zeitliche Auflösung
Temporal resolution relates to the duration of time for acquisition of a single frame of a dynamic process, i.e., cine imaging.
Discussion
The concept of temporal resolution is fundamental to cardiac CT and MRI, in which a rapidly beating heart is imaged over the order of milliseconds into multiple frame-captures. In MRI, the time gap between consecutive images indicates the temporal resolution which is given by the formula:
Temporal resolution = VPS × TR
where
- VPS = views per segment - a user-defined variable and
- TR = time to repetition.
So, for example, if the TR is 10 ms and there are 5 views per segment, the temporal resolution would be 50 ms.
In cardiac CT, a temporal resolution of 250 ms means that a single image is acquired over 250 ms of the cardiac cycle, i.e., 4 images during a single cycle at a heart rate of 60 beats per minute. With modern dual-phase CT scanners, temporal resolutions as low as 42 ms have become possible, enabling better evaluation of regional wall motion.
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