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We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

Recently, the shift of the kaonic helium-4 2p state was precisely determined by the E570 and SIDDHARTA experiments. Prior to the experiment by E570, the average of three earlier experimental results showed - 43±8 eV, while most of the theoretical calculations give ∼ 0 eV. This five-sigma discrepancy between theory and experiment was known as the "kaonic helium puzzle". A recent theoretical model showed a possible resonance-like shift of maximum 10 eV for a certain value of a deep antikaon-nucleon interaction potential, which is different in helium 3 and helium 4. The E570 experiment determined the shift of the kaonic helium-4 2p state as +2±2 (stat)±2 (sys) eV in 2007. The SIDDHARTA experiment determined the shift as 0±6 (stat)±2 (sys) eV in 2009. The results of these experiments resolved the long-standing puzzle. A new experiment of the kaonic helium-3 X-ray measurement is being prepared by the J-PARC E17 collaborators, and the kaonic helium-3 X-ray data taken very recently by the SIDDHARTA experiment are on the way to be analyzed. The results of the E570, E17 and SIDDHARTA experiments examine the strong interaction for light nuclei with different isospin, and test furthermore recent theoretical predictions. © 2010 American Institute of Physics.

A super-fluid He 4 target system has been successfully developed to experimentally search for deeply bound K ¯ nuclei. From the experimental requirements, the amount of material around the liquid-helium target was drastically suppressed by using two approaches. One was to utilize the properties of super-fluid helium of extremely high thermal conductivity and low vapor pressure. The other was to develop a thin-walled CFRP vacuum chamber and a PET-based target cell. The wall thickness of the CFRP vacuum chamber was only 0.9 mm with the inner diameter of 310 mm. The dimensions of the target cell were 200 mm inner diameter and 150 mm length with the volume of 4.7 l, and it equipped 75 μ m thick beam windows made of a PET film. The present target system achieved a temperature of 1.3 K, and was stably operated throughout the experiment with the operational pressure below 40 mbar and a liquid-helium consumption rate of 45 l / day .

A polarized deuterium target was developed for the use of the first measurement of the so-called complete spin dependent cross-sections of the D → ( d → ,p)T nuclear reaction at 20 MeV . In order to minimize the energy losses of incident and emitted particles in the target materials, the target thickness should be as thin as possible. A deuterated polyethylene foil of 30– 50 μm thickness was used as polarized target. The deuterons contained in the foil are polarized by the dynamic nuclear polarization method in the magnetic field of 2.5 T . The polarized deuterium target system has been installed in the 1st experimental hall of the Tandem Accelerator Center at the University of Tsukuba. From the target asymmetry measurement of D → (d,d)D elastic scattering by a 20 MeV deuteron beam about 10% deuteron target polarization was confirmed.

A 15.5 T superconducting magnet and a variable temperature insert (VTI) system were installed at a radiation control area in Oarai center in Tohoku University to investigate the superconducting properties of activated superconducting materials by fast neutron. The superconductivity was measured at cryogenic temperature and high magnetic field. During these tests, some inconvenient problems were observed and the additional investigation was carried out. The variable temperature insert was designed and assembled to perform the superconducting property tests. without the liquid helium. To remove the heat induced by radiation and joule heating, high purity aluminum rod was used in VTI. The thermal contact was checked by FEM analysis and an additional support was added to confirm the decreasing the stress concentration and the good thermal contact. After the work for improvement, it was affirmed that the test system works well and all troubles were resolved. In this report, the improved technical solution is described and the first data set on the irradiation effect on Nb3Sn wire is presented.

We will measure the x‐rays from kaonic 3He and 4He 3d→2p transition by using silicon drift detectors. Our precision goal is set to 1 eV to provide crucial information on the kaon‐nucleus strong interaction in the low energy limit. The experiment is to be performed as one of the first experiment in the J‐PARC hadron facility (J‐PARC E17). An overview and the present status of the experiment are presented.

We present an experimental study of Λ(1405) via the in‐flight (K−,n) reaction on the deuteron target (J‐PARC E31). We will measure all Σ+π−, Σ−π+ and Σ0π0 final states so that the isospin structure of the produced hyperon resonance state can be decomposed. In this report, we present an overview of the experiment and preparation status.

The perovskite type manganite systems, Ln1−xSrxMnO3 (Ln=La, Pr, Nd, Sm, and Gd; 0 ≤ x ≤ 0.5 ) were studied as the electrode materials for solid oxide fuel cells (SOFC) from the view point of applications to the co-firing process of the electrolyte and electrode at a higher temperature. The reactivity tests with yttria-stabilized zirconia (YSZ) showed that the formation of the pyrochlore Ln2Zr2O7 was suppressed for the perovskites having smaller lanthanoids than La, especially for the Pr1−xSrxMnO3 and Nd1−xSrxMnO3 systems. No reaction product appeared between the Ln1−xSrxMnO3 perovskite and YSZ even at a high annealing temperature of 1400°C when the lanthanoid elements were Pr, Nd and Sm and the Sr content was around 30% (x=0.3). The adjustment of the thermal expansion rate of Ln1−xSrxMnO3 to YSZ needed more Sr substitution with an increase of the atomic number of lanthanoids. The Sr contents, x, showing comparable values with 8m/o YSZ were around x=0.1–0.2 in La1−xSrxMnO3, 0.3 in Pr1−xSrxMnO3 and Nd1−xSrxMnO3 and more than 0.4 in Sm1−xSrxMnO3 and Gd1−xSrxMnO3. The electrical conductivity, which may strongly relate with the polarization of electrode reaction, showed about 200 S/cm at 1000°C for all Ln0.7Sr0.3MnO3 systems. The polarization measurements as an air electrode showed no significant dependence on the kind of lanthanoid elements. From the viewpoint of the electrode activity, high electrical conductivity, low reactivity and good compatibility with YSZ, Pr0.7Sr0.3MnO3 and Nd0.7Sr0.3MnO3 are considered to be the most suitable electrode materials for the co-firing process.

The energy dependence of the partial cross sections of electron-impact dissociation of SF 6 into the neutral radicals SF, SF 2 and SF 3 is measured from the threshold to 200 eV. This measurement is accomplished by appearance mass spectrometry in a dual electron beam device. The dissociation products SF 4 and SF 5 are below the detection limit of the present system. The threshold energies for neutral dissociation into SF 3 , SF 2 and SF are measured to be 16.0, 19.5 and 22.0 eV respectively. The surface loss probability of each radical and the electron-impact nitrogen dissociation are examined to evaluate the relative dissociation cross section. However, the absolute cross section cannot be assigned for lack of the ionization cross sections for the SF x radicals.

We will measure the X‐rays from kaonic 3He 3d → 2p transition with a precision below 2 eV. It can provide crucial information on the kaon‐nucleus strong interaction. The experiment (J‐PARC E17) will be performed as Day‐1, which is one of the first experiments in the J‐PARC hadron facility in the year 2011. An overview and the present status of the J‐PARC E17 experiment are described.

This paper deals with the effect of magnetic bias of Acoustic Vibration Element using Giant magnetostrictive material (AVEG) which is a low frequency transducer for an man acoustic tomography system. By measurement of magnetostriction characteristics, it is shown that the magnetic bias by magnet is a suitable value and the dynamic range must be less than I= ± 1[A].The authors analyzed the magnetic circuit of AVEG and calculated the value of magnetic bias field.And the structure of the magnetic circuit was evaluated with the next distinctive parameter. variation rate of magnetic dux density in the vibrator, effective rate of flux, and sensitivity of magnetostriction.

Limiting current type oxygen sensors using a thin-film zirconia electrolyte and platinum electrodes have been reported previously. However, for this configuration, in which the electrolyte resistance is minimized, the sensor performance may be dominated by the electrode interface resistance. Accordingly, an improved sensor with graded-composition layer electrodes (GLE) has been developed to reduce the electrode interface resistance in such a device. Sensors fabricated with GLE displayed good linearity and high stability to oxygen concentrations from 0% to 100%, due to a decrease in the electrode interface resistance.

Some types of chronic diseases, which are considered relevant to obesity, an excess storage state of fat in the body, cause public health as well as financial problems in many industrialized countries. The obese state occurs when genetic and environmental factors meet certain conditions. It would be desirable if we find food components which can prevent the obesity. We have tried to seek for such components in herb teas because those teas are usually taken on every day basis. We used cultured pre-adipocyte 3T3 L-1 cells to screen herb teas for factors affecting the fat deposit in the cells. Then, we performed an in vivo test using rats and an extract from Houttuynia cordata.

To determine the pathologic basis for low-intensity nodules seen on MR images of the liver in patients with cirrhosis, we obtained spin-echo and gradient-echo MR images in 20 cirrhotic patients in whom partial hepatectomies were subsequently performed for hepatocellular carcinoma. Low-intensity liver nodules were shown on gradient-echo and spin-echo images in eight patients. Pathologic study of the liver in these patients showed that these nodules were regenerating nodules containing hemosiderin. Low-intensity nodules were seen only on T2-weighted spin-echo images in four other patients. Microscopic examination of the liver in these patients showed regenerating nodules without hemosiderin deposits. Broad fibrous septa containing vascular spaces were present in two of these four patients. These results suggest that regenerating nodules containing hemosiderin or those that are surrounded by vascular fibrous septa are visible on MR images as low-intensity nodules and that gradient-echo images are useful in demonstrating nodules with hemosiderin.

A case of hemimegalencephaly was studied by means of neuroimaging (CT, MRI and PET) and magnetoencephalography (MEG). Hemimegalencephaly (HM) is a neuronal migration disorder. This is the first report of evaluation of HM with the use of PET and MEG from not only the morphological but also the functional point of view. PET with 11C-glucose showed a low radioactive concentration in the affected hemisphere, which suggested a metabolic deficit. MEG proved the epileptic foci existed mainly in the affected hemisphere, especially around a heterotopia and the pachygyric cortex, which was disclosed on MRI.

Surgical treatment for a hypoplastic aortic arch associated with coarctation or interruption of the aorta is controversial. We evaluate the changes of diameter of proximal transverse aortic arch after surgery in 28 patients. Proximal transverse aortic arch in all patients was preoperatively 3.5 +/- 0.9 mm (2.5 to 7 mm), and 54 +/- 12% (36 to 84%) to the normal aortic valve dimension (n-AVD: 16.6 X BSA0.6). While postoperative proximal transverse aortic arch was 6.5 +/- 1.8 mm, and 76 +/- 12% to the n-AVD, and significantly grew more than the preoperative arch dimension (p = 0.0001). In 18 patients having two times cardiac catheterization postoperatively, proximal transverse aortic arch was 6.5 +/- 1.6 mm, and 75 +/- 13% to n-AVD on the 1st postoperative examination. On the 2nd examination, the arch was 9.9 +/- 1.9 mm, and 88 +/- 12% to n-AVD, and significantly grew with increasing years (por = 0.0003). We concluded that the proximal transverse aortic arch, which was more than 36% to n-AVD in diameter, if not dilated surgically, grew with increasing years after aortic arch repair.

Left ventricular outflow tract (LVOT) dimension was measured in seven patients with coarctation (CoA) or interruption (IAA) of the aorta before and after aortic arch repair and pulmonary artery banding. The age of patients ranged 3 to 69 (mean 16) days, the weight 3.0 to 3.9 (mean 3.4) kg. Associated cardiac anomalies were VSD in 6, MA and DORV in 1. In five patients compared by ultrasound, preoperative LVOT dimension ranged from 3.5 to 5.0 (mean 4.4) mm with the ratio to the normal aortic valve dimension (n-AVD; 16.6 x BSA0.6) from 54 to 82 (mean 69)%. Postoperative dimension increased 5.0 to 7.4 (mean 5.7) mm and the ratio to the n-AVD increased 65 to 89 (mean 80)%. In three patients compared by LV graphy, preoperative LVOT dimension ranged from 4.0 to 4.5 (4.2) mm and the ratio ranged from 61 to 72 (68)%. Postoperative dimension increased from 4.5 to 6.7 (5.3) mm, and 74 to 80 (78)% to n-AVD after operation. Postoperative pressure gradients between LV and ascending aorta in each patient were 1 to 9 (mean 6) mmHg. In any patients, LVOT obstruction did not advance after aortic arch repair and pulmonary artery banding.

Carbon-11-methionine PET scans were obtained from 24 patients with non-small-cell lung carcinoma for whom surgical treatment was considered. The tumor mass was visualized with clear delineation. After PET scanning, the tumor was removed by lobectomy or pulmonectomy. The tumor tissue was first processed to yield tumor cell suspensions and then subjected to DNA flow cytometry. Comparison between 11C uptake rate and flow-cytometric data gave the following results: 11C uptake rate in the tumor correlated well with the cellular DNA content (DNA index) of tumor cells at the resting state of cell division (G0 + G1-phase) (r = 0.67). The correlation between 11C uptake rate and S-phase cell percentage was markedly high (r = 0.76), and the correlation between 11C uptake rate and S+G2/M-phase cell percentage was extremely high (r = 0.86). It was concluded that the tumor uptake rate of 11C-methionine was representative of tumor growth rate in this tumor type.

Positron emission tomography (PET) was performed on six patients with the Rett syndrome and the results were compared with the concurrent clinical status of the patients. The cerebral metabolic rate of oxygen (CMRO2) was low in five patients, and oxygen extraction fraction (OEF) was low in four patients; both had a tendency to decline with advancing age. Although the cause is unknown, it is suggested that impaired oxidative metabolism exists in the Rett syndrome. An analysis of the distribution among brain regions showed that the ratios of values for the frontal cortex to those for the temporal cortex for both the cerebral blood flow (CBF) and CMRO2 were lower than those for the controls, which may indicate the loss of hyperfrontality in the Rett syndrome. Distribution of brain metabolism may be immature in the Rett syndrome.

We have measured regional alveolar volume and regional ventilation of emphysematous lesions and periemphysematous lesions with positron emission tomography and N-13 gas in 10 patients. The purpose of the study was to investigate how emphysematous lesion develops. The subjects were all male (except one) who put on a mask in supine position, and were connected with a spirometer. We gave N-13 gas in this closed circuit and had the gas rebreathed by the subjects. After activity reached equilibrium in closed circuit, an equilibrium scan was made. We took "activity gas" from the closed circuit and measured activity by well counter during equilibrium to get quantitative alveolar volume. The activity in closed circuit during equilibrium showed activity in the thoracic unit. After equilibrium, we used air to wash out radioactive gas from the circuit. During washout we took 3 sequential images. The decreased rate of activity in the region of interest from these 3 sequential washout images was expressed in a monoexponential curve. The index of monoexponential denotes V/V. Alveolar volume in emphysematous lesions was 34.8 +/- 19.5 ml/100ml thoracic volume, and V/V in these lesions was 0.27 +/- 0.21/min. On the other hand alveolar volume in periemphysematous lesions was 76.5 +/- 13.1 ml/100ml thoracic volume, and V/V was 0.38 +/- 0.22/min. Thus alveolar volume in periemphysematous lesions was relatively high. These results indicate that the effect of emphysematous lesions as compared with periemphysematous lesions was not direct compression of alveolar space. The direct effect was compression to the bronchiole of peripheral lesions, and check valve mechanism occurred in the bronchiole causing peripheral lesions resulting in the destruction of the alveolar wall.

Twenty-two patients with tetralogy of Fallot and pulmonary atresia underwent cardiac catheterization and angiocardiography late after repair. In ten patients, the disease was not associated with the major aortopulmonary collateral artery (MAPCA), but in 12 patients, the disease was associated with it. Three patients died after restudy, two because of pulmonary hypertension and one because of pneumonia. Pulmonary artery mean pressure was 15-92 (28 +/- 21) mmHg, being higher in 75% of the patients with MAPCA than the normal range. The number of pulmonary artery subsegments connected to the central pulmonary arteries was determined from pulmonary arteriography, being 22-42 (38 +/- 6). Pulmonary artery mean pressure and pulmonary vasculature resistance (PVR), 0.8-35.2 (10 +/- 9), inversely correlated with the number of the centrally connected pulmonary artery subsegments (r = -0.81, p less than 0.001 vs PAP, r = -0.85, p less than 0.001 vs PVR). PVR per subsegment also inversely correlated with them (r = -0.81, p less than 0.001). These findings suggest that pulmonary vasculature resistance is abnormally high in this disease, and increase as the number of the centrally connected pulmonary artery subsegments decrease.

From 1968 to 1987, 45 consecutive patients with tetralogy of Fallot and pulmonary atresia underwent corrective surgery. In the former 10 years, there were 8 operative deaths (40%) in the 20 patients and no late death. In the recent 10 years, there were 4 operative deaths and 4 late deaths in the 25 patients. In the 17 patients associated with large aorto pulmonary collateral artery (LAPCA) which was ligated in the most patients, there were 5 operative deaths (29%) and 3 late deaths. Nine patients (53%) survived long-term. There were 7 operative deaths (25%), one late death and 20 patients (71%) being long-term survivors in the 28 patients without LAPCA. Pulmonary hemodynamics were investigated in 10 patients without LAPCA and 11 with LAPCA after corrective surgery. Pulmonary arterial mean pressure (PAm) ranged from 9-24 (17 +/- 6) mmHg in patients without LAPCA and 15-92 (37 +/- 23) mmHg in those with LAPCA. Pulmonary arteriography showed arborization abnormality in 7 of the 11 patients with LAPCA. PAm inversely correlated well with number of pulmonary artery segments connected to the central pulmonary arteries. Postoperative pulmonary hypertension was found in patients with less than 16 bronchopulmonary segments connected to the central pulmonary arteries, and two of them died of pulmonary hypertension late after surgery. These results suggested that unifocalization to connect the central pulmonary artery more than 15 bronchopulmonary segments may be an important strategy for correction of this anomaly with LAPCA.

We have measured quantitative regional alveolar volume and specific ventilation in healthy subjects by Nitrogen-13 gas and Positron Emission Tomography. Studies have proceeded in the supine position. Subjects have rebreathed N-13 gas in closed circuit. After radioactivity has reached equilibrium, Scan was carried out. During equilibrium, we have taken radioactive gas from the closed circuit to make quantitative alveolar volume and we have measured the radioactivity by well counter. This value means radioactivity in unit of thoracic volume. Well counts/PET counts denote alveolar volume/thoracic volume. After equilibrium, RI has been washed out by air, during the washout phase we have 3 sequential images. Using these sequential images, we have fitted RI activity in the washout phase monoexponential curve. Index of the monoexponential curve means -V/V, if we do not consider rebreathing from dead space. The data shows a large alveolar volume in the ventral region compared to that in the dorsal region, and also a high V/V in the dorsal region compared to that in the ventral region. It seems that the error of V/V in healthy subjects due to rebreathing from dead space is about 8%.

Follow-up magnetic resonance imaging (MRI) and computed tomography (CT) examinations were performed on five patients with Wilson's disease at intervals from 6 to 29 months. We studied the clinical correlation with MRI and CT, and whether the examination of MRI and CT could be useful for evaluation of the therapeutic effect. Positron emission tomography (PET) was also carried out on 4 cases except for an asymptomatic case (patient 2, sister of patient 1). Close relationship has been observed by MRI between dystonia and the lesion of the lenticular nuclei, abnormality of smooth pursuit eye movements and the brain stem lesion, and severe dysarthria/dysphagia and the lesion of the caudate and lenticular nuclei, respectively. In patient 4, repeated MRI of an interval of 18 months demonstrated decrease of the abnormal high signal in the lateral part of the putamen on T2-weighted image in accordance with marked improvement of clinical manifestations. In patient 3, who had severe dystonia of the extremities and trunk, T2-weighted image showed high signals in the lenticular nuclei. Marked decrease of the high signal in the lenticular nuclei was observed by MRI in this patient after 29 months, when her neurological manifestations were markedly improved. Patient 5 with severe cerebellar signs disclosed abnormal signals in the middle cerebellar peduncles, brain stem and dentate nuclei in addition to low signals in the caudate and lenticular nuclei, and high signals in the lateral part of the putamen on T2-sequence.(ABSTRACT TRUNCATED AT 250 WORDS)

99mTc-SQ30217 555 MBq (15 mCi) was intravenously injected to 6 healthy subjects to study its safety, pharmacokinetics and the imaging time. Neither side effects nor abnormalities in physical findings, hemato-biochemical tests, urinary test, etc. caused by this agent were observed in any case and its safety was suggested. Radiation dose estimates over the entire body was 4.88 mGy/1,110 MBq (0.488 rad) and that over the major organs was less than 10 mGy and they were within the allowable ranges. 99mTc-SQ30217 showed biphasic disappearance curve in blood with the half-life of alpha-phase 0.02 hour and that of beta-phase 10.14 hours. 99mTc-SQ30217 was considered to show characteristic pharmacokinetics in that the myocardial accumulation was high in an early stage of the administration, but it rapidly decreased. Both heart to liver ratio and heart to lung ratio were high within 10 minutes, but they decreased after 15 minutes. As a result of SPECT imaging of 4 patients with ischemic cardiac disease, the images obtained with 99mTc-SQ30217 at an early period after the administration was as good as those with 201Tl and the appearance of defects in the images with both agents was similar. 99mTc-SQ30217 was considered to be sufficiently useful as a 99mTc-labelled agent for myocardial blood flow.

To predict the coronary artery bypass graft(CABG) flow based on the time density curve(TDC) obtained from the digital subtraction aortograms(DSA), we developed a pulsatile CABG model (perfusion pressure 60, 130 mmHg, pulse rate 53, 126/min, cardiac output 3-7 l/min, diameter of the graft 2.1-6.0 mm). After positioning the regions of interest (ROI), we injected contrast medium (5-40 ml/sec, 5-40 ml) into the outlet conduit. Concerning the TDCs, we calculated appearance time(Ta), peak densities(Dp), peak time(Tp), disappearance time(Td), integral of TDC, delta Tp (difference of Tp between two ROI) and delta Ta (difference of Ta between two ROI).Perfusion pressure, graft flow and output curve were similar to those of patients with CABG. Ta, Tp, Td and delta Tp were affected by both the injection rate and the volume of the contrast medium; while Dp and the TDC integral were only affected by the latter parameter. Under the same conditions of contrast medium injection, the TDC depended strongly on graft flow, diameter of the graft, output and pulse rate. 21.6 + 0.92 pi.d2/4.delta 1/delta Tp.60 provided the most accurate estimation of CABG flow (r = 0.865, p less than 0.01). We conclude that densitometric analysis of DSA may be useful in the prediction of CABG flow.

Treatment of cerebral vascular lesions such as carotid cavernous sinus fistulas and giant aneurysms is now being performed with intravascular detachable balloon embolization techniques. We have developed several types of all-silicone detachable balloons. Our balloons have self-sealing valves (with or without collars) and detach with simple traction. The self-sealing valve is smaller than 0.6 mm and the balloon can easily be placed through a 7-F catheter. We started clinical trials and a representative case was reported.

We examined pyruvate turnover using 1-[11C]pyruvate in the brain and epicranial muscle of 6 patients with mitochondrial encephalomyopathy (MEM), diagnosed by muscle biopsy and mitochondrial enzyme assay. The radioactivity was measured by positron emission tomography (PET). The time-activity curve for 11C in both brain and muscle generated after i.v. injection of 1-[11C]pyruvate consisted of 2 components in normal subjects and patients, i.e. a fast and a slow component which were assumed to represent the aerobic (mitochondrial) and anaerobic (glycolytic) metabolism of pyruvate, respectively. In the brain and muscle of patients, the aerobic component was smaller and the anaerobic larger than in normals. The extent of this abnormality seemed to reflect the severity of the disease. The same slight abnormality for [11C]pyruvate turnover was also observed in the brain of MEM patients who were without cerebral symptoms. Cerebral blood flow (CBF) and cerebral oxygen consumption (CMRO2) of most patients were lower than those of normals, and the oxygen extraction fraction (OEF) was decreased in many patients.

This study was designed to investigate the differences in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) between patients with dementia of frontal lobe type and patients with Alzheimer's disease. Positron emission tomography (PET) using 15O steady state inhalation technique was carried out in 5 patients with a clinical diagnosis of dementia of frontal lobe type and 7 patients with a clinical diagnosis of Alzheimer's disease. CBF and CMRO2 were significantly decreased in the frontal cortex except for precentral region in patients with dementia of frontal lobe type in comparison to those values in patients with Alzheimer's disease. However, in patients with dementia of frontal lobe type CBF and CMRO2 in the parietal cortex and the occipital cortex were relatively preserved when compared with patients with Alzheimer's disease. In comparison with values for CBF and CMRO2 in the posterior part of brain [frontal or temporal/(parietal + occipital)/2 ratio], both values in the frontal cortex were markedly decreased in all 5 patients with dementia of frontal lobe type, but there was no marked reduction in the frontal cortex in patients with Alzheimer's disease. In addition, in 2 patients with dementia of frontal lobe type whose duration of the disease was more than 7 years, CBF and CMRO2 in the temporal cortex were markedly reduced in comparison with values in the posterior part of brain. These results suggested that PET findings of marked reduction in CBF and CMRO2 in the frontal cortex are useful to distinguish dementia of frontal lobe type from Alzheimer's disease.

In 21 patients with chronic liver disease, the ratio of liver to muscle signal intensity on T1-weighted images was negatively correlated with the progression of hepatic fibrosis defined according to findings by laparoscopy and liver biopsy, and differentiated six patients with early chronic hepatitis from eight with liver cirrhosis. On T2-weighted images, the number of low intensity nodules comparable in size to regenerating nodules surrounded by connective tissues showed a positive correlation with stage. When hepatic fibrosis with no necrosis or fat infiltration was induced in rats, T2 values were positively correlated with hepatic hydroxyproline content, though there was no such correlation for T1 values. These results suggest that MR imaging may be useful for determining the progression of hepatic fibrosis in chronic liver disease. T2 values may directly reflect hepatic fibrosis.

The coronary vein has few variations. We describe a case of coronary vein with an unusual course. In this case, the coronary vein entered the umbilical portion of the left portal vein directly, whereas it usually flows into the portal trunk or splenic vein. The angiographic appearance is presented.

Six patients had nine kidneys with lymphoma. Five patients (83%) had non-Hodgkin lymphoma, and three (50%) bilaterally. There were multiple nodules in four kidneys (44%). The lesions were changeful in the course. Gallium scintigraphy showed abnormal uptakes. Magnetic resonance imaging was examined in one case. The lesions were hypovascular in the angiographies. Inflammation is one of the different diagnosis.

A case of retrocaval ureter associated with double inferior vena cava, an exceedingly rare venous anomaly, is reported. This anomaly was correctly diagnosed by CT. CT after intravenous contrast injection showed the double inferior vena cavae on both sides of the abdominal aorta and the right ureter crossing the right inferior vena cava posteriorly. CT is a good diagnostic modality with which to demonstrate such a vascular anomaly, and the clinical usefulness of CT is stressed.

Tl-weighted MR images of thirty-six hips in 25 patients with avascular necrosis of the femoral head were obtained two to five times during the course of 2 to 26 months. We investigated these MR images in the light of the chronological change and compared them with plain radiographs. MR images change in 16 femoral heads; in general, the abnormal low intensity area in the femoral head reduced in extent and the internal high intensity area became smaller of disappeared. Thirteen femoral heads among them became more flattened on plain radiographs in the same period. It is noted that four different zones are defined in the femoral head after bone necrosis takes place: the dead bone marrow, the dead marrow which still contains fat, the reactive interface and the hyperemic bone marrow. In Tl-weighted MR images, the dead bone marrow, the reactive interface and the hyperemic bone marrow are demonstrated as low intensity area, while the dead marrow containing fat may remain high in intensity. On the basis of this knowledge of histopathology and MR images of this disease, we suggest that reduction of the abnormal low intensity area and disappearance of the internal high intensity area on MR images can be regarded as diminution of hyperemia in the living bone marrow and loss of fat in the dead bone marrow, respectively.

This paper presents our ongoing project in which normal human anatomy and its quantitative data are systematically arranged in a computer. The final product, the Computerized Three-Dimensional Normal Atlas, will be able to supply tomographic images in any direction, 3-D images, and coded information on organs, e.g., anatomical names, CT numbers, and T1 and T2 values.

Four patients with idiopathic transient osteoporosis of the hip were examined by magnetic resonance imaging (MRI). MRI clearly showed low signal intensity in the affected femoral head on T1-weighted images and high signal intensity on T2-weighted images. After regression of hip pain, MR images became normal. MRI was a useful method for diagnosis and follow-up study of idiopathic transient osteoporosis of the hip.

Thin (2mm) section contiguous computed tomographic (CT) scans were obtained through the bronchi of the right upper lobe and the left upper division in 30 patients. All segmental bronchi were identified. The right subsegmental bronchi were identified in 100%, and the left subsegmental bronchi in 97%. The type of the orifice of the right bronchus was trifurcated (53%), the extension of B1 was apicoanterior (50%), and the size of B2b was equal to B3a (63%). The extension of the left B3 was subapicoanterior (38%), and the size of B1+2c was equal to B3a (62%).

T1 and T2 weighted MR images were compared in 32 hips with avascular necrosis, and the difference between them was discussed. In 27 of 32 hips, abnormal low intensity area in the affected femoral head is smaller in T2 weighted images than in T1 weighted images. The area of low intensity on T1 weighted image and high on T2 weighted image might be granuloma in reactive tissue and surrounding hyperemia. The difference between T1 and T2 weighted images must be taken into consideration especially in determination of the border of affected bone.