spiraaliskannaus

Spiraaliskannaus, also known as helical scanning or spiral scanning, is a technique used in various fields, notably in medical imaging and data acquisition. In medical imaging, it refers to the method by which a computed tomography (CT) scanner acquires data. Instead of moving the patient table back and forth, as in older axial scanning methods, the patient table moves continuously through the X-ray beam while the X-ray tube rotates around the patient. This allows for a continuous acquisition of data as the patient moves in a spiral or helical path. This method significantly speeds up the scanning process, leading to shorter breath-hold times for patients and reducing motion artifacts.

The principle of spiraaliskannaus is that the X-ray source and detectors rotate around the patient while the patient table moves linearly. This creates a helical path of data acquisition. Sophisticated interpolation algorithms are then used to reconstruct cross-sectional images from this helical data. This technique has become the standard for most modern CT scanners due to its efficiency and improved image quality.

Beyond medical imaging, spiraaliskannaus can also refer to the process of scanning a physical document or object in a spiral pattern, often for digitizing purposes or as part of a specialized scanning hardware. In these contexts, the scanner typically moves in an outward spiral from a central point, capturing data as it progresses. The underlying concept remains the continuous movement and data capture along a defined path.