““Mystery creates wonder and wonder is the basis of man’s desire to understand.”

-- Neil Armstrong (1930–2012)

Do you know that, the first MRI image, acquired in 1973 by Paul Lauterbur, was actually a radial MRI image?

Lauterbur's first MRI image - Experimental Setup
Lauterbur's experiment (Source: Nature)
Lauterbur's first MRI image - Reconstructed Image
The first MRI image (Source: Nature)

Although used to create the first ever MRI image, the radial MRI acquisition scheme is not commonly used in clinical practice today. Instead, the Cartesian acquisition scheme is more widely adopted in clinical MRI due to its simplicity, efficiency, and robustness to system imperfections. However, radial MRI has unique advantages such as reduced motion artifacts and applicability in certain applications, which has led to its continued use in research and specialized clinical settings. With the improvement in hardware and reconstruction algorithms, radial MRI has been gaining more attention in recent years for its potential to provide high-quality images with reduced artifacts, especially in applications such as 3D/4D/5D cardiac imaging and liver imaging.

Clinically, radial MRI has been used in liver MRI to reduce motion artifacts and capture the dynamic contrast enhancement of liver lesions. It also has been used in musculoskeletal MRI to generate CT-like contrast via ultrashort echo time (UTE) and zero echo time (ZTE) imaging.

Although not strictly radial, the PROPELLER/BLADE/JET MRI acquisition scheme, which samples k-space in a rotating fashion, has been widely used in brain and body MRI to reduce motion artifacts, where the artifacts are similar to those in radial MRI.

In this post, we will challenge you to identify the causes of the classic artifacts in radial MRI and propose solutions to mitigate them. During the process, we will also re-discover a mysterious artifact and strategy to mitigate it.

The “Halo” Artifact

Halo Artifact in Radial MRI
Halo Artifact in Radial MRI - Question

The “Freaking” Artifact

Streaking Artifact in Radial MRI
Streaking Artifact in Radial MRI - Question

How to Mitigate the “Freaking Streaking” Artifact?

Streaking Artifact in Radial MRI - Question 2

The “Mysterious” Artifact

Reconstructed images from every iteration using the Original Conjugate Gradient SENSE Algorithm (see YouTube if the video does not load)
Mysterious Artifact in Radial MRI

How to Mitigate the “Mysterious” Artifact?

Mysterious Artifact in Radial MRI - Question

Citing this work

If you found this useful, please cite this as:

Hung P. Do, PhD, MSEE (Feb 2026). “AoMP-001-Q: Classic Artifacts in Radial MRI and a Mysterious Artifact (re-discovered).” The Art of MRI physics (AoMP). https://hdocmsu.github.io/blog/2026/02/27/aomp-001-q/

or as a BibTeX entry:

@article{do-20260227-aomp-001-q,
  title   = {AoMP-001-Q: Classic Artifacts in Radial MRI and a Mysterious Artifact (re-discovered)},
  author  = {Do, Hung P. PhD, MSEE},
  journal = {The Art of MRI Physics (AoMP)},
  year    = {2026},
  month   = {Feb},
  url     = {https://hdocmsu.github.io/blog/2026/02/27/aomp-001-q/}
}