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Objective: In 2017, the Medical Accident Investigation and Support center in Japan released an analysis of acute pulmonary thromboembolism (PTE) related mortality. This recommendation called for maintaining a "team in charge of PTE's risk assessment, prevention, diagnosis and treatment" and preventing PTE through team activities. Therefore, we recommended establishing a deep vein thrombosis (DVT) prevention team. Before this recommendation, a multidisciplinary DVT prevention team was established in our hospital, with excellent outcomes. In the current study, we report the results of the DVT prevention team. Methods: Our multidisciplinary team consisted of several departments: Cardiovascular Surgery, ward nurses, medical safety managers, and clerks. The following themes were launched: 1) preparation of DVT prevention protocol; 2) preparation of DVT preventive manual; 3) regular round for evaluating DVT preventive measures; 4) staff education. The protocol's strong point was that nurses evaluated patients over 16-year-old with Wells' score for DVT on admission. We retrospectively investigated the diagnosis rate of DVT and PTE for 9 months before and after protocol operation. Results: The diagnosis rate of DVT was significantly improved after protocol implementation (before: 0.06% vs. after: 0.56%, p=0.0017). However, no significant difference was observed in the diagnosis rate of PTE before and after the protocol execution (before: 0.03% vs. after: 0.07%, p=0.98). Conclusion: Our DVT prophylactic protocol improved the diagnostic rate of DVT resulting in a decrease of PTE in our hospital. (This is a translation of Jpn J Phlebol 2019; 30(3): 285-293.).

The purpose of this study was to determine the effect of a synthetic tryptophan metabolite, tranilast [N-(3,4-dimethoxycinnamoyl)-anthranilic acid], on inflammatory and hemorrhagic areas after pulmonary radiofrequency ablation (RFA) in rabbits.Percutaneous RFA using a 17-gauge LeVeen electrode was performed in normal rabbit lungs. The rabbits were divided into tranilast-treated (300 mg/kg/day, orally) and control groups (n = 24/group). The effects of tranilast were evaluated using multidetector-row computed tomography (CT), histology, and immunohistochemistry immediately after RFA on days 1, 7, 14, and 28.Oral administration of tranilast significantly reduced the size of ablated lesions assessed using CT and histology on days 7 and 14. Furthermore, it reduced the hemorrhagic areas on day 7 and inflammatory areas on day 14, but did not affect the areas of coagulation necrosis on days 1, 7, 14, and 28. Immunohistochemical analysis showed an increase in the ratio of CD163-positive macrophage areas to rabbit macrophage (RAM11)-positive pan-macrophage areas and a decrease in the number of nuclear factor-κB-positive nuclei and CD31-positive microvessels in the tranilast group on days 7 and/or 14.The results suggest that tranilast modulates the repair process after pulmonary RFA through macrophage accumulation, suppression of inflammation, and angiogenesis.

This study aimed at demonstrating the feasibility of retrospectively fused (18)F FDG-PET and MRI (PET/MRI fusion image) in diagnosing pancreatic tumor, in particular differentiating malignant tumor from benign lesions. In addition, we evaluated additional findings characterizing pancreatic lesions by FDG-PET/MRI fusion image.We analyzed retrospectively 119 patients: 96 cancers and 23 benign lesions. FDG-PET/MRI fusion images (PET/T1 WI or PET/T2WI) were made by dedicated software using 1.5 Tesla (T) MRI image and FDG-PET images. These images were interpreted by two well-trained radiologists without knowledge of clinical information and compared with FDG-PET/CT images. We compared the differential diagnostic capability between PET/CT and FDG-PET/MRI fusion image. In addition, we evaluated additional findings such as tumor structure and tumor invasion.FDG-PET/MRI fusion image significantly improved accuracy compared with that of PET/CT (96.6 vs. 86.6 %). As additional finding, dilatation of main pancreatic duct was noted in 65.9 % of solid types and in 22.6 % of cystic types, on PET/MRI-T2 fusion image. Similarly, encasement of adjacent vessels was noted in 43.1 % of solid types and in 6.5 % of cystic types. Particularly in cystic types, intra-tumor structures such as mural nodule (35.4 %) or intra-cystic septum (74.2 %) were detected additionally. Besides, PET/MRI-T2 fusion image could detect extra benign cystic lesions (9.1 % in solid type and 9.7 % in cystic type) that were not noted by PET/CT.In diagnosing pancreatic lesions, FDG-PET/MRI fusion image was useful in differentiating pancreatic cancer from benign lesions. Furthermore, it was helpful in evaluating relationship between lesions and surrounding tissues as well as in detecting extra benign cysts.

To determine cellular viability of lung parenchyma and neoplastic cells in areas of ground-glass opacity (GGO) on computed tomography (CT) images immediately after pulmonary radiofrequency ablation (RFA) in rabbits.A LeVeen RFA electrode was placed percutaneously into rabbit lungs with or without metastatic VX2 tumors. Five minutes later, seven isolated lungs were imaged by use of a multi-detector row CT scanner, and the images were compared with histological features. The cellular viability of the lung tissues was assessed by nicotinamide adenine dinucleotide hydrogen (NADH) staining in eight normal lungs and in three lungs with multiple metastatic tumors.All lung lesions appeared as bilayered structures with a central, dense, attenuated area and an outer area of GGO on CT images, and as three-layered structures on macroscopic and microscopic images 5 min after RFA. The GGO areas approximately corresponded to the outer two layers in macroscopic images that were exudative and congestive on microscopic images. Staining for NADH was significantly reduced in the GGO and densely attenuated areas with or without tumor tissue staining compared with the non-ablated area.Our results suggest that an area of GGO that appears on CT immediately after RFA can be effectively treated by RFA.

The aim is to compare and evaluate the agreement of quantification of left ventricular functional parameters obtained by two different methods, (99m)Tc-tetrofosmin gated myocardial perfusion SPECT (MPS) and cardiac magnetic resonance imaging (CMR).Ten healthy male volunteers participated. Gated MPS data were acquired using 32 frames, which were also combined into 16- and 8-frame data set for the investigation. Gated CMR data were acquired using 8, 16 and 32-frame for the different sets. All examinations were conducted in resting and at exercise conditions. Quantitative measurements of end-diastolic volume (EDV), end-systolic volume (ESV), left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR) and time to peak filling (TTPF) were done for each study, respectively. Finally, we evaluated the concordance of parameters between gated MPS and gated CMR by % difference and Bland-Altman plot analysis.LVEF showed favorable concordance in both rest and exercise conditions (% differences were around 10%). PER, PFR and TTPF also showed good concordances in rest conditions, under 32-frame gated collections particularly (% differences were around 10%). In exercise conditions, although the concordances were relatively good, certain variances were noted (% differences were around 20-25%). Regarding left ventricular volumes, the concordance were worse in both conditions (% differences were around 30-40%).In quantifying of left ventricular function parameter, gated CMR provides similar quantitative values comparing with gated MPS except for ventricular volumes in rest conditions. In contrast, there were certain variations except for LVEF in exercised examinations. When we follow patients by the same cardiac parameters with CMR and MPS, using parameters across the two modalities proved to be possible under rest condition. However, it is limited at exercise condition.

Venous thrombus is subsequently organized and replaced by fibrous connective tissue. However, the sequential changes in venous thrombi are not reliably detected by current noninvasive diagnostic techniques. The purpose of this study is to reveal whether magnetic resonance (MR) can detect venous thrombus, define thrombus age and predict thrombolytic responses. Thrombus in the rabbit jugular vein was imaged with a 1.5-T MR system at 4 h and at 1, 2 and 4 weeks using three-dimensional (3D) fast asymmetric spin echo T2-weighted (T2W) and 3D-gradient echo T1-weighted (T1W) sequences. The jugular veins were histologically assessed at each time point. Magnetic resonance imaging (MRI) was also performed in vivo before and 30 min after tissue plasminogen activator (t-PA) administration. The thrombi in MRI were comparable in size to histological sections. The signal intensity (SI) of thrombi at 4 h was heterogeneously high or low on T2W or T1W images, respectively. The SI of thrombi on T2W images decreased time-dependently, but increased on T1W images at 1 and 2 weeks. Morphological analysis showed time-dependent decreases in erythrocyte, platelet and fibrin areas and time-dependent increases in smooth muscle cell, macrophage, collagen and iron areas. The t-PA administration significantly decreased thrombus volume at 4 h but not at 1, 2 and 4 weeks. Venous thrombosis can be reliably and noninvasively detected by MRI. Measurement of SI might support assessments of thrombus age and thrombolytic response.

Purpose The first aim of this study was to compare the detectability of metastasis of postoperative differentiated thyroid cancer (DTC) among 131I whole body scintigraphy (IWBS), fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), and diffusion-weighted magnetic resonance imaging (DWI). The second aim was to clarify the association between the image pattern and prognosis.

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Summary. Background: Plaque erosion is a cause of atherothrombosis that preferentially occurs on smooth muscle cell (SMC)- and proteoglycan-rich rather than lipid-rich plaques. However, its underlying mechanisms remain unknown. Objective: To determine whether disturbed blood flow induces erosive injury and thrombus formation on SMC-rich neointima. Methods: Three weeks after balloon injury, SMC-rich neointima with increased tissue factor (TF) activity developed in rabbit femoral arteries that were narrowed with a vascular occluder to disturb blood flow after stenosis. Neointimal injury and thrombus formation were assessed at 15, 30, and 180 min after the vascular narrowing. Results: Endothelial detachment, platelet adhesion and neointimal cell apoptosis became evident at the post-stenotic regions of all femoral arteries (n = 5) within 15 min of narrowing. Mural thrombi composed of platelet and fibrin developed after 30 min, and then occlusive thrombi were generated in three out of five vessels after 180 min. The identical vascular narrowing of normal femoral arteries also induced endothelial detachment with small platelet thrombi at post-stenotic regions, but fibrin and occlusive thrombi did not develop. Computational simulation analysis indicated that oscillatory shear stress contributes to the development of erosive damage to the neointima. Conclusions: These results suggest that disturbed post-stenotic blood flow can induce erosive injury in SMC-rich plaques and promote thrombus formation that results in vascular events.

The deep-inspiration breath-hold PET/CT (DIBH PET/CT) technique improves the limitations of diagnosing a lesion located in an area influenced by respiratory motion that results in spatial misregistrations caused by respiration between PET and CT. However, its reproducibility with regard to calculating the maximal standardized uptake value (SUV(max)) and metabolic volume (MV) in DIBH PET/CT has not been elucidated.The purpose of this study was to investigate the reproducibility of the DIBH PET/CT technique including calculating the SUV(max) and the MV.Sixty patients with various cancers were enrolled. The subjects had 47 abdominal lesions and 28 chest lesions. All patients demonstrated a misregistered image in the early whole-body image taken 50 min after FDG intravenous infusions. We added the delayed spot images 40 min after the first image. On the delayed image, we performed both conventional techniques with non-breath-hold (NBH) and the DIBH technique. In the four times DIBH technique, we obtained the coefficient of variance (CV) in calculating these indices for evaluating reproducibility.The SUV(max) value with DIBH showed an increase of 16.1-60.1% compared with that measured by NBH. The mean value of CV was 5.5 in thoracic lesions and 6.3 in abdominal lesions. The values of MV with DIBH showed a decrease of 14.0-20.1% compared with those measured by NBH. Regarding reproducibility, mean value of CV was 7.1 in thoracic lesions and 11.9 in abdominal lesions.The DIBH technique improves the inaccurate quantification of both SUV(max) and MV. Although the CV value of SUV(max) with DIBH technique is better in thoracic lesions compared with that in abdominal lesions, the reproducibility was acceptable.

Rationale and Objectives Atherothrombosis usually occurs on macrophage- and lipid-rich unstable plaque, but rarely on smooth muscle cell (SMC)-rich stable plaque. Magnetic resonance imaging (MRI) has been extensively applied for noninvasive vascular imaging. We therefore investigated whether MRI provides valuable information about the characteristics of atherosclerotic vessels using rabbit models of macrophage-rich or SMC-rich atherosclerotic arteries. Materials and Methods Rabbits were fed with a conventional (CD group, n = 3) or 0.5% cholesterol (ChD group, n = 3) diet for 1 week before and 3 weeks after balloon injury of the left iliac arteries. Three weeks later, these arteries were investigates by 1.5 T MRI and by conventional angiographic imaging, followed by histological and immunohistochemical analyses. Results Three weeks after balloon injury, injured iliac arteries of both groups formed neointima with luminal stenosis. Conventional and MRI angiographic findings of the luminal diameter significantly and positively correlated. T1 relaxation time was significantly shorter and the lipid content was much higher in injured arteries from the ChD than from the CD group. The injured arteries from the ChD also contained more macrophages and less SMCs that those from the CD group. The T1 relaxation time and lipid content in injured arteries negatively and positively correlated with the degree of macrophage accumulation, respectively. Conclusion These results showed that MRI could provide valuable information about luminal stenosis and the characteristics of atherosclerotic vessels in rabbits.

Introduction Thrombus growth under low blood flow velocity plays an important role in the development of deep venous thrombosis (DVT). Increased plasma levels and activities of coagulation factor VIII (FVIII) comprise risk factors for DVT and pulmonary thromboembolism. Objective To localize FVIII in human venous thrombi of DVT and to determine whether FVIII contributes to thrombus formation under low shear conditions. Methods The localization of FVIII in venous thrombi obtained from patients with DVT was examined by immunohistochemistry. The role of FVIII in thrombus formation was investigated using a flow chamber system. Venous blood from healthy volunteers were incubated with an anti-FVIII monoclonal antibody (VIII-3776) or non-immunized mouse IgG1. Blood samples were perfused on immobilized type III collagen at wall shear rates of 70/s and 400/s and then the surface area covered by platelets and fibrin was morphometrically evaluated. Prothrombin fragment 1+2 (PF1+2) generation was measured before and after perfusion. Results Venous thrombi of DVT comprised a mixture of platelets, fibrin and erythrocytes. Factor VIII appeared to be colocalized with glycoprotein IIb/IIIa, fibrin and von Willebrand factor in the thrombi. VIII-3776 specifically recognized the light chain of FVIII and prolonged the activated partial thromboplastin time (aPTT), but not prothrombin time (PT). The antibody significantly reduced platelets and fibrin covering, as well as PF1+2 generation at wall shear rates of 70/s and 400/s. Conclusions These results suggest that FVIII contributes to platelet aggregation and fibrin formation via thrombin generation under low shear conditions.

Resume Objectif Rechercher l’apport de l’imagerie par resonance magnetique (IRM) nucleaire pour la detection des metastases tumorales touchant la jonction discovertebrale (JDV) sur des echantillons cadaveriques et chez des patients. Comparaison avec les donnees histologiques. Methodes Trente JDV provenant de dix cadavres presentant des metastases osseuses averees ont ete etudiees a l’IRM. Des coupes anatomiques et des evaluations histologiques ont ete pratiquees ; les coupes anatomiques ont ensuite ete confrontees aux images d’IRM. Pour l’etude clinique, l’IRM de trois patients presentant des metastases vertebrales a ete relue. Resultats A l’IRM, l’intensite du signal des metastases du corps vertebral etait variable. Cet examen n’a pas permis de detecter les foyers de metastases envahissant les plaques cartilagineuses. L’examen histologique a retrouve une infiltration de la JDV par du tissu tumoral chez 11 (69 %) des 16 JDV avec contour irregulier et pour cinq (31 %) des JDV interrompues. Chez trois cadavres et chez trois patients, l’examen histologique a montre une metastase du disque intervertebral. Dans aucun prelevement, l’IRM n’a permis de montrer un envahissement tumoral du disque. Conclusions Nos resultats permettent de soutenir la notion que les metastases tumorales peuvent envahir la plaque cartilagineuse, par l’intermediaire d’une degradation de ses constituants, permettant ainsi un contact direct entre la tumeur et le disque. Il est possible que l’IRM ou l’examen macroscopique, voire les deux a la fois, echouent a detecter un envahissement tumoral minime de la JDV car les images des petits foyers de metastases peuvent etre masquees par les anomalies de morphologie de la plaque cartilagineuse vertebrale.

The conventional delayed scan in dual phase of thallium-201 ((201)Tl) single-photon emission computed tomography (SPECT) is useful for estimating the viability of non-small-cell lung cancer (NSCLC). However, the influence of tumor blood flow cannot be ignored by the scan at 4 h after the tracer injection. For the purpose of improving the diagnostic capability and for clarifying the association between (201)Tl uptake and proliferative activity, we investigated the usefulness of super-delayed scan obtained at 24 h in triple-phase (201)Tl SPECT.A total of 122 patients with lung nodule, 106 of NSCLC and 16 of benign nodule, were given (201)Tl SPECT before the tumor resection. Early image (15 min), delayed image (4 h), and super-delayed image (24 h) were obtained after intravenous injection of (201)Tl chloride (111 MBq). On the each SPECT image, regions of interest (ROIs) were placed over the tumor contour (T) and contra-lateral normal lung tissue (N) area on one transverse view clearly defined lesions, and T/N ratio on the early image (ER), the delayed image (DR), and the super-delayed image (sDR), and retention indexes (RI and sRI) were calculated. All patients underwent subsequent surgical excision, and the specimens were immunostained for Ki-67 and CD34. The proliferative capability was measured as a percentage of positive nuclear area for Ki-67 (MIB-1 index). The angiogenesis was measured density of positive micro-vessels for CD34 (micro-vessel density, MVD). Correlation analysis was performed to evaluate the relationship between the MIB-1 index, MVD, and SPECT parameters.The diagnostic accuracy of sDR in the differential of NSCLC was higher than that of DR (83.6% vs. 91.8%). Both DR and sDR were positively correlated with MIB-1 index. The correlation coefficient was higher in sDR (0.53 vs. 0.69). The MIB-1 index of the increasing pattern (RIsRI) group was significantly higher (P0.001) than that of the decreasing pattern (RIsRI) group.The super-delayed scan in the triple-phase (201)Tl SPECT is more useful than conventional delayed scan for both the diagnostic capability and assessing proliferation of NSCLC.

Purpose Firstly, to assess the effect of percutaneous endoscopic gastrostomy (PEG) tube placement on gastric emptying, gastrointestinal (GI) tract motility and the rate of gastroesophageal reflux (GER). Secondly, to confirm whether correlations exist between drug absorption behaviour and GI tract motility using the combination method of absorption function analysis with the motility study. Methods Subjects comprised 11 patients with neurological dysphagia. Gastric-emptying scintigraphy was performed both before PEG via nasogastric tube feeding and after PEG placement. After fasting for more than 8 h, each patient was administered 111 MBq of 99mTc-labelled diethylenetriaminepentaacetic acid (DTPA) with a 100 ml liquid meal via a nutrition tube. Dynamic imaging was performed immediately after administration of a radiolabelled liquid meal for a 1 h period and static imaging was performed after 1, 2, 3 and 6 h. Gastric emptying half-time (T50) was calculated in each patient, and GER ratio and GI transit rate were also evaluated. Simultaneously, we administered 10 mg of famotidine in six of the 11 patients and measured serum concentrations of famotidine at 0, 1, 2, 3 and 6 h. Using the time-concentration curve of famotidine, the maximum concentration of famotidine (Cmax) and area under the curve of famotidine (AUCf) were calculated for each patient. Results In seven of 11 patients, T50 changed after PEG placement, but not significantly. The GER ratio was significantly decreased and complicated pneumonia improved after PEG placement. GI transit rate for each GI segment was unchanged after PEG placement. Significant linear correlations were identified between T50 and both Cmax and AUCf. Conclusion Gastric-emptying scintigraphy with Tc-DTPA was effective in the evaluation of GI transit before and after PEG, as well as in assessing GER. Motility and famotidine absorption were maintained after PEG placement. Significant linear correlations were found between T50 and both Cmax and AUCf. These findings suggest that drug absorption may have some relationship between T50. The result may be more reliable with a larger population.

PURPOSE To investigate whether 201Tl uptake is associated with cell proliferation and angiogenesis in non-small-cell lung carcinoma (NSCLC). METHODS Eighty-four patients with scheduled NSCLC underwent 201Tl single photon emission computed tomography (SPECT) imaging: 15 min (early scan) and 240 min (delayed scan) after intravenous injection of 111 MBq of 201Tl chloride. 201Tl indices were calculated on early images (early ratio: ER) and delayed images (delayed ratio: DR). The retention index (RI) was also calculated from these two parameters. Using surgically resected cancer specimens (54 adenocarcinoma, 24 squamous cell carcinoma (SCC), six large-cell carcinoma), immunohistochemical stains for both Ki-67 (MIB-1 index) and CD34 were performed to examine the proliferative activity and the micro-vessel density (MVD), respectively. RESULTS The mean value of 201Tl index was 1.69+/-0.77 (ER) and 2.31+/-1.08 (DR). The average RI was 42.6+/-42.9%, respectively. Both DR and RI positively correlated with MIB-1 index (r = 0.68, P < 0.05 and r = 0.52, P < 0.05). When we analyse adenocarcinoma and SCC separately, there was a significant positive correlation (r = 0.62, P < 0.05) between RI and MIB-1 index in adenocarcinoma but not in SCC (r = 0.20, P = NS). The value of ER positively correlated with MVD (r = 0.75, P < 0.05). It demonstrated strong positive correlation with both histological types (adenocarcinoma: r = 0.80, P < 0.05, SCC: r = 0.66, P < 0.05). CONCLUSION 201Tl SPECT imaging is effective non-invasive method for assessing both the proliferation and the angiogenesis in NSCLC. Both DR and RI are useful indicators for assessing cancer cell proliferation in lung adenocarcinoma. ER is a useful marker for assessing the tumour angiogenesis in NSCLC.

Paragonimiasis westermani, or Oriental lung fluke, is a common parasitic zoonosis, which is acquired from eating the flesh of wild boar or freshwater crabs. After being ingested by humans, the larvae of P. westermani migrate across small intestinal mucosa into the intra-abdominal space, and then finally into to the pleural space and lung parenchyma. High-resolution CT findings of P. westermani consist of worm cysts, migration track, peripheral density, bronchial wall thickening, and centrilobular nodules, which prompt serological tests and detection of eggs in sputum or BAL fluid for definitive diagnosis.

Objective The purpose of this study was to describe the normal anatomy and abnormalities of the lumbar intervertebral disk with sonography in cadaveric specimens and to correlate the sonographic findings with pathologic findings. Methods Sonographic imaging with both 4.5- and 10-MHz linear array transducers was performed on 35 lumbar intervertebral disks in 13 human cadaveric spines. The cadaveric specimens were sectioned for anatomic and histopathologic evaluation. Findings on anatomic sections were correlated with the findings on corresponding sonographic images with respect to the sonographic appearance of disk components in 30 intervertebral disks. Results High-resolution sonography with a 10-MHz frequency transducer enabled distinction of the nucleus pulposus from the annulus fibrosus and assessment of the echogenic characteristics of these structures. Sonography showed numerous fine linear echoes in the outer portion of the intervertebral disk in 26 (87%) of 30 specimens, which corresponded to the normal concentric arrangement of the fibers in the periphery of the annulus fibrosus. Amorphous areas of low echogenicity in the inner portion of the annulus fibrosus (n = 14, 47%) correlated with degenerative changes of the disk on corresponding microscopic sections. The nucleus pulposus appeared relatively isoechoic (n = 5, 17%) or hyperechoic (n = 4, 13%) to the annulus fibrosus. In degenerative disks (n = 21, 70%), the nucleus pulposus showed decreased echogenicity, and differentiation between the nucleus pulposus and annulus fibrosus was difficult. Conclusions High-resolution sonography is a simple imaging method that can show the normal lumbar intervertebral disk and degenerative changes in appropriate subjects. High-resolution sonography proves superior to conventional sonography for evaluation of the lumbar intervertebral disk.

Background—Platelet-rich thrombus formation is a critical event in the onset of cardiovascular disease. Because ADP plays a significant role in platelet aggregation, its metabolism is important in the regulation of platelet activation and recruitment. Ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) is a key enzyme involved in vascular ADP metabolism. We recently isolated 2 isoforms of E-NTPDase from the human placenta. The present study examined whether these isoforms suppress platelet aggregation and thrombus formation after adenovirus-mediated gene transfer to vascular smooth muscle cells (SMCs).Methods and Results—We constructed adenovirus vectors expressing human placental E-NTPDase isoforms I (AdPlac I) and II (AdPlac II) or bacterial β-galactosidase (AdLacZ). Vascular SMCs infected with AdPlac I expressed significant NTPDase activity and inhibited the platelet aggregation induced by ADP and collagen in vitro. In contrast, SMCs infected with AdPlac II and AdLacZ did not exert antiplatelet effects. To investigate the antithrombotic and antiproliferative effects of placental E-NTPDase isoform I in vivo, we generated thrombosis in rat carotid arteries by systemically administered rose Bengal and transluminal green light 5 days after gene transfer and examined neointimal growth 3 weeks after thrombus formation. Blood flow in AdLacZ-infected arteries rapidly deteriorated and vanished within 96±18 seconds of occlusive thrombus formation. In contrast, blood flow in AdPlac I–infected arteries was preserved for at least 10 minutes during irradiation. In addition, thrombus formation and subsequent neointimal growth were obviously suppressed.Conclusions—The local expression of placental E-NTPDase in injured arteries might prevent arterial thrombosis and subsequent neointimal growth.

Objective— Plaque disruption does not always result in complete thrombotic occlusion. The mechanism of arterial thrombus propagation remains unclear. Methods and Results— We studied how vascular wall thrombogenicity and blood flow reduction affect thrombus propagation using a rabbit model of single and repeated balloon injury. After balloon injury of the normal femoral artery, the blood flow was reduced to 50%, 25%, or 10% (n=5). Small mural thrombi composed of aggregated platelets were produced, but no occlusive thrombi developed in any flow reduction. Three weeks after the first balloon injury, neointima with tissue factor expression and increased procoagulant activity was developed. Balloon injury of the neointima with the same blood flow reduction (n=5) induced fibrin-rich thrombus formation. Additionally, injury with flow reduced to 25% and 10% promoted thrombus propagation resulting in vessel occlusion within 160±18 and 71±17 seconds, respectively. An injection of anti-von Willebrand factor (vWF) monoclonal antibody (AJW200; 1.0 mg/kg) prevented occlusive thrombus formation. Conclusions— Increased vascular wall thrombogenicity together with a substantial blood flow reduction is crucial for occlusive thrombus formation, and vWF plays an important role in thrombus propagation. Reduced blood flow at plaque disruption sites might contribute to thrombus propagation leading to acute coronary syndromes.

Objective— It has become clear that von Willebrand factor (vWF) plays important roles in platelet adhesion and aggregation under high blood-flow velocity conditions observed in stenotic atherosclerotic arteries. However, its roles in thrombus formation in vivo on diseased arteries have not been fully understood. We examined the contribution of vWF to thrombus formation and subsequent intimal growth by using a repeated balloon-injury model in rabbits. Methods and Results— Rabbit iliac arteries 4 weeks after a first balloon injury showed 37% luminal stenosis by neointimal growth, and blood velocity increased by 2.1 times compared with that of uninjured arteries. The second balloon injury induced fibrin-rich thrombus formation on the injured neointima. Intravenous administration of a monoclonal antibody against vWF (AJW200, 1.0 mg/kg body weight) remarkably prevented botrocetin-induced platelet aggregation ex vivo for 2 days; moreover, thrombus formation, cell proliferation, and subsequent neointimal growth were significantly reduced at 30 minutes, 5 days, and 4 weeks, respectively, after the second balloon injury. Conclusions— These results indicate that vWF plays a potent role in fibrin-rich thrombus formation on the neointima under high blood-flow velocity conditions. Inhibition of plasma vWF activity might be effective for the reduction of thrombus formation and/or subsequent neointimal development after coronary interventions.

The aim of this study was to develop a new artificial amino acid radiopharmaceutical labelled with radioiodine for detection of malignant melanoma, based on melanin formation. By considering the affinity for tyrosinase, a starting enzyme on the branching point to melanin biosynthesis, 3-[ 125 I]iodo-4-hydroxyphenyl-L-cysteine ( 125 I-L-PC) was synthesized and evaluated biologically. Labelling of 125 I-L-PC using the chloramine-T method was carried out conveniently and efficiently in a short period of time, with high specific activity. In a biodistribution study, 125 I-L-PC showed a low accumulation in normal tissue and relative retention in B16 melanoma. A high contrast image of peripheral tumour was obtained during autoradiography. During an in vitro accumulation study, inhibition of 125 I-L-PC with a tyrosinase inhibitor suggested interaction of this tracer with tyrosinase. It indicates that the uptake mechanism of 125 I-L-PC to melanoma tissue was dependent on high tyrosinase activity in melanoma cells. Thus, 125 I-L-PC appears to be a promising radioiodinated amino acid radiopharmaceutical for imaging malignant melanoma in relation to melanin formation, namely specific metabolism with high tyrosinase activity.

The current study was performed to investigate the influence of high temperature on the value of radiation dose measured by optically stimulated liminescence (OSL) dosimeter or radio photo luminescence (RPL) dosimeter (glass dosimeter) . Serial measurements of temperature in the car confirmed that it can rise to 80°C or higher in the area irradiated with sun beam. The relationship between the temperature and the radio dose measured by X-ray irradiated OSL dosimeter or glass dosimeter under the condition from 50°C to 90°C after the set of 3h. to 72h.The value measured by OSL dosimeter tended to be lower with higher temperature or longer setting time. On the other hand, those factors did not influence the value measured by glass dosimeter.

Radiation measurement with film badges is influenced by thermal energy and it is sometimes reported to be exposed to higher radiation by mistake under the condition with higher temperature. Because of no practical data regarding relationship between temperature and radiation dose, estimation of the true value under the condition with higher temperature was difficult. The current study was performed to clarify the influence of probable high-temperature on the radiation dosimetry by film badge system.Serial measurements of temperature in the car confirmed that it can rise to 80°C or higher in the area irradiated with sun beam. The setting time was ranged from 3h to 48h and the temperatures were monitored from 60°C to 110°C. Exposure dose was increased by the elevation of temperature. Significant correlation was confirmed between the temperature and the exposure dose measured by film badges. It was also confirmed that high temperature influenced the sensitivity of film badges.

rationale and objectives. To examine the correlation between the echogenicity and the components of atherosclerotic plaques in rabbit. methods. The atherosclerotic plaque formation in the abdominal aortas of hyperlipidemic or normolipidemic rabbits was stimulated by inserting polyethylene tubing. Intravascular ultrasound (30-MHz, 4.5 F catheter) investigation was performed at locations in the vessel. The intravascular ultrasound images of the plaques were evaluated and compared with the histologic findings. results. Ultrasound images delineated areas showing hyperechoic or hypoechoic ultrasound beams in the plaques. Histologic studies revealed that the hyperechoic areas were closely associated with a dense fibrous extracellular matrix, whereas the hypoechoic areas corresponded to lesions showing a marked accumulation of foamy macrophages or proteoglycan-rich loose myxoid extracellular matrix with smooth muscle cell proliferation. conclusion. A good correlation between ultrasound images and histologic features was observed. These results suggest that intravascular ultrasound imaging could provide useful information for assessing the tissue characteristics of atherosclerotic lesions.

The plasma concentration-time profile of theophylline after oral administration in human volunteers was predicted using the individual gastrointestinal (GI) transit data monitored by a gamma scintigraphic technique. Theophylline was administered as aminophylline under fasted and fed condition, along with 99mTc-labeled diethylenetriamine-pentaacetic acid (DTPA), an unabsorbable marker to evaluate the GI transit by a gamma scintigraphic technique. Two healthy male volunteers participated under fasted and fed conditions in a crossover study. The GI transit was evaluated by dividing the GI tract to four segments, stomach, jejunum, ileum and cecum/colon. Under the fed condition, the GI transit pattern for each segment was confirmed to alter considerably, causing a delay in the gastric emptying mainly. Further, the plasma concentration curves of theophylline after oral administration were predicted using the GI-Transit-Absorption Model on the basis of individual GI transit parameters calculated by the fitting of the observed data to the GI-Transit Kinetic Model. The absorption rate constant in each segment and the pharmacokinetic parameters after intravenous administration used for the prediction were the values extrapolated from the data in rats and the ones normalized from the values in literatures, respectively. The plasma concentration-time curves for theophylline were well predicted using obtained individual GI transit parameters. The analysis using this method could estimate the variable absorption behavior governed by the GI transit in detail.

Technetium-99m methoxy-isobutylisonitrile (MIBI), like thallium-201 (201Tl), is a highly efficient agent for the diagnosis and monitoring of glioma tumors. Although 201Tl uptake is known to be partly associated with proliferative activity, little is known about the correlation between MIBI uptake and proliferation activity in gliomas. The current study was performed to assess the correlation between MIBI uptake and proliferative activities in gliomas, estimated by the monoclonal antibody to Ki-67 antigen (MIB-1) staining method. By comparing the results with those of 201Tl, we determined which tracer would be suitable for estimating proliferative activities. Twenty-four presurgical glioma patients (six with low-grade gliomas, five with anaplastic astrocytomas, and 13 with glioblastomas) were given MIBI and 201Tl SPECT. Early (10 min after injection) and delayed images (3 h after injection) were obtained for both MIBI and 201Tl scintigraphy. SPECT parameters, early ratio (ER), delayed ratio (DR), and retention index (RI) were obtained in both radiopharmaceuticals. All patients underwent subsequent surgical excision, and the specimens were immunostained for MIB-1. The proliferative activity was measured as a percentage positive nuclear area for MIB-1 (MI; MIB-1 index). To evaluate the relationship between the proliferative activity and SPECT parameters, we performed a correlation analysis. MI correlated with the MIBI uptake ratio (r = 0.75 for ER, and r = 0.7 for DR). Both DR and RI of 201Tl also correlated with MI, but weakly (r = 0.6 for DR, and. r = 0.59 for RI). There was no significant correlation between the MIB-1 index and the other parameters. MIBI-uptake parameters demonstrated a stronger positive correlation with the MIB-1 index than that of 201Tl. With the use of MIBI SPECT, we can estimate the proliferative activity of glioma noninvasively.

We determined the effect of retention on the changes in regional biodistribution of Tc-99m ECD in the brain. A total of 14 cases, 7 normal volunteers and 7 patients with various diagnoses but with very minimal radiologic findings or none were included in the study. SPECT images were taken at 30 min, 1, 2, 3, 4 and 6 hrs after an intravenous injection. Retention rates were calculated in various regions and were corrected according to the time decay of technetium. There was a tendency for the retention rate to increase up to three hours of imaging and then a decrease was noted in most regions of the brain. In the thalamus, increasing retention was noted. In conclusion, Tc-99m ECD retention in the different regions of the brain varies with time. These differences should always be considered when planning and interpreting SPECT quantitative studies.

The 3D fast asymmetric spin echo (FASE) method combines the half-Fourier technique and 3D fast spin echo (FSE) sequence. The advantage of this method is that it maintains the same spatial resolution as FSE while markedly reducing the imaging time. The purpose of the present study was to evaluate the usefulness of the 3D FASE technique in displaying the inner ear structure using phantom and volunteer studies. 3D FSE sequence images were obtained for comparison, and the optimum 3D FASE sequence was investigated on a 1.5T MR scanner. The results of phantom experiments showed increased signal-to-noise ratio (SNR) with prolonging repetition time (TR) on both 3D FASE and 3D FSE sequences. Although the SNR of 3D FASE images was 20–25% lower than that of 3D FSE images with the same TR, the SNR per minute with 3D FASE was about twice that with 3D FSE. On 3D FASE images, a higher spatial resolution was obtained with 2- or 4-shot images than with single-shot images. However, no significant difference was observed between 2-shot and 4-shot images. In the volunteer study, 3D FASE images using a TR of 5000 ms and an effective echo time (TE eff ) of 250 ms showed a high SNR and spatial resolution and provided excellent contrast between cerebrospinal fluid and nerves in the internal auditory canal. The highest contrast was achieved in the 2-shot/2 number of excitations sequence. 3D FASE provides the same image quality as 3D FSE with a significant reducing in imaging time, and gives strong T2-weighted images. This method enables detailed visualization of the tiny structures of the inner ear.

The case of a 77-year-old male patient who complained of left upper quadrant pain and progressive vomiting. Laboratory examination showed extremely high lactic acid dehydrogenase (LDH) and adult T-cell leukemia antibody (ATLA). The anatomical studies CT, MRI, US and upper GI series substantiated an omental lymphadenopathy which was causing a circumferential compression of portions of the duodenum and jejunum. Gallium-67 citrate (Ga-67) scintigraphy showed high uptake at LUQ. Ultrasound guided biopsy failed to confirm the diagnosis. Irradiation was performed. Ga-67 scintigraphy had a contributory role in clinical subtyping of the disease, planning of treatment, posttreatment assessment and prognostication of adult T-cell lymphoma.

Open image in new window What is the definition of CIN? Answer: CIN is defined as an increase in serum creatinine (SCr) levels by ≥0.5 mg/dL or ≥25 % from baseline within 72 h after a contrast radiography using iodinated contrast media. Open image in new window Because the risk for developing CIN increases as kidney function decreases, it is important to evaluate kidney function on the basis of the latest SCr levels prior to contrast radiography. According to the classification of the severity of CKD, which is based on the cause, GFR, and presence and severity of albuminuria (Table 1) [1], patients with a GFR of

Although positron emission tomography (PET) using [18F]-fluoro-2-deoxy-d-glucose (18F-FDG) is established as one of the first-choice imaging modalities in the diagnosis of chest malignancies, there are several problems to solve in clinical practice, such as false positive uptake in inflammatory diseases. The aim of this study was to evaluate the clinical usefulness of an amino acid tracer, α-[N-methyl-11C]-methylaminoisobutyric acid (11C-MeAIB), in the diagnosis of chest malignancies, in combination with 18F-FDG. Fifty-nine cases (57 patients, 66 ± 12 years old) who consulted to our institution for the wish to receive differential diagnosis of chest diseases were included. Purpose of the studies were as follows: differential diagnosis of newly developed lung nodules, n = 22; newly developed mediastinal lesions, n = 20; and both, n = 17 (including lung cancer: n = 19, lymphoma: n = 1, other cancers: n = 2, sarcoidosis: n = 15, non-specific inflammation: n = 18, other inflammatory: n = 4, respectively). Whole-body static PET or PET/CT scan was performed 20 and 50 min after the IV injection of 11C-MeAIB and 18F-FDG, respectively. 11C-MeAIB uptake of malignant and benign lesions was statistically different both in pulmonary nodules (p

Minute pulmonary meningothelial-like nodules (MPMNs), previously known as minute pulmonary chemodectomas, are relatively rare lesions. They are small (1-3 mm) and often multiple. Pathologically, they represent an interstitial nodular proliferation of small oval or spindle-shape cells arranged in a "zellenballen" nesting pattern. The function and origin of the cells are unknown. These nodules are associated with specific conditions, including thromboembolism, cardiac disease, and malignancy. We describe a patient with MPMNs and adenocarcinoma of the lung in whom HRCT showed tiny (1-3 mm in diameter) nodules of ground-glass attenuation.

If a contrast-enhanced examination using an iodinated contrast medium is to be performed, a questionnaire is commonly used to understand the patient’s condition to assess the risks associated with the use of the contrast medium. However, there is much uncertainty about evidence from questionnaires, and it is left to each medical institution to determine the questions and how patients should be asked. The Japan Radiological Society/Japanese College of Radiology Joint Committee on Contrast Media Safety (hereafter referred to as “this Committee”) listed and sorted the questions frequently asked in questionnaires on iodinated contrast media and determined whether there is literature to support each question. In addition, for Japanese package inserts for iodinated contrast media, this Committee sought to present the recommended questions prior to the use of iodinated contrast media with their grades of recommendation, using criteria that were as objective as possible. Received: April 21, 2011 / Accepted: May 27, 2011 © Japan Radiological Society 2011

The current study was done to evaluate the usefulness of predicting capability of FDG PET/CT indices in therapeutic response of malignant tumor.Series of FDG PET/CT were performed at both pre- and after therapy for 70 lesions of 58 patients with malignant tumor. Three months after the 2nd PET/CT, follow up CT was performed for determining the final therapeutic effect. We calculated various indices including SUVmax, the metabolic volume (MV) and the total lesion glycolysis (TLG). We calculated four kinds of indices, TLG50, TLG75, MV50 and MV75 based on the different threshold. Then we calculated deltaSUVmax, deltaMV50, deltaMV75, deltaTLG50 and deltaTLG75 from a change of these indices. Finally, we compared the predictive capability of these five indices in therapeutic response of malignant tumor.In the cancer therapy effect prediction, both deltaTLG75 and deltaTLG50 were significantly higher than SUVmax by using receiver operating-characteristic (ROC) curve analysis. The prognostic capability of deltaSUVmax for therapeutic response with sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 85.7%, 59.5%, 58.5%, 86.2% and 70.0%; deltaTLG75 96.4%, 69.0%, 67.5%, 96.7% and 80.0%; and deltaTLG50 96.4%, 76.2%, 73.0%, 97.0% and 84.3%, respectively. By the use of deltaTLG75 or deltaTLG50, the predictive ability for therapeutic response improved significantly compared to that by the use of deltaSUVmax.In the prediction for therapeutic response of various cancers by using FDG PET/CT, Total lesion glycolysis (TLG) was the most useful index.

Complete deficiency of hypoxanthine guanine phosphoribosyltransferase (HPRT) causes Lesch-Nyhan syndrome. A single nucleotide substitution of G to T at the 3'-end of intron 3 in the splicing consensus region has been identified in one allele of the HPRT gene from a mother predicted to be a heterozygous Lesch-Nyhan carrier. Utilizing a BfaI restriction site which was lost in the mutation as an indicator, family study showed that the mother and her only daughter were heterozygotes but the mother's sister did not have the mutant allele. The mutation generated splicing error and resulted in two types of abnormal mRNA. The major altered mRNA, named Type I, skipped the exon 4 and is predicted to produce a protein deleted of 22 amino acid residues. The other, Type II, having a 9-bp deletion at the 5'-end of exon 4, can result in a protein lacking 3 amino acids, from codon 107 to 109.

OBJECTIVE The aim of our study was to ascertain the optimal timing and scanning method for detecting hepatocellular carcinoma (HCC) as a high density mass during the early phase of dynamic hepatic CT and to confirm its clinical effectiveness. MATERIALS AND METHODS We studied retrospectively 39 patients with clinically diagnosed HCC who underwent dynamic hepatic CT. RESULTS All nine lesions that were scanned within 60 s after initiating injections were detected as high density masses. However, 15 of 21 lesions (71%) that were scanned > 70 s after initiating injections could not be detected as high density masses. Using helical scanning, which permitted scanning the entire liver within 60 s after initiating injections, 27 of 31 lesions (87%) were detected as high density masses. CONCLUSION We concluded that most HCCs can be detected as high density masses during the early phase of dynamic CT using helical scanning.

Elective embolotherapy for recurrent hemoptysis was evaluated for its effectiveness. Forty embolotherapeutic procedures were performed in 30 patients. In the short term, complete hemostasis was achieved in 16 of 40 procedures (40%) and significant improvement in another 16 procedures (40%). Long-term, complete hemostasis was achieved in 14 of 34 procedures (41%) and significant improvement in 12 (35%). Embolotherapy was consistently more effective in patients who had no pleural abnormalities compared with those with pleural thickening. Long-term complete hemostasis was achieved in 7 of 10 procedures (70%) for the patients without pleural thickening and only 7 of 24 (29%) in patients with pleural thickening. Thus, pleural abnormalities negatively influence long-term effectiveness of embolotherapy.

The first aim of this study was to compare the detectability of metastasis of postoperative differentiated thyroid cancer (DTC) among (131)I whole body scintigraphy (IWBS), fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), and diffusion-weighted magnetic resonance imaging (DWI). The second aim was to clarify the association between the image pattern and prognosis.We evaluated 70 postoperative DTC patients on both a patient basis and an organ basis (lymph nodes, lung, bone), and we analyzed the correlation between the image pattern and the prognosis.For the patient-basis analysis, the detectability by IWBS, PET/CT, and DWI was 67.1%, 84.2%, and 57.6%, respectively. IWBS provided complementary information to that provided by PET/CT in 11 of 70 (15.7%) cases. For the organ-basis analysis, IWBS was the best detector for lymph node metastasis (72.4%). PET/CT was superior to IWBS for detecting metastasis of bone (85.7% vs. 71.4%) and lung (94.1% vs. 62.7%). For the correlation analysis, PET and DWI positivity were the factors predicting a poor prognosis.PET/CT was the best modality for detecting metastases in postoperative DTC patients, although IWBS provided complementary information. Because PET/CT and DWI gave similar information (e.g., positivity) suggesting poor prognoses, the combination of IWBS and DWI might be the method of choice for monitoring postoperative DTC.

Neoadjuvant chemotherapy (NAC) is commonly utilized to treat operable breast cancer. The purpose of this study was to review the findings of ultrasonography (US) and magnetic resonance (MR) imaging in patients treated with breast conservation surgery (BCS) after NAC with a focus on intrinsic subtypes. Eighty-six patients underwent BCS after NAC. The tumors were classified into four subgroups by receptor status. US and MR were performed before and after NAC. The tumor diameters in US and MR after NAC were examined for correlations with pathological tumor distances in the specimens from BCS after NAC. The correlation coefficient (r) of US to pathological tumor size was 0.3 in all tumors, 0.6 in HER2-type tumors, and 0.7 in triple negative breast cancers (TNBC). The correlation coefficient of tumor size in MR to pathological tumor size was 0.9 in TNBC, and other correlations were not statistically significant. The correlation between tumor size in MR and pathological tumor size in triple negative breast cancers corresponded best. This information is one of the clues to selecting patients for BCS after NAC.

Predicting liver functional reserve is important before partial hepatectomy. However, it is difficult to predict using morphologic imaging modalities, such as CT and MRI. In this study, we assess the usefulness of galactosyl human serum albumin (GSA) scintigraphy in predicting liver function recovery. We performed 99mTc-GSA scintigraphy before operation in 56 patients. Each patient was administered 185 MBq of 99mTc-GSA by intravenous injection. Serial images were taken immediately after the administration for 40 min. SPECT images were obtained to make a functional map. We calculated the functioning parameter residual GSA-Rmax (GSA-RL) using analysis software developed by Dr. N. Shuke. In addition, we compared GSA-RL with the morphological parameter residual liver volume (RLV-CT) calculated by conventional CT and serum albumin (Alb) or cholinesterase (ChE). We analyzed the correlation between imaging parameters and the postoperative recovery periods of serum albumin (r-Alb) and cholinesterase (r-ChE) and the values at 1 and 3 months for serum albumin (1M-Alb, 3M-Alb) and cholinesterase (1M-ChE, 3M-ChE). We found significant correlations between GSA-RL and r-Alb, r-ChE, 1M-Alb, 3M-Alb, 1M-ChE and 3M-ChE, but not between RLV-CT and the same parameters. The GSA-RL calculated by 99mTc GSA-SPECT was a useful parameter for predicting postoperative liver function recovery that should be implemented before partial hepatectomy.

The magnetic resonance imaging (MRI) features of sponges retained postsurgically in three patients are described. MRI depicted these as well-defined round masses, which were of low signal intensity on T1-weighted images and very high signal intensity on T2-weighted images. We scrutinized these masses on T2-weighted images. MRI revealed the low-signal-intensity structures to have wavy, striped, and/or spotted appearances, which raised the suspicion that they might be retained surgical sponges within mass lesions.

子宮内膜症患者12名にgestrinone (G) 5または10mg/週, 4～6ヵ月間投与し, 投与前卵胞期に, 投与中は2ないし4週ごとに, また投与後卵胞期にそれぞれ膣壁より検体を採取した.Pap標本により成熟指数 (MI) を観察し, 同時に採血してRIA法によりestradiol (E2), progesterone (P) およびtestosterone (T) 値を測定し, MIとホルモン値の推移およびそれらの相互の関係を検討した.G投与中は中層細胞が主体を成すため, これを細分して労基底細胞に近い小型中層細胞と, 表層細胞に近い大型中層細胞に分け, MIを労基底/小型中層一大型中層/表層の順で示して検討した.成績, 1) MIの平均値は投与前で0/15-40/45, 投与中の全期間で0/52-38/10, 投与後3ヵ月で0/22-41/37であった.労基底細胞は投与20週以後わずかに増加, 小型中層細胞は2週より増加 (p