title: High-definition computed tomography for coronary artery stents: image quality and radiation doses for low voltage (100 kVp) and standard voltage (120 kVp) ECG-triggered scanning.
abstract: The noninvasive assessment of coronary stents by coronary CT angiography (CCTA) is an attractive method. However, the radiation dose associated with CCTA remains a concern for patients. The purpose of this study is to compare the radiation doses and image qualities of CCTA performed using tube voltages of 100 or 120 kVp for the evaluation of coronary stents. After receiving institutional review board approval, 53 consecutive patients with previously implanted stents (101 stents) underwent 64-slice CCTA. Patients were divided into three different protocol groups, namely, prospective ECG triggering at 100 kVp, prospective ECG triggering at 120 kVp, or retrospective gating at 100 kVp. Two reviewers qualitatively scored the quality of the resulting images for coronary stents and determined levels of artificial lumen narrowing (ALN), stent lumen attenuation increase ratio (SAIR), image noise, and radiation dose parameters. No significant differences were found between the three protocol groups concerning qualitative image quality or SAIR. Coronary lumen attenuation and in-stent attenuation of 100 kVp prospective CCTA (P-CCTA) were higher than in the 120 kVp P-CCTA protocol (all Ps < 0.001). Mean ALN was significantly lower for 100 kVp P-CCTA than for 100 kVp retrospective CCTA (R-CCTA, P = 0.007). The mean effective radiation dose was significantly lower (P < 0.001) for 100 kVp P-CCTA (3.3 ± 0.4 mSv) than for the other two protocols (100 kVp R-CCTA 6.7 ± 1.0 mSv, 120 kVp P-CCTA 4.6 ± 1.2 mSv). We conclude that the use of 100 kVp P-CCTA can reduce radiation doses for patients while maintaining the imaging quality of 100 kVp R-CCTA and 120 kVp P-CCTA for the evaluation of coronary stents.
authors.affiliation: Department of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, #1-10 Ami-Dong, Seo-Gu, Pusan, 602-739, Republic of Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Chang Won
authors.initials: CW
authors.lastname: Kim
authors.forename: Han Cheol
authors.initials: HC
authors.lastname: Lee
authors.forename: Ming-Ting
authors.initials: MT
authors.lastname: Wu
authors.forename: Lee
authors.initials: L
authors.lastname: Hwangbo
authors.forename: Ki Seok
authors.initials: KS
authors.lastname: Choo
authors.forename: June Hong
authors.initials: JH
authors.lastname: Kim
authors.forename: Ki-Nam
authors.initials: KN
authors.lastname: Lee
authors.forename: Jin You
authors.initials: JY
authors.lastname: Kim
authors.forename: Yeon Joo
authors.initials: YJ
authors.lastname: Jeong
mesh_terms: D000328:Adult; D000368:Aged; D055424:Cardiac-Gated Imaging Techniques; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000628:therapy*; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000209:etiology; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D015588:Observer Variation; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000295:instrumentation*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D015607:Stents; D016896:Treatment Outcome