid structures is crucial for accurate diagnosis. Fluid-filled cysts can often be benign and may require different management compared to solid lesions, which can suggest malignancy or need for further evaluation. Understanding the anechoic nature of cysts helps sonographers and healthcare providers interpret ultrasound images correctly and determine appropriate next steps in patient care.