Automated Tube Potential Selection as a Method of Dose Reduction for CT of the Neck: First Clinical Results

作者：Bodelle Boris^*; Beeres Martin; Scheithauer Sebastian; Wichmann Julian L; Nour Eldin Nour Eldin Abdelrehim; Vogl Thomas J; Schulz Boris

来源：American Journal of Roentgenology, 2015, 204(5): 1049-1054.

DOI：10.2214/AJR.14.12975

• attenuation-based automated tube potential selection
• automated tube potential selection (ATPS)
• CT
• dose reduction
• neck CT
• radiation exposure

OBJECTIVE. The objective of our study was to investigate whether the use of a software-based automated tube potential selection (ATPS) CT neck protocol can result in radiation dose reduction as compared with a set 120-kV protocol without a statistically significant reduction in image quality.
MATERIALS AND METHODS. Three hundred sixty-four patients (median age, 52 years) underwent CT of the neck. Group 1 (n = 320) underwent CT with ATPS with 80, 100, or 120 kV. Group 2 (n = 44) was examined with the standard CT protocol at 120 kV. Attenuation, image background noise, signal-to-noise ratio (SNR), dose-length product (DLP), volume CT dose index (CTDIvol), body mass index (BMI [weight in kilograms divided by the square of height in meters]), and subjective image quality (5-point Likert scale, two readers in consensus) were analyzed.
RESULTS. A tube potential of 100 kV was selected in 279 patients, 120 kV in 40 patients, and 80 kV in one patient of the ATPS group. A significant correlation was found for selected tube potential and BMI (80 kV, BMI = 20.4; 100 kV, mean BMI = 24.2; 120 kV, BMI = 28.6; r = 0.28, p < 0.01). The average radiation dose was significantly lower with ATPS activated than with the standard protocol (mean DLP, 259 vs 350 mGy x cm, respectively). Background noise did not differ between groups 1 and 2 at the levels of the mandibular angle and the upper mediastinum; however, attenuation and SNR increased significantly with lower tube potential settings. Subjective image quality did not suffer (mean image quality score: ATPS protocol vs standard protocol, 4.56 vs 4.61, respectively; p > 0.05) with good interobserver agreement (kappa > 0.56).
CONCLUSION. ATPS allows significant dose savings for CT of the neck compared with a standard protocol that uses a fixed 120-kV setting without a statistically significant reduction in image quality.

• 出版日期2015-5