What is the first step in the three-step process of iterative reconstruction?

The first step in the three-step process of iterative reconstruction is the forward projection of the initial image. In this phase, the initial image data is projected back into the space corresponding to the original raw data acquired during the scanning process. This projection creates simulated data that represents what the raw data would look like if there were no noise or artifacts present.

Forward projection is critical because it lays the groundwork for evaluating how well the reconstructed images match the acquired data. By analyzing this simulated projection in the subsequent steps, professionals can iteratively refine the image through adjustments and corrections to improve its quality and accuracy.

This iterative approach helps reduce noise and enhance spatial resolution, making it a fundamental component of advanced image reconstruction techniques used in computed tomography. Each subsequent step relies on the foundational work done in this initial projection.