To confirm the performance improvement of virtual monoenergetic images (VMIs) for iodine contrast tasks in a clinical photon-counting detector CT (PCD CT) using Fourier-based assessment, compared with those in the latest-generation dual-source dual-energy CT (DECT). A water-filled bath with a diameter of 300 mm, which contains rod-shaped phantoms equivalent to diluted iodine (2 and 12 mg/mL), was scanned using PCD CT and DECT at 15, 7.5, and 3 mGy.
View Article and Find Full Text PDFPrompt gammas imaging (PGI) is a promising method for observing a beam's shape and estimating the range of the beam from outside a subject. However 2-dimensional images of prompt gammas (PGs) during irradiation of protons were still difficult to measure. To achieve PGI, we developed a new gamma camera and imaged PGs while irradiating a phantom by proton beams.
View Article and Find Full Text PDFBackground and objective Although early diuretic use and negative fluid balance (NFB) have been associated with lower mortality in mechanically ventilated patients, some patients are not tolerant to NFB. Little is known about whether urine output response after the diuretic administration predicts NFB tolerance in mechanically ventilated patients. Hence, we conducted this study to look into this.
View Article and Find Full Text PDFThis research aimed to identify materials capable of emitting visible light useful for dose management at ultra-high dose rate (uHDR). Various materials were irradiated with proton beams at a normal dose rate (NDR) and uHDR, and the resulting surface luminescence was captured using a high-sensitivity camera. The luminescence images were compared with the corresponding dose distributions.
View Article and Find Full Text PDFTransanal total mesorectal excision (taTME) has improved the laparoscopic dissection for rectal cancer in the narrow pelvis. Although taTME has more clinical benefits than laparoscopic surgery, such as a better view of the distal rectum and direct determination of distal resection margin, an intraoperative urethral injury could occur in excision ta-TME. This study aimed to determine the feasibility and efficacy of the ta-TME with IRIS U kit surgery.
View Article and Find Full Text PDFWe elucidate the decomposition mechanism of hydrogen peroxide, which is formed by water radiolysis, by gold nanoparticles (GNPs) under X-ray irradiation. The variations in yields of hydrogen peroxide generated in the presence of GNPs are evaluated using the Ghormley technique. The increase of yields of OH radicals has been quantified using Ampliflu® Red solutions.
View Article and Find Full Text PDFHigh-resolution and real-time imaging of particle ion trajectories is essential in nuclear medicine and nuclear engineering. One potential method to achieve high-resolution real-time trajectory imaging of particle ions involves utilizing an imaging system that integrates a scintillator plate with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera. However, acquiring an EM-CCD camera might prove challenging due to the discontinuation of CCD sensor manufacturing by vendors.
View Article and Find Full Text PDFHigh sensitivity and high resolution is desired in such technologies as neutron radiography. However, the contamination of gamma photons in neutron images decreases the accuracy of neutron radiography. To solve this problem, we developed an event-by-event based neutron imaging system that can selectively detect neutrons.
View Article and Find Full Text PDFObjectives: This study aimed to examine the association between ABCDEF bundles and long-term postintensive care syndrome (PICS)-related outcomes.
Design: Secondary analysis of the J-PICS study.
Setting: This study was simultaneously conducted in 14 centers and 16 ICUs in Japan between April 1, 2019, and September 30, 2019.
Introduction And Importance: Lateral lymph node dissection (LLND) for recurrent lateral pelvic lymph node metastasis could be the only surgical treatment to improve its prognosis, but is difficult and challenging technically.
Case Presentation: A 75-year-old Japanese man who underwent a radical laparoscopic intersphincteric resection to treat double lower rectal cancer. Computed tomography and MRI showed lower rectal wall thickening and bilateral lateral lymph node swelling.
Recently, in-beam positron emission tomography (PET) has been actively researched for reducing biological washout effects and dose monitoring during irradiation. However, the positron distribution does not precisely reflect the dose distribution since positron production and ionization are completely different physical processes. Thus, a novel in-beam system was proposed to determine proton dose range by measuring scattered protons with dozens of scintillation detectors surrounding the body surface.
View Article and Find Full Text PDFFLASH radiation therapy with ultrahigh dose rates (UHDR) has the potential to reduce damage to normal tissue while maintaining anti-tumor efficacy. However, rapid and precise dose distribution measurements remain difficult for FLASH radiation therapy with proton beams. To solve this problem, we performed luminescence imaging of water following irradiation by a UHDR proton beam captured using a charge-coupled device camera.
View Article and Find Full Text PDFPrompt x-ray imaging is a promising method for observing the beam shape from outside a subject. However, its distribution is different from dose distribution, and thus a comparison with the dose is required. Meanwhile, luminescence imaging of water is a possible method for imaging the dose distribution.
View Article and Find Full Text PDF. Prompt x-ray imaging using a low-energy x-ray camera is a promising method for observing a proton beam's shape from outside the subject. Furthermore, imaging of positrons produced by nuclear reactions with protons is a possible method for observing the beam shape.
View Article and Find Full Text PDFHigh-resolution imaging of alpha particles is required in the detection of alpha radionuclides in cells or small organs for the development of radio-compounds for targeted alpha-particle therapy or other purposes. We developed an ultrahigh resolution, real time alpha-particle imaging system for observing the trajectories of alpha particles in a scintillator. The developed system is based on a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera, combined with a 100-µm-thick Ce-doped GdAlGaO (GAGG) scintillator plate.
View Article and Find Full Text PDFPrompt secondary electron bremsstrahlung X-ray (prompt X-ray) imaging using a low-energy X-ray camera is a promising method for observing a beam shape from outside the subject. However, such imaging has so far been conducted only for pencil beams without a multi-leaf collimator (MLC). The use of spread-out Bragg peak (SOBP) with an MLC may increase the scattered prompt gamma photons and decrease the contrast of the images of prompt X-rays.
View Article and Find Full Text PDFIntroduction: and importance: TEP might be one of options for treating such a sports hernia.
Case Presentation: An 18-year-old Japanese male presented with right groin pain for approximately two years. The pain was initially felt on the right side only, especially on kicking.
Purpose: Although real-time imaging of the high-activity iridium-192 (Ir-192) source position during high-dose-rate (HDR) brachytherapy using a high-energy gamma camera system is a promising approach, the energy window was not optimized for spatial resolution or scatter fraction.
Methods: By using a list-mode data-acquisition system that can acquire energy information of a cerium-doped yttrium aluminum perovskite (YA1O: YAP(Ce)) gamma camera, we tried to optimize the energy window's setting to improve the spatial resolution and reduce scatter fraction.
Results: The spatial resolution was highest for the central energy of the window at ∼300 keV.
The prevalence of burnout among critical care professionals during the coronavirus disease (COVID-19) pandemic varies in different countries. To investigate the prevalence of burnout and turnover intention in Japanese critical care professionals in March 2021. This cross-sectional study used a web-based survey of Japanese critical care professionals working in 15 intensive care units in 15 prefectures.
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