N/2 ghosting artifacts: elimination at 3.0-T MR cholangiography with SPACE pulse sequence

Area of Science:

• Radiology
• Medical Imaging

Background:

• Magnetic resonance (MR) cholangiography is crucial for diagnosing biliary and pancreatic duct diseases.
• Ghosting artifacts can degrade image quality and obscure important diagnostic information.
• Optimizing MR cholangiography sequences is essential for improving diagnostic accuracy.

Purpose of the Study:

• To evaluate if a novel sampling perfection with application optimized contrasts using different flip angle evolutions (SPACE) sequence reduces ghosting artifacts in 3.0 T MR cholangiography compared to standard sequences.
• To assess if the SPACE sequence maintains diagnostic image quality and contrast-to-noise ratio (CNR).

Main Methods:

• A HIPAA-compliant study was conducted with institutional review board approval and a waiver of informed consent.
• Fifteen women and fourteen men underwent MR cholangiography using both a standard sequence and the SPACE sequence at 3.0 T.
• Image quality, ghosting artifacts, and CNR were assessed by readers.

Main Results:

• The SPACE sequence significantly reduced acquisition times and completely eliminated N/2 ghosting artifacts.
• Images acquired with the SPACE sequence were perceived as visually grainier and had a lower CNR.
• Despite the drawbacks, readers preferred the overall appearance of images from the SPACE sequence, primarily due to the absence of ghosting.

Conclusions:

• The SPACE sequence offers advantages in reducing scan time and eliminating ghosting artifacts in 3.0 T MR cholangiography.
• Trade-offs exist, including increased image graininess and reduced CNR, which require consideration.
• Further optimization of the SPACE sequence may be warranted to balance artifact reduction with image quality preservation.