title: Gallstone detection at CT in vitro: effect of peak voltage setting.
abstract: This study was a retrospective single-institutional study approved by the Committee on Human Research and was HIPAA compliant. A waiver for informed consent was granted. The purpose of the study was to evaluate the effect of four peak voltage settings on the in vitro conspicuity of gallstones in an anthropomorphic phantom at computed tomography (CT). An anthropomorphic phantom was scanned with (n = 86) or without (n = 85) gallstones at CT by using 80, 100, 120, and 140 kVp. The sensitivity for gallstone detection was significantly higher at 140 kVp (86% [74 of 86] for reader 1 and 81% [70 of 86] for reader 2) than at lower voltage settings (up to 67% [58 of 86] for reader 1 and 63% [54 of 86] for reader 2, P < .05 for each reader), regardless of gallstone size (<1.0 cm vs > or =1.0 cm in diameter, P < .05 for each reader). CT attenuation measurements were not useful for determination of gallstone composition. Abdominal CT performed at 140 kVp may be useful when gallstone disease is of clinical concern.
authors.affiliation: Department of Radiology, University of California San Francisco, 505 Parnassus Ave, San Francisco, CA 94143-0628, USA.
authors.forename: Wesley C
authors.initials: WC
authors.lastname: Chan
authors.forename: Bonnie N
authors.initials: BN
authors.lastname: Joe
authors.forename: Fergus V
authors.initials: FV
authors.lastname: Coakley
authors.forename: Edwin L
authors.initials: EL
authors.lastname: Prien
authors.forename: Robert G
authors.initials: RG
authors.lastname: Gould
authors.forename: Sven
authors.initials: S
authors.lastname: Prevrhal
authors.forename: William C
authors.initials: WC
authors.lastname: Barber
authors.forename: Kimberley S
authors.initials: KS
authors.lastname: Kirkwood
authors.forename: Aliya
authors.initials: A
authors.lastname: Qayyum
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Yeh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D042882:Gallstones / Q000000981:diagnostic imaging*; D006801:Humans; D066298:In Vitro Techniques; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D011860:Radiography, Abdominal; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*