A novel imaging biomarker for prediction of cerebrovascular ischemic events: Pericarotid fat density.

BACKGROUND: To investigate the relationship between pericarotid fat density measured in carotid CTA and vulnerable carotid plaque. METHODS: This retrospective study included 374 participants who underwent carotid CTA between June 1, 2021, and December 1, 2021 (234 males, median age 68 years [interquartile range: 61-75]). Two groups, symptomatic and asymptomatic, were defined based on either diffusion-weighted MRI or a clinical history of acute ischemia or TIA within 6 months before or after CTA. The relationship between pericarotid fat density and cerebrovascular ischemic events was assessed using receiver operating characteristic analysis and binary logistic regression analysis. RESULTS: In the symptomatic group (n = 135), mean pericarotid fat density (-63.3 ± 21.7 vs. -81.7 ± 16.9 HU, respectively; p < 0.001) and median maximum plaque thickness (4 [interquartile range: 3-6] vs. 3.7 [interquartile range: 2.6-4.7] mm, respectively; p = 0.002) were higher, while plaque density (42.1 ± 19.6 vs. 50.6 ± 20.4 HU, respectively; p = 0.001) was lower compared to the asymptomatic group. Pericarotid fat density (OR: 1.038, 95% CI: 1.023-1.053, p < 0.001) was identified as an independent predictor for symptomatic patients. The optimal cut-off value for pericarotid fat density predicting symptomatic patients was estimated as -74 HU (area under the curve: 0.753, 95% CI:0.699-0.808, p < 0.001). Inter-reader agreement for pericarotid fat density was found to be almost perfect (intraclass correlation coefficient: 0.818, 95% CI: 0.770-0.856, p < 0.001). CONCLUSION: Pericarotid fat density may serve as an imaging biomarker in predicting acute cerebrovascular ischemic events.

Tigecycline-Associated Hepatic Steatosis After Liver Transplant: A Case Report.

Tigecycline is a parenteral glycycline antibiotic that is used to treat severe infections caused by susceptible organisms, butitis also associated with hepatotoxicity. We present 2 similar patients with hepatic steatosis possibly associated with early tigecycline after transplant. In the first case, a 61-year-old woman underwent liver transplant for acute severe hepatitis; 6 days posttransplant, because of nonroutine resistant fever, the patient received tigecycline combined with daptomycin. Retransplant was applied to the patient on day 12 posttransplant because of acute liver failure secondary to hepatic vein thrombosis. After retransplant, biochemical levels gradually increased, exceeding the upper limit of normal. In liver biopsy, the patient had macrovesicular steatosis in 70% to 80% ofthe parenchyma. In the second case, a 53-yearold woman underwent liver transplant for liver cirrhosis. Tigecycline was added to the treatment because of recurrent fever on day 6 after transplant, with treatment also comprising piperacillin-tazobactam and meropenem. On day 15 of the patient's tigecycline treatment, her liver function tests were elevated. In liver biopsy, the patient had 30% to 40% macrovesicular steatosis and canalicular cholestasis in the parenchyma, especially in zone 3. Reports of hepatic steatosis associated with early tigecycline after transplant are quite new to the literature.

Effect of Pretransplant Sarcopenia on Mortality in Liver Transplant Recipients.

OBJECTIVES: Sarcopenia is an important metabolic disorder associated with end-stage liver disease and is an independent predictor of mortality in liver transplant candidates. We evaluated effects of pretransplant muscle mass, muscle quality, and visceral adipose tissue on mortality after liver transplant. MATERIALS AND METHODS: For 2015-2020, we included 65 liver transplant recipients whose records contained pretransplant liver computed tomography images. We calculated skeletal muscle mass index (muscle tissue area in centimeters squared divided by height in meters squared), visceral-to-subcutaneous fat ratio (visceral adiposity indicator), and intramuscular adipose tissue content ratio (muscle quality indicator). RESULTS: Median age was 55 years (IQR, 45-63 years), and 48 (73.8%) patients were men. During follow-up, 53 (81.5%) study group patients survived; mean survival time was 71.73 ± 3.81 months. The deceased patient group had a statistically higher pretransplant visceral-to-subcutaneous fat ratio than the survival group (P = .046). Survival was 100% for 1 positive indicator, 86.2% for 2 positive indicators, and 70.4% for 3 positive indicators (P = .096). Positive correlation was confirmed between pretransplant skeletal muscle mass index and age (P = .043) and pretransplant body mass index (weight in kilograms divided by height in meters squared) (P < .001). There was a moderate positive correlation between pretransplant intramuscular adipose tissue content ratio and age (R = 0.529, P ≤ .001) and a weak positive correlation with pretransplant body mass index (R = 0.361, P = .003). Furthermore, pretransplant visceral- tosubcutaneous fat ratio showed a weak positive correlation with age (R = 0.306, P = .013) and a weak negative correlation with the Model for End-Stage Liver Disease score (R = -0.301, P = .016). CONCLUSIONS: Pretransplant sarcopenia is an important indicator to predict mortality and morbidity in posttransplant follow-up. Visceral-to-subcutaneous fat ratio is an important parameter to evaluate sarcopenia in liver transplant patients.

Comparison of clinical characteristics of wild-type SARS-CoV-2 and Omicron.

OBJECTIVE: This study aimed to investigate the effect of mutations by comparing wild-type SARS-CoV-2 and Omicron regarding clinical features in patients with COVID-19. It also aimed to assess whether SARS-CoV-2 cycle threshold value could predict COVID-19 severity. METHODS: A total of 960 wild-type and 411 Omicron variant patients with positive results in SARS-CoV-2 real-time reverse transcriptase polymerase chain reaction test from oropharyngeal and/or nasopharyngeal samples during their hospital admissions were included in this retrospective study. The reference symptoms of the patients were obtained from the hospital database. The correlation between chest computed tomography findings and the "cycle threshold" of patients with wild-type SARS-CoV-2 was assessed. RESULTS: Cough, fever, shortness of breath, loss of taste and smell, and diarrhea were found to be statistically significantly higher (p=0.001; 0.001; 0.001; 0.001; and 0.006; respectively) in the wild-type cohort, while in the Omicron cohort, sore throat and headache were found to be statistically significantly higher (p=0.001 and 0.003, respectively). An inverse relationship was found between chest computed tomography findings and viral load. CONCLUSION: This study revealed that the Omicron variant tended to infect predominantly the upper respiratory tract and showed decreased lung infectivity, and the disease progressed with a milder clinical course. Therefore, the study showed that the tropism of the virus was changed and the viral phenotype was affected. It was also found that SARS-CoV-2 viral load did not predict COVID-19 severity in patients with wild-type SARS-CoV-2.

Pacemaker-associated superior vena cava syndrome: Role of contrast echocardiography.

Pacemaker-associated superior vena cava (SVC) syndrome is increasingly recognized as a nonmalignant type of SVC syndrome. Computed tomographic (CT) angiography is the first choice of imaging for diagnosis but in some cases there is discrepancy between the clinical findings and CT images. In this report we present the role of contrast study with transesophageal echocardiography in a patient with suspicion of SVC syndrome but inconclusive CT findings.

Severe main coronary artery disease in a young woman with ankylosing spondylitis.

Patients with ankylosing spondylitis (AS) have an approximately two-fold increased death rate compared to the general population, which is predominately caused by increased cardiovascular risk. The prevalence rate for myocardial infarction is approximately 2-3 fold increased as compared with the general population. The inflammatory process appears to have an important role in causing this excess cardiovascular risk. In this paper, we present a case of severe coronary artery disease which could be demonstrated clearly by computer tomography in a 27-year-old woman who is being followed with AS.

Gastric subepithelial masses: evaluation of multidetector CT (multiplanar reconstruction and virtual gastroscopy) versus endoscopic ultrasonography.

OBJECTIVES: To assess the role of multidetector computed tomography (MDCT) with multiplanar reconstruction (MPR) and virtual gastroscopy (VG) for detection and differentiation of gastric subepithelial masses (SEMs) by comparison with endoscopic ultrasonography (EUS). METHODS: Forty-one patients with a suspected SEM were evaluated using EUS and MDCT. MDCT findings were analyzed based on the consensus of two radiologists who were blinded to the EUS findings. The analysis of the CT features included the location, size, and contours of the tumor, the presence of central dimpling, as well as the growth pattern, enhancement pattern, and enhancement degree. The long diameter (LD) and the short diameter (SD) of each lesion were measured and the LD/SD ratios were calculated. EUS and MDCT results were compared with histopathology for the pathologically proven lesions. For the non-pathologically proven lesions, MDCT results were compared with EUS. RESULTS: Among the 41 patients, 34 SEMs were detected using EUS. For the detection of SEMs with MDCT, a sensitivity of 85.3%, a specificity of 85.7%, a positive predictive value of 96.7%, and a negative predictive value of 54.5% were calculated. The overall accuracy of MDCT for detecting and classifying the SEMs was 85.3 and 78.8%, respectively. CONCLUSIONS: MDCT with MPR and VG is a valuable method for the evaluation of SEMs. Specific MDCT criteria for various SEMs may be helpful in making an accurate diagnosis.

Percutaneous biliary intervention for primary sclerosing cholangitis in a patient with situs inversus totalis.

Situs inversus totalis is a rare condition that may not cause symptoms and often occurs concomitantly with other congenital anomalies. Special attention must be given to these patients when invasive interventions are required. There are only a few reports concerning percutaneous transhepatic biliary interventions in situs inversus totalis, but technical details were not fully explained. In this report, we attempt to explain the technical details of percutaneous transhepatic cholangiography, percutaneous biliary drainage and percutaneous biliary balloon dilatation in a patient with known primary sclerosing cholangitis and situs inversus totalis. While performing percutaneous biliary interventions in patients with situs inversus totalis, the key point is to use the mirror image of the traditional technique in an imaginary line dissecting the midline of the abdomen.