Noise is measured in a water phantom by using the standard deviation of the CT numbers within a region of interest. How often is this test performed?

Of the following ROI measurements, which is the most accurate measurement of a particular tissue?

True or False. The larger the region of interest sampled in a tissue the more accurate the HU displayed.

The image seen in question 25 was obtained using a SFOV of 25cm and a DFOV of 12cm. A year later a radiologist wants to compare a lesion of the parotid gland recently found on a different soft tissue neck scan with this set of images. The radiologist has requested that you reconstruct this year-old set of data to show all of the neck tissues (24 cm). Given the parameters used in the original image and the year later request, can the data set be manipulated to fulfill the radiologist’s request?

Which of the following would be an example of an image rendering technique (uses only image data)?

Which of the following represents the Hounsfield’s established unit for Bone?

Given the WW of 500 and WL of 0 the resulting image would have a short gray scale and high contrast. Which of the following changes would make the resulting image have a longer gray scale?

If electrode B is the anode, what half reaction occurs in this compartment?  In which direction do the electrons flow? What is labeled “e”?

The way a given rock responds to a stress depends on 

Uneven heating of Earth’s surface directly leads to