Axelle Franken1, Pierre Alain Gevenois1, Alain Van Muylem2, Nigel Howarth3, Caroline Keyzer1. 1. 1 Department of Radiology, Hôpital Erasme, Université Libre de Bruxelles, Route de Lennik 808, Brussels B-1070, Belgium. 2. 2 Department of Pneumology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium. 3. 3 Department of Radiology, Clinique des Grangettes-Genève, Chêne-Bougeries, Switzerland.
Abstract
OBJECTIVE: The objective of our study was to evaluate in vivo urinary calculus characterization with third-generation dual-source dual-energy CT (DECT) at reduced versus standard radiation dose. SUBJECTS AND METHODS: One hundred fifty-three patients requiring unenhanced CT for suspected or known urolithiasis were prospectively included in our study. They underwent two acquisitions at reduced-dose CT (90 kV and 50 mAsref; Sn150 kV and 31 mAsref, where Sn denotes the interposition of a tin filter in the high-energy beam) and standard-dose CT (90 kV and 50 mAsref; Sn150 kV and 94 mAsref). One radiologist interpreted the reduced-dose examinations before the standard-dose examinations during the same session. Among 103 patients (23 women, 80 men; mean age ± SD, 50 ± 15 years; age range, 18-82 years) with urolithiasis, dedicated DECT software measured the maximal diameter and CT numbers, calculated the DECT number ratio, and labeled with a color code each calculus visualized by the radiologist as uric acid (UA) or non-UA. Volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded. RESULTS: The radiologist visualized 279 calculi on standard-dose CT and 262 on reduced-dose CT; 17 calculi were missed on reduced-dose CT, all of which were ≤ 3 mm. Among the 262 calculi visualized at both doses, the CT number ratio was obtained with the software for 227 calculi and was not different between the doses (p = 0.093). Among these 262 calculi, 197 were labeled at both doses; 194 of the 197 labeled calculi were labeled with the same color code. Among the 65 remaining calculi, 48 and 61 (all ≤ 5 mm) were not labeled at standard-dose and reduced-dose CT (p = 0.005), respectively. At reduced-dose CT, the mean CTDIvol was 2.67 mGy and the mean DLP was 102.2 mGy × cm. CONCLUSION: With third-generation dual-source DECT, a larger proportion of calculi ≤ 5 mm are not characterized as UA or non-UA at a reduced dose.
OBJECTIVE: The objective of our study was to evaluate in vivo urinary calculus characterization with third-generation dual-source dual-energy CT (DECT) at reduced versus standard radiation dose. SUBJECTS AND METHODS: One hundred fifty-three patients requiring unenhanced CT for suspected or known urolithiasis were prospectively included in our study. They underwent two acquisitions at reduced-dose CT (90 kV and 50 mAsref; Sn150 kV and 31 mAsref, where Sn denotes the interposition of a tin filter in the high-energy beam) and standard-dose CT (90 kV and 50 mAsref; Sn150 kV and 94 mAsref). One radiologist interpreted the reduced-dose examinations before the standard-dose examinations during the same session. Among 103 patients (23 women, 80 men; mean age ± SD, 50 ± 15 years; age range, 18-82 years) with urolithiasis, dedicated DECT software measured the maximal diameter and CT numbers, calculated the DECT number ratio, and labeled with a color code each calculus visualized by the radiologist as uric acid (UA) or non-UA. Volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded. RESULTS: The radiologist visualized 279 calculi on standard-dose CT and 262 on reduced-dose CT; 17 calculi were missed on reduced-dose CT, all of which were ≤ 3 mm. Among the 262 calculi visualized at both doses, the CT number ratio was obtained with the software for 227 calculi and was not different between the doses (p = 0.093). Among these 262 calculi, 197 were labeled at both doses; 194 of the 197 labeled calculi were labeled with the same color code. Among the 65 remaining calculi, 48 and 61 (all ≤ 5 mm) were not labeled at standard-dose and reduced-dose CT (p = 0.005), respectively. At reduced-dose CT, the mean CTDIvol was 2.67 mGy and the mean DLP was 102.2 mGy × cm. CONCLUSION: With third-generation dual-source DECT, a larger proportion of calculi ≤ 5 mm are not characterized as UA or non-UA at a reduced dose.
Authors: Vasiliki Chatzaraki; Alessandra Bolsi; Rahel A Kubik-Huch; Bernhard Schmidt; Antony John Lomax; Damien C Weber; Michael Thali; Tilo Niemann Journal: In Vivo Date: 2022 Mar-Apr Impact factor: 2.155
Authors: Tim Nestler; Kai Nestler; Andreas Neisius; Hendrik Isbarn; Christopher Netsch; Stephan Waldeck; Hans U Schmelz; Christian Ruf Journal: World J Urol Date: 2018-08-03 Impact factor: 4.226
Authors: C Seitz; T Bach; M Bader; W Berg; T Knoll; A Neisius; C Netsch; M Nothacker; S Schmidt; M Schönthaler; R Siener; R Stein; M Straub; W Strohmaier; C Türk; B Volkmer Journal: Urologe A Date: 2019-11 Impact factor: 0.639