Nihon Hoshasen Gijutsu Gakkai Zasshi
May 2024
Purpose: In X-ray computed tomography (CT), noise distribution within images is nonuniform and thought to vary with imaging conditions. This study aimed to evaluate noise nonuniformity by altering specific imaging conditions, such as tube voltage, bow-tie filter (BTF), and phantom size.
Methods: Using four tube voltages (80, 100, 120, and 135 kV), two BTF types (L and M), and circular water phantoms with diameters of 240, 320, and 400 mm, we employed filtered back projection (FBP) for reconstruction.
Nihon Hoshasen Gijutsu Gakkai Zasshi
October 2023
Purpose: Although breast compression has been an efficient practice to reduce the breast dose in mammography, there may be some differences between analog and digital systems. The purpose of this study was to evaluate the dose-reduction efficiency by breast compression in digital mammography under its own criterion that signal difference-to-noise ratio (SDNR) be kept at a certain value.
Method: By adopting SDNR as an image quality indicator and average glandular dose (AGD) as a dose indicator, we measured SDNR versus AGD relationship for each breast depth.
The effective focal spot size of x-ray tubes is one of the major factors that substantially affect the resultant x-ray images, and it is known to be dependent on the x-ray exposure setting used. This study aims to evaluate the relationship between the effective focal spot size and the tube current and voltage and assess its reproducibility among several x-ray tubes. The evaluation was performed using edge response analysis, in which a 1-mm thick tungsten edge was projected onto a flat panel detector with a magnification factor of 2.
View Article and Find Full Text PDFAn 80-year-old woman who visited our hospital with chief complaints of decreased appetite and diarrhea. Lower gastrointestinal endoscopy showed a type 2 tumor in the rectal Ra, and biopsy revealed a well-differentiated adenocarcinoma. The patient had locally advanced rectal cancer with widespread contact with the sacrum, and preoperative radiochemotherapy (S-1 100 mg/day plus radiotherapy 50 Gy/25 Fr)was performed.
View Article and Find Full Text PDFFor the focal spot measurement of x-ray tubes, we propose a practical method in which only a metal edge and a digital detector are used, together with a process of removing detector blur inherently associated. The evaluation was made through the optical transfer function (OTF) measurements using the edge response of a 1-mm-thick tungsten plate. First, we made the acquisition of a geometrically magnified edge response, which consists of focal spot penumbra and detector blur, followed by the acquisition of nonmagnified edge response, which includes only detector blur.
View Article and Find Full Text PDFIn the original publication of the article, the figures were published in wrong order.
View Article and Find Full Text PDFRelapsing polychondritis is a rare multi-system disease characterized by inflammation in cartilaginous structures and other connective tissues. Cardiovascular complications occur in 10-51% of the patients. We report a case of concomitant aortic valve replacement, mitral valve replacement, and coronary artery bypass grafting in a patient with relapsing polychondritis.
View Article and Find Full Text PDFObjective: This study aimed to evaluate the outcomes of mitral valve (MV) repair versus MV replacement with preservation of the entire subvalvular apparatus.
Methods: We retrospectively searched our dedicated in-hospital database for patients who underwent MV surgery between 2012 and 2017.
Results: A total of 82 patients were divided into a group that underwent MV replacement (n = 35) and a group that underwent MV repair (n = 47).
Nihon Hoshasen Gijutsu Gakkai Zasshi
February 2017
Japanese Society of Radiological Technology (JSRT) standard digital image database contains many useful cases of chest X-ray images, and has been used in many state-of-the-art researches. However, the pixel values of all the images are simply digitized as relative density values by utilizing a scanned film digitizer. As a result, the pixel values are completely different from the standardized display system input value of digital imaging and communications in medicine (DICOM), called presentation value (P-value), which can maintain a visual consistency when observing images using different display luminance.
View Article and Find Full Text PDFNihon Hoshasen Gijutsu Gakkai Zasshi
March 2016
Fifty posterior-anterior chest radiographs taken using an auto exposure control were evaluated in order to find an optimum determination method of the exposure index (EI). Four types of the relevant image regions were tested: (a) full image, (b) central 25% area, (c) full image excluding direct x-ray area, and (d) pulmonary area only, whereas four types of the value of interest (VOI) were adopted to each relevant image region: mean, median, mode, and middle. When the target EI was determined as the average of the 50 images, the deviation index (DI) was within ±1.
View Article and Find Full Text PDFThe purpose of this study was to evaluate the diagnostic capability of gadoxetate disodium (Gd-EOB)-MRI for the detection of hepatocellular carcinoma (HCC) compared with multidetector CT (MDCT). Fifty patients with 57 surgically proven HCCs who underwent Gd-EOB-MRI and MDCT from March 2008 to June 2011 were evaluated. Two observers evaluated MR and CT on a lesion-by-lesion basis.
View Article and Find Full Text PDFThe liverwort, Porella vernicosa complex produces a very hot tasting polygodial, a drimane-type sesquiterpene dialdehyde. The same compound has been isolated from two ferns, Thelypteris hispidula and Blechnum fluviatile, as well as from the higher plants Polygonum hydropiper, P. hydropiper f.
View Article and Find Full Text PDFThe mechanisms regulating stem cell differentiation and self-renewal are largely unknown. Our ultimate goal is to be able to regulate somatic stem cell differentiation and proliferation. In the present study the ability of trans-differentiation was studied when different normal tissue types were transplanted into the duodenum in rats.
View Article and Find Full Text PDFIt is clinically important to diagnose diabetic neuropathy at the early stage. In this study, the toneentropy analysis of electrocardiogram was applied to diabetic patients to evaluate its usability in the screening of diabetic neuropathy. Consecutive 102 diabetic patients were invited to the study.
View Article and Find Full Text PDFA real-time digital filter for noise reduction in X-ray images is proposed. The filter is based on averaging of only similar pixels (pixels that differ only little) rather than neighboring pixels, which are averaged in conventional linear low-pass filters. The effectiveness of the filter was evaluated by computer simulation, where original images that were acquired by X-ray exposure were processed in accordance with the filter algorithm.
View Article and Find Full Text PDFWe report an autopsied case of a 74-year-old man with primary pulmonary squamous cell carcinoma (SCC) associated with leukocytosis, hypercalcemia, phagocytosis in the bone marrow, reactive lymphadenopathy and mesangial cell proliferation in the glomerulus. Laboratory examination revealed increased serum levels of parathyroid hormone-related peptide (PTH-rP), granulocyte colony stimulating factor (G-CSF), interleukin-6 (IL-6) and soluble interleukin 2 receptor (s-IL2R). An autopsy showed moderately differentiated SCC at the left lower lobe of the lung, of which tumor cells distinctly showed cytoplasmic immunoreactivity to anti-G-CSF and anti-PTH-rP antibodies.
View Article and Find Full Text PDFClin Exp Nephrol
December 2007
A 20-year-old Japanese woman was admitted to a hospital because of gross hematuria. She was diagnosed with IgA nephropathy with a poor prognosis, based on the formation of many crescents in the glomerulus and monocyte infiltration in the interstitium in a renal biopsy specimen in February 2003. Myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA) was not identified at that time.
View Article and Find Full Text PDFWhile organ-specific stem cells with roles in tissue injury repair have been documented, their pathogenic significance in diseases and the factors potentially responsible for their activation remain largely unclear. In the present study, heart, kidney, brain, and skin samples from F344 transgenic rats carrying the GFP gene were transplanted into normal F344 rat liver one day after an intraperitoneal injection (i.p.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
October 2005
Biphenol was shown to bind dihydrogenphosphate (H2PO4-) selectively over various other anions (MeCO2-, Cl-, Br-, I-, NO3-, HSO4-). The highly selectivity of biphenol toward dihydrogenphosphate is explained in terms of the basicity and shape of the guest anion.
View Article and Find Full Text PDFThirty-three patients with type 2 diabetes mellitus (16 men, 17 women) were divided into 3 groups based on urinary excretion of albumin (U-Alb)--group A: U-Alb < 30 mg/d; group B: 30 mg/d < or = U-Alb < or = 300 mg/d; and group C: 300 mg/d < U-Alb. Serum creatinine levels were lower than 2.0 mg/dL in all the subjects.
View Article and Find Full Text PDFCell differentiation is very important but not well understood. In the present study the ability of various tissues to newly-differentiate when transplanted into the fundus or the duodenum in rats was tested. Pieces of esophagus, bladder, diaphragm and trachea from 8-week-old male F344 rats were transplanted into the gastric fundus or duodenum of females and examined after 3 or 6 months.
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