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Estimating the average glandular dose (AGD) from a mammographic exam is essential for assessing radiation-induced cancer risk. In this study, we propose Mdec-Toki Monte Carlo Method with the aim of visualizing the dose distribution of the entire breast under different arbitrary glandularities, compressed thicknesses, and exposure parameters and evaluating the absorbed dose at an arbitrary point. A phantom with 50% glandularity values was used for the optically stimulated luminescence (OSL) dosimeters measurements to obtain the percentage depth dose PDD from the incident surface to the emission surface. Using the Mdec-Toki method under the same settings as those used for actual measurements and PDD was used to calculate the AGD. The PDD and AGD at an arbitrary point, obtained from Mdec-Toki method simulations and the actual measurements using OSL were similar. The proposed method may be adapted to individual patients and can support radiation safety management during mammography.

This study aimed to investigate the feasibility of estimating functional ischemia information from coronary artery computed tomography (CACT) data (i.e., morphological information). Fifty-five suspected ischemic heart disease patients were included in this study. To calculate the ischemic myocardium percentage (LV myocardial territories volume of distal portion the stenotic lesion/total LV myocardial volume) from CACT data with "coronary territories analysis, Ziostation2", and compared with the ischemic LV myocardium percentage and the functional flow reserve (FFR). The results showed that ischemic LV myocardium percentage was correlated with the FFR (r=-0.57). The median ischemic LV myocardium percentage of the FFR-positive group (n=33) was 37.1% (interquartile range [IQR] 33, 41.4%) and that of the FFR-negative group (n=22) was 24.8% (IQR 19.6, 30.6%). The ischemic LV myocardium percentage was significantly higher in the FFR-positive group (p0.01) than in the FFR-negative group. The receiver operating characteristic (ROC) curve showed that the cutoff value for the ischemic LV myocardium percentage was 30%, with the sensitivity of 90.9% and the specificity of 77.3%. In conclusion, myocardial ischemia to diagnosis of FFR may occur when ischemic LV myocardium percentage is over than 30% and is unlikely to occur when it is less than 30%. This study suggests that the analysis of CACT data may contribute to the diagnosis of functional ischemia.

Developing a multilayered structure of adjective words that explains semantic relationships between human perceptual and affective responses to stimuli is instrumental in the design of affective aspects of products. However, the determination of multilayered structure is demanding and, thus far, it has been conducted by experienced developers in a trial-and-error manner. This study developed a method to systematically establish such structures through common tasks for sensory evaluation where products are rated along adjective labels. This method gradually expands the model from a simple two-layered to complex multilayered structures until it is accepted by structural equation modeling. The lower and higher layers of the initial two-layered model are composed of sensory and affective adjectives, respectively. The parts with weak fit indices of the higher layer are then remodeled, resulting in a multilayered affective structure. To validate the method, we built adjective structures based on responses to touching plastic plates. The method resulted in three- and four-layered structures that were quantitatively and semantically valid.

The purpose of this study was to educate operators regarding cardiac catheterization using radiation protection slides prepared for this study and to consider whether or not this radiation protection education contributes to reducing the exposure of the operator's ocular lens. Thermoluminescent dosimeter (TLD) was installed at the outside left, inside left, outside right, and inside right of the X-ray protective eyewear of the operators performing the cardiac catheterization. The exposure dose rate before and after radiation protection education for 3 operators performing cardiac catheterization was compared. The exposure dose ratio was defined by dividing the TLD measurement value, which is the air kerma calculated by the X-ray diagnosis apparatus for the angiography. In other words, this can calculate the ratio of how much the operators are exposed to radiation from the dose of the patient per examination. When comparing the radiation dose ratio obtained from the dosimeter installed on the right outer side before and after education, p-value was

Objectives The efficacy of radiotherapy for breast cancer has greatly improved owing to better irradiation methods. Radiotherapy aims to deliver therapeutic doses to predetermined target volumes while sparing surrounding healthy tissues. However, there are few reports on radiation exposure to eye lenses, and the recommended exposure limits to ocular lens have been substantially reduced in recent years. This study aimed to investigate the amount of radiation exposure to eye lenses using optically stimulated luminescence dosimeters (OSLDs) and determine whether wearing special protective devices to protect the eyes, as an organ at risk, during whole breast irradiation, is necessary. Methods This experiment used OSLDs on water‐equivalent phantom to measure the change in scattered radiation dose due to the difference of irradiation field while using 4‐ and 6‐MV photons of TrueBeam linear accelerator. Using a total treatment dose of 50 Gy, a target was positioned to approximate the breast, and a plan was formulated to deliver 2 Gy per treatment by tangential irradiation. The mean (SD) irradiation dose at the lens position outside the irradiation field was reported. Results The scattered radiation dose outside the irradiation field was more affected by the irradiation field size than by the radiation energy. The out‐of‐field irradiation dose with a larger field of view was higher than that with a smaller field of view. The use of 0.07‐ and 0.83‐mm‐thick lead shield protective glasses reduced the radiation dose by 56.1% (P

During computed tomography (CT) examinations, it may be necessary to assist the patient to maintain an appropriate body position. However, there is little protective equipment available for caregivers who approach the gantry. This study aimed to evaluate the effectiveness of novel radiation protective curtains in reducing radiation exposure to caregivers while assisting patients, especially during CT examinations of the head.The absorbed dose in air around the gantry during CT examinations of the head was measured using glass dosimeters. The measurement points from the center of the gantry were 40 to 120 cm in the front, 0 to 100 cm for each side in the right and left, and 60 to 180 cm from the floor. Measurements were performed at each 20-cm interval, and all points were accumulated 10 times. The absorbed dose in air in a CT room was compared with and without the protective curtains. Next, we assumed the height of the caregiver to be 170 cm, and measured the points for the crystalline lens, chest, and abdomen. Also, using the protective glasses and the protective apron, we measured the absorbed dose in air for the caregivers behind the protective curtains.The absorbed exposure dose in air toward the crystalline lenses, chest, and abdomen was reduced more than 90% by using the protective curtains and more than 95% by using the protective apron and protective glasses in addition to them.This study showed the usefulness of protective curtains in reducing the absorbed exposure dose in air to caregivers.

The visibility of moving images during cardiac catheterization and treatment may be reduced by a number of factors. First, it involves multiple movements that occur simultaneously, such as the movements due to the heart beat and movement of the guide wire used during the treatment. There is also the influence of the X-ray dose on the image quality in the X-ray output. If X-rays are irradiated onto moving objects such as a guide wire moving during treatment of the heart, cardiac catheterization may be displaced to the next image recorded even when an insufficient X-ray dose has been irradiated because the imaged object is moving during the time the X-rays are emitted (pulse width). If the X-ray dose planned to be irradiated to the target is low, there is also the possibility that noise will appear in the image, and the imaged object may be lost in noise and visibility be reduced. For this reason, we conducted basic research into how changes in the speed of rotation of guide wires affect visibility when wires are positioned horizontally and vertically, using a dynamic phantom and recorded X-ray moving images. The purpose of this study is to elucidate whether the deterioration in the visibility is affected by the X-ray dose, the orientation or movement of a guide wire, or caused by other conditions, in order to contribute to improving the visibility in the X-ray moving images. The results showed a lower visual evaluation only in the vertical direction at the more rapid movement here, but this did not result in significant changes in the physical evaluation. This suggests that the structure and characteristics of the human eyes would be involved, as human vision is stronger with lateral movements and weaker with vertical movements due to the arrangement of the human eyes, side by side. Findings from this basic study can be utilized to improve the visibility in the X-ray moving images by paying attention to the observation environment of the observer of the X-ray moving images. In addition, the findings of this study can also be used to determine protocols for improving visibility in X-ray moving images, such as adjusting the X-ray dose in an X-ray device when further improvement is required. Therefore, this study was able to provide suggestions to contribute to the development of improved visibility of X-ray moving images.

In coronary angiography (CAG) and percutaneous coronary intervention (PCI), it is important for radiological technologists to optimize the balance between radiation dose and image quality for physicians to be able to perform CAG and PCI most effectively. Evaluation of image processing is necessary to ensure that technologists can optimally adjust image quality for clinical use to the extent that physicians require. However, few phantoms are available for evaluating fluoroscopic image processing, and this makes it necessary to adjust image quality in clinical settings while utilizing the image processing according to the manufacturer’s recommendations. In this study, we developed a dynamic phantom that mimics a pulsating coronary artery for use in image quality analysis of moving images. We also examined whether processed images (image lag) can be physically analyzed. Two issues require special attention in creating a new phantom: establishing the exact position of the simulated blood vessel in the phantom, and providing good reproducibility. The study used the rotational motion of a disk to generate images, with a circular simulated blood vessel on the rotating acrylic disk, with the center of the simulated blood vessel shifted from the center of the acrylic disk. This enabled the reproduction of translational motion of the simulated blood vessel. As a result, because this phantom has signals and afterimages at the same position (of a simulated blood vessel), a quantitative evaluation of the afterimages became possible. In the evaluation of the image processing with the angiograph, it was shown that evaluations of image lag which are typically performed in clinical settings can be performed with the dynamic blood vessel phantom.

The quality of the present day fluoroscopic images is sufficiently high for use as exposure images depending on the environment where the fluoroscopic images are recorded. In some facilities which use fluoroscopic images as exposure images they are recorded with a radiological x‐ray diagnostic device equipped with a fluoroscopic storage function. There are, however, cases where fluoroscopic images cannot be used as exposure images because the quality of the fluoroscopic image cannot be assured in the environment where the fluoroscopic images are recorded. This poses problems when stored fluoroscopic images are used in place of exposure images without any clearly established standard. In the present study, we establish that stored fluoroscopic images can be used as exposure images by using gray values obtained from profile curves. This study finds that replacement of stored fluoroscopic images with exposure images requires 20.1 or higher gray scale value differences between the background and signal, using a 20 cm thick acrylic phantom (here an adult abdomen as representing the human body) as the specific geometry. This suggests the conclusion that the gray value can be considered a useful index when using stored fluoroscopic images as exposure images.

Background: Fractional flow reserve (FFR) is used to evaluate the need for percutaneous coronary intervention (PCI) in cases of moderate stenosis of the coronary artery. Recently, diagnostic imaging support with computational fluid dynamics (CFD) analysis has been garnering attention. This study defines the relationship between FFR conducted for cardiac catheterization and CFD analyses conducted using coronary computed tomography (CT) for moderate stenosis, in addition to considering whether wall pressure (WP) and wall shear stress (WSS) can be used to evaluate ischemia. Methods and Results: Cases in which FFR was measured via coronary CT and cardiac catheterization was performed within 3 months were collected retrospectively. In the CFD analysis, WP and WSS were calculated and compared with FFR. Three groups were created to compare results of CFD analysis and FFR values according to the location of the stenosis: the right coronary artery, the left anterior descending artery, and the left circumflex artery. There was a correlation between FFR and WSS according to CFD analysis for moderate stenosis of the coronary artery, with a cut-off value for treatment able to be calculated. Conclusions: The results of this study suggest that ischemia can be evaluated by conducting CFD analysis (WSS) using coronary CT.

Introduction Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined. Methods We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT. Results We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy. Conclusion By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.

In recent years, reports have been made that predict the state of aneurysm by performing computational fluid dynamics (CFD) analysis using cerebral aneurysm blood flow analysis software. However, analysis results are not constant and there are various opinions, and it is conceivable that the image quality and analysis conditions of medical images used for CFD analysis are not standardized. In this study, CFD analysis of cerebral aneurysm phantom was performed, and image quality and analysis conditions were standardized. Then, we investigated whether increase of cerebral aneurysm and prediction of rupture are possible. From this study, stable results of wall shear stress analysis were obtained under slice thickness 1.0 mm or less, CT value 400 HU or more, reconstruction function as soft part function, image SD under 10 HU. In addition, as the size of the cerebral aneurysm became larger, wall shear stress tended to be lower, and the same tendency was shown also in clinical cases. Although CFD analysis using software dedicated to blood flow analysis did not reach the prediction of rupture, it can be evaluated based on the quantitative values for the aneurysm increase at the preceding stage and plays an important role in prediction there is a possibility.

In this study, computer simulations and experiments were used to verify the accuracy of a two-dimensional image registration program (program) for portal images that we previously developed. The program used a computed radiography cassette system and digitally reconstructed radiography images as planning images for external beam radiation therapy. Using this program, we also investigated the reason two-dimensional automatic image registration images experienced large misregistration in clinical practice using commercial image registration systems. Mutual information and normalized mutual information were used as the registration criteria. To investigate the influence of image background with or without a region of interest (ROI), results of image registrations were compared. Parameters of image registration were defined as translation in the horizontal and vertical directions (x and y, respectively) and rotation (θ) around the axis perpendicular to the x-y plane. There was no significant difference in image registration arising from the difference between mutual information and normalized mutual information. Image registration was improved with a ROI. Regardless of the registration criteria, errors in image registration with a ROI in the experimental study were ≤1.2 mm in directions x and y and ≤1.0 degree in rotation θ. We found that image registration required setting up as close to the planned position as possible.

Following recent rapid advances in devices and treatment technology, indications for percutaneous peripheral intervention (PPI) have been expanded to include complex lesions (long-segment lesions, completely obstructed chronic lesions, etc.) and even lesions of the superficial femoral artery and arteries distal to the popliteal artery. However, when PPI is used for treatment of complete obstruction, treatment can take a long time or its outcome can be less satisfactory for reasons such as difficulty in assessing the vascular distribution/arrangement or the direction of calcification in the obstructed area or excessively long lesions. In the present study, we conducted three-dimensional image processing of CT data from leg arteries conventionally used for preoperative diagnosis. Using this processing technique, we created virtual images of the blood vessels of the completely obstructed area and mapped these virtual vessel images onto the fluoroscopic monitor image during catheter treatment. The usefulness of this technique for PPI was then evaluated. We succeeded in creating virtual vessel images of the completely obstructed parts of leg arteries with the use of preoperative CT images of leg arteries that we then mapped onto the fluoroscopic monitor images during treatment. We were successful in mapping virtual images onto the abdominal aorta in 96.8% of cases and in 95.7% with the common iliac artery. This technique is thus able to supply reliable information on vascular distribution/arrangement, suggesting that it can enable the surgeon to advance the treatment device precisely along the vessels, making it useful for treatment with PPI. The study additionally showed that differences in the angle of imaging affect the manual mapping of the CT images onto angiograms.

In this study we analyzed the influence of region of interest (ROI) selection on the uptake ratio of the liver to the liver plus heart at 15 min (LHL15) during (99m)Tc-galactosyl human serum albumin (GSA) scintigraphy and determined the optimal ROI by evaluating the individual effects of different ROIs in the heart on LHL15. Twenty patients were randomly selected from those who had undergone (99m)Tc-GSA scintigraphy GSA between April 2008 and June 2009. The liver body (L/B) ratio, liver uptake 15 min (LU15), and LHL15 were analyzed and compared among the following ROIs: entire heart, both ventricles, right ventricle, and left ventricle. There were significant differences in the L/B ratio and LU15 values among the different ROIs. However, LHL15 showed a tendency to shift toward a normal value when the size of the ROI was small (only the right or left ventricle), resulting in a lack of distinction between normal and abnormal LHL15 values. Furthermore, setting the entire heart as the ROI was difficult and reproducibility was low. Our results suggest that the use of both ventricles as the ROI provides optimal LHL15 values during (99m)Tc-GSA scintigraphy.

Purpose In this report, we evaluated whether radiological technologists' (RTs') awareness of patient safety would improve and what kind of effects would be seen at the department of radiological technology by introducing KYT [K: kiken (hazard), Y: yochi (prediction), T: (training)]. Methods KYT was carried out by ten RTs based on a KYT sheet for the department of radiological technology. To evaluate the effects of KYT, we asked nine questions each to ten participants before and after KYT enforcement with regard to their attitude to patient safety and to operating procedures for working safely. Results Significant improvements after KYT enforcement were obtained in two items concerning medical safety: It is important for any risk to be considered by more than one person; The interest in preventive measures against medical accident degree conducted now) and one concerning operating procedures (It is necessary to have a nurse assist during testing with the mobile X-ray apparatus) (p Conclusions Performing KYT resulted in improved awareness of the importance of patient safety. KYT also enabled medical staffers to evaluate objectively whether the medical safety measures currently performed would be effective for patients.

Background: Infliximab (IFX) is effective for remission induction and maintenance of Crohn's disease (CD). This trial assessed the efficacy of scheduled maintenance IFX monotherapy to prevent postoperative CD recurrence. Methods: Thirty-one CD patients who had ileocolic resection within the past 4 weeks were randomly assigned to scheduled IFX at 5 mg/kg intravenously every 8 weeks for 36 months (n = 15) or without IFX (control, n = 16). All patients were treated without immunomodulator or corticosteroid following surgery. The primary and secondary endpoints were remission rates at 12 and 36 months, defined as CD Activity Index (CDAI) ≤150, an International Organization for the Study of Inflammatory Bowel Disease (IOIBD) score

Changing into slippers when entering the nuclear medicine management district prevented pollution expansion. Accidents involving patients falling occurred in university facilities. It was thought that changing slippers was the cause. The pollution situation was measured in three facilities by using the smear method and the direct technique to examine the effect of changing slippers. The current state was measured. After pollution prevention guidance was continuously done, pollution expansion was measured; three weeks of measurements were compared. Pollution was detected in the first period of weeks at a frequency of 19 times. For the latter period, it was detected 6 times. Half the pollution was in the restroom. Pollution was reduced by doing pollution prevention guidance for the restroom. Patients' falls occur even if they change slippers. Falling accidents can be decreased.

Background: Leukocytapheresis (LCAP) is used as an adjunct therapy for patients with active ulcerative colitis (UC). Although, LCAP is routinely performed at 3,000 mL per session, we were interested to see that if this can be replaced with bodyweight (BW) adjusted volume. Methods: In an open label prospective trial, the clinical response to BW adjusted LCAP (BWA-LCAP) was evaluated in 14 patients with active UC. Fourteen demography matched UC patients who had been treated with the routine 3,000 mL LCAP were randomly sampled from our database as a control group. All patients were given 10 weekly LCAP sessions. In the BWA-LCAP group, the processed blood volume (PBV) was set at 30 mL/kg × BW/session. Baseline demographic measures were not significantly different between the two groups. Results: The average PBV in the BWA-LCAP group was 1971.0 ± 330.0 mL, range 1,020–2,460. In both groups, the average UC clinical disease activity index, the endoscopic index, and the concomitant prednisolone dosage were significantly and equally reduced during the course of 10 LCAP. Accordingly, at the end of the trial, no significant difference was seen in any outcome measure between the two groups. However, a significantly higher incidence of adverse event (AE) was observed in the routine 3,000 mL LCAP group as compared with the BWA-LCAP group (P < 0.01). Conclusions: The outcomes of this investigation showed that the therapeutic efficacy of LCAP based on 30 mL/kg × BW is similar to the routine 3,000 mL per session LCAP. However, BWA-LCAP should be favored if one is to see the full potential of LCAP without AE. © 2011 Wiley Periodicals, Inc.

In Japan, adsorptive granulocyte/monocyte apheresis (GMA) is an approved treatment option in patients with active Crohn's disease (CD). However, there is inadequate knowledge regarding the mechanism(s) of therapeutic effects of this non-pharmacologic treatment strategy. Further, recently we have been interested in the regulatory T-cell (Treg) profile which has an essential immunoregulatory function. Thirteen CD patients were treated with a single GMA session. The mean CD activity index (CDAI) and duration of CD were 218.5 and 9.8 years, respectively. Eight healthy volunteers participated as a control group. From CD patients, whole blood was taken immediately before and after the GMA session directly from the GMA column inflow and outflow lines. Broad spectrum serum key cytokines and chemokines were measured by suspension-array and ELISA. At baseline, almost all assayed inflammatory cytokines were significantly elevated in CD patients. Treg-associated cytokines including IL-10 (P < 0.02) and transforming growth factor (TGF)-β1 (P < 0.03), were higher in the GMA column outflow vs. inflow. In contrast, the Th1/Th2 balance, defined as IFN-γ/IL-10 was lower during hemofiltration (P = 0.05), potentially due to an elevated IL-10 (P < 0.02) because an elevation of pro-inflammatory IFN-γ (Th1) was not observed at the GMA column outflow. A single GMA session had a significant impact on the Treg profile. Treg-related cytokines like IL-10 and TGF-β1 in the blood returning to the patients from the GMA column outflow were elevated, while pro-inflammatory cytokines like IFN-γ were not. This action of GMA is potentially very interesting in patients with immune disorders, like CD patients.

Granulocyte/monocyte adsorption (GMA) has been introduced as an adjunct intervention for active ulcerative colitis (UC) patients. The processed blood volume (PV) per GMA session is an important factor for its efficacy because depletion of elevated/activated myeloid leukocytes is its main action. Hitherto, this aspect of GMA has been largely ignored. Thirty-three patients were enrolled for remission induction therapy with five weekly GMA sessions at a standard PV of 1800 mL, regardless of patients' bodyweight (BW). The patients were divided into three groups: high (H)BW (≥ 65 kg, n = 11), 50 kg ≤ medium (M)BW < 65 kg (n = 12), and low (L)BW (≤ 50 kg, n = 10). UC clinical activity index (CAI) was according to Lichtiger, and the clinical efficacies were evaluated at both one week post 3(rd) GMA (Week 4) and one week post 5(th) GMA (Week 6). The average BW was 70.9 ± 6.2 kg in HBW, 55.8 ± 4.5 kg in MBW, and 46.8 ± 1.2 kg in LBW, indicating the mean PV/BW in the three groups being 25.6 ± 2.12, 32.5 ± 2.50, and 38.7 ± 1.0 (mL/kg, P < 0.05), respectively. The LBW group consisted of female patients only. Significant improvements of CAI were seen before treatment at either Week 4 or Week 6 in all groups. A significantly higher remission rate was achieved in the LBW (80.0%) vs. MBW (33.3%) or HBW (27.3%) at Week 6 (P < 0.03). According to this GMA evaluation, the lower-limit of optimum PV/kg should be higher than 38.7 mL/kg for its potential clinical efficacy to be significantly greater than the routine GMA method. Additional BW-oriented GMA studies in larger and gender controlled cohorts of patients should strengthen our findings.

†‡ § Background/Aims: Infliximab (IFX), an antibody to tumor necrosis factor, (TNF)-α has effi cacy in treating Crohn’s disease (CD). However, knowledge of the potential effects of IFX on patients’ immune profi les is lacking. The purpose of this study was to reveal the immunological effects of IFX. Methods: Twenty-two patients with a CD activity index (CDAI) of 194.2±92.9 and an average duration of disease of 3.26 months and 21 healthy controls were included. Patients were to have their fi rst IFX remission induction therapy with 3 infusions (5 mg/kg) at weeks 0, 2, and 6. Oral 5-aminosalicylic acid was the only ongoing medication in the patient population. Blood samples at baseline, 12 hours after the first infusion and at week 14 were labeled with anti-CD4/ CD25 antibodies for immunohistochemical measurement of regulatory T-cells (Treg). Serum cytokines and chemokines were measured by suspension array and ELISA. Results: CDAI signifi cantly decreased prior to the second IFX infusion (p

A hand hygiene behavior questionnaire and environmental survey were conducted regarding the mobile X-ray system used in the emergency room. As a result, among a total of 22 radiological technologists at this hospital who replied to the questionnaire, 18 wore disposable gloves when performing X-ray imaging using the mobile system. Among those 18, 11 were found to touch computed radiology (CR) consoles and HIS/RIS terminals while still wearing the gloves, thus creating the potential for spreading pathogens to other medical equipment and systems. According to the results of an environmental survey of the emergency imaging preparation room, the highest levels of bacteria were detected on CR consoles and HIS/RIS terminals. A possible reason for this is that these locations are not wiped down and cleaned as a part of routine cleaning and disinfection protocols, thus demonstrating the importance of cleaning and disinfection. Hand hygiene by medical personnel and appropriate cleaning and disinfecting of the working environment are important for preventing the spread of nosocomial infections. Radiological technologists are also required to take effective measures against infections in consideration of the high frequency of contact with both infected patients and patients susceptible to infections.

I-125 permanently implanted sealed-source radiotherapy is one of the treatments for early localized prostate carcinoma. In order to choose treatment parameters such as the number of implanted sources, accurately determining the volume of the prostate is vital for this type of therapy. We compared the usefulness of transrectal ultrasound (TRUS), computed tomography (CT), and magnetic resonance imaging (MRI) for preoperative stereometry of the prostate, and we further reviewed the utility of the MRI measurement. We performed prostate stereometry with TRUS, CT, and MRI in each of 45 patients who had provided informed consent. Taking TRUS stereometry as the standard, we computed the correlation of the MRI results with TRUS, and that of the CT results with TRUS, and found that MRI had a higher correlation.

The new type of coronary angiography(CAG)that uses 40 mm volumetric computed tomography(VCT)has great potential for cardiac disease. However, it is still necessary to be cognizant of exposure dose. We measured doses of CAG by both VCT and cardiovascular X-ray using a body phantom within 170 glass dosimeters. VCT protocols were 120 kV, 570 mA, and 0.35 sec/rot with and without the dose-reduction features(small cardiac X-ray beam filter and ECG mA modulation). The cardiovascular X-ray protocol was Auto(65 - 77 kV)kV, Auto(41 - 46 mA)mA, 5 secx11 shots+11 min fluoroscopy(minimum protocol for screening). VCT with and without the dose-reduction features has the same dose distribution, however, the dose-reduction features reduced the amount of dose by about 40-50%. For VCT with those features, measured dose was about 70 mGy in the cardiac area and 60 mGy at the skin of the back, whereas those of cardiovascular X-ray were 10 mGy and 30 mGy. We measured detailed dose distributions and variations in the phantom, and we also demonstrated the possibility of VCT's dose-reduction features. The CT dose was still higher than that of cardiovascular X-ray, however, there were advantages of CT scanning, for instance, information about calcification, soft plaque, and 3D visualization. We think it is important to use both systems with an understanding of their advantages and limitations.

Background The removal of unwanted hair with various laser systems and related procedures has been investigated for many years. All researchers have met difficulty when trying to achieve "permanent" hair removal. In addition, damage to the epidermis and other complications, including hyper- or hypopigmentation in pigmented skin, have occurred because the laser energy was applied indirectly to the hair bulb through the epidermis. Objective To achieve permanent hair removal with the use of a diode-pumped neodymium:yttrium-aluminum-garnet laser system with an insulated optical needle. Also, to establish laser treatment parameters that allow for quick and effective removal of hair with minimal pain and no long-term medical complications. Method The laser used in the study was capable of producing up to 500 mJ of energy per burst at a 1,064-nm wavelength. A pulse width of 200-500 μs and a burst frequency of 100-200 Hz could be selected, and both defined a subset of the treatment parameter space. An optical needle, typically 130 μm in diameter, was prepared before each new treatment was conducted. Three bursts of energy, 300 mJ each, with a 300-millisecond interval, were delivered through the optical needle into each hair follicle. Between 200 and 300 shin hairs, typically terminal hairs, on each of 5 volunteers were treated. These volunteers were observed over 18.5-30 months for the regrowth of hairs by hair count. Results At the end of the observation period (6-30 months after the last treatment), 3 of 5 volunteers showed permanent loss of 76%-94.3% of their unwanted hair. One volunteer lost 34.8% of the original hair, but regrown hair was much thinner than the original terminal hair. One volunteer lost only 22.8% of the original hair, and regrown hair was coarse terminal hair. Except for the loss of hair, no change in skin texture, sensation, or skin color was observed. Conclusion The direct insertion optical method (DIOM), delivering laser energy directly to the hair bulb through an optical needle, has proven to be effective and achieves permanent hair removal in 60% of volunteers without medical complications.

This study aimed to evaluate the effect of a metal artifact reduction (MAR) algorithm using 1D linear interpolation on cone-beam CT (CBCT). We performed phantom and clinical qualitative studies with and without MAR application using 1D linear interpolation. In the phantom study, the standard deviation (SD) was estimated from the images obtained from the water phantom in which a metal coil was placed at the center, and observed the changes in the SDs before and after MAR application. In the clinical qualitative study, the clinical images after endovascular treatment (EVT) for cerebral aneurysms were visually evaluated before and after MAR application. In the phantom study, the SDs after MAR application decreased by 56 to 35% compared with that before MAR application. In the clinical qualitative study, the artifacts from the metal coil decreased or increased depending on locations, and the contrasts of gray matter and white matter were attenuated when MAR was applied. In conclusion, the metal artifact decreases when MAR using 1D linear interpolation is applied to cerebral CBCT. However, another artifacts increase or soft tissue contrast is changed in some cases. MAR largely contributes to the reduction of streaking artifacts, whereas it may induce cerebral parenchyma at distant metal body or quality deterioration of the image not including the metal body. This should be taken into account in the diagnosis of secondary hemorrhage or infarction.

Radiographic examination of the anterior part of the shoulder includes routine anterior-posterior imaging that enables easy visualization of traumatic injuries and true anterior-posterior imaging that enables the visualization of intra-articular injuries. The X-ray incident angle of true anterior-posterior imaging is affected by physique and posture. However, in many reports, the angle is uniformly determined on the basis of the antero-posterior axis and the horizontal plane. We previously reported that the glenohumeral joint can be visualized with good reproducibility by establishing a reference line on the basis of three points on the body as indicators, namely the posterior view of the under-surface of the acromion, the coracoid process, and the inferior angle of the scapula. However, visualizing the undersurface of the acromion using physical indicators to set the angle for imaging remains problematic. In previous reports, the angle was consistently set at 20° to the horizontal plane, regardless of physique or posture, which resulted in poor reproducibility. After examining the imaging techniques described in previous reports, we describe here an imaging technique using a reference line based on indicators on the surface of the scapula that enables the glenohumeral joint and the undersurface of the acromion to be visualized with good reproducibility.

The hamate bone, one of the carpal (wrist) bones, has a large uncinate process protruding from the palm side. In sports such as golf and tennis, the hamate bone can break if is subjected to a high external force, such as from the handle of a racquet or club. At our hospital we take X-ray images of the hamate bone from two directions: an axial image through the carpal tunnel and an image at the base of the hamate hook (conventional method). While the conventional method makes it easy to create images of the base of the hamate hook, the patient may suffer pain during image-taking because the hamate bone is pulled to cause radial flexion. We therefore investigated a method of imaging that would create three-dimensional computed tomography (3DCT) images of the base of the hamate hook in which the patient would only have to only rotate the wrist externally and elevate the fore-arm without any radial flexion. Our results suggest that it is possible to obtain images of the base of the hamate hook as clear as those acquired using the conventional method with the patient in a comfortable and painless position taking images at an external rotation angle of 50.3° and a forearm elevation angle of 20.3°.

We noted that breast-like artifacts occur in photo-stimulable phosphor plates (PSPs) used for long periods in digital mammography systems. This prompted us to investigate the effects on mammography diagnoses of these artifacts. Our study took the form of a comparison between the images generated by a long-term use PSP (four years use) and a short-term use PSP. First, an acrylic phantom and an in-house-made phantom for visual evaluation were imaged using X-ray PSPs under the same exposure conditions. They were then scanned under the same conditions to generate images. The mean values of the digital signals were measured in the 35 locations of region of interest present in the images of the acrylic phantom. The images of the in-house-made phantom were then visually evaluated by five certified experts, who examined 22 clinical images taken with both PSPs while referring to a visual evaluation scale. Differences were detected in all the evaluated items: the short-term use PSP gave a higher rate than the long-term use PSP (p

In interventional radiology, dose estimation using the interventional reference point (IRP) is a practical method for obtaining the real-time skin dose of a patient. However, the IRP is defined in terms of adult cardiovascular radiology and is not suitable for dosimetry of the head. In the present study, we defined a new reference point (neuro-IRP) for neuro-interventional procedures. The neuro-IRP was located on the central ray of the X-ray beam, 9 cm from the isocenter, toward the focal spot. To verify whether the neuro-IRP was accurate in dose estimation, we compared calculated doses at the neuro-IRP and actual measured doses at the surface of the head phantom for various directions of the X-ray projection. The resulting calculated doses were fairly consistent with actual measured doses, with the error in this estimation within approximately 15 %. These data suggest that dose estimation using the neuro-IRP for the head is valid.

Scapula-45 is an original roentogenographical technique to clarify objectively the function of the rotator cuff and scapulothoracic joint. This examination enables assessment of the function of the rotator cuff and scapulothoracic joint utilizing the radiographs of the glenohumeral joint. However, in the former technique, it was difficult for the technician to properly align the patient for the view of the true glenohumeral joint because of the individual postural difference of the patients, such as kyphosis. In the present study, we reported a new technique with the use of the acromion, coracoid process, and inferior angle of the scapula as a landmark to obtain the consistent radiographs of the glenohumeral joint.

In Japan, adsorptive granulocyte/monocyte apheresis (GMA) is an approved treatment option in patients with active Crohn's disease (CD). However, there is inadequate knowledge regarding the mechanism(s) of therapeutic effects of this non-pharmacologic treatment strategy. Further, recently we have been interested in the regulatory T-cell (Treg) profile which has an essential immunoregulatory function. Thirteen CD patients were treated with a single GMA session. The mean CD activity index (CDAI) and duration of CD were 218.5 and 9.8 years, respectively. Eight healthy volunteers participated as a control group. From CD patients, whole blood was taken immediately before and after the GMA session directly from the GMA column inflow and outflow lines. Broad spectrum serum key cytokines and chemokines were measured by suspension-array and ELISA. At baseline, almost all assayed inflammatory cytokines were significantly elevated in CD patients. Treg-associated cytokines including IL-10 (P0.02) and transforming growth factor (TGF)-β1 (P0.03), were higher in the GMA column outflow vs. inflow. In contrast, the Th1/Th2 balance, defined as IFN-γ/IL-10 was lower during hemofiltration (P = 0.05), potentially due to an elevated IL-10 (P0.02) because an elevation of pro-inflammatory IFN-γ (Th1) was not observed at the GMA column outflow. A single GMA session had a significant impact on the Treg profile. Treg-related cytokines like IL-10 and TGF-β1 in the blood returning to the patients from the GMA column outflow were elevated, while pro-inflammatory cytokines like IFN-γ were not. This action of GMA is potentially very interesting in patients with immune disorders, like CD patients.

Background Although CT urography (CTU) is widely used for the evaluation of the entire urinary tract, the most important drawback is the radiation exposure. Purpose To evaluate the effect of a noise reduction filter (NRF) using a phantom and to quantitatively and qualitatively compare excretory phase (EP) images using a low noise index (NI) with those using a high NI and postprocessing NRF (pNRF). Material and Methods Each NI value was defined for a slice thickness of 5 mm, and reconstructed images with a slice thickness of 1.25 mm were assessed. Sixty patients who were at high risk of developing bladder tumors (BT) were divided into two groups according to whether their EP images were obtained using an NI of 9.88 (29 patients; group A) or an NI of 20 and pNRF (31 patients; group B). The CT dose index volume (CTDIvol) and the contrast-to-noise ratio (CNR) of the bladder with respect to the anterior pelvic fat were compared in both groups. Qualitative assessment of the urinary bladder for image noise, sharpness, streak artifacts, homogeneity, and the conspicuity of polypoid or sessile-shaped BTs with a short-axis diameter greater than 10 mm was performed using a 3-point scale. Results The phantom study showed noise reduction of approximately 40% and 76% dose reduction between group A and group B. CTDIvol demonstrated a 73% reduction in group B (4.6 ± 1.1 mGy) compared with group A (16.9 ± 3.4 mGy). The CNR value was not significantly different ( P = 0.60) between group A (16.1 ± 5.1) and group B (16.6 ± 7.6). Although group A was superior ( P < 0.01) to group B with regard to image noise, other qualitative analyses did not show significant differences. Conclusion EP images using a high NI and pNRF were quantitatively and qualitatively comparable to those using a low NI, except with regard to image noise.