[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

Accidents involving metals brought into the MRI room are occurring with increasing frequency. The Japan Council for Quality Health Care has released medical safety information about bringing magnetic materials into the MRI room, showing that this is an important safety issue. In our hospital, there were 4 accidents involving metal brought into the MRI room between April 2012 and March 2016. One serious incident was a projectile accident involving scissors carried by a nurse. In response, we have adopted new preventive measures, including specialized uniforms and a color-coding scheme for indicating MRI-safe and MRI-unsafe items (using colored tape, etc.). Here we report on the effect of these accident prevention efforts.