ARDMS Ultrasound Physics & Instrumentation Practice Exam

What units are used to measure pressure in ultrasound?

1. Millimeters of mercury

2. Pascals

3. Atmospheres

4. Newton per square meter

The correct answer is: Pascals

In ultrasound, pressure is most commonly measured in pascals. The pascal is the SI (International System of Units) derived unit of pressure, defined as one newton per square meter. It offers a convenient way to express pressure levels encountered in various physical contexts, including those relevant in the field of ultrasound. Ultrasound equipment and related studies often involve understanding the interactions of sound waves with tissues, which necessitates precise measurements of pressure. The pascal provides a standardized unit that allows for consistency in calculations and comparisons across different studies and applications in medical imaging. While millimeters of mercury, atmospheres, and newton per square meter are also units associated with pressure, they are less commonly used in the context of ultrasound physics. Millimeters of mercury are primarily used in clinical settings such as blood pressure measurements, atmospheres are often employed in contexts involving gas pressure, and newton per square meter is synonymous with pascals but is less frequently referenced in practical ultrasound applications. Therefore, pascals remain the standard and most appropriate unit for measuring pressure in ultrasound.