Which processing method is characterized by having a reduced imaging time while utilizing a subset of data?

The Ordered Subset Expectation Maximization (OSEM) method is characterized by reducing imaging time while utilizing a subset of data. This technique enhances the iterative reconstruction process by dividing the total number of projection data into smaller subsets. This allows the reconstruction algorithm to update images more frequently and utilize fewer projections in each iteration, ultimately leading to faster processing times.

In practical terms, the OSEM method promotes efficient use of data and can yield high-quality images in less time compared to traditional full data methods. By using subsets, it leverages speed without significantly compromising the resolution and quality of the images generated.

In contrast, Filtered Back Projection is a more traditional method that does not incorporate subset processing and often results in longer imaging times. Maximum Likelihood Expectation Maximization (MLEM) is similar to OSEM but generally requires full data for each iteration, making it slower. A Transmission Scan refers to a different imaging technique usually unrelated to the iterative reconstruction methods discussed, focusing on mapping the attenuation of radiation, rather than enhancing speed in image reconstruction.