Retrospective reconstruction of the data set allows for adding thin slices into thicker and thereby reducing image noise. An overlapping reconstruction increment of a narrow collimated scan also allows for multiplanar reformatting with good spatial resolution. The thin slices of the MPR stacks are added into thicker slices to reduce noise.
A 40 second scan (4 X 1.0 mm) with a reconstruction increment of 0.5 mm yields ~300 images. These are loaded into the MPR software. All images are reformatted at a thickness of 5.0 mm.
Patient history: 50 year old man with spontaneous intra- cranial hemorrhage 4 months prior to this scan with residual visual field deficit.
CT findings:Low attenuating area in right occipital lobe (arrows).
CT diagnosis: Sequelae from prior bleeding.