[An anatomically adapted variation of the tube current in CT. Studies on radiation dosage reduction and image quality].
OBJECTIVE
To assess the impact of a method for anatomically adapted tube current variation. The resulting CT image quality was evaluated quantitatively and qualitatively.


METHODS
CT scans of 100 patients were performed with a constant tube current (Group 1) and another 100 patients with an anatomically adapted tube current (Group 2). The CT tube current was varied during a 360 degrees tube rotation reflecting the measured density values extracted from two perpendicular scout views. The standard deviation of densities of defined regions was measured. The image quality was ranked (1 = non-diagnostic-5 = excellent) by three radiologists.


RESULTS
The effective tube current could be reduced by an average of 8.9% (0-20.4%). The mean tube current reduction depended on the body region: pelvis (13.2%), abdomen (8.4%) and thorax (3.3%). The image quality was not significantly reduced in Group 2.


CONCLUSIONS
The method for anatomically adapted tube current variation leads especially in the pelvis to a significant mAs reduction without considerable loss of image quality.
Abteilung Röntgendiagnostik I, Georg-August-Universität Göttingen.
L
L
Kopka
M
M
Funke
N
N
Breiter
K P
KP
Hermann
R
R
Vosshenrich
E
E
Grabbe
D000368:Aged; D006801:Humans; D008875:Middle Aged; D015588:Observer Variation; D010384:Pelvic Bones / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D011786:Quality Control; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods* / Q000592:standards; D011860:Radiography, Abdominal; D013902:Radiography, Thoracic / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data
Anatomisch adaptierte Variation des Röhrenstroms bei der CT. Untersuchungen zur Strahlendosisreduktion und Bildqualität.