TWIST (time-resolved angiography with interleaved stochastic trajectories)

Last revised by Henry Knipe on 19 Oct 2023

Citation, DOI, disclosures and article data

Citation:

Fang R, Knipe H, TWIST (time-resolved angiography with interleaved stochastic trajectories). Reference article, Radiopaedia.org (Accessed on 28 Apr 2024) https://doi.org/10.53347/rID-177537

DOI:

https://doi.org/10.53347/rID-177537

Permalink:

https://radiopaedia.org/articles/177537

rID:

177537

Article created:

19 Oct 2023, Robert Fang

Disclosures:

At the time the article was created Robert Fang had no financial relationships to ineligible companies to disclose.

View Robert Fang's current disclosures

Last revised:

19 Oct 2023, Henry Knipe ◉ ◈

Disclosures:

At the time the article was last revised Henry Knipe had the following disclosures:

Integral Diagnostics, Shareholder (ongoing)
Micro-X Ltd, Shareholder (ongoing)

These were assessed during peer review and were determined to not be relevant to the changes that were made.

View Henry Knipe's current disclosures

Revisions:

2 times, by 2 contributors - see full revision history and disclosures

Sections:

Imaging Technology

Tags:

mri, cases, case2, refs, snippet

Time-resolved angiography with interleaved stochastic trajectories (TWIST) is a 3D time-resolved MR angiography (MRA) sequence - being vendor-specific to Siemens.

In comparison to contrast-enhanced MRA techniques that obtain images at a single point in time, time-resolved MRA obtains a series of images over a period of time, tracking the passage of a contrast bolus.

The principle of TWIST lies with special k-space sampling. The center of k-space holds information about image contrast while the periphery of k-space encodes information on edges and details. The TWIST sequence over-samples central k-space relative to peripheral k-space.

Time-resolved MRA is particularly useful clinically in situations where contrast dynamics are important. Examples include assessment of arteriovenous malformations and investigating collateral flow around vessel stenoses ¹.