CAMRT Radiography Practice Exam

Disable ads (and more) with a membership for a one time $4.99 payment

Prepare for success with our comprehensive CAMRT Radiography Exam resources. Engage with quizzes, detailed explanations, and hints to boost your confidence. Ace your exam with our dedicated support!

Practice this question and more.

In terms of CT numbers, what is the value typically assigned to blood?

-100
20
0
300

The correct answer is: 20

The typical CT value assigned to blood is indeed around +20 Hounsfield units, which corresponds to option B. Hounsfield units (HU) are used in computed tomography (CT) to express radiodensity, where air is assigned a value of approximately -1000 HU, water is at 0 HU, and various tissues and fluids are assigned values based on their densities relative to water. In this context, blood, being a fluid with some level of density, has a positive CT number. This reflects its composition, which includes water and suspended cells, contributing to its radiographic appearance. The value of +20 HU indicates that blood is denser than water but not as dense as many solid tissues, which have higher positive values. The values assigned to air, water, and dense tissue create a framework that helps in the interpretation and differentiation of various types of tissues in a CT scan. Understanding these values is essential for radiographers when assessing images and diagnosing conditions.