Computed tomographic angiography: Historical perspective and new state-of-the-art using multi detector-row helical computed tomography

Since its clinical introduction in 1991, volumetric computed tomography sca nning using spiral or helical scanners has resulted in a revolution for dia gnostic imaging. In addition to new applications for computed tomography, s uch as computed tomographic angiography and the assessment of patients with renal colic, many routine applications such as the detection of lung and l iver lesions have substantially improved. Helical computed tomographic tech nology has improved over the past eight years with faster gantry rotation, more powerful X-ray tubes, and improved interpolation algorithms, but the g reatest advance has been the recent introduction of multi detector-row comp uted tomography scanners. These scanners provide similar scan quality at a speed gain of 3-6 times greater than single (detector-row computed tomograp hy scanners. This has a profound impact on the performance of computed tomo graphy angiography, resulting in greater anatomic coverage, lower iodinated contrast doses, and higher spatial resolution scans than single detector-r ow systems.