Objective: Our aim was to evaluate image quality and radiation dose of screening CT colonography (CTC) conducted by the fixed tube current technique or that using an automatic tube current modulation system.
Subjects and Methods: Screening CTC at 3 fixed tube current settings (group A,50 mAs; group B,75 mAs; and group C,100 mAs) and that with an automatic tube current modulation system (group D, Volume EC SD20) using a 64-channel MDCT scanner were performed on 836 asymptomatic individuals. In addition, all groups were divided into 4 subgroups based on differences in body mass index (BMI). The mean radiation dose of each group was determined using the dose-length product. Image quality was evaluated by 3 independent reviewers.
Results: The mean radiation dose was 10.7 mSv for group A, 16.0 mSv for group B, 20.7 mSv for group C, and 5.4 mSv for group D. Thus, the radiation dose was lower in the group scanned using the automatic tube current modulation system (Volume EC SD20) than in the groups scanned by the fixed tube current technique (50 mAs, 75 mAs, or 100 mAs). The overall radiation dose increased as BMI increased, especially in group D. All subjects in all groups had acceptable image quality.
Conclusions: The results of this study show that the radiation dose during CTC can be reduced by an automatic tube current modulation system while maintaining diagnostic image quality. An appropriate automatic tube current modulation system is therefore useful for screening CTC.

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Objective: Our objective was to clarify the limitations of screening mammography (MMG) conducted at our facility by comparing the findings for breast cancer not detected by medical check-up MMG (non-detected cancer by screening MMG) with those for MMG from an institution conducting more detailed medical examinations (diagnostic MMG).
Methods: From January 2007 to December 2011, among 90 cases of cancer not detected by medical check-up MMG in combination with ultrasound screening (US) at our facility, 36 were non-detected cancer by screening MMG. Based on the findings for these 36 cases, we compared the characteristics of non-detected cancer by screening MMG and non-detected cancer by diagnostic MMG.
Results: Over half of the 36 cases of non-detected cancer by screening MMG were also not detected by diagnostic MMG. However, through additional bi-planar, magnified and spot-compressed MMG, cancerous lesions were detectable. Ductal carcinoma in situ (DCIS) with no calcification and infiltrating tumors of less than 10 mm in diameter tended to go undetected.
Conclusion: Our findings suggested that the detection capacity of MMG was limited. In this regard, we observed a tendency for non-infiltrating cancer, small diameter cancer and cancer with very little infiltration to go undetected. We therefore consider that MMG screening should be conducted in combination with US to improve detection rates.

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Objective: We analyzed similarities in lifestyle and lifestyle-related diseases in married couples living together.
Methods: Our subjects were 570 married couples aged between 40 and 74 years who visited our center from April 2008 to March 2012. Husbands and wives were divided into 3 groups each according to the number of unhealthy habits in 6 daily behavior categories (exercise, breakfast, eating between meals, sleeping, smoking, drinking) they had. Age, Body Mass Index (BMI), waist circumference, weight change and frequency of lifestyle-related diseases were compared among the 3 groups. We also compared another 3 groups composed of the corresponding spouses of the males and females classified into the 3 groups above. Furthermore, concordance between husband and wife was evaluated by odds ratios.
Results: The more unhealthy habits a person had, the greater his (her) weight, waist circumference and frequency of lifestyle-related diseases. Similar results were obtained in the corresponding spouse groups. Thus, the more unhealthy habits someone had, the more unhealthy habits their spouse had too. When a husband had an unhealthy lifestyle, the odds ratios for his spouse to have an unhealthy lifestyle were more than 2 in all 6 daily behavior categories. Odds ratios were higher for the group of husbands over 60 years old than for those under 60.
Conclusions: Our study suggests that the lifestyles of married couples are closely related and similar. To provide health check-up examinees with effective health guidance, health check-up institution staff should be aware of the potential influences between husband and wife and recommend them to take health consultations together.

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Objective: As mild leukocytosis is discovered occasionally in health check-ups, we investigated cases of mild leukocytosis detected during health check-ups at our hospital in 2011．
Methods: Thirteen of 2,182 persons who underwent a health check-up at our hospital in 2011 were considered to have leukocytosis as their white blood cell count was more than 10,000/μl. We investigated its causes. Among the 13 subjects, there were 2 with leukemia.
Case Report: A 54-year-old woman developed a sore throat and felt feverish a few days before the health check-up. She was diagnosed with tonsillitis by a local doctor, who prescribed antibiotics. She had recovered by the time of the health check-up. The laboratory tests conducted in the health check-up revealed slight leukocytosis (13,000/μl) and mild liver dysfunction. In a more detailed examination, a blood smear contained 2.0% myelocytes and 3.0% metamyelocytes, and considering the fact that that the subject had just recovered from an infection, we followed her up. As basophils also began to increase, a blood disorder was suspected and she was diagnosed with CML through further examination.
Results: The suspected cause of leukocytosis in 6 subjects was smoking, that in 4 was transient infection, that in 1 was unknown and that in 2 was leukemia, one of whom was the subject described above (total 0.1%).
Conclusions: Even in cases of slight elevation of white blood cell count, leukocytosis should be suspected. It is important to investigate the causes of leukocytosis, and provide follow-up.

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Objective: Evidence for the effectiveness of PET medical examinations (PET dock) is still insufficient. To improve the quality of this type of examination, active management that encourages patients with abnormal findings to receive consultation and subjects them to follow-up surveys is necessary. We present some of the strategies employed in our hospital for this purpose.
Methods: We investigated 2,116 subjects who underwent our PET cancer dock from April 2006 to March 2012. Detailed examinations had been recommended for those in whom cancer was suspected. We examined whether there were changes in response rates after encouraging them to receive consultation.
Results: We received responses by letter or telephone from medical facilities for 183 of the 2,116 subjects and cancer was noted in 33 (1.6%) of them. The 2006-2008 response and cancer detection rates were 32% and 0.9%, respectively. However, with active management from 2009 onwards, these rates rose to 74% and 1.9%, respectively. The following post-examination management strategies were followed. Immediately after the examination, the doctor explained the results, and if there were abnormalities, consulted the most appropriate medical facilities. The doctor sent a report together with a CD-R of the PET images. When there was no reply from the respective medical facilities, the doctor again mailed an inquiry.
Conclusion: In our efforts to improve the quality of cancer screening by PET medical examinations, it is important to consider the overall results. It is necessary to not only report any abnormalities but also to provide optimal management after examinations.

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Objective: Although the evidence suggests a relationship between nephrolithiasis and lifestyle-related diseases, few large-scale studies have been conducted in this regard in Japan. We therefore examined a relationship between lifestyle-related factors and nephrolithiasis in health check-up examinees.
Methods: In 35,647 persons who underwent health check-ups for the first time between November 2003 and December 2011, we examined associations between nephrolithiasis and BMI, systolic and diastolic blood pressures, triglycerides, total, HDL and LDL cholesterol, fasting blood glucose, HbA1c, uric acid, drinking, smoking, exercise and presence of renal calcification by univariate and multivariate analysis. We also examined associations between numbers of metabolic syndrome risk factors or presence of nephrolithiasis and presence of calcification.
Results: In univariate analysis, a significant association with nephrolithiasis was observed for BMI, systolic and diastolic blood pressures, triglycerides, total and LDL cholesterol, fasting blood glucose, uric acid, drinking, smoking, and presence of renal calcification. In multivariate analysis, a significant association was noted for gender, age, calcification, diastolic blood pressure and uric acid, but in an analysis in which the effects of age, gender and calcification were eliminated, significance was only observed for diastolic blood pressure. Regarding numbers of metabolic syndrome factors, the frequencies of 1, 2 and 3 factors were greater in a “nephrolithiasis group” than in a “no nephrolithiasis group”. Regarding presence of calcification and nephrolithiasis, the percentage of 2 factors+3 factors increased in the order “not either”, “calcification only”, “nephrolithiasis only”, “both calcification and nephrolithiasis”
Conclusion: While univariate analysis indicated that most lifestyle-related factors were associated with nephrolithiasis, multivariate analysis revealed that there was only an association with diastolic blood pressure. Our findings suggested the possibility that progression of metabolic syndrome and nephrolithiasis are associated and that calcification is a precursor to nephrolithiasis.

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Objective: Fatty liver is considered to be an aspect of metabolic syndrome and is frequently associated with hypertension. However, it has not been established that fatty liver causes hypertension. The purpose of the present study was to determine the relationship between fatty liver and occurrence of hypertension in subjects with normal blood pressure.
Methods: 1,088 men with normal blood pressure were studied. They were divided into 2 groups: non-fatty liver group (874 men) and fatty liver group (214 men). The prevalence of hypertension was compared between the groups after a 10-year follow- up period. Each group was further divided into 2 subgroups, according to presence or absence of fatty liver after 10 years, for which the prevalence of hypertension was compared. In the non-fatty liver group, the relationship between fatty liver and occurrence of hypertension was studied.
Results: The occurrence of hypertension in the 10-year longitudinal study was higher in the fatty liver group, compared to the non-fatty liver group. In the 4 subgroups, subjects with fatty liver at the end of the study were more hypertensive, compared to those without fatty liver. However, fatty liver was not found to be an independent risk factor of hypertension after adjustment for factors that may influence the occurrence of hypertension.
Conclusion: Fatty liver was frequently associated with hypertension. However, it was not an independent risk factor for hypertension.

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Objective: Detection of postprandial hyperglycemia in the early stage of diabetes mellitus is crucial. However, the indices used during routine health check-ups are relatively insensitive to glucose intolerance in the early stage. The aim of this study was to evaluate the effectiveness of our newly developed method for measuring glucose area under curve (AUC) without blood sampling after test meal loading.
Methods: Fifty volunteers who had not been previously diagnosed with diabetes were asked to consume a test meal (75 g of carbohydrates) during a routine health check-up. The glucose AUC monitoring system was applied 2 h after meal loading. In addition, capillary blood glucose was measured 1 and 2 h after meal loading to obtain reference values. Urinary myoinositol and other indices of glucose intolerance were also measured before and/or after meal loading.
Results: Glucose AUC measurements using our system were well correlated with capillary blood glucose measurements (r = 0.85). Compared with urinary myoinositol measurement, that with our system was better (sensitivity 73%, specificity 84%) at distinguishing glucose intolerance characterized by elevated blood glucose from normal glucose tolerance.
Conclusion: We demonstrated that our glucose AUC measurement system that screens for glucose intolerance after test meal loading is convenient and painless. Furthermore, the use of this system with test meals would be effective in screening for glucose intolerance during a routine health check-up.

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Objective: Hepatocellular carcinoma usually arises from viral hepatitis and in many cases is discovered in routine outpatient exams. However, it is also sometimes first discovered in health check-ups (ningen dock). In the present study, we examined cases of hepatocellular carcinoma discovered in abdominal ultrasonography during ningen dock at the health check-up center of our hospital.
Methods: Our subjects were 107,652 persons (65,499 males, 42,153 females; age 18 - 90 yrs., average age 48.8 yrs.) who underwent abdominal ultrasonography at our health check-up center from 2000 - 2010.
Results: During the above period, 1,543 subjects were positive for HBs antigens (1.43% of total) and 713 were positive for HCV antibodies (0.66%). Hepatocellular carcinoma was discovered in 6 subjects, all of whom were male. Excluding an elderly subject of 77 yrs., the average age was 53.6 yrs. (age range 49 - 59 yrs.). The underlying disease was hepatitis C in 1 subject and hepatitis B in 5 subjects. Regarding lifestyle history, all 6 were drinkers and 4 were smokers. In blood biochemistry results, ZIT was abnormal in more subjects than AST or ALT. From albumin values and platelet counts, hepatic reserve was predicted to be favorable. The tumors noted ranged from 6 - 27 mm in size (average 14 mm). Regarding treatment, 2 subjects underwent radio wave diathermy and 4 surgical resection.
Conclusion: Chronic inflammation is present in many health check-up examinees who are positive for hepatitis virus markers, though AST, ALT and platelet counts are within the normal ranges. Therefore, they should be strongly advised to undergo examination at a medical institution specializing in this area. We feel that the early discovery of hepatocellular carcinoma in health check-ups is very important because it provides a good opportunity to select a therapy with a high chance of effecting a cure.

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Objective: In order to provide a high quality service in which the various types of radiological testing performed during health check-ups are conducted safely, preventing the occurrence of incidents and accidents in such testing is extremely important. We investigated the causes of X-ray room-related incidents and accidents as well as strategies to prevent their recurrence. We also looked at the important points to consider when conducting radiological testing during health check-ups and examinations.
Methods: We conducted a data search of the Japan Council for Quality Health Care (JCQHC) website for X-ray room-related incidents and accidents. From the summary reports on them, we investigated their causes and recurrence prevention strategies.
Results: A search of the JCQHC website using the keyword “X-ray room” revealed 65 instances of incidents or accidents. Twelve instances were before testing, 14 during testing and 39 after testing. The effects on patients ranged from minor to serious. They were reported by radiologists, physicians, nurses and other healthcare professionals.
Conclusions: As the performance of radiological testing involves many different healthcare professionals, it may not be easy to prevent the recurrence of X-ray room-related incidents and accidents through the efforts of a single specialty team or an individual. Our findings suggested that the development of a collaborative multidisciplinary prevention system for incidents and accidents is necessary to ensure a safe, high quality radiological testing service in health check-ups.

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Objective: Some are of the opinion that curable lung cancer cannot be detected by conventional direct chest radiography (chest radiography) and that CT must be used to discover it. Despite this, we report the discovery of 6 cases of lung cancer through chest radiography in 1,395 examinees. This demonstrates the importance of attitude in radiograph interpretation.
Methods: Subjects were 1,395 persons with no respiratory symptoms who were examined in the Ningen Dock and General Internal Medicine Outpatient Departments of our hospital over an 18-month period beginning in March 2009. They were examined and had their radiographs interpreted by the author himself.
Results: Among 45 patients in whom lung cancer was suspected or could not be ruled out on the basis of chest radiographs, definitive diagnoses of lung cancer (including carcinoids) were made as a result of further detailed examinations or surgery at our hospital in 6 patients. Four of them had Stage IA cancer.
Conclusion: Through being completely focused, paying great attention to detail and tenacity in observation, we achieved a discovery rate of 0.4% for lung cancer using chest radiographs.

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