Dynamic low-dose three-dimensional computed tomography: a preliminary study

Abstract

Three-dimensional (3D) computed tomographic reformations have been used successfully as an adjunct to standard axial computed tomography (CT) in the evaluation of disorders affecting areas of complex anatomy. The basic requirements for high-quality 3D reformations are an absence of patient movement and narrow-width transaxial sections. Speed of examination is an important factor in optimizing image quality. One hundred examinations were performed on an IGE CT 9800 scanner. For bone studies, 80 mAs and, for certain soft tissues, 140 or 200 mAs were employed with 120 kVp. The advantages of such a "low-dose" technique are significant reduction in patient skin dose and a faster examination. The main disadvantage is a reduction in signal-to-noise ratio. The image quality obtained in 3D presentations has nevertheless been sufficient to enable all bony abnormalities to be identified. Three-dimensional examinations are now being performed routinely using a dynamic mode and this "low-dose" technique.