ABSTRACT
COMPUTED TOMOGRAPHY Computed tomography (CT) is a cross-sectional X-ray imaging technique. Differentiation of structures is based on the varying roentgen attenuation of different tissues. Generated roentgen rays are emitted in the shape of a fan or cone from one side of the gantry. After passing through an object, the remaining photons are collected and measured by roentgen detectors on the opposite side. By measuring the (attenuation of the) roentgen a so-called projection is created. During rotation of the tube and detectors around the object, a large number of these projections are acquired. From these combined angular projections the variation of attenuation can be calculated throughout a cross-sectional plane using sophisticated image reconstruction algorithms.
