Figure 4.
Histogram of FBP (white line) vs. Iterative Reconstruction (red line). These figures illustrate the difference in behavior of FBP vs. IR on the same clinical projection data. (A) The area under the histogram curves is the same but the peak is shifted downwards for IR. This is consistent with our expectation that IR will increase image contrast, i.e., the noise is pushed down, and a higher maximum is resolved. (B) In a cumulative distribution curve, the median count of the reconstructed volume is lower which must be considered when making direct comparisons.