Magnetic resonance angiography for the primary diagnosis of pulmonary embolism: A review from the international workshop for pulmonary functional imaging

Figure 4 Artifacts: The Maki artifact. A: Acquisition of the central aspect of k-space was before the bolus of contrast agent filled the pulmonary artery causing a pseudo-clot within the left lower lobe pulmonary artery (arrow); B: Later phase acquisition from the same patient shows normal contrast enhancement of the Left lower lobe pulmonary artery (arrow); C: Gibbs’’ ringing artifact can simulate a central filling defect. Typically, the signal of emboli will be less than 50% of the signal intensity of the lumen.