In ____, a Pre-Contrast Image Referred to as a Mask

question 21

Multiple Choice

In ____, a pre-contrast image referred to as a mask image is first obtained and post-contrast images are then digitally subtracted from the mask image.

• A) digital subtraction angiography
• B) temporal subtraction
• C) temporal frame averaging
• D) last-image hold

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Definitions:

Interval Data

Data with meaningful distances between measurements but no true zero point, allowing for operations such as addition and subtraction.

Ordinal Data

A type of categorical statistic that involves data classified into categories within a defined order but not necessarily with equal intervals between categories.

Nominal Data

Data that is categorized into distinct groups without any order or ranking between them, used for labeling or naming categories.

Ordinal Data

Data that can be categorized or ranked in order, but the intervals between ranks may not be equal.