Comparison between integrated backscatter intravascular ultrasound and 64-slice multi-detector row computed tomography for tissue characterization and volumetric assessment of coronary plaques

Takahiko Yamaki,Genzou Takemura,Kazuhiko Nishigaki,Ik-Kyung Jang,Hisayoshi Fujiwara,Tomoki Kubota,Shinya Minatoguchi,Owen Christopher Raffel,Yoshiyuki Ishihara,Munenori Okubo,Arihiro Hattori,Masanori Kawasaki

doi:10.1186/1476-7120-10-33

Abstract

BackgroundThe purpose of this study was to determine the cut-off values of Hounsfield units (HU) for the discrimination of plaque components and to evaluate the feasibility of measurement of the volume of plaque components using multi-detector row computed tomography (MDCT).MethodsCoronary lesions (125 lesions in 125 patients) were visualized by both integrated backscatter intravascular ultrasound (IB-IVUS) and 64-slice MDCT at the same site. The IB values were used as a gold standard to determine the cut off values of HU for the discrimination of plaque components.ResultsPlaques were classified as lipid pool (n =50), fibrosis (n =65) or calcification (n =35) by IB-IVUS. The HU of lipid pool, fibrosis and calcification were 18 ± 18 HU (−19 to 58 HU), 95 ± 24 HU (46 to 154 HU) and 378 ± 99 HU (188 to 605 HU), respectively. Using receiver operating characteristic curve analysis, a threshold of 50 HU was the optimal cutoff values to discriminate lipid pool from fibrosis. Lipid volume measured by MDCT was correlated with that measured by IB-IVUS (r =0.66, p <0.001), whereas fibrous volume was not (r =0.21, p =0.059).ConclusionLipid volume measured by MDCT was moderately correlated with that measured by IB-IVUS. MDCT may be useful for volumetric assessment of the lipid volume of coronary plaques, whereas the assessment of fibrosis volume was unstable.

Highlights

Enhanced multi-detector row computed tomography (MDCT) is a promising minimally-invasive method for detecting coronary artery disease
The ability of MDCT to characterize the tissue components of coronary plaques has been controversial, with some studies showing that MDCT produced results that were similar to conventional intravascular ultrasound (IVUS) [7,8], whereas other studies found that MDCT was not as accurate as IVUS [9,10]
We previously reported that integrated backscatter (IB)-IVUS had with high sensitivity and specificity (90-95 %) for the characterization of plaque tissue components using histology as a gold standard [13,14]

Summary

Introduction

Enhanced multi-detector row computed tomography (MDCT) is a promising minimally-invasive method for detecting coronary artery disease. This method uses low radiation and requires the intravenous injection of contrast medium. The ability of MDCT to characterize the tissue components of coronary plaques has been controversial, with some studies showing that MDCT produced results that were similar to conventional intravascular ultrasound (IVUS) [7,8], whereas other studies found that MDCT was not as accurate as IVUS [9,10]. The purpose of this study was to determine the cut-off values of Hounsfield units (HU) for the discrimination of plaque components and to evaluate the feasibility of measurement of the volume of plaque components using multi-detector row computed tomography (MDCT)

Objectives

Methods

Results

Conclusion