title: Automatic selection of tube potential for radiation dose reduction in vascular and contrast-enhanced abdominopelvic CT.
abstract: OBJECTIVE
  The purpose of this study is to assess the ability of a novel automatic tube potential selection tool to reduce radiation dose while maintaining diagnostic quality in CT angiography (CTA) and contrast-enhanced abdominopelvic CT.
  
  
  METHODS
  One hundred one CTA examinations and 90 contrastenhanced abdominopelvic examinations were performed using an automatic tube potential selection tool on a 128-MDCT scanner. Two vascular radiologists and two abdominal radiologists evaluated the image quality for sharpness, noise, artifact, and diagnostic confidence. In a subset of patients who had undergone prior studies (CTA, 28 patients; abdominopelvic CT, 25 patients), a side-by-side comparison was performed by a separate radiologist. Dose reduction and iodine contrast-to-noise ratio resulting from use of the tool were calculated.
  
  
  RESULTS
  For CTA, 80 or 100 kV was selected for 73% of the scans, with a mean dose reduction of 36% relative to the reference 120-kV protocol. For abdominopelvic CT examinations, 80 or 100 kV was used for 55% of the scans, with a mean dose reduction of 25%. Overall dose reduction relative to the reference 120-kV protocol was 25% and 13% for CTA and abdominopelvic CT scans, respectively. Over 98% of scans had acceptable sharpness, noise texture, artifact, and diagnostic confidence for both readers and diagnostic tasks; 94-100% of scans had acceptable noise. Iodine contrast-to-noise ratio was significantly higher than (p < 0.001) or similar to (p = 0.11) that of prior scans, and equivalent quality was achieved despite the dose reduction.
  
  
  CONCLUSIONS
  Automatic tube potential selection provides an efficient and quantitativeway to guide the selection of the optimal tube potential for CTA and abdominopelvic CT examinations.
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA. yu.lifeng@mayo.edu
authors.forename: Lifeng
authors.initials: L
authors.lastname: Yu
authors.forename: Joel G
authors.initials: JG
authors.lastname: Fletcher
authors.forename: Katharine L
authors.initials: KL
authors.lastname: Grant
authors.forename: Rickey E
authors.initials: RE
authors.lastname: Carter
authors.forename: David M
authors.initials: DM
authors.lastname: Hough
authors.forename: John M
authors.initials: JM
authors.lastname: Barlow
authors.forename: Terri J
authors.initials: TJ
authors.lastname: Vrtiska
authors.forename: Eric E
authors.initials: EE
authors.lastname: Williamson
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Young
authors.forename: Brian C
authors.initials: BC
authors.lastname: Goss
authors.forename: Maria
authors.initials: M
authors.lastname: Shiung
authors.forename: Shuai
authors.initials: S
authors.lastname: Leng
authors.forename: Ranier
authors.initials: R
authors.lastname: Raupach
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schmidt
authors.forename: Thomas
authors.initials: T
authors.lastname: Flohr
authors.forename: Cynthia H
authors.initials: CH
authors.lastname: McCollough
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods*; D016477:Artifacts; D001331:Automation; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011860:Radiography, Abdominal / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*
chemical_list: D003287:Contrast Media