[en] The outburst of the X-ray pulser A 0535+26 was observed, and the results of data analysis are reported in this paper. The outburst was detected on October 2, 1980, by the SVC 1/2 counter loaded on 'Hakucho'. The maximum of X-ray intensity was seen on October 10, then the intensity began to reduce, and the intensity on November 3 was not detectable. The energy spectrum of X-ray became soft for the period of 25 days. The outbursts of A 0535+26 have occurred at intervals of about 110 days. The pulse period on the October 9 was 103.67 sec, and became 103.61 sec on October 22. The period was constant for the period from October 22 to November 3. Discussion on this variation is presented. The analysis of pulse delay time was performed. The delay time data were on a smooth delay curve. This shows a Doppler effect of the revolution of A 0535+26. The eccentricity of the orbit of revolution was given by the chi-square analysis. (Kato, T.)

[en] We present a case of a patient with rapid deterioration of esophageal varices caused by portal hypertension accompanied by a large arterioportal shunt that developed after radiofrequency ablation of hepatocellular carcinoma. We used n-butyl cyanoacrylate (NBCA) as an embolic material to achieve pinpoint embolization of the shunt, because the microcatheter tip was 2 cm away from the shunt site. Under hepatic arterial flow control using a balloon catheter, the arterioportal shunt was successfully embolized with NBCA, which caused an improvement in the esophageal varices.

[en] Tenma observations were made of the transient 4.4-s X-ray pulsar X0331+53 (V0332+53) at several phases of its 34-d binary orbit during the period November 1983-January 1984. The measured X-ray flux and pulse periods agree with those obtained with EXOSAT. Rapid random fluctuations in the X-ray emission from this source were studied. It appears that this type of variability is not rare among accreting pulsars, but is particular noticeable in X0331+53 due to the small pulse fraction. The X-ray spectra show a turn-over above ∼15 keV, which is better described by a recently introduced cyclotron absorption formula than the commonly used exponential cutoff model. This also applies to the spectra of Her X-1 and Cen X-3. In terms of this model, a magnetic field strength of ∼3 X 10¹² G is suggested for X0331+53. The absence of iron K-emission lines in the spectra indicates a rather small circumstellar matter density. This, together with the observed high luminosity (∼3 X 10³⁶ erg s^-1) and large intensity modulation along the orbit, suggests that the pulsar is powered by accretion from the equatorial envelope of the supposedly Be-type primary (BQ Cam). (author)

[en] A 73-year-old woman with a large esophagorespiratory fistula underwent bronchoscopy and computed tomographic (CT) virtual endoscopy before stenting. Noninvasive CT virtual endoscopy showed the large fistula, and the CT findings agreed with the bronchoscopic findings

[en] The treatment for pediatric craniopharyngioma remains challenging and controversial. Although this tumor is histologically benign, the treatments include radical surgery, conservative surgery, radiotherapy, intracystic chemotherapy and multimodality approaches. In addition, the long-term functional outcomes including visual function, endocrine function, cognitive function, hypothalamic function, and quality of life are complex and major problems among survivors. In this paper, we reviewed the recent treatments for pediatric craniopharyngioma and the long-term outcomes after treatment in literatures. (author)

[en] The x-ray pulsar 4U 1626 - 67 was observed with Tenma during the period May 3 through 5, 1983. No appreciable change in the spectrum was observed during x-ray flares. The pulse period of 7.671350 s and the rate of period change are consistent with a stable spin-up at a rate of ∼ 2 x 10^-4 yr^-1. The pulse profile changes drastically at about 15 keV and 2 keV, and the energy spectrum depends on the pulse phase accordingly. No emission line feature of iron around 6 keV was found with an upper limit of the equivalent width of 60 eV (90 % confidence). The observed energy dependence of the x-ray pulse profile was simulated by a calculation based on the anisotropic radiation transfer in a strongly magnetized plasma with a magnetic field strength of ∼ 8 x 10¹² G at the neutron star surface. (author)

[en] Her X-1 was observed during an on-state of the 35-d cycle in May 1983 with the gas scintillation proportional counters on board Tenma. The declining phase of the on-state is characterized by two progressive features: (i) decrease of the main-pulse amplitude, and at the same time (ii) increase of absorption column of relatively cool matter. However, the photoelectric absorption in this cool medium does not explain the feature of the main pulse decrease which occurs at all energies. The spectral shape after the correction for photoelectric absorption is found to remain essentially the same through the main-pulse decrease. This may be interpreted as due to an attenuation of X-ray beam by electron scatterings in a highly ionized plasma at an estimated distance of --3 x 10⁸ cm from the neutron star. In the last part of the on-state, the main pulse was reduced to become invisible and a simple ''sinusoidal'' form was observed. In this period, a steady phase advance of 18+-5 ms h^-1 is detected. The X-ray observed in this period are probably those scattered from the surrounding medium, and the observed phase advance is explained by that the scattering region for the observed X-rays moves opposite to the direction of the neutron star rotation. (author)

[en] Positron emission tomography (PET) with 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG) has been established in the diagnosis of brain tumors. FDG enables the detection of brain tumor because of increased glucose consumption. However, high cortical glucose metabolism limits the capacity of FDG-PET to distinguish tumor tissue from normal brain tissue. PET with L-[methyl-¹¹C]methionine (MET) provides information on the amino acid uptake in brain tumors. MET-PET has been shown to possess high specificity in tumor detection, tumor delineation, and differentiation between malignant and benign lesions. Various studies have demonstrated a significant correlation between tumor grade and MET uptake in glioma. Our recent experience revealed a significant difference in maximum standardized uptake value (SUV_max) of MET between grade II (3.05±1.42, n=14) and grade IV (4.08±1.05, n=13) gliomas (P<0.001). However, no significant difference was observed in MET SUV_max between grade II and grade III (3.99±1.46, n=14) gliomas. More specifically, studies have demonstrated relationships between MET uptake and tumor proliferation and angiogenesis. A positive correlation was observed between the individual MET SUV_max and Ki-67 indices in our patients (r=0.49, P=0.0011). MET-PET has also been applied for the guidance of stereotactic biopsy and open tumor resection. Many studies have reported the use of MET-PET to investigate the effectiveness of therapy and prognosis of glioma. Moreover, MET-PET is highly sensitive for differentiating between tumor recurrence and radiation necrosis following radiotherapy in patients with glioma and metastatic brain tumor. In spite of several limitations, MET-PET has become a recent 'gold standard' in brain tumor diagnosis and treatment strategy design, especially in glioma. PET with [¹⁸F]-fluoro-3'-deoxy-3'-L-fluoro-thymidine (FLT) provides information about cellular proliferation activity and has been examined in malignant brain tumors. FLT-PET is sensitive in detecting malignant glioma due to the very low background uptake in normal brain tissue. However, the ability to detect low grade glioma and tumor extension appears to be lower for FLT than for MET. Recent studies have found a correlation between World Health Organization (WHO) tumor grade and FLT uptake in gliomas. Our recent experience demonstrated a significant difference in FLT SUV_max between grade II (0.27±0.06, n=6) and grade IV (2.18±0.93, n=10) glioma (P<0.0001), and grade III (0.70±0.45, n=7) and grade IV glioma (P<0.001). FLT uptake showed a significantly higher correlation with the Ki-67 index (r=0.86, P<0.0001) than did MET uptake in gliomas. Studies have also reported the use of FLT-PET to investigate the effectiveness of therapy and prognosis in glioma. Increased FLT accumulation is also observed in other brain tumors including malignant lymphoma and metastatic brain tumor. Additional investigation and understanding of each PET tracer characteristics may further validate the use of PET imaging in brain tumor diagnosis and treatment. Advancement of PET molecular imaging technique using [¹⁸F]fluoromisonidazole (FMISO) provides a noninvasive assessment of hypoxia in malignant glioma and is prognostic for treatment outcome. FMISO-PET may have a further role in directing patients towards targeted hypoxic therapies. (author)

[en] The purpose of this study was to explore the optimal contrast material (CM) concentration for distinguishing CM, carotid stent (CS), and neck components in cone-beam computed tomography (CBCT) during carotid angiography (CBCT-CA). A neck phantom containing CS and contrast-filled imitation vessels of 9 mm diameter was scanned using CBCT. CM (300 mgI/ml) was used in concentrations of 100, 50, 33, 10, 5, and 1%. In a clinical study, 30 patients with a CS (Precise or Wallstent) underwent CBCT-CA with CM injected at a rate of 3 ml/s and a concentration of 10 or 20%. In the basic study, CBCTA using 5% CM enabled clear distinction among the three components under windowing at 1500 width and 300 center, and showed the exact diameter of the imitation vessel. Pixel values of CM inside the Precise and the Wallstent were 622.2±32.9 (mean±SD) and 746.0±27.9, respectively. In the clinical study using CM at concentrations of 10 and 20%, pixel values of CM inside the Wallstent were 632.3±69.2 and 1024.5±99.0, respectively. Optimal CM concentration for distinguishing among the three components was 5% in the basic study; the optimal concentration was 10% in the clinical study. (author)

[en] A new model is proposed for the spectrum of a type II burst from the 'rapid burster'. The spectrum of a type II burst has been considered to be well fitted with a blackbody spectrum with temperature T about 1.5 keV. Recent observations with Tenma and Exosat, however, have found an excess from the blackbody spectrum in the high-energy range (E greater than 10 keV). The high-energy component is approximated to be a power-law spectrum of f(E) proportional to E exp -4, where E and f(E) are the X-ray energy and observed counts per unit energy, respectively. The model explains this high-energy component gives a method to evaluate the velocity and the optical depth of the accretion flow from observations of the high-energy component. It is shown that the spectrum observed with Tenma can be fitted with the model. 33 refs