A real number is a component of a complex number. In CT, complex data are used for example in the Fourier transforms.

A wide range of software techniques and advanced computer systems are developed that enable creation of three-dimensional images. Spiral CT allows the acquisition of CT data that is perfectly suited to 3D reconstruction. Advanced CT scanners image entire anatomic regions like the lungs in one breath hold and acquire a volume of data with the patient anatomy all in one position. This volume data is reconstructed to provide 3 dimensional pictures of for example complex blood vessels like the renal arteries or aorta. 3D reconstructions allow surgeons to visualize complex fractures in three dimensions and can help them plan reconstructive surgery.