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Titel:

Step and shoot coronary CT angiography using 256-slice CT: effect of heart rate and heart rate variability on image quality.

Dokumenttyp:
journal article
Autor(en):
Muenzel, D; Noel, PB; Dorn, F; Dobritz, M; Rummeny, EJ; Huber, A
Abstract:
To evaluate the effect of heart rate variability (HRV) and heart rate (HR) on intra-image "motion" and inter-image "stairstep" artefacts in step-and-shoot coronary CT angiography (CCTA) using a wide detector CT scanner.66 patients underwent step-and-shoot CCTA using 256-slice CT. Patients were divided into two groups (Group 1: HR<65 bpm, Group 2>>=65bpm). Motion artefacts were quantified using a 5-point-scale. Stairstep artefacts were defined by measurements of misalignment. Image noise, contrast-to-noise-ratio (CNR), signal-to-noise-ratio (SNR), and radiation dose were assessed.Mean HR was 66 ± 16.7 bpm (range: 45-125 bpm) and mean HRV was 10.7 ± 17.5 bpm. A significant correlation between HR and stairstep artefacts (r = 0.46, p< 0.001) and motion artefacts (r = 0.63, p< 0.001) was found. Group 2 showed significantly increased step artefacts with a mean misalignment of 1.4 mm compared to 0.4 mm in Group 1 (p< 0.001). There was no significant effect of HRV on stairstep artefacts (r = 0.15, p = 0.416) and motion artefacts (r = 0.13, p = 0.311). No significant differences in image noise, CNR, SNR, and radiation dose were seen.Unlike CCTA using narrow CT detectors, HRV has no significant effect on motion and stairstep artefacts using a wide CT detector with high z-coverage. However, a higher HR still increases stairstep and motion artefacts.
Zeitschriftentitel:
Eur Radiol
Jahr:
2011
Band / Volume:
21
Heft / Issue:
11
Seitenangaben Beitrag:
2277-84
Sprache:
eng
PubMed:
http://view.ncbi.nlm.nih.gov/pubmed/21710267
Print-ISSN:
0938-7994
TUM Einrichtung:
Röntgendiagnostik
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