BLADE/ PROPELLER Artifacts

The BLADE/ PROPELLER acquisition pattern, which involves acquiring data in a rotating blade-like pattern, can introduce aliasing artifacts under certain circumstances. The most common cause of aliasing artifacts in BLADE/ PROPELLER imaging is insufficient coverage of k-space, which can occur due to factors such as:

Inadequate FOV: If the field of view (FOV) is not properly planned or set too small, it may not fully encompass the anatomy of interest. This can lead to aliasing artifacts as the information beyond the FOV is folded back into the image.

Motion-induced aliasing: If there is significant motion during the acquisition, such as patient movement or pulsatile flow, the motion-related signal can cause aliasing artifacts due to undersampling or mismatches between consecutive blades.

Incomplete blade coverage: If the blades do not fully cover the desired field of view (FOV), areas outside the blade coverage may exhibit artifacts or reduced image quality.

Absence of phase oversampling: The absence of phase oversampling means that not enough data points are acquired in the phase-encoding direction. As a result, high-frequency information in the image may exceed the Nyquist limit and fold back into the image as low-frequency information, leading to streak-like patterns or distortion.