[Purposes] In 2005, criteria for diagnosing the metabolic syndrome was officially announced. Accumulation of fat tissue in and around the abdomen is one of the metabolic syndrome. To assess the excess fat tissue, the waist circumference is measured. Computed tomography can work out the area of the intra-abdominal fat tissue. In this study, we examined exposure conditions with a view to reducing dose and radiation risk.[Methods] A CT phantom model simulating the abdominal area at the level of the umbilicus was made for obtaining the pictures of the intra-abdominal fat tissue with the tube current ranging from 10 mA to 250 mA set at intervals of 10 mA. The average CT value for the area of mimic fat tissue obtained by each scan and standard deviations were worked out.[Results] The size of fat tissue and the mean CT value were constant with a tube current of 100 mA or over. [Conclusions] It was found possible to measure the area of intra-abdominal fat tissue with a tube current of 100 mA. Therefore, our findings showed that the radiation exposure could be reduced by 60% when compared with the 250 mA CT used at a clinical setting.
Adipose tissue ; X-Ray Computed Tomography ; mA ; Radiation ; Accident due to exposure to weather conditions

The removal of aspiration objects is often required for aspiration, which takes place at the time of a video fluoroscopic examination of swallowing (VF) for the assessment of dysphagia rehabilitation. We report our approach against correspondence for aspiration at VF.　　As subjects for this report, we sampled 6 patients (average age: 78.3±3.0, four males and two females) from 19 patients, who had aspiration of barium sulfate or meal with barium contrast medium at the time of VF form October 1, 2009, to March 31, 2011. For the first step of correspondence for aspiration at VF, we dealt with coughing, huffing, suction and postural drainage under the guidance of a Speech-Language-Hearing Therapist and, depending on the case, a Physical Therapist who dealt with chest physical therapy. When expectoration was found impossible, we checked to see if it was necessary to perform biphasic cuirass ventilation with a clinical engineer. We assessed the chest X-ray films and existence or non-existence of expectoration immediately after aspiration, and fever, inflammatory response, respiratory symptoms and gastrointestinal symptoms one week after the examination, and retrospectively checked the influence of aspiration.　　As a result, three patients had residue as revealed on chest X-ray films, and the three remaining patients had none. For the former three patients, we intervened in a team approach and succeeded in removing the residue from two patients (one with initial correspondence, and the other with execution by the Physical Therapist). Though two patients had fever and inflammatory response one week later, It was hardly possible that aspiration at the time of VF became a direct cause. No patient had either the respiratory or gastrointestinal symptom.　　Correspondence for aspiration was attained by establishing a team approach system. Even if a patient had heavy aspiration, it was not reflected on chest X-ray films, depending on the case, and therefore deliberation was required for correspondence.