Myocardial delayed enhancement with dual-source CT: advantages of targeted spatial frequency filtration and image averaging over half-scan reconstruction

Yusuke Kurobe; Kakuya Kitagawa; Tatsuro Ito; Yoshie Kurita; Yasuyuki Shiraishi; Shiro Nakamori; Hiroshi Nakajima; Motonori Nagata; Masaki Ishida; Kaoru Dohi; Masaaki Ito; Hajime Sakuma

doi:10.1016/j.jcct.2014.06.004

Myocardial delayed enhancement with dual-source CT: advantages of targeted spatial frequency filtration and image averaging over half-scan reconstruction

J Cardiovasc Comput Tomogr. 2014 Jul-Aug;8(4):289-98. doi: 10.1016/j.jcct.2014.06.004. Epub 2014 Jun 17.

Affiliations

¹ Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 514-8507, Japan.
² Department of Radiology, Mie University School of Medicine, 2-174 Edobashi, Tsu 514-8507, Japan. Electronic address: kakuya@clin.medic.mie-u.ac.jp.
³ Department of Cardiology, Mie University School of Medicine, Tsu, Japan.

PMID: 25151921
DOI: 10.1016/j.jcct.2014.06.004

Abstract

Background: Clinical utility of myocardial delayed-enhancement CT is currently limited because of relatively poor contrast-to-noise ratio (CNR) and artifacts. Targeted spatial-frequency filtration (TSFF) is a hybrid algorithm of half- and full-scan reconstruction that can achieve both high temporal resolution and improved stability of myocardial signal.

Objective: The purpose of this study was to evaluate image quality of delayed-enhancement CT using TSFF with image averaging and its reproducibility in infarct assessment in comparison with conventional half-scan reconstruction (HALF).

Methods: Forty patients with suspected coronary artery disease underwent delayed-enhancement CT with HALF and TSFF using dual-source CT. Two blinded readers independently determined the presence and size of delayed enhancement. Image quality, signal-to-noise ratio and CNR were assessed. The presence of delayed enhancement on CT was compared with magnetic resonance imaging in 12 patients.

Results: TSFF with averaging of 4 image stacks acquired during 1 breathhold demonstrated significantly better image quality compared with HALF. Good left ventricular lumen-myocardium contrast was consistently achieved with TSFF in patients who received iodine dose of >600 mg I/kg. The signal-to-noise ratio and CNR were 11.3 ± 4.2 and 4.5 ± 1.6 by TSFF, being significantly higher than those by HALF (7.9 ± 2.9 and 3.3 ± 1.8; P < .01 for both). Interobserver reproducibility of infarct sizing was markedly improved by using TSFF instead of HALF (intraclass correlation coefficient: 0.86 vs 0.50). Agreement with magnetic resonance imaging by kappa statistics was 0.85 with TSFF and 0.74 with HALF.

Conclusions: TSFF with image averaging can significantly improve image quality of delayed-enhancement CT and considerably enhances interobserver reproducibility of infarct sizing.

Keywords: Cardiac-gated imaging techniques; Cardiovascular disease; Diagnostic imaging; Myocardial infarction; X-ray computed tomography.

Publication types

Comparative Study
Evaluation Study
Research Support, Non-U.S. Gov't

MeSH terms

Aged
Algorithms
Artifacts
Contrast Media
Coronary Angiography / methods*
Coronary Artery Disease / diagnostic imaging*
Female
Humans
Male
Middle Aged
Myocardial Infarction / diagnostic imaging*
Myocardial Perfusion Imaging / methods*
Observer Variation
Predictive Value of Tests
Radiographic Image Interpretation, Computer-Assisted*
Reproducibility of Results
Signal-To-Noise Ratio
Tomography, X-Ray Computed*

Substances

Contrast Media