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Didriksen Voigt opublikował 1 rok, 3 miesiące temu
CT angiography provided specific information such as detecting the presence, location, and number of PVT in dogs. Therefore, CT angiography might be useful for the diagnosis and follow-up evaluation of PVT in dogs.This study investigated the effect of heat-killed Lactobacillus sakei HS-1 (HK-LS HS-1) on the health and fecal bacteriological change of suckling Japanese Black calves as a supplement in milk replacers. Twelve calves were separated from dams to calf-hatch after calving for milk replacers feeding. They were randomly assigned to an HK-LS HS-1 supplement or a control without HK-LS HS-1 group in milk replacers. HK-LS HS-1 was administered from separation day to 3 weeks. Blood and fecal samples were examined. Two calves with a haptoglobin concentration of >500 µg/ml on day 0 were excluded from the experiment, and 10 calves were finally included. Glucose and vitamin A levels on day 7 were significantly higher (P less then 0.05) in the supplement group than in the control group. No significant differences were observed in haptoglobin or serum amyloid A between the groups. The number of Escherichia coli in feces was lower in the control group than in the supplement group on day 21 (P=0.06). No difference was observed in the number of bifidobacteria, but that of lactic acid bacteria was significantly higher (P less then 0.05) in the supplement group on day 21. The number of medications administered was significantly lower (P less then 0.05) in the supplement group (5.2 ± 3.9) than in the control group (10.6 ± 5.9) during the experimental period. The results indicated that HK-LS HS-1 is potentially beneficial for improving intestinal microbes and reducing the number of medical treatments.Some radiologic patient positioning techniques that can be used for X-ray examinations can be difficult to apply. One method involves using ultra-low-dose X-ray images to confirm positioning. These positioning images are typically discarded and not used for diagnosis. The purpose of this study was to improve the signal-to-noise ratio (SNR) in diagnostic imaging by including these ultra-low-dose positioning images rather than discarding them. To add two images together, we devised a method in which one image is multiplied by the coefficient calculated from its SNR before the addition. The images were dichotomized into a high SNR group and a low SNR group. The images in the high SNR group and the low SNR group were summed. When doing so, the images of the low SNR group were multiplied. There was one maximum SNR point while the SNR was being changed. The maximum SNR of the synthesized images was equal to the value of the square root of the sum of the squares of the two images. The multiplication coefficient, in the case of the maximum SNR, was near 1 when an image agreed with the Poisson distribution; when it did not, it was far from 1. The difference between the calculated values of the hypothetical measurement of the multiplication coefficient was small. In this study, we showed that improving SNR of a diagnostic image could be achieved by adding a positioning image. The multiplication coefficient in the case of the SNR maximum of a synthesized image is calculable. The measurement of a Wiener spectrum is needed for noise evaluation. There can be problems where there is motion after a positioning image is exposed.In recent years, the exposure dose of the operator’s eye lens during interventional radiology operations has become a problem. We therefore evaluated the feasibility of real-time lens dose measurement using scintillator with optical fiber (SOF) dosimeter. Given that the SOF dosimeter is calibrated for direct X-rays, we performed a calibration for scattered X-rays to investigate energy dependence and the accuracy of lens dose measurements. The detection limit was calculated using the Kaiser method. The SOF dosimeter and the radiophotoluminescence glass (RPLG) dosimeter were attached to the protective glasses worn by the operator, and the lens exposure dose of the operator during cardiac catheterization was measured. In the phantom experiment, the SOF dosimeter had an error rate of 5.45% based on the measured value of the ionization chamber dosimeter. The sensitivity characteristics of the SOF dosimeter were slightly reduced on the higher side of the effective energy. The difference in sensitivity was related to variations in the additional filter and energy dependency. The sensitivity difference was 18.5% at maximum. Furthermore, when the additional dose was displayed, the influence of noise on long-term measurement was considerable. Using the Kaiser method to obtain the detection limit, the accuracy of the integrated dose had SOF dosimeter error rates of 4.3% to 15.5% with respect to the integrated value of the RPLG dosimeter when calibrated by the ionization chamber dosimeter. The use of the SOF dosimeter allowed for the real-time visualization of the exposure status of the eye lens and measurements with a relatively high accuracy.
The purpose of this study was to improve the accuracy of dose-distribution calculations by understanding how the calculated dose varies with the change in the relative electron density replacing polymethyl methacrylate (PMMA) in patient-specific quality assurance.
We calculated the relative electron density at which dose attenuation in each dose calculation algorithm coincides with the measured value of the dose attenuation of single-field irradiation. Next, the dose change was calculated by changing the relative electron density or physical electron density for substituting PMMA for each X-ray energy and calculation algorithm. Furthermore, using clinical plans, changes in point-dose verification and dose-distribution verification that occurred when the relative electron density or physical electron density was varied were investigated.
The dose attenuation varies depending on the dose-calculation algorithm, and the optimum value of the electron density is different for each. After the electron density optimization, the point dose verification using the 97.1% to 98.3% (3%/3 mm), 90.0% to 94.3% (2%/3 mm) and gained a dominant improvement tendency (P<0.001).
We clarified dose change accompanying relative electron density or physical electron density change. We concluded that the accuracy of dose-distribution calculation for verification improves by replacing PMMA with optimal relative electron density or physical electron density.
We clarified dose change accompanying relative electron density or physical electron density change. We concluded that the accuracy of dose-distribution calculation for verification improves by replacing PMMA with optimal relative electron density or physical electron density.
To compare the radiation dose and image quality using the conventional method for performing the front and side scout view and a new method for performing the side scout view, and then correct the table height at the scan isocenter and perform the front scout view.
We retrospectively analyzed fifty-six children who had underwent computed tomography (CT) examination between June 2014 and August 2018. We divided them into two groups. The conventional method was performed in 3 steps 1. obtain the front scout view, 2. obtain the side scout view, and 3. main scan. Without table position correction, the new method was performed in 4 steps 1. obtain the side scout view with table position correction, 2. patient correction at the scan isocenter, 3. obtain the front scout view, and 4. main scan. We used a 64-row CT scanner (LightSpeed VCT; GE Healthcare). Scan parameters were tube voltage 80 kV, automatic tube current modulation, noise index 16, slice thickness 5 mm, rotation time 0.4 s/rot, helical pitch 1.375, ahis potential new method (1. obtain the side scout view, 2. patient correction at the scan isocenter, 3. obtain the side scout view, and 4. main scan).
This phantom study aimed to determine the optimal acquisition window size for phase-based respiratory gating in silicon photomultiplier (SiPM)-based fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and its acquisition time in respiratory-gated imaging with the optimal window size.
Images of a moving NEMA IEC Body Phantom Set
with hot spheres were acquired. First, the tumor volume and the maximum standardized uptake value (SUV
) of images reconstructed using a different window size were evaluated to define the optimal window size. Second, the quality of the images reconstructed using the optimal window size and different acquisition times was evaluated using the detectability score of the 10-mm hot sphere and physical indices.
The volume and the SUV
of the 10-mm hot sphere were improved when the window size was narrow, and there were no significant differences among images reconstructed using a window size narrower than 20%. To reconstruct an image using the 20% window size, an acquisition time of 5 min was required to visualize the 10-mm hot sphere.
The optimal window size for phase-based respiratory gating is 20%. Further, an acquisition time of 5 min should be taken for respiratory-gated imaging with the 20% window size on SiPM-based FDG-PET/CT.
The optimal window size for phase-based respiratory gating is 20%. Further, an acquisition time of 5 min should be taken for respiratory-gated imaging with the 20% window size on SiPM-based FDG-PET/CT.The purpose of this study was to investigate the trends of researches regarding radiological technology. We collected research papers published from 2007 to 2017 from Japanese Society of Radiological Technology (JSRT). After preprocessing, we performed morphological analysis using terminology from Japan Radiological Society, Japan Society of Medical Physics, and JSRT to extract technical terms. Furthermore, we calculated the Jaccard similarity coefficient to represent the similarity between two terms. This value ranged from 0 to 1, where 0 implied that the terms were completely dissimilar. Finally, in order to detect terms that characteristically appear in each year, we visualized co-occurring terms by using network diagrams. From the morphological analysis, 5471 technical terms were extracted. The most frequency term was „image” from 2007 to 2017. „Phantom” and „CT” were frequent terms after „image.” In addition, the number of research papers including „image,” „phantom,” and „CT” were increasing. For network analysis, the characteristic terms in 2007 were „filter” and „HU”; those in 2012 were „dimension,” „standard deviation,”and „artifact”; and those in 2017 were „PET,” „scattered ray,” and „collimator.” In conclusion, the highest interest research topic in radiological technology was „image,” and recently, there has been a tendency to be interested in topics related to nuclear medicine.Amiodarone is an effective antiarrhythmic drug. However, it is associated with changes in thyroid function in euthyroid patients due to its high iodine content and intrinsic drug effects. Studies have been conducted in iodine-deficient and iodine-sufficient countries; however, data from countries with excessive iodine intake are lacking. Thus, this study aimed to evaluate the effect of long-term amiodarone treatment on thyroid function in euthyroid Japanese patients. Japanese adults aged ≥18 years who were treated with amiodarone for at least 90 consecutive days were included in this retrospective chart review. Patients with abnormal thyroid function test results at baseline were excluded. Serial changes in thyroid function tests at baseline and at days 30, 90, 180, 270, and 360 were analyzed using a mixed-effects model for repeated measures. In total, 46 patients with a mean age of 63.7 years were evaluated. The mean TSH level significantly increased from 1.62 μIU/mL at baseline to 3.43, 2.75, 2.84, 2.78, and 2.


