Atherosclerotic plaque imaging using phase-contrast X-ray computed tomography.
Reliable, noninvasive imaging modalities to characterize plaque components are clinically desirable for detecting unstable coronary plaques, which cause acute coronary syndrome. Although recent clinical developments in computed tomography (CT) have enabled the visualization of luminal narrowing and calcified plaques in coronary arteries, the identification of noncalcified plaque components remains difficult. Phase-contrast X-ray CT imaging has great potentials to reveal the structures inside biological soft tissues, because its sensitivity to light elements is almost 1,000 times greater than that of absorption-contrast X-ray imaging. Moreover, a specific mass density of tissue can be estimated using phase-contrast X-ray CT. Ex vivo phase-contrast X-ray CT was performed using a synchrotron radiation source (SPring-8, Japan) to investigate atherosclerotic plaque components of apolipoprotein E-deficient mice. Samples were also histologically analyzed. Phase-contrast X-ray CT at a spatial resolution of 10-20 mum revealed atherosclerotic plaque components easily, and thin fibrous caps were detected. The specific mass densities of these plaque components were quantitatively estimated. The mass density of lipid area was significantly lower (1.011 +/- 0.001766 g/ml) than that of smooth muscle area or collagen area (1.057 +/- 0.001407 and 1.080 +/- 0.001794 g/ml, respectively). Moreover, the three-dimensional assessment of plaques could provide their anatomical information. Phase-contrast X-ray CT can estimate the tissue mass density of atherosclerotic plaques and detect lipid-rich areas. It can be a promising noninvasive technique for the investigation of plaque components and detection of unstable coronary plaques.
Shinohara
Masakazu
M
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
Yamashita
Tomoya
T
Tawa
Hideto
H
Takeda
Masafumi
M
Sasaki
Naoto
N
Takaya
Tomofumi
T
Toh
Ryuji
R
Takeuchi
Akihisa
A
Ohigashi
Takuji
T
Shinohara
Kunio
K
Kawashima
Seinosuke
S
Yokoyama
Mitsuhiro
M
Hirata
Ken-ichi
K
Momose
Atsushi
A
D000818:Animals; D001057:Apolipoproteins E / Q000235:genetics; D050197:Atherosclerosis / Q000000981:diagnostic imaging* / Q000473:pathology; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology; D002791:Cholesterol, Dietary / Q000494:pharmacology; D003331:Coronary Vessels / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009206:Myocardium / Q000473:pathology; D017356:Synchrotrons; D014057:Tomography, X-Ray Computed / Q000379:methods*
D001057:Apolipoproteins E; D002791:Cholesterol, Dietary