What is pulsation artifact on MRI?
These artifacts may be seen from arterial pulsations, swallowing, breathing, peristalsis, and physical movement of a patient. When projected over anatomy it can mimic pathology, and needs to be recognized. Motion that is random such as the patient moving produces a smear in the phase direction.
What is CSF pulsation artifact?
Background and purpose: CSF pulsation artifact is a pitfall of fast fluid-attenuated inversion-recovery (FLAIR) brain MR imaging. We studied ventricular CSF pulsation artifact (VCSFA) on axial FLAIR images and its relationship to age and ventricular size.
What is an artifact in the brain?
It is a feature appearing in an image that is not present in the original object. Many different artifacts can occur during MRI, some affecting the diagnostic quality, while others may be confused with pathology. Artifacts can be classified as patient-related, signal processing-dependent and hardware (machine)-related.
How do I reduce the pulsation artifact?
Motion artifacts caused by breathing, cardiac movement, CSF pulsation/blood flow create a ghost artifact which can be reduced by patient immobilization, or cardiac/respiratory gating. Aliasing artifacts can be eliminated by increasing the field of view.
What causes artifacts in MRI?
Artifacts are caused by a variety of factors that may be patient-related such as voluntary and physiologic motion, metallic implants or foreign bodies. Finite sampling, k-space encoding, and Fourier transformation may cause aliasing and Gibbs artifact.
Can MRI detect CSF leak?
Magnetic resonance imaging (MRI) accurately detects CSF leaks and associated complications such as the encephaloceles and meningoceles.
What is CSF signal on MRI?
The CSF in the lumbosacral dural sac can be a useful signal-intensity reference for estimation of the signal of the adjacent structures in patients without severe narrowing of the dural sac or marked scoliosis. It may contribute to assessing spinal disease processes.
What does artifact mean on a CT scan?
At the most basic level, a CT image artifact is any discrepancy between the reconstructed values in a CT image and what is expected based on the material density and the sample geometry.
What causes artifact on MRI?
Physiologic artifacts are caused by patient movement, including breathing, heartbeat, and blood flow. Artifacts can arise from the inherent physics of the MRI, such as the presence of metal or chemical shift. Finally, the hardware and software involved in constructing MRI images can cause artifacts.
How common are MRI artifacts?
MRI artifacts are numerous and give an insight into the physics behind each sequence. Some artifacts affect the quality of the MRI exam while others do not affect the diagnostic quality but may be confused with pathology.