Dinghui Wang1 and James G. Pipe1
1Radiology, Mayo Clinic, Rochester, MN, United States
1Radiology, Mayo Clinic, Rochester, MN, United States
Ringing artifacts can occur in spiral imaging at regions with spatially rapidly changing field map, especially with long readout. The proposed deblurring method with a modified model can substantially reduce the ringing artifacts.
Figure 4 Comparison of results. A mask computed based on the Laplacian of Δf0 was used to combine the results of the standard deblurring (a) and the proposed method (c). The combined results are shown in (b). Water and fat in (a) were also low-pass filtered (d). Note that the residual ringing inside the yellow boxes is significantly less in (c) (d) compared to (d).
Figure 5 Results of 2D T2-weighted images with spiral readout length of 45 ms. (a) is the blurred TE image. the field map and and its gradient and laplacian are shown in (b)-(d), respectively. A mask computed based on the Laplacian of Δf0 (d) was used to combine the results of the standard deblurring (e) and the deblurring with low-pass filtered kernels (g). The combined results are shown in (f). The ringing artifacts (pointed by the arrows) in (e) are mitigated in (f) and (g).
