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We retrospectively investigated the success rate of pulmonary arteriovenous separation in a single-phase computed tomography (CT) protocol using the estimated time of arrival (ETA) method. A total of 223 patients who underwent a single-phase CT protocol using the ETA method for pulmonary arteriovenous separation were included in the analysis. Dual source CT (SOMATOM Force, SIEMENS) was used for imaging. The tube voltage was 80 kVp, and the scan mode was turbo flash spiral mode. CT values of main pulmonary artery (MPA), peripheral pulmonary artery (pPA), peripheral pulmonary vein (pPV), left atrium (LA), ascending aorta (AAo) and descending aorta (DAo) were measured. When the difference in CT values on the central side was 100 Hounsfield unit (HU) or more, it was judged that the separation was successful. The mean CT values were 671.9±154 HU for MPA, 424.4±81.2 HU for LA, 551.1±142.6 HU for pPA, 351.6±94.0 HU for pPV, 362.2±75.8 HU for AAo, and 282.7±83.7 HU for DAo. The mean difference in CT values of the pulmonary artery and vein was 247.5±138.9 HU on the central side and 199.5±133.0 HU on the peripheral side. There were 90.1% of cases where the difference in CT values on the central side was 100 HU or more. In addition, a strong positive correlation (r=0.849, p<0.001) was found between the CT value of MPA and the CT value difference on the central side. The success rate of pulmonary arteriovenous separation by the ETA method, which is a method that enables stable pulmonary arteriovenous separation, was 90.1%.

The restlessness of young children often causes motion artifacts on CT images. We devised a new animation projector system (CT Theater) that enables a child to view an animation during a pediatric head CT examination. The purpose of this study is to assess the usefulness on a children of a video viewed during a head CT scan. Children of 3-10 years old who underwent head CT (SOMATOM Definition Flash, SOMATOM Force; Siemens) were analyzed for a period from 6 months before, to 6 months after, introduction of the projector system (before: n=46, after: n=29). Mobile projector (MP-CL1; Sony) connected with tablet device (iPad; Apple) was put on the CT table near the child's head. An animation was projected on the child's line of sight inside the gantry. The animation is projected on the line of sight of the child such that the projector moves with the child on the table. The number of requests for use made by children was 28/29 (96.6%). The presence of images without motion artifacts decreased significantly after introduction (before/after introduction: 84.8% vs 100%, p=0.03). The overall examination success rate tended to increase after introduction (84.8% vs 92.9%, p=0.26). The overall examination time was significantly reduced (92.4±42.4 s vs 65.1±47.3 s, p<0.001). We developed an animation projector system that shortened examination time and decreased motion artifacts in pediatric head CT.

We have developed an estimated time of arrival (ETA) method as a new single-phase scan for pulmonary artery/vein separation. This method enables differentiation of CT values between arteries and veins by means of two-step consecutive injection of contrast medium based on the pulmonary circulation time. This paper presents an overview of the ETA method and scan technique. Since the ETA method is a single-phase scan, it uses a low radiation dose compared with the conventional multi-phase scan. Moreover, this method eliminates gaps due to breath holding. The ETA method can detect irregularities and obtain high-quality pulmonary artery/vein separation 3D-CT images.

Objectives: Our purpose was to clarify the situation regarding blood pressure control through awareness of hypertension among female groups of in-home caregivers and non-caregivers., Methods: We used one existing data generated between December 2005 and April 2007. The subjects were females who were suffering from hypertension (66 caregivers were aged 49-84 years; 52 non-caregivers were aged 47-81 years). We defined persons suffering from hypertension on the basis of results of a self-administered questionnaire and blood pressure values. On the question of awareness of hypertension, we defined the persons who replied positively to any one of "I have hypertension," "I have suffered from hypertension," or "I take antihypertensive agents" as belonging to the "awareness group." We categorized the other respondents, who replied to all three questions in the negative as belonging to the "non-awareness group." We used blood pressure values, to build an index of the control with the chi2 test and the t-test for statistical comparisons. Values of P < 0.05 were considered statistically significant., Results: The results showed that blood pressure values of caregivers in both the awareness group and the non-awareness group were high (awareness group vs non-awareness group overall SBP: 148 +/- 20 mmHg vs 154 +/- 9 mmHg, DBP: 79 +/- 13 mmHg vs 82 +/- 10 mmHg, P > 0.05). Furthermore, values were significantly lower for the awareness than non-awareness group with respect to the non-caregivers (SBP: 135 +/- 15 mmHg vs 149 +/- 7 mmHg, DBP: 73 +/- 10 mmHg vs 78 +/- 6 mmHg). Caregivers who took the antihypertensive agent in the awareness group demonstrated high values exceeding SBP 140 mmHg, which was the hypertensive standard value, not different from the values for caregivers not taking such medication. (taking vs non-taking SBP: 148 +/- 21 mmHg vs 149 +/- 8 mmHg)., Conclusion: Among the caregivers, it was not only the members of the non-awareness group but also those of the awareness group who were found to have high blood pressure values. Though the caregivers took antihypertensive agents, their blood pressure values remained high.

The aim of this study was to investigate the relationship between partial electrical reset (PER) and CT scan parameters (tube voltage, tube current, rotation time, and product of tube current and rotation time in mAs). A cardiac resynchronization therapy pacemaker (Insync 8040, Medtronic Inc., Tokyo) and 320 area detector CT scanner (Aquilion ONE, Toshiba medical systems, Otawara, Japan) with volume scan were used. The pacemaker was put in DDD mode. The PERs were interpreted using both the programmer's wave forms and error messages. The exposure was repeated 5 times per CT setting. The pacemaker was placed on the anterior wall and upper side of a chest phantom. Each CT scan was performed using the following parameters: tube voltage of 80, 100, 120, and 135 kV; tube current of 50-550 mA; and rotation time of 0.35-1.5 s. PERs were observed at 100, 120, and 135 kV, and more PERs were observed as the tube voltage increased. The PER tube current decreased as the rotation time was increased. In contrast, the PER tube current and rotation time product (mAs) increased as the rotation time was increased. More specifically, the radiation dose rate was the affected factor of the PERs. To avoid PER of pacemakers, CT scan parameters with lower radiation dose rates (low rather than high tube current and rotational time) is recommended. In conclusion, our results will help with CT scans of patients who have implantable cardiac devices (included pacemakers and cardioverter defibrillators).

For convenience of outpatients, mammographies of outpatients are often taken after the injection of a radionuclide. In this study, we investigated the effects of gamma rays emitted by a patient onto imaging plates (IPs). We used a flat container filled with (99m)Tc solution as a planar source to irradiate gamma rays onto IPs. We changed irradiation times on each IP, and took radiographies of an ACR-specified 156 model phantom and AGH-D210F phantom. We evaluated radiography images, using visual evaluation, and profile curves, histograms, and CNR and RMS granularities analyses. The results indicated that the depiction ability of a fibrous part began to fall when the irradiation time exceeded 3 minutes. With an increase in irradiation time, an increase in pixel value and RMS granularity value and a decrease in CNR value were observed. In conclusion, IP exposed by gamma rays influenced the evaluation of phantom images.

A 56-year-old woman was admitted to our hospital with fever, cough, and sputum production. Her chest radiograph and chest computed tomography showed multiple nodules. Laboratory findings revealed leukocytosis and an increased C-reactive protein concentration. Physical examination revealed a systolic murmur. Transesophageal echocardiography demonstrated a 1.5-cm area of vegetation on the tricuspid valve. Blood cultures grew Staphylococcus aureus. Tricuspid valve endocarditis and septic pulmonary embolism were diagnosed. She was treated successfully with intravenous ampicillin/sulbactam. This was a rare case of tricuspid valve infective endocarditis in an adult patient without known predisposing factors.

A 53-yr-old man with a history of chronic renal failure was admitted to the hospital of Hyogo College of Medicine on March 24th, 1999, because of severe continuous hemoptysis. On February 14th, 1999, the patient had undergone a cadaveric kidney transplantation in the urology department of another hospital. He did not experience any immunological reactions due to tissue rejection. On admission, subcutaneous bleeding at the site of an injection received 1 month before was noticed on his left arm. Petecheae of the extremities and a conjunctival hemorrhage were also noted. However, coagulation and fibrinolysis tests were essentially normal. These findings indicated that the hemorrhages were due to vessel weakness. Scurvy was diagnosed since his serum vitamin C was extremely low (0.2 microgram/ml). The patient was given ascorbic acid (1 g/day), and his condition improved dramatically. Ten years ago, the patient had had renal failure, which had been treated with chronic maintenance dialysis and dietary restriction. It has been postulated that a diet lacking in vitamin C or the steroid treatment he received after kidney transplantation may have induced the scurvy.

A 60-year-old man was admitted to our hospital complaining of progressive dyspnea. On admission, he had marked hypoxemia, and his chest radiography and computed tomography (CT) showed ground glass opacities and multiple emphysematous changes in both lung fields. On examining the patient's bronchoalveolar lavage fluid (BALF). Pneumocystis carinii pneumonia (PCP) was diagnosed. A serological test for human immunodeficiency virus (HIV)-1, 2 was positive, and acquired immunodeficiency syndrome (AIDS) was diagnosed. Since the chest CT performed a month before the patient's admission to our hospital revealed ground glass opacities in both lung fields we thought that he had already developed PCP at that time. In comparison with his previous CT, the chest CT on admission showed progressive ground glass opacities and emphysematous changes. Although PCP is known to display various findings on chest radiography and CT, emphysematous changes are rarely reported in Japan. In this case we were able to confirm these changes and observe its progression using chest CT.

On August 14, 2001, a 76-year-old woman with a history of rheumatoid arthritis was admitted to our hospital with fever, cough, dyspnea and diarrhea. On admission, her chest radiography showed pleural effusion on the right side, and thoracocentesis was used to diagnose empyema. The patient underwent pleural drainage and received antibiotics. Alpha-Streptococcus was detected in both aerobic and anaerobic cultures of the pleural effusion. After 2 weeks of therapy, her empyema had improved; but her diarrhea, which had started 1 week before admission, had worsened, and her hypoproteinemia had progressed. Examination of the fecal clearance of alpha-1-antitrypsin and biopsied rectal material revealed that the diarrhea was caused by protein-losing enteropathy due to gastrointestinal amyloidosis secondary to rheumatoid arthritis. The patient was treated with steroids, but developed an additional infectious disease and died on September 29, 2001. In this case, she suffered from various infectious diseases including empyema and fungus infections. It has been reported that protein-losing enteropathy accompanies abnormalities in the immune system, by the loss of immunoglobulins and lymphocytes from the gut. We therefore suspect that protein-losing enteropathy due to gastrointestinal amyloidosis caused this patient's empyema.

On November 15, 2000, a 60-year-old man was admitted to our hospital with progressive dyspnea and right chest pain. He had a 40-year history of occupational asbestos exposure, which began when he was 20 years old. On admission, his chest radiographs showed pleural effusion on the right side, and asbestos bodies were detected in his sputum. Neither a cytological examination of the pleural effusion nor a histological examination of the pleura by percutaneous pleural biopsy revealed malignant cells. In addition, we could not find any other cause for the pleural effusion (such as tuberculosis, collagen disease, or heart failure). In May 2001, the patient also developed pleural thickening and pain in the right hypochondrium, and he was readmitted to our hospital on May 21, 2001. On readmission, an enhanced abdominal CT showed multiple liver tumors, and percutaneous pleural and liver biopsies were performed. The histological findings in the pleura and liver specimens revealed hypocellular collagen tissues without malignant cells. Thus, we could not determine the main cause either of the pleural effusion or of the patient's disease. However, his condition rapidly deteriorated, and he died on August 12, 2001. At the autopsy, bilateral pleural thickening, predominantly on the right side, and invasion of the lungs were observed. The histological findings in the pleural and hepatic tissues revealed hypocellular collagen fibers with a striate pattern and areas of neoplastic spindle cells. He was diagnosed as having malignant desmoplastic mesothelioma with liver metastasis. Cases of malignant desmoplastic mesothelioma have rarely been reported in Japan.

A 51-year-old male, who had been driving a motor bicycle, was involved in a traffic accident with a trailer, and he died immediately after the accident. According to the external examination of the victim, no fatal injuries were found. The medico-legal autopsy revealed a rupture of the left side of the pericardium, and a tear of the posterior leaflet of the mitral valve. There were no injuries of the papillary muscles and chordae. The cause of death was due to traumatic mitral regurgitation.