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European Radiology

, Volume 19, Issue 8, pp 1914–1922 | Cite as

Is body weight the most appropriate criterion to select patients eligible for low-dose pulmonary CT angiography? Analysis of objective and subjective image quality at 80 kVp in 100 patients

  • Zsolt Szucs-Farkas
  • Tamara Strautz
  • Michael A. PatakEmail author
  • Luzia Kurmann
  • Peter Vock
  • Sebastian T. Schindera
Chest

Abstract

The objective of this retrospective study was to assess image quality with pulmonary CT angiography (CTA) using 80 kVp and to find anthropomorphic parameters other than body weight (BW) to serve as selection criteria for low-dose CTA. Attenuation in the pulmonary arteries, anteroposterior and lateral diameters, cross-sectional area and soft-tissue thickness of the chest were measured in 100 consecutive patients weighing less than 100 kg with 80 kVp pulmonary CTA. Body surface area (BSA) and contrast-to-noise ratios (CNR) were calculated. Three radiologists analyzed arterial enhancement, noise, and image quality. Image parameters between patients grouped by BW (group 1: 0–50 kg; groups 2–6: 51–100 kg, decadally increasing) were compared. CNR was higher in patients weighing less than 60 kg than in the BW groups 71–99 kg (P between 0.025 and <0.001). Subjective ranking of enhancement (P = 0.165–0.605), noise (P = 0.063), and image quality (P = 0.079) did not differ significantly across all patient groups. CNR correlated moderately strongly with weight (R = −0.585), BSA (R = −0.582), cross-sectional area (R = −0.544), and anteroposterior diameter of the chest (R = −0.457; P < 0.001 all parameters). We conclude that 80 kVp pulmonary CTA permits diagnostic image quality in patients weighing up to 100 kg. Body weight is a suitable criterion to select patients for low-dose pulmonary CTA.

Keywords

Pulmonary CT angiography Radiation exposure Image quality 

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Copyright information

© European Society of Radiology 2009

Authors and Affiliations

  • Zsolt Szucs-Farkas
    • 1
  • Tamara Strautz
    • 1
  • Michael A. Patak
    • 1
    Email author
  • Luzia Kurmann
    • 1
  • Peter Vock
    • 1
  • Sebastian T. Schindera
    • 1
  1. 1.Department of Diagnostic, Interventional and Paediatric RadiologyUniversity Hospital and University of BerneBerneSwitzerland

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