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ABSTRACT: Unexpected breast uptake was observed in a 32-year-old woman referred for evaluation of hypertrophic cardiomyopathy. Diffuse
and marked bilateral breast uptake of123I-BMIPP and99mTc-TF was shown by both planar and SPECT imaging during the first study, and the uptake of both radionuclides had decreased
significantly eleven months later. At the time of the first radionuclide examination, she was occasionally breast feeding
her 2-year-old child and had small amounts of milk production. At the follow up examination, the frequency of breast feeding
was significantly reduced and she produced only small amounts of milk. Therefore, the uptake of123I-BMIPP and99mTc-TF may have been caused by lactation.
Annals of Nuclear Medicine 04/2012; 14(4):315-318. · 1.50 Impact Factor
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ABSTRACT: Fluorescent X-ray computed tomography (FXCT) enables us to reveal the cross-sectional distribution of very low concentration of specific elements, e.g. I, Gd, or Au, in biomedical samples at a spatial resolution of several hundred micrometers, and it has been used to evaluate the states of cerebral perfusion and fatty acid metabolic function of small animals in vivo and ex vivo. However, since the current system employs the data-acquisition scheme of the first-generation type of CT, it requires a huge amount of time to obtain a whole set of projections. In order to overcome the problem, we propose a novel imaging geometry using a sheet incident beam. We performed a proof-of-concept experiment using a preliminary imaging system constructed at beam line BLNE-5A, KEK. The efficacy of the proposed method is demonstrated by the reconstructed images of a physical phantom containing various concentrations of iodine solution and a mouse brain that is extracted after intravenous injection of 127I-IMP for observing the cerebral perfusion and then fixed with formalin. Copyright © 2009 John Wiley & Sons, Ltd.
X-Ray Spectrometry 05/2009; 38(5):439 - 445. · 1.45 Impact Factor
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ABSTRACT: X-ray crystal interferometer-based X-ray phase-contrast microtomography (phase-contrast microtomography) is able to image microstructures within soft tissue without the use of a contrast agent. Here we determined the feasibility of using this technique in the non-destructive inspection of formalin-fixed kidney tissue from certain hamsters that spontaneously develop mesangial thickening with focal and segmental glomerulosclerosis, and from age-matched Syrian hamsters. We used a triple Laue-case X-ray interferometer with a 40 microm-thick analyzer, a sample cell, and an X-ray charge-coupled-device camera with a 4.34 microm pixel size. Images of glomeruli and tubular structures were similar to those seen using 40-100 x magnification on an optical microscope. In samples from two female glomerulosclerotic hamsters, seven scattered lesions were detected. The wedge-shaped pathological lesions included mild atrophic tubular walls, markedly dilated tubular lumen, high-density glomeruli, and widening of Bowman's space. The microvasculature was distinctly visualized in the specimens without any contrast agents. Hence, phase-contrast microtomography can detect small scattered lesions in diseased kidney tissue and is a powerful auxiliary tool for pre-histological evaluations.
Kidney International 03/2009; 75(9):945-51. · 6.61 Impact Factor
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ABSTRACT: We propose a fluorescent x-ray computed tomography method using an array of detectors with an incident sheet beam, aimed at providing molecular imaging with high sensitivity and good spatial resolution. In this study, we prove the feasibility of this concept and investigate its imaging properties, including spatial and contrast resolutions and quantitativeness, by imaging an acrylic phantom and a normal mouse brain using a preliminary imaging system with monochromatic synchrotron x rays.
Optics Letters 12/2008; 33(21):2494-6. · 3.40 Impact Factor
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ABSTRACT: High sensitive synchrotron X-ray imaging techniques such as phase-contrast X-ray computed tomography with an X-ray interferometer (p-CT) and fluorescent X-ray computer tomography (FXCT) have been developed for biomedical researches. In this study, formalin fixed cardiac specimens of normal and cardiomyopathy hamsters were imaged to examine the feasibility of these imaging techniques. P-CT revealed the detailed morphological structures of heart such as myocardial density change, wall thickness and ventricular cavity, whereas FXCT demonstrated myocardial fatty acid metabolic impairment by using non-radioactive 1-127 labeled BMIPP. Even in younger 8-weeks-old cardiomyopathic hamster, the metabolic impairment was clearly revealed. Myocardial density and BMIPP uptake was analyzed quantitatively. Our results suggest these techniques have high sensitivity in density change and spatial resolution, and they are quite useful for myocardial biomedical research in small animals.
Noninvasive Functional Source Imaging of the Brain and Heart and the International Conference on Functional Biomedical Imaging, 2007. NFSI-ICFBI 2007. Joint Meeting of the 6th International Symposium on; 11/2007
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Tadanori Fukami,
Hidenori Sato,
Jin Wu, Thet-Thet- Lwin,
Tetsuya Yuasa,
Satoru Kawano,
Keiji Iida,
Takao Akatsuka,
Hidekata Hontani,
Tohoru Takeda,
Masao Tamura,
Hiroshi Yokota
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ABSTRACT: Our study aimed to quantitatively evaluate blood flow in the left ventricle (LV) of apical hypertrophic cardiomyopathy (APH) by combining wall thickness obtained from cardiac magnetic resonance imaging (MRI) and myocardial perfusion from single-photon emission computed tomography (SPECT). In this study, we considered paired MRI and myocardial perfusion SPECT from ten patients with APH and ten normals. Myocardial walls were detected using a level set method, and blood flow per unit myocardial volume was calculated using 3D surface-based registration between the MRI and SPECT images. We defined relative blood flow based on the maximum in the whole myocardial region. Accuracies of wall detection and registration were around 2.50 mm and 2.95 mm, respectively. We finally created a bull's-eye map to evaluate wall thickness, blood flow (cardiac perfusion) and blood flow per unit myocardial volume. In patients with APH, their wall thicknesses were over 10 mm. Decreased blood flow per unit myocardial volume was detected in the cardiac apex by calculation using wall thickness from MRI and blood flow from SPECT. The relative unit blood flow of the APH group was 1/7 times that of the normals in the apex. This normalization by myocardial volume distinguishes cases of APH whose SPECT images resemble the distributions of normal cases.
Physics in Medicine and Biology 08/2007; 52(14):4311-30. · 2.83 Impact Factor
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ABSTRACT: Fluorescent X-ray computed tomography (FXCT) using synchrotron radiation reveals the cross-sectional distribution of specific elements in biomedical objects. The aim of this study was to investigate the feasibility of FXCT imaging to assess the myocardial metabolic state quantitatively. Hearts labelled with non-radioactive iodine myocardial fatty acid agent 15-p-(iodophenyl)-3-methylpentadecanoic acid (BMIPP) from cardiomyopathic and normal hamsters were imaged. FXCT images were compared with optical microscope images. Myocardial fatty acid metabolism enhanced with BMIPP was clearly depicted by FXCT, which showed an almost homogeneous image for normal and a heterogeneous image for cardiomyopathic hearts. Morphological structures of the heart such as the left ventricle and myocardial wall were also visualized by FXCT. Optical microscopy showed no fibrosis in normal and slight interstitial fibrosis in cardiomyopathic hearts. In the case of cardiomyopathy, the area of significantly reduced BMIPP uptake was 39% in the short axis of the mid-left ventricle in the FXCT image, whereas a slight interstitial fibrosis of around 12% was recognized by optical microscopy for the same slice. This result indicated that reduced BMIPP uptake was caused by the myocardial fatty acid metabolic abnormality, not by the fibrosis in cardiomyopathy. Thus, FXCT images might be used to assess the quantitative metabolic analysis in small animal models of heart diseases.
Journal of Synchrotron Radiation 02/2007; 14(Pt 1):158-62. · 2.73 Impact Factor
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ABSTRACT: We tried to evaluate the blood flow in left ventricle quantitatively by combining wall thickness obtained from cardiac magnetic
resonance imaging (MRI) and myocardial perfusion from single-photon emission tomography (SPECT). Paired MRI and myocardial
perfusion SPECT from 16 patients including apical hypertrophic cardiomyopathy (APH) and normal subjects were considered. Blood
flow per unit myocardium volume was calculated by 3-D surface-based registration between MRI and SPECT images.
Evaluation was performed by creating bull’s eyes map of wall thickness, blood flow (cardiac perfusion), and blood flow per
unit myocardium volume. In APH case, decrease of the blood flow was detected in the cardiac apex by integration of the two
values though that could not be recognized from SPECT image alone.
Myocardium perfusion in left ventricle can be evaluated accurately by converting to the value per unit myocardium volume reflecting
wall thickness. And it helps to distinguish APH case whose SPECT image is resemble to a distribution of normal case.
12/2006: pages 2464-2467;
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ABSTRACT: In myocardial SPECT imaging with the popularly used 99mTc-sestamibi and 99mTc-tetrofosmin, intense liver uptake leads to a paradoxical decrease of counts in the absence of perfusion abnormalities, making it difficult to assess myocardial perfusion, particularly in the inferior or inferoapical left ventricular wall. 99mTc-N-DBODC5, which is a new lipophilic, mono-cationic nitride myocardial perfusion imaging agent, exhibits high myocardial uptake and excellent bio-distribution kinetics with rapid liver clearance in rats and dogs. 99mTc-N-DBODC5 myocardial imaging during vasodilator stress can determine the severity of stenosis, though underestimates occur with mild coronary stenosis compared to 201Tl, in a similar way to what occurs with 99mTc-sestamibi and 99mTc-tetrofosmin. In particular, 99mTc-N-DBODC5's rapid liver clearance, which may significantly reduce the photon scatter from the liver, allows for the reduction of artifactual decreased myocardial perfusion and the improvement of the diagnostic accuracy of coronary artery disease.
Recent Patents on Cardiovascular Drug Discovery 07/2006; 1(2):161-6.
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ABSTRACT: Fluorescent X-ray CT (FXCT), which has high-contrast and high-spatial resolution, is being developed for in-vivo biomedical research. Since FXCT could depict the specific heavy atomic number elements in the order of picogram, the functional imaging resembling to single photon emission CT can be obtained. We have applied this technique for in-vivo and ex-vivo biomedical imaging. FXCT system consists of a silicon (111) double crystal monochromator, an x-ray slit system, a scanning table for object positioning, fluorescent x-ray detectors, and pin-diode detectors. Using non-radioactive iodine labeled IMP, cerebral perfusion of a live mouse was clearly demonstrated at a 1 mm spatial resolution and a 0.1 mm slice thickness. In addition, the structure of extracted mouse brain fixed by formalin was depicted much clearly at 0.5 mm spatial resolution due to the availability of long data acquisition time. Thus, the success of in-vivo FXCT imaging with high resolution allows starting to new approach of bio-imaging research.
Image Processing, 2005. ICIP 2005. IEEE International Conference on; 10/2005
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ABSTRACT: To broaden the scope of phase-contrast X-ray imaging in biomedical applications, the energy of X-rays in a large-area imaging system using a two-crystal X-ray interferometer has been increased from 17.7 keV to 35 keV. The use of higher-energy X-rays makes it possible to observe larger samples having greater variation in density within shorter measurement periods, at higher spatial resolution, and at lower X-ray doses. After optimizing the imaging system for 35 keV X-rays, a 25 mm x 30 mm interference pattern with 50% visibility was generated at the Photon Factory. The system's capabilities are demonstrated by this pattern and a high-quality three-dimensional image of a rat heart.
Journal of Synchrotron Radiation 08/2005; 12(Pt 4):534-6. · 2.73 Impact Factor
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ABSTRACT: Coherence-contrast x-ray imaging--which detects changes in the degree of coherence caused by the placement of a sample in an x-ray interferometer--was developed for biomedical applications. Because the technique's sensitivity depends on the density gradient in the sample, it is particularly suitable for observing biomedical samples with large density differences, such as samples that include both biological soft tissue and bone. A measurement principle and method of this technique are described, and a fine coherence-contrast image of a mouse leg is given as an example result.
Applied Optics 07/2005; 44(16):3258-61. · 1.41 Impact Factor
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ABSTRACT: Gallium-67 citrate (67Ga) scintigraphy has been used as an indicator of activity of diffuse interstitial lung diseases. However, little has been mentioned in pulmonary alveolar proteinosis (PAP). Here we present a 53-year-old man with PAP showing patchy 67Ga uptake by single photon emission computed tomography (SPECT). Interestingly, the strong 67Ga uptake was observed in areas where ground-glass opacities were faint on chest CT. The uptake persisted after whole-lung lavage while the ground-glass opacity improved markedly. Although the precise mechanism of 67Ga uptake remains unclear, 67Ga SPECT findings may reflect the different pathological condition of PAP than that shown by CT.
Annals of Nuclear Medicine 03/2005; 19(1):47-50. · 1.50 Impact Factor
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01/2005
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ABSTRACT: Enhanced washout of 99mTc-tetrofosmin (TF) has been reported in patients with hypertrophic cardiomyopathy (HCM). Here, using quantitative dual-autoradiography, the relationship between TF retention abnormality and metabolism depicted by 125I-BMIPP uptake was investigated quantitatively in a hamster model of cardiomyopathy.
Early and delayed TF images were obtained at 5 min (7 cardiomyopathic and 5 normal hamsters) and 60 min (8 cardiomyopathic and 5 normal hamsters) after injection, respectively. BMIPP image was obtained 5 min after injection. Five cardiomyopathic and 5 normal hamsters were evaluated histologically. Percent uptake of TF and BMIPP in the heart was measured by an auto-well counter. The left ventricular wall was divided into 12 segments, and the relative regional uptake of TF and BMIPP was measured for each segment. Heterogeneity of radioactive distribution was determined by the standard deviation (SD) of radioactive counts in the left ventricular wall on autoradiogram. The uptake of early TF, delayed TF, and BMIPP in cardiomyopathic hamsters was 8.8%, 20.3%, and 25.3% lower than that in normal hamsters, p < 0.05, p < 0.01, and p < 0.001, respectively. In normal hamsters, distribution of radioactivity in all images was homogeneous, and the SD values were about 13. In cardiomyopathic hamsters, heterogeneous distribution was observed on all images, and the degree of heterogeneity was marked on delayed TF and BMIPP images. The SD was 19.7 +/- 1.2 for early TF image, 25.5 +/- 1.4 for delayed TF image, and 31.7 +/- 2.4 for BMIPP image, respectively. A weak linear correlation was observed between the relative regional uptake of the delayed TF and BMIPP in cardiomyopathic hamsters (r = 0.57). Electron microscopy demonstrated ultra-structural changes in mitochondria of cardiomyopathic hamsters.
Degree of retention abnormality on delayed TF image corresponded to the metabolic abnormality, probably due to mitochondrial dysfunction, depicted on BMIPP imaging.
Annals of Nuclear Medicine 05/2004; 18(3):195-202. · 1.50 Impact Factor
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ABSTRACT: Introduction A Skew-symmetric two-crystal X-ray interferometer (STXI, Fig. 1) is the most well-suited device for phase-contrast X-ray biomedical imaging based on X-ray interferometry. The field of view can be doubled compared with that of monolithic X-ray interferometers, and thermal disturbance caused by heat from a sample can be suppressed by separating the distance between the crystal wafer and the sample. To date, various biological samples such as rat livers have been observed[1] by our 3rd imaging system using STXI[2]. In vivo observation of cancer implanted in a nude mouse was also carried out, and the inner structure of the cancer, such as blood vessels, were revealed without the use of a contrast agent[3]. Last autumn, the height of the incident X-ray beam at BL-14C1 was expanded from 30 mm to more than 60 mm by rebuilding the transport channel of BL-14 (see the chapter of experimental facilities in this volume Part 1). To use this wide X-ray beam for the imaging, we first tried to generate a large-area X-ray interference pattern by using our 3rd imaging system. Results and discussion Figure 2 shows an interference pattern obtained using 17.7-keV X-rays. The pattern size was 60-mm wide and 40-mm high, which was determined by the crystal wafer of STXI. The view area of the imaging detector was too small to obtain the entire pattern in one exposure; therefore the pattern was observed with four exposures (3 sec each). Visibility was in the range from 40 to 60%, with an average of 50%, which is sufficient for use in phase-contrast imaging. Since no object was placed in the beam path, the interference fringes observed in the figure were due to the lattice strain and/or deformation of STXI. Our next step will be to observe large biological samples such as rabbit livers using this wide beam. We also plan to carry out in vivo observation of the growth process of a cancer over a few days. To do this, we are developing a new imaging detector, which will enables us to detect interference patterns five times faster than the current imaging detector. This method of observation will allow the in vivo evaluation of the effects of drugs in the near future.
AIP Conference Proceedings Nucl. Instr. and Meth. A Jpn. J. Appl. Phys. 01/2004; 705(43):1299-1302.
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ABSTRACT: OBJECTIVE: Enhanced washout of 99mTc-tetrofosmin (TF) has been reported in patients with hypertrophic cardiomyopathy (HCM). Here, using quantitative dual-autoradiography, the relationship between TF retention abnormality and metabolism depicted by 125I-BMIPP uptake was investigated quantitatively in a hamster model of cardiomyopathy. METHODS AND
RESULTS: Early and delayed TF images were obtained at 5 min (7 cardiomyopathic and 5 normal hamsters) and 60 min (8 cardiomyopathic and 5 normal hamsters) after injection, respectively. BMIPP image was obtained 5 min after injection. Five cardiomyopathic and 5 normal hamsters were evaluated histologically. Percent uptake of TF and BMIPP in the heart was measured by an auto-well counter. The left ventricular wall was divided into 12 segments, and the relative regional uptake of TF and BMIPP was measured for each segment. Heterogeneity of radioactive distribution was determined by the standard deviation (SD) of radioactive counts in the left ventricular wall on autoradiogram. The uptake of early TF, delayed TF, and BMIPP in cardiomyopathic hamsters was 8.8%, 20.3%, and 25.3% lower than that in normal hamsters, p < 0.05, p < 0.01, and p < 0.001, respectively. In normal hamsters, distribution of radioactivity in all images was homogeneous, and the SD values were about 13. In cardiomyopathic hamsters, heterogeneous distribution was observed on all images, and the degree of heterogeneity was marked on delayed TF and BMIPP images. The SD was 19.7 +/- 1.2 for early TF image, 25.5 +/- 1.4 for delayed TF image, and 31.7 +/- 2.4 for BMIPP image, respectively. A weak linear correlation was observed between the relative regional uptake of the delayed TF and BMIPP in cardiomyopathic hamsters (r = 0.57). Electron microscopy demonstrated ultra-structural changes in mitochondria of cardiomyopathic hamsters.
CONCLUSION: Degree of retention abnormality on delayed TF image corresponded to the metabolic abnormality, probably due to mitochondrial dysfunction, depicted on BMIPP imaging.
Annals of Nuclear Medicine. 01/2004;
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ABSTRACT: The diagnostic value of technetium-99m tetrofosmin (TF) washout in hypertrophic cardiomyopathy (HCM) was examined by investigating its relation to the metabolic abnormality depicted by iodine-123 beta-methyl- p-iodophenylpentadecanoic acid (BMIPP) uptake and the left ventricular (LV) myocardial wall thickness as measured by magnetic resonance imaging (MRI). TF washout was evaluated in 31 patients with HCM and 23 normal control subjects using 30-min (early) and 3-h (delayed) TF single-photon emission tomography images. The LV myocardial wall was divided into 19 segments and the percentage TF washout, regional BMIPP uptake and LV wall thickness were measured in each segment. Mean TF washout in the patients with HCM was significantly faster than that in normal control subjects (23.7+/-5.7 vs 13.4+/-4.1, P<0.0001). In the patients with HCM, TF washout showed an excellent correlation with MRI wall thickness ( r=0.82, P<0.0001) and a good inverse correlation with regional BMIPP uptake ( r=-0.72, P<0.0001). In addition, a good linear correlation was observed between TF uptake and MRI wall thickness in the 19 regional segments. In conclusion, the degree of TF washout corresponds well with the severity of myocardial wall thickness and the degree of metabolic abnormality in patients with HCM. These results suggest that enhanced TF washout might provide additional clinical information regarding metabolic alterations in HCM.
European journal of nuclear medicine and molecular imaging 08/2003; 30(7):966-73. · 4.99 Impact Factor
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ABSTRACT: Phase-contrast x-ray imaging using an x-ray interferometer has great potential to reveal the structures inside soft tissues, because the sensitivity of this method to hydrogen, carbon, nitrogen, and oxygen is approximately 1000 times higher than that of the absorption-contrast x-ray method. Imaging of vessels is very important to understand the vascular distribution of organs and tumors, so the possibility of selective angiography based on phase contrast is examined with a physiological material composed of low-atomic-number elements.
Phase-contrast x-ray imaging was performed with a synchrotron x-ray source. Differences in refractive index, ddelta, of physiological saline, lactated Ringer's solution, 5% glucose, artificial blood such as pyridoxylated hemoglobin-polyoxyethylene conjugate, and perfluorotributylamine were measured. Because the ddelta of physiological saline has highest contrast, it was used for the phase-contrast x-ray imaging of vessel, and this was compared with absorption-contrast x-ray images. Vessels >0.03 mm in diameter of excised liver from rats and a rabbit were revealed clearly in phase-contrast x-ray imaging, whereas the vessel could not be revealed at all by the absorption-contrast x-ray image. Absorption-contrast x-ray images with iodine microspheres depicted only portal veins >0.1 mm in diameter with nearly the same x-ray dose as the present phase-contrast x-ray imaging.
Phase-contrast x-ray imaging explored clear depiction of the vessels using physiological saline with small doses of x-rays.
Circulation 04/2002; 105(14):1708-12. · 14.74 Impact Factor
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Tohoru Takeda,
Akio Yoneyama,
Atsushi Momose,
Jin Wu,
Tsutomu Zeniya, Thet-Thet Lwin,
Yoshinori Tsuchiya,
Donepudi V Rao,
Kazuyuki Hyodo,
Keiichi Hirano,
Yuji Aiyoshi,
Yuji Itai
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ABSTRACT: Phase-contrast x-ray imaging with x-ray interferometer can depict the minute difference within the biological object, and its sensitivity is about 1000 times higher than that of absorption-contrast method. For biomedical use of this technique, a large monolithic x-ray interferometer and 2 crystal interferometer having a field of view with 25 mm x 25 mm is being developed. Phase-contrast x-ray CT could reveal detail structures within tumor and surrounded tissue, and the vessel imaging of rat liver is also possible using physiological saline at 17.7 keV x-ray energy. Recently, human breast tissues were imaged at 35 keV and the contrast of image was much better than usual absorption contrast x-ray image obtained at 17.7 keV energy.
Igaku butsuri: Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics: an official journal of Japan Society of Medical Physics 02/2002; 22(1):30-7.
