J B Hartman1, S Moran1, C Zhu1, J Sharp1, D S Hippe2, D A Zamora1, M Mossa-Basha3,4. 1. From the Department of Radiology (J.B.H., S.M., C.Z., J.S., D.A.Z., M.M.-B.), University of Washington, Seattle, Washington. 2. Clinical Research Division (D.S.H.), Fred Hutchinson Cancer Research Center, Seattle, Washington. 3. From the Department of Radiology (J.B.H., S.M., C.Z., J.S., D.A.Z., M.M.-B.), University of Washington, Seattle, Washington mmossab@uw.edu. 4. Department of Radiology (M.M.-B.), University of North Carolina, Chapel Hill, North Carolina.
Abstract
BACKGROUND AND PURPOSE: Contrast curve truncation in CTP protocols may introduce errors. We sought to identify risk factors and design a protocol to avoid truncation while limiting radiation. MATERIALS AND METHODS: In an initial fixed-timing cohort, patients underwent a 65-second CTP with 2-second delay postcontrast injection. Multivariable analysis identified factors associated with truncation. A later case-specific cohort underwent either the original protocol or a low cardiac output protocol with a 7-second delay and 75-second scanning window, with selection determined by CTA test-dose enhancement upswing delay. Time-density curves were assessed for truncation and compared between the 2 groups, and the radiation dose was evaluated. RESULTS: From September 2017 through May 2018, one hundred fifty-three patients underwent the standard fixed-timing protocol. Age (OR, 1.82/10-year increase; P = .019), reduced left ventricle ejection fraction (OR, 9.23; P = .001), and hypertension (OR, 0.32; P = .06) were independently associated with truncation in an exploratory multivariable model. From May 2018 through April 2019, one hundred fifty-seven patients underwent either the standard (72 patients) or low cardiac output protocol (85 patients). The fixed-timing cohort had 15 truncations (9.8%) versus 4 in the case-specific cohort (2.5%; P = .009). If the low cardiac output protocol were applied to those with >10.6% predicted risk of truncation based on age, left ventricle ejection fraction, and hypertension, the number of truncations would have decreased from 15 to 4 in the fixed-timing cohort. CONCLUSIONS: Older age, left ventricle ejection fraction, and the absence of hypertension increase the risk of time-density curve truncation. However, a CTA test-dose-directed case-specific protocol can reduce truncation to ensure accurate data while mitigating radiation dose increases.
BACKGROUND AND PURPOSE: Contrast curve truncation in CTP protocols may introduce errors. We sought to identify risk factors and design a protocol to avoid truncation while limiting radiation. MATERIALS AND METHODS: In an initial fixed-timing cohort, patients underwent a 65-second CTP with 2-second delay postcontrast injection. Multivariable analysis identified factors associated with truncation. A later case-specific cohort underwent either the original protocol or a low cardiac output protocol with a 7-second delay and 75-second scanning window, with selection determined by CTA test-dose enhancement upswing delay. Time-density curves were assessed for truncation and compared between the 2 groups, and the radiation dose was evaluated. RESULTS: From September 2017 through May 2018, one hundred fifty-three patients underwent the standard fixed-timing protocol. Age (OR, 1.82/10-year increase; P = .019), reduced left ventricle ejection fraction (OR, 9.23; P = .001), and hypertension (OR, 0.32; P = .06) were independently associated with truncation in an exploratory multivariable model. From May 2018 through April 2019, one hundred fifty-seven patients underwent either the standard (72 patients) or low cardiac output protocol (85 patients). The fixed-timing cohort had 15 truncations (9.8%) versus 4 in the case-specific cohort (2.5%; P = .009). If the low cardiac output protocol were applied to those with >10.6% predicted risk of truncation based on age, left ventricle ejection fraction, and hypertension, the number of truncations would have decreased from 15 to 4 in the fixed-timing cohort. CONCLUSIONS: Older age, left ventricle ejection fraction, and the absence of hypertension increase the risk of time-density curve truncation. However, a CTA test-dose-directed case-specific protocol can reduce truncation to ensure accurate data while mitigating radiation dose increases.
Authors: Emelia J Benjamin; Michael J Blaha; Stephanie E Chiuve; Mary Cushman; Sandeep R Das; Rajat Deo; Sarah D de Ferranti; James Floyd; Myriam Fornage; Cathleen Gillespie; Carmen R Isasi; Monik C Jiménez; Lori Chaffin Jordan; Suzanne E Judd; Daniel Lackland; Judith H Lichtman; Lynda Lisabeth; Simin Liu; Chris T Longenecker; Rachel H Mackey; Kunihiro Matsushita; Dariush Mozaffarian; Michael E Mussolino; Khurram Nasir; Robert W Neumar; Latha Palaniappan; Dilip K Pandey; Ravi R Thiagarajan; Mathew J Reeves; Matthew Ritchey; Carlos J Rodriguez; Gregory A Roth; Wayne D Rosamond; Comilla Sasson; Amytis Towfighi; Connie W Tsao; Melanie B Turner; Salim S Virani; Jenifer H Voeks; Joshua Z Willey; John T Wilkins; Jason Hy Wu; Heather M Alger; Sally S Wong; Paul Muntner Journal: Circulation Date: 2017-01-25 Impact factor: 29.690
Authors: Gregory W Albers; Michael P Marks; Stephanie Kemp; Soren Christensen; Jenny P Tsai; Santiago Ortega-Gutierrez; Ryan A McTaggart; Michel T Torbey; May Kim-Tenser; Thabele Leslie-Mazwi; Amrou Sarraj; Scott E Kasner; Sameer A Ansari; Sharon D Yeatts; Scott Hamilton; Michael Mlynash; Jeremy J Heit; Greg Zaharchuk; Sun Kim; Janice Carrozzella; Yuko Y Palesch; Andrew M Demchuk; Roland Bammer; Philip W Lavori; Joseph P Broderick; Maarten G Lansberg Journal: N Engl J Med Date: 2018-01-24 Impact factor: 91.245
Authors: Raul G Nogueira; Ashutosh P Jadhav; Diogo C Haussen; Alain Bonafe; Ronald F Budzik; Parita Bhuva; Dileep R Yavagal; Marc Ribo; Christophe Cognard; Ricardo A Hanel; Cathy A Sila; Ameer E Hassan; Monica Millan; Elad I Levy; Peter Mitchell; Michael Chen; Joey D English; Qaisar A Shah; Frank L Silver; Vitor M Pereira; Brijesh P Mehta; Blaise W Baxter; Michael G Abraham; Pedro Cardona; Erol Veznedaroglu; Frank R Hellinger; Lei Feng; Jawad F Kirmani; Demetrius K Lopes; Brian T Jankowitz; Michael R Frankel; Vincent Costalat; Nirav A Vora; Albert J Yoo; Amer M Malik; Anthony J Furlan; Marta Rubiera; Amin Aghaebrahim; Jean-Marc Olivot; Wondwossen G Tekle; Ryan Shields; Todd Graves; Roger J Lewis; Wade S Smith; David S Liebeskind; Jeffrey L Saver; Tudor G Jovin Journal: N Engl J Med Date: 2017-11-11 Impact factor: 91.245