Related Experiment Video
Updated: Dec 26, 2025

Four-Dimensional CT Analysis Using Sequential 3D-3D Registration
Published on: November 23, 2019
Projection-based 3D/2D registration for prospective motion correction
Enrico Avventi1,2, Henric Ryden1,2, Ola Norbeck1,2
1Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden.
A new registration method estimates head motion using collapsed FatNav images. This technique effectively corrects motion artifacts, improving MRI image quality compared to existing retrospective methods.
Area of Science:
- Medical Imaging
- Magnetic Resonance Imaging (MRI)
- Image Registration
Background:
- Motion artifacts significantly degrade MRI quality, necessitating robust correction techniques.
- Prospective motion correction using navigators offers real-time artifact reduction.
- The collapsed FatNav is a navigator designed for short acquisition times and broad sequence compatibility.
Purpose of the Study:
- To develop and evaluate a 3D/2D registration method for estimating rigid body motion from collapsed FatNav images.
- To assess the accuracy and robustness of the proposed registration method.
- To compare prospective motion correction using the developed method with retrospective correction techniques.
Main Methods:
- A projection-based 3D/2D registration algorithm was adapted for collapsed FatNav data.
- Simulations using water/fat separated volumes evaluated accuracy at various resolutions.
- Prospective experiments in a healthy volunteer were conducted, comparing with PROPELLER retrospective correction.
Main Results:
- The proposed registration method demonstrated performance comparable to high-resolution 3D registration in simulations.
- The method showed robustness against different masking strategies and initial motion parameters.
- Prospective correction with collapsed FatNav successfully reduced motion artifacts and improved image quality over retrospective correction.
Conclusions:
- The 3D/2D registration method combined with collapsed FatNav offers an effective balance of speed and accuracy for motion estimation.
- This approach shows promise for prospective motion correction in MRI.
- Further validation across diverse anatomies is recommended.
Related Concept Videos
Relative Motion Analysis using Rotating Axes
However, to express the relative position of point B relative to point A, an additional frame of reference, denoted as x'y', is necessary. This additional frame not only translates but also rotates relative to the fixed frame, making it...
Relative Motion Analysis using Rotating Axes-Problem Solving
Here, in order to determine the magnitude of velocity and acceleration for point...
Curvilinear Motion: Rectangular Components
As the car advances, its position evolves over time. Quantifying the car's velocity involves computing the...
Planar Rigid-Body Motion
Planar motion is typically divided into three distinct categories. The first is rectilinear translation, demonstrated by a subway train that moves along...
Absolute Motion Analysis- General Plane Motion
As the drone's propellers rotate, an upward force is generated that counteracts the force of gravity, enabling the drone to lift off from the ground. This initial movement of the drone is along a straight path, representing a form of translational motion. In this phase, every point on the...

