Artifacts

Sources and Impacts

MRI artifacts are generated by multiple sources including:

  • MR scan gradients
  • Magneto hydrodynamic (MHD) effect
  • Heart motion
  • Blood-flow
  • Other body & organ motion

Artifacts impair image quality causing blurring of the imaged object resulting in misleading pathologies and need for rescans.


They also obstruct diagnostic-quality ECG monitoring for heart-rate variability, arrhythmia, PVC, ischemia, etc.) during MRI exams, resulting in risks to patient safety.


MHD effect (see image below), is considered a prime artifact because of its corrupting affect on ECG ST segments




Magnetic Field Strength and ARTIFACTS

Electrical voltages are generated bytThe MRI's gradient switching, magneto-hydrodynamic effect (MHE) and multiple types of  body motion. These voltages interfere with ECG morphology obstructing image synchronization, diagnostic-quality ECG monitoring and robust decision-support data availability.


As soon as a patient is placed in the MR bore, and prior to scanning, they are under MHE influence  which causes an amplitude increase in the T-wave of the EKG, which is frequently confused with the  standard "trigger point".  This, plus artifacts caused by current multiple filtering methods, impairs image quality, safety monitoring and acquisition of physiological data (ECG, blood-flow) that can be extremely helpful to determine patient health assessments and treatment decisions.


As magnet strengths increase, so do their related  artifact impacts, in particular MHE.


Magnet Strength:  The ECG image (right) shows an ECG taken outside the magnet ("0 T"). 


At 1.5 T, the MHD impact shows an alteration of the T-wave and distortion of the T-Q wave, which becomes much stronger at 3.0 T.  

image1

ACDx Technology Benefits

Artifact Reduction

By cleanly separating signals obtained during MRI procedures, ACDx can:

improve gating and triggering accuracy to produce reliably clearer images, even during cardiac events.

Reduced exam times

Clearer images mean fewer rescans,  shorter exam times and increased MRI throughput.

Diagnostic-quality ECG monitoring

Full, real-time diagnostic-quality ECG monitoring means, during procedures, you can reliably monitor your patient's heart-rate & heart-rate variability, PVCs, arrhythmic and ischemic occurrences with early-warning of any ECG complications.

Blood-flow monitoring

With ACDx, you will be able to monitor your patient's blood-flow while scanning. 

Enhanced Decision-Support

Synchronized image and physiologic data reports will be available on a pay-per-click basis, providing greater evaluation intelligence.

Key to new benefits

We anticipate new clinical and research applications to emerge from ACDx capabilities, enabling users to go beyond current Gating & Monitoring limitations.