title: Radiation exposure in the follow-up of patients with urolithiasis comparing digital tomosynthesis, non-contrast CT, standard KUB, and IVU.
abstract: OBJECTIVE
  To compare the effective doses (EDs) associated with imaging modalities for follow-up of patients with urolithiasis, including stone protocol non-contrast computed tomography (NCCT), kidney, ureter, and bladder radiograph (KUB), intravenous urogram (IVU), and digital tomosynthesis (DT).
  
  
  METHODS
  A validated Monte-Carlo simulation-based software PCXMC 2.0 (STUK) designed for estimation of patient dose from medical X-ray exposures was used to determine the ED for KUB, IVU (KUB scout plus three tomographic images), and DT (two scouts and one tomographic sweep). Simulations were performed using a two-dimensional stationary field onto the corresponding body area of the built-in digital phantom, with actual kVp, mAs, and geometrical parameters of the protocols. The ED for NCCT was determined using an anthropomorphic male phantom that was placed prone on a 64-slice GE Healthcare volume computed tomography (VCT) scanner. High-sensitivity metal oxide semiconductor field effect transistors dosimeters were placed at 20 organ locations and used to measure organ radiation doses.
  
  
  RESULTS
  The ED for a stone protocol NCCT was 3.04±0.34 mSv. The ED for a KUB was 0.63 and 1.1 mSv for the additional tomographic film. The total ED for IVU was 3.93 mSv. The ED for DT performed with two scouts and one sweep (14.2°) was 0.83 mSv.
  
  
  CONCLUSIONS
  Among the different imaging modalities for follow-up of patients with urolithiasis, DT was associated with the least radiation exposure (0.83 mSv). This ED corresponds to a fifth of NCCT or IVU studies. Further studies are needed to demonstrate the sensitivity and specificity of DT for the follow-up of nephrolithiasis patients.
authors.affiliation: 1 Division of Urologic Surgery, Duke University Medical Center , Durham, North Carolina.
authors.forename: Gaston M
authors.initials: GM
authors.lastname: Astroza
authors.forename: Andreas
authors.initials: A
authors.lastname: Neisius
authors.forename: Agnes J
authors.initials: AJ
authors.lastname: Wang
authors.forename: Giao
authors.initials: G
authors.lastname: Nguyen
authors.forename: Greta
authors.initials: G
authors.lastname: Toncheva
authors.forename: Chu
authors.initials: C
authors.lastname: Wang
authors.forename: Natalie
authors.initials: N
authors.lastname: Januzis
authors.forename: Carolyn
authors.initials: C
authors.lastname: Lowry
authors.forename: Michael N
authors.initials: MN
authors.lastname: Ferrandino
authors.forename: Amy N
authors.initials: AN
authors.lastname: Neville
authors.forename: Terry T
authors.initials: TT
authors.lastname: Yoshizumi
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Preminger
authors.forename: Michael E
authors.initials: ME
authors.lastname: Lipkin
mesh_terms: D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014567:Urography / Q000379:methods*; D052878:Urolithiasis / Q000000981:diagnostic imaging*