Atherosclerotic Progression Is Related to Immune-Related Adverse Events.

Immune checkpoint inhibitors (ICIs) are widely used in various types of cancers and patients. Recently, it has been reported that ICIs aggravate atherosclerosis. This study aimed to identify characteristics that are related to the progression of atherosclerosis.This study was conducted in a single medical center and included 32 patients who were grouped based on the presence of an immune-related adverse event (IRAE). There were 16 IRAE patients and 16 non-IRAE patients. Atherosclerosis was measured as the volume of calcified plaque at the aortic arch on a computed tomography (CT) scan. We measured the volume on CT at 3 time points as follows: before treatment, at ICI initiation, and after 180 days or more.After the first ICI administration, the IRAE group showed significant exacerbation of atherosclerosis compared to the non-IRAE group (P = 0.002). A high volume of plaque was observed in IRAE patients after ICI treatment as compared to before ICI administration (P = 0.058).ICIs tend to hasten atherosclerosis progression in IRAE patients, indicating that high-risk cardiovascular patients should be concerned about cardiovascular events. Moreover, this study suggests the possibility of predicting IRAEs based on the volume of calcified plaques.

Hemodialysis vascular access infection caused by Methylobacterium radiotolerans: The first confirmed case in Japan.

Methylobacterium species are heterotrophic and fastidious Gram-negative bacilli that can be opportunistic pathogens in immunocompromised patients. These species form pink-pigmented colonies on agar plates and have been frequently isolated from tap water in hospitals. Herein, we describe a case of vascular access-related bloodstream infection caused by Methylobacterium radiotolerans in an 82-year-old man who was undergoing hemodialysis and had an implanted permanent pacemaker. Gram-negative rods cultured from his peripheral blood after incubation for 7 days were identified as M. radiotolerans by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing. The patient was treated with meropenem and daptomycin for 8 days, and levofloxacin was subsequently given orally for 6 days. However, eleven days after completion of the treatment, the patient developed another febrile episode, and the vascular access line blood and his peripheral blood also grew M. radiotolerans. Meropenem and rifampicin were administered and the vascular access line was removed and replaced. Subsequently, oral levofloxacin and rifampicin treatment was maintained for 8 weeks and the patient recovered without removal of the permanent pacemaker. M. radiotolerans grew slowly in blood culture, and the isolate showed optimal growth on Reasoner's 2 Agar (R2A). To our knowledge, this is the first report of a hemodialysis vascular access-related bloodstream infection caused by M. radiotolerans in Japan. Our experience suggests that clinicians should be aware of the possibility of vascular access infection caused by M. radiotolerans.

Accuracy analysis of intrahepatic fat density measurements using dual-energy computed tomography: Validation using a test phantom.

BACKGROUND: Currently, no standardized method for measuring intrahepatic fat density via conventional computed tomography (CT) exists. OBJECTIVE: We aim to quantify intrahepatic fat density via material decomposition analysis using rapid kilovolt peak-switching dual-energy (RSDE) CT. METHODS: Homogenized porcine liver and fat (lard) were mixed in various ratios to produce phantoms for fat density verification. The actual fat density was measured on the basis of the phantom volume and weight, and these measurements were used as reference densities. The fat and liver mass attenuation coefficients, which were used as the material basis pairs, were employed in the material decomposition analysis. Then, the measured fat density of each phantom was compared with the reference densities. RESULTS: For fat content differences exceeding 2%, the measured fat density for the phantoms became statistically significant (p < 0.01). The correlation between the reference densities and RSDE-measured fat densities was reasonably high (R > 0.9997); this indicates the validity of this analysis method. CONCLUSIONS: Intrahepatic fat density can be measured using the mass attenuation coefficients of fat and liver in a material decomposition analysis. Given the knowledge of the accuracy and the limitations found in this study, our method can quantitatively evaluate fat density.

Visceral Abdominal Obesity Measured by Computed Tomography is Associated With Increased Risk of Colonic Diverticulosis.

GOALS: To investigate whether visceral obesity measured by computed tomography (CT) is a risk factor for colonic diverticulosis. BACKGROUND: The association between colonoscopy-proven diverticulosis and visceral obesity has not been studied. STUDY: A cohort of 1445 participants (1117 nondiverticulosis and 328 diverticulosis) undergoing colonoscopy and CT was prospectively analyzed. Diverticulosis was diagnosed by high-resolution colonoscopy. The associations between body mass index (BMI), visceral adipose tissue (VAT) area, subcutaneous adipose tissue (SAT) area, and diverticulosis were estimated using odds ratios (ORs) adjusted for age, sex, alcohol, smoking, medications, and comorbidities. RESULTS: In multivariate analysis, diverticulosis was significantly associated with VAT area and SAT area for both categorical data and trend (P for trend <0.001), but not BMI.Diverticulosis had a positive association with VAT area and SAT area for both categorical data and trend (P for trend <0.001) in men, but none of these associations were noted in women. In the subanalysis of normal-weight patients (BMI<25), diverticulosis was independently associated with VAT area and SAT area (P for trend <0.001). The adjusted ORs for VAT area ≥100 cm² was significantly increased in right-sided (OR, 1.8), left-sided (OR, 2.3), and bilateral (OR, 3.0) diverticula (P for trend <0.001). CONCLUSIONS: Abdominal obesity measured by CT, not BMI, is associated with colonic diverticulosis, even when body weight was normal. These findings suggest an important role for visceral fat accumulation in diverticulosis development. A high visceral fat was positively associated with the distribution of diverticula.

Visceral fat accumulation affects risk of colonic diverticular hemorrhage.

PURPOSES: Factors other than antithrombotic drugs associated with diverticular bleeding remain unknown. Visceral adiposity contributes to atherosclerosis and may affect arteriolar change at the diverticulum. We investigated whether visceral adipose tissue (VAT) measured by computed tomography (CT) is a risk factor for diverticular bleeding. METHODS: A cohort of 283 patients (184 with asymptomatic diverticulosis and 99 with diverticular bleeding) undergoing colonoscopy and CT was analyzed. Associations between body mass index (BMI), VAT, subcutaneous adipose tissue (SAT), and diverticular bleeding were assessed by logistic regression models adjusted for age, gender, alcohol, smoking, diabetes mellitus, hypertension, dyslipidemia, chronic kidney disease, and antithrombotic drugs (nonsteroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin, and other antiplatelet drugs). RESULTS: In univariate analysis, hypertension, dyslipidemia, chronic kidney disease, and NSAIDs use, low-dose aspirin, non-aspirin antiplatelets, increasing BMI, and increasing VAT area were associated with diverticular bleeding. In multivariate analysis adjusted for confounding factors, VAT area (p = 0.021), but not BMI (p = 0.551) or SAT area (p = 0.635), was positively associated with diverticular bleeding. When BMI was considered simultaneously, VAT area remained positively associated with diverticular bleeding (p = 0.018). However, none of obesity indices including VAT area were associated with recurrence of diverticular bleeding or prolonged hospitalization. CONCLUSIONS: This study presents new information on risk factors for diverticular bleeding. A large volume of visceral adipose tissue, but not BMI or SAT, appears to entail a risk for diverticular bleeding, after age, gender, metabolic factors, and antithrombotic drugs use adjustments.

Abdominal visceral fat accumulation measured by computed tomography associated with an increased risk of gallstone disease.

BACKGROUND AND AIM: Visceral adiposity is a strong determinant of insulin resistance, which decreases cholecystokinin response sensitivity, and increases cholesterol saturation in the gallbladder bile; thus, it potentially relates to gallstone disease development. We aimed to investigate whether visceral fat measured by computed tomography (CT) is a risk factor for gallstone disease. METHODS: A cohort of 717 participants undergoing CT and ultrasonography was analyzed. The associations between body mass index (BMI), visceral adipose tissue (VAT) area, subcutaneous adipose tissue (SAT) area, and gallstone disease were analyzed adjusted for age, sex, hypertension, diabetes, and dyslipidemia. RESULTS: In multivariate analysis, gallstone disease was significantly associated with VAT and SAT areas for both categorical data and trend (P for trend < 0.001, 0.009), but not body mass index (BMI). Among patients with BMI < 25, gallstone disease remained significantly associated with VAT area (P for trend 0.021) and SAT area (P for trend 0.005). Interactions between the obesity indices and being elderly on the risk of gallstone disease were found; specifically BMI (P = 0.005), SAT (P < 0.001), and VAT (P = 0.154). A significant association between all obesity indices and gallstone disease was seen in patients aged < 65 but not among those aged ≥ 65. However, no significant association was noted between the obesity indices and sex. CONCLUSIONS: CT-measured adipose tissue, rather than BMI, was a better predictor for risk of gallstone disease. This finding applies to younger people or even those with normal body weight, suggesting the importance of abdominal visceral fat accumulation in the development of gallstone disease.

Abdominal Fat Accumulation, as Measured by Computed Tomography, Increases the Risk of Ischemic Colitis: A Retrospective Case-Control Study.

BACKGROUND AND AIM: Visceral fat contributes to insulin resistance and atherosclerosis. We retrospectively investigated whether abdominal fat accumulation, as measured by computed tomography, is a risk of ischemic colitis and related clinical outcomes. MATERIALS AND METHODS: Outpatient-onset ischemic colitis patients (n = 58) and age- and sex-matched controls (n = 58) underwent colonoscopy and computed tomography. Associations between body mass index, visceral adipose tissue area, subcutaneous adipose tissue area, and ischemic colitis were estimated using odds ratios adjusted for hypertension, diabetes mellitus, and dyslipidemia. RESULTS: In multivariate analysis, ischemic colitis was significantly associated with subcutaneous adipose tissue area (P for trend 0.030) and marginally associated with visceral adipose tissue area (P for trend 0.094), but was not associated with body mass index (P for trend 0.460). The adjusted odds ratios for the highest quartile of subcutaneous and visceral adipose tissue in ischemic colitis were 3.48 (1.06-11.4) and 2.43 (0.74-8.00), respectively, compared with the lowest quartile. When body mass index was considered simultaneously, ischemic colitis remained associated with subcutaneous adipose tissue (P for trend 0.016) and visceral adipose tissue (P for trend 0.077). No significant differences were noted between any of the obesity indices and the distribution type of colitis, blood transfusion requirement, or length of hospital stay. CONCLUSION: Abdominal fat accumulation measured by computed tomography, but not body mass index, was associated with outpatient-onset ischemic colitis. Ischemic colitis remained associated with abdominal fat, even when body mass index was simultaneously considered. However, clinical outcomes of ischemic colitis were not associated with abdominal fat accumulation.

Visceral abdominal fat measured by computed tomography is associated with an increased risk of colorectal adenoma.

We investigated whether visceral adipose tissue (VAT) measured by computed tomography (CT) is a risk factor for colorectal adenoma. For a total of 1,328 patients (857 without adenoma, 471 with colorectal adenoma) undergoing colonoscopy and CT, associations between colorectal adenoma and body mass index (BMI), VAT area and subcutaneous adipose tissue (SAT) were assessed using odds ratios (ORs) with 95% confidence intervals (CIs) adjusted for age, sex, family history, smoking, alcohol intake, diabetes mellitus, aspirin use and nonsteroidal anti-inflammatory drug use. Multivariate analysis showed that colorectal adenoma was marginally associated (p=0.06) with BMI, but not with SAT, while it was significantly associated with VAT and the VAT to SAT ratio (VAT/SAT) for both categorical data and trend (p<0.05). When the obesity indices were considered simultaneously, colorectal adenoma remained significantly associated with VAT and VAT/SAT (p<0.05), but not BMI and SAT. In patients with colorectal adenoma, the adjusted OR for the highest quartiles of VAT and VAT/SAT was 1.90 (95% CI 1.16-3.13) and 2.25 (95% CI 1.49-3.41), respectively, compared to the lowest quartiles. Only VAT area was significantly associated with colorectal adenoma in both men and women (p<0.05). Proximal, multiple and advanced adenomas had significantly higher VAT areas (p<0.05) than distal, solitary and nonadvanced adenomas. Our findings implicate abdominal VAT in the development and progression of colorectal adenoma, and it was better obesity index for colorectal adenoma than BMI in both sexes.

Predictors for cecal insertion time: the impact of abdominal visceral fat measured by computed tomography.

BACKGROUND: Several factors affect the risk for longer cecal insertion time. OBJECTIVE: The aim of this study was to identify the predictors of longer insertion time and to evaluate the effect of visceral fat measured by CT. DESIGN: This is a retrospective observational study. PATIENTS: Outpatients for colorectal cancer screening who underwent colonoscopies and CT were enrolled. Computed tomography was performed in individuals who requested cancer screening and in those with GI bleeding. MAIN OUTCOME MEASURES: Information on obesity indices (BMI, visceral adipose tissue, and subcutaneous adipose tissue area), constipation score, history of abdominal surgery, poor preparation, fellow involvement, diverticulosis, patient discomfort, and the amount of sedation used was collected. RESULTS: The cecal insertion rate was 95.2% (899/944), and 899 patients were analyzed. Multiple regression analysis showed that female sex, lower BMI, lower visceral adipose tissue area, lower subcutaneous adipose tissue area, higher constipation score, history of surgery, poor bowel preparation, and fellow involvement were independently associated with longer insertion time. When obesity indices were considered simultaneously, smaller subcutaneous adipose tissue area (p = 0.038), but not lower BMI (p = 0.802) or smaller visceral adipose tissue area (p = 0.856), was associated with longer insertion time; the other aforementioned factors remained associated with longer insertion time. In the subanalysis of normal-weight patients (BMI <25 kg/m), a smaller subcutaneous adipose tissue area (p = 0.002), but not a lower BMI (p = 0.782), was independently associated with a longer insertion time. Longer insertion time had a positive correlation with a higher patient discomfort score (ρ = 0.51, p < 0.001) and a greater amount of midazolam use (ρ = 0.32, p < 0.001). LIMITATIONS: This single-center retrospective study includes a potential selection bias. CONCLUSIONS: In addition to BMI and intra-abdominal fat, female sex, constipation, history of abdominal surgery, poor preparation, and fellow involvement were predictors of longer cecal insertion time. Among the obesity indices, high subcutaneous fat accumulation was the best predictive factor for easier passage of the colonoscope, even when body weight was normal.

Validation of a surgical training model containing indocyanine green for near-infrared fluorescence imaging.

Objective: To determine the efficacy of a surgical training model for fluorescence-guided cancer surgery and validate its utility to detect any residual tumors after tumor resection using electrocautery. Methods: We developed surgical training models containing indocyanine green (ICG) for near-infrared (NIR) fluorescence imaging using a root vegetable organic material (konjac). After the fluorescence assessment for the models, the surgical simulation for fluorescence-guided cancer surgery using electrocautery was performed. ICG-containing tumors were divided into two surgical groups: "Enucleation" (removal of the entire visible tumor) and "Complete resection" (removal of the tumor with an appropriate 5-mm surgical margin). Results: All 12 ICG-containing tumors were clearly visible from the normal view but not from the flipped view. The tumor resection time was significantly longer in the "Complete resection" group than in the "Enucleation" group (p < .001). The ICG-containing tumors showed a high tumor-to background ratio from the normal (average = 45.8) and flipped (average = 19.2) views, indicating that the models including ICG-containing tumors were useful for a surgical simulation in fluorescence-guided surgery. The average mean fluorescence intensity of the wound bed was significantly higher in the "Enucleation" group than in the "Complete resection" group (p < .01). No decrease in fluorescence signal was found in the wound bed even at 2 days postresection. Conclusion: Our surgical training model containing a fluorescent agent is safe, inexpensive, not harmful for humans, and easy to dispose after use. Our model would be beneficial for surgeons to learn NIR fluorescence imaging and to accelerate fluorescence-guided cancer surgery into clinical application.

Messages from a medical library in the earthquake-prone zone.

On March 11, 2011 at 14:46 (Friday), a massive magnitude-9.0 earthquake attacked large areas of northeastern Japan, including Sendai City. The huge earthquake generated catastrophic tsunamis, leading to unprecedented disasters in the seacoast areas of the Tohoku region (about 20,000 dead and missing persons). Upon this earthquake, in Tohoku University Medical Library, a 3-storey earthquake-resistant building, most of books fell down from bookshelves on the second and third floors, but the bookshelves remained steady because of the effective fixation. Many piles of fallen books blocked up the walkways and the narrow passages between the bookshelves; namely, books are easily transformed to dangerous weapons in a shaking building. Fortunately, all library staffs and users evacuated outside the building without even a scratch. Importantly, we were able to open the first floor of the Medical Library on March 14 (Monday), because the first floor has been used for the Learning Commons, with open space for group meetings. We thus provided students, medical staffs, and faculty members with the comfortable place during the early stage of the disasters. In fact, medical staffs and faculty members worked hard over weekend to deal with many patients and clear the post-quake confusions. Moreover, electricity, gas, or water supply was not yet restored in most areas of Sendai City. In the earthquake-prone zones, the Medical Library should function as a facility that not only enhances information gathering but also provides the place like an oasis of relaxation for students and medical staffs upon great earthquakes.

Case-specific three-dimensional hologram with a mixed reality technique for tumor resection in otolaryngology.

OBJECTIVE: We report our first experience of using a case-specific three-dimensional (3D) hologram for tumor resection in otolaryngology to show the proof of concept. In addition, a questionnaire was administered to assess the usefulness of the mixed reality technique in otolaryngology. METHODS: A case-specific 3D hologram was developed from enhanced images of dynamic computed tomography, with reference to contrast-enhanced magnetic resonance images, and used for preoperative planning and intraoperative image reference. To evaluate the usefulness of the 3D hologram with head mount displays (HMDs), 18 attendings and resident otolaryngologists completed a questionnaire with the Likert scale. RESULTS: The case-specific 3D hologram on HMDs was successfully used by means of easy gesture-handling without any monitors preoperatively and intraoperatively. The experience of picturing the tumor localization and evaluating the surgical approach was statistically better using the 3D hologram on HMDs than using the computer images (P < .01). Similarly, the holograms were observed to be better for intraoperative application and surgical education than computer images (P < .01). CONCLUSION: We demonstrated the use of a case-specific 3D hologram for tumor resection in otolaryngology. The technology may be useful for preoperative planning and intraoperative image reference, especially for challenging cases, and surgical education. LEVEL OF EVIDENCE: NA.

Enhancing the use of computed tomography and cardiac catheterization angiography in Zambia: A project report on a global extension of medical technology in Japan.

Cardiovascular disease (CVD) is one of the leading causes of death in adults in Zambia among the non-communicable diseases. The Government of the Republic of Zambia through the Ministry of Health procured Japanese radiological systems, computed tomography, and angiography for the University Teaching Hospitals (UTHs) - Adult in 2015. However, the operation of these diagnostic systems has not been optimal due to lack of a proper maintenance service plan, lack of competent health professionals, and erratic supply of medical consumables. In this study, we report our experiences of providing intensive training to multidisciplinary healthcare teams of the radiology department at UTHs - Adult from 2017 to 2019 to strengthen the quality management system of the radiological equipment so as to provide effective healthcare services. However, the COVID-19 pandemic has had enormous negative impact on essential healthcare. Long-term support through continuous hands-on training must be provided to establish sustainable healthcare services.

Effect of body mass index and intra-abdominal fat measured by computed tomography on the risk of bowel symptoms.

BACKGROUND: This study aims to investigate the association between body mass index (BMI) or intra-abdominal fat measured by computed tomography (CT) and bowel symptoms. METHOD: A cohort of 958 Japanese adults who underwent colonoscopy and CT and completed questionnaires after excluding colorectal diseases was analyzed. Six symptoms (constipation, diarrhea, loose stools, hard stools, fecal urgency, and incomplete evacuation) using a 7-point Likert scale were evaluated between baseline and second questionnaire for test-retest reliability. Associations between BMI, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and symptom score were analyzed by a rank-ordered logistic model, adjusting for age, sex, smoking, and alcohol consumption, hypertension, diabetes mellitus, and dyslipidemia. RESULTS: Some bowel symptom scores were significantly (p<0.05) different between the age groups, sexes, smoking, and alcohol consumption. In multivariate analysis, constipation was associated with low BMI (p<0.01), low VAT area (p = 0.01), and low SAT area (p<0.01). Moreover, hard stools was associated with low BMI (p<0.01) and low SAT area (p<0.01). The remaining symptoms were not significantly associated with BMI or intra-abdominal fat. Test-retest reliability of bowel symptom scores with a mean duration of 7.5 months was good (mean kappa, 0.672). CONCLUSIONS: Both low BMI and low abdominal fat accumulation appears to be useful indicators of increased risk for constipation and hard stools. The long-term test-retest reliability of symptom score suggests that bowel symptoms relevant to BMI or visceral fat remain consistent over several months.