Subspace projection to estimate signal inconsistencies

An apparatus for detecting k-space signal inconsistency and suppressing related image artifacts in magnetic resonance imaging, the apparatus comprising:

• processing circuitry configured to
• obtain magnetic resonance imaging (MRI) data, the MRI data including MR signals as signal data over a period of time, the MRI data being represented as an acquired k-space;
• generate, based on the acquired k-space, a correlation matrix;
• determine a null space of the correlation matrix;
• determine a portion of the acquired k-space included in the null space of the correlation matrix to generate an error k-space, the error k-space representing an artifact present in the MRI data;
• and
• reconstruct an image based on a modified k-space, or by applying a penalty term that is a function of the error k-space,
• wherein the modified k-space is generated by performing one of:
• removing the generated error k-space from the acquired k-space to generate a clean k-space, as the modified k-space, or
• modifying the acquired k-space by
• calculating, based on the generated error k-space, weights for k-space samples used in image reconstruction, or
• omitting, based on the generated error k-space, k-space samples in image reconstruction.