Acquisition time
Last revised by Mateusz Wilczek
on 20 Mar 2025
Citation, DOI, disclosures and article data
Citation:
Ballinger J, Wilczek M, Knipe H, et al. Acquisition time. Reference article, Radiopaedia.org (Accessed on 26 Mar 2025) https://doi.org/10.53347/rID-22553
rID:
22553
Article created:
7 Apr 2013,
J. Ray Ballinger
Disclosures:
At the time the article was created J. Ray Ballinger had no recorded disclosures.
View J. Ray Ballinger's current disclosures
Last revised:
20 Mar 2025,
Mateusz Wilczek
Disclosures:
At the time the article was last revised Mateusz Wilczek had no financial relationships to ineligible companies to disclose.
View Mateusz Wilczek's current disclosures
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Synonyms:
- Time of acquisition for a conventional spin echo or gradient echo sequence
- Time of acquisition
- Acquisition times
The time of acquisition for a conventional spin echo or gradient echo sequence is the product of the repetition time, phase encoding steps, and number of averages (TR x phase steps x NEX).
For example, with a one-second TR, 128 phase steps, and two averages, we would get an acquisition time of about 1 x 128 x 2 = 256 seconds, or 4 minutes and 16 seconds. The actual time will be slightly longer.
Fast spin echo and fast gradient echo sequences (e.g. echo planar imaging) perform more than one phase encoding step per repetition time, reducing acquisition time by the number of phase steps per repetition time.
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