The helical (spiral) scans are used to see details of the organs and structures located in the chest. Most modern hospitals currently use CT scanners since the early 2000's.The term spiral was preferred by Willi Kalender, the inventor of the helical CT scan, and it means the same thing.

A helical chest CT scan is practically a detailed picture that results after a scan of the chest with the help of x-ray beams. The patient lies on a slowly-moving table inside the tunnel-shaped machine while an x-ray beam rotates in a spiral path around the body. The data collected by x-rays are used by the computer to create series of pictures – called slices. The many slices are processed into very detailed, 3D pictures of the lungs and other structures inside the chest.