[CT examinations using a reduced radiation dosage].

An experimental method was used to determine which diagnostic CT problems could be solved while using reduced radiation doses. The examinations were carried out using 85 kv and 1.7 to 3.0 mGy (instead of the usual 125 kv and 20 to 50 mGy). More than 500 patients have been investigated so far. The method has been used successfully for bone mineral estimations and for otorhinologic and orthopaedic problems. All examinations with high contrast (bones, sinuses) and small diameters (extremities) produced adequate images compared with the usual pictures. With the exception of cerebral CT for demonstrating the brain (structures with little contrast), the method can also be used for children and infants. During the first phase of this study the role of this method has been evaluated. Subjective impressions and demonstration of detail, when compared with a 'normal' image for a corresponding cut, were satisfactory. Signal-to-noise ratio was measured by a quantifiable parameter of image quality.