Accuracy of pilot balloon palpation for cuff pressure assessment in small versus large sized tubes: a prospective non-randomized observational study.

Pilot balloon palpation is still a commonly used method to evaluate cuff pressure of the endotracheal tube after intubation. This study determined whether the size of the tracheal tube influenced the accuracy of pilot balloon palpation. A prospective observational analysis of 208 patients intubated with an endotracheal tube of internal diameter (ID) 6.0 or 8.0 was conducted. An anesthesiologist judged the cuff pressure by manual pilot balloon palpation, and then measured the cuff pressure with a pressure gauge. Cuff pressure exceeding 20-30 cmH2O was defined as false recognition. The intracuff pressure was significantly higher in ID 6.0 tube than in the ID 8.0 tube (41.9 ± 18.8 cmH2O vs. 30.3 ± 11.9 cmH2O, p < 0.001). The number of patients that were mistakenly perceived to have appropriate cuff pressure by pilot balloon palpation was significantly higher in the ID 6.0 group compared to the ID 8.0 group (85 (81.7%) vs. 64 (61.5%), p = 0.001). Therefore, a smaller tube size may further increase risk of inaccurate measurement by pilot balloon palpation and although pressure gauge is recommended for all sizes to maximize accuracy, groups with increased risk factors should be targeted for standardized use of the pressure gauge.

Safety Assessment of Starch Nanoparticles as an Emulsifier in Human Skin Cells, 3D Cultured Artificial Skin, and Human Skin.

Emulsion systems are widely used in various industries, including the cosmetic, pharmaceutical, and food industries, because they require emulsifiers to stabilize the inherently unstable contact between oil and water. Although emulsifiers are included in many products, excessive use of emulsifiers destroys skin barriers and causes contact dermatitis. Accordingly, the consumer demand for cosmetic products made from natural ingredients with biocompatibility and biodegradability has increased. Starch in the form of solid nanosized particles is considered an attractive emulsifier that forms and stabilizes Pickering emulsion. Chemical modification of nanosized starch via acid hydrolysis can effectively provide higher emulsion stability. However, typical acid hydrolysis limits the industrial application of starch due to its high time consumption and low recovery. In previous studies, the effects of starch nanoparticles (SNPs) prepared by treatment with acidic dry heat, which overcomes these limitations, on the formation and stability of Pickering emulsions were reported. In this study, we evaluated the safety of SNPs in skin cell lines, 3D cultured skin, and human skin. We found that the cytotoxicity of SNPs in both HaCaT cells and HDF cells could be controlled by neutralization. We also observed that SNPs did not induce structural abnormalities on 3D cultured skin and did not permeate across micropig skin tissue or human skin membranes. Furthermore, patches loaded with SNPs were found to belong in the "No irritation" category because they did not cause any irritation when placed on human skin. Overall, the study results suggest that SNPs can be used as a safe emulsifier in various industries, including in cosmetics.

Controlled attenuation parameter measured using transient elastography for the noninvasive assessment of macrovesicular steatosis in potential living liver donors.

PURPOSE: This study aimed to determine the diagnostic performance of the controlled attenuation parameter (CAP) measured using transient elastography (TE) for assessing macrovesicular steatosis (MaS) in potential living liver donors using same-day biopsy as a reference standard. METHODS: This retrospective study included 204 living liver donor candidates who underwent TE and liver biopsy on the same day between July 2013 and June 2014. The histologic degree of MaS was determined. The area under the receiver operating characteristic curve (AUROC) was used to evaluate the performance of CAP for diagnosing MaS of >10%, and the optimal cutoff value was identified using the maximal Youden index. RESULTS: Based on liver biopsy, 185 subjects had MaS of ≤10% and 19 had MaS of >10%. The CAP value was significantly correlated with the percentage of MaS on liver biopsy (r=0.635, P<0.001), and the median CAP value was significantly higher in subjects with MaS of >10% than in those with MaS of ≤10% (300 dB/m vs. 209 dB/m, P<0.001). The AUROC for diagnosing MaS of >10% by CAP was 0.938 (95% confidence interval, 0.896 to 0.967), and a CAP of >259 dB/m yielded a sensitivity of 84.2% and a specificity of 92.4%. CONCLUSION: The CAP measured using TE was significantly correlated with MaS and accurately detected substantial MaS in potential living liver donors. The CAP is a promising tool for the noninvasive diagnosis of MaS and may be used to screen unsuitable living liver donor candidates.

Absence of attack-independent neuroaxonal injury in MOG antibody-associated disease: Longitudinal assessment of serum neurofilament light chain.

To evaluate the occurrence of attack-independent neuroaxonal and astrocytic damage in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) levels were longitudinally measured in 102 sera using a single-molecule array assay. Sera from 15 adults with relapsing MOGAD with available longitudinal samples for the median 24-month follow-up and 26 age-/sex-matched healthy controls were analyzed. sNfL levels were significantly elevated in all clinical attacks, where the levels decreased below or close to cut-off value within 6 months after attacks. sNfL levels were consistently low during inter-attack periods. In contrast, sGFAP levels did not increase in most clinical attacks and remained low during follow-up. Significant neuroaxonal damage was observed at clinical attacks, while attack-independent neuroaxonal and astrocytic injury was absent in MOGAD.

Quantitative ultrasound radiofrequency data analysis for the assessment of hepatic steatosis using the controlled attenuation parameter as a reference standard.

PURPOSE: This study was aimed to investigate the value of quantitative ultrasound (US) parameters from radiofrequency (RF) data analysis for assessing hepatic steatosis, using controlled attenuation parameter (CAP)-based steatosis grades as the reference standard. METHODS: We analyzed 243 participants with both B-mode liver US with RF data acquisition and CAP measurements. On B-mode US images, hepatic steatosis was visually scored (0/1/2/3, none/mild/moderate/severe), and the hepatorenal index (HRI) was calculated. From the RF data analysis, the tissue scatter-distribution imaging parameter (TSI-p) and tissue attenuation imaging parameter (TAI-p) of the liver parenchyma were measured. US parameters were correlated with CAP-based steatosis grades (S0/1/2/3, none/mild/moderate/severe) and their diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis. Multivariate linear regression analysis was performed to identify determinants of TSI-p and TAI-p. RESULTS: Participants were classified as having S0 (n=152), S1 (n=54), S2 (n=14), and S3 (n=23) on CAP measurements. TSI-p and TAI-p were significantly correlated with steatosis grades (ρ =0.593 and ρ=-0.617, P<0.001 for both). For predicting ≥S1, ≥S2, and S3, the areas under the ROC curves (AUCs) of TSI-p were 0.827/0.914/0.917; TAI-p, 0.844/0.914/0.909; visual scores, 0.659/0.778/0.794; and HRI, 0.629/0.751/0.759, respectively. TSI-p and TAI-p had significantly higher AUCs than did visual scores or HRI for ≥S1 or ≥S2 (P≤0.003). In the multivariate analysis, the transient elastography-based fibrosis grade (P=0.034) and steatosis grade (P<0.001) were independent determinants of TSI-p, while steatosis grade (P<0.001) was an independent determinant of TAI-p. CONCLUSION: TSI-p and TAI-p derived from US RF data may be useful for detecting hepatic steatosis and assessing its severity.

Post-operative assessment in patients after liver transplantation: imaging parameters associated with 1-year graft failure.

PURPOSE: To identify post-liver transplant CT findings which predict graft failure within 1 year. MATERIALS AND METHODS: We evaluated the CT scans of 202 adult liver transplants performed in our institution who underwent CT within 3 months after transplantation. We recorded CT findings of liver perfusion defect (LPD), parenchymal homogeneity, and the diameters and attenuations of the hepatic vessels. Findings were correlated to 1-year graft failure, and interobserver variability was assessed. RESULTS: Forty-one (20.3%) of the 202 liver grafts failed within 1 year. Graft failure was highly associated with LPD (n = 18/25, or 67%, versus 15/98, or 15%, p < 0.001), parenchymal hypoattenuation (n = 20/41, or 48.8% versus 17/161, or 10.6%, p < 0.001), and smaller diameter of portal veins (right portal vein [RPV], 10.7 ± 2.7 mm versus 14.7 ± 2.2 mm, and left portal vein [LPV], 9.8 ± 3.0 mm versus 12.4 ± 2.2 mm, p < 0.001, respectively). Of these findings, LPD (hazard ratio [HR], 5.43, p < 0.001) and small portal vein diameters (HR, RPV, 3.33, p < 0.001, and LPV, 3.13, p < 0.05) independently predicted graft failure. All the measurements showed fair to moderate interobserver agreement (0.233~0.597). CONCLUSION: For patients who have CT scan within the first 3 months of liver transplantation, findings of LPD and small portal vein diameters predict 1-year graft failure. KEY POINTS: •Failed grafts are highly associated with liver perfusion defect, hypoattenuation, and small portal vein. •Right portal vein < 11.5 mm and left portal vein < 10.0 mm were associated with poor graft outcome. •Liver perfusion defect and small portal vein diameter independently predicted graft failure.

Hepatocyte-Specific Magnetic Resonance Imaging-Based Assessment of Indeterminate Hepatic Nodules in the Liver Transplant Evaluation of Patients With Cirrhosis.

We aimed to determine the identities in explants of indeterminate hepatic nodules (IDNs) that had been scanned by dynamic magnetic resonance imaging (MRI) to establish clinicoradiological parameters predicting which IDNs were hepatocellular carcinomas (HCCs). This study included 88 patients with cirrhosis who underwent gadoxetic acid-enhanced MRI in pre-liver transplantation (LT) workup followed within 90 days by primary LT. The MRI detected 168 hepatic nodules that were classified into 6 benign tumors, 49 HCCs, and 113 IDNs, in 5, 34, and 72 patients, respectively. We compared these pre-LT radiologic diagnoses and stagings with explant pathology on a per-lesion basis to enable us to identify features of IDNs related to malignancy. Of the 168 nodules seen on MRI, 119 that were classified radiologically as consisting of 1 benign nodule (33.3%), 46 HCCs (93.9%), and 72 IDNs (63.7%) all turned out to be pathological HCCs. Of 32 patients inside Milan and 54 without HCC staged by MRI, 11 progressed beyond the criteria after LT. High serum alpha-fetoprotein level (≥20 ng/mL) was the only per-patient factor significantly associated with malignant IDNs. Per-tumor analysis of the MRI signals revealed that arterial hyperintensity, hepatobiliary hypointensity, T2 -weighted mild-to-moderate intensity, and restricted diffusion-weighted images were significantly correlated with malignant IDN. A model combining these 4 MRI factors with alpha-fetoprotein level had the best performance in predicting the identification of IDNs as HCCs in explanted livers. Over 60% of the IDNs seen on dynamic images of cirrhotic livers proved to be HCCs when explanted livers were examined. It may therefore be possible to identify HCCs with reasonable accuracy by means of their hepatocyte-specific MRI features when patients are being assessed for LT.

Validation of a New Point Shear-Wave Elastography Method for Noninvasive Assessment of Liver Fibrosis: A Prospective Multicenter Study.

OBJECTIVE: To validate the diagnostic value of a new point shear-wave elastography method, S-shearwave elastography (S-SWE; Samsung Medison Co., Ltd.), in noninvasive assessment of liver fibrosis. MATERIALS AND METHODS: In this prospective multicenter study, liver stiffness (LS) measurements for 600 participants were obtained with both S-SWE and transient elastography (TE). The rates of unsuccessful LS measurements in S-SWE and TE were compared, and correlations between S-SWE and TE measurements were assessed. In 107 patients with histologic reference data, the optimal LS cut-off values for predicting severe fibrosis and cirrhosis on S-SWE were determined using receiver operating characteristic (ROC) curve analysis. The LS cut-off values in S-SWE were then validated in 463 patients without histologic reference data by using TE values as the reference standard, and the sensitivity and specificity of the cut-off values for predicting severe fibrosis and cirrhosis were calculated. RESULTS: The frequency of unsuccessful LS measurements on TE (4.5%, 27/600) was significantly higher than that (0.7%, 4/600) on S-SWE (p < 0.001). LS measurements on S-SWE showed a significant correlation with TE values (r = 0.880, p < 0.001). In 107 patients with histological reference data, the areas under the ROC curves on S-SWE were 0.845 and 0.850, with optimal cut-offs of 7.0 kilopascals (kPa) and 9.7 kPa, for the diagnosis of severe fibrosis and cirrhosis, respectively. Using these cut-off values, S-SWE showed sensitivities of 92.9% and 97.4% and specificities of 89.5% and 83.1% in TE-based evaluations of severe fibrosis and cirrhosis, respectively. CONCLUSION: LS measurements on S-SWE were well correlated with those on TE. In addition, S-SWE provided good diagnostic performance for staging of hepatic fibrosis, with a lower rate of unsuccessful LS measurements compared with TE.

Prospective observations study protocol to investigate cost-effectiveness of various prenatal test strategies after the introduction of noninvasive prenatal testing.

BACKGROUND: Among the non-invasive screening methods for the identification of fetal aneuploidy, NIPT (non-invasive prenatal testing) shows the highest sensitivity and specificity in high-risk pregnancies. Due to the low false positive rate of NIPT, it is assumed that the implementation of NIPT as a primary screening method may reduce the number of invasive fetal tests and result in a similar or lowered cost in the overall detection of Down syndrome. However, most previous studies are based on theoretical economic analysis. This study aims to determine the cost effectiveness of various prenatal test strategies, including NIPT, in real clinical settings in both low risk and high risk pregnancies. METHODS/DESIGN: In this prospective observational study, women (< 24 weeks) with singleton or twin pregnancies will be enrolled in 12 different healthcare institutions. The participants will be grouped based on the risks of fetal chromosomal abnormalities and will be counseled on the various screening or diagnostic methods, including NIPT, according to the aneuploidy risk. The final decision on screening or diagnostic methods will be made by patients after counseling. Questionnaires regarding factors affecting the decision on prenatal test will be answered by the participants and physicians. The economic analysis on final total costs will be compared according to the various prenatal test strategies. DISCUSSION: The results of present study are expected to have a significant impact on national policies in determining Korean prenatal screening test strategies and to help in developing novel and effective prenatal screening tests in the future.

Assessment of Liver Function Using Pharmacokinetic Parameters of Gd-EOB-DTPA: Experimental Study in Rat Hepatectomy Model.

Objectives: To determine whether the pharmacokinetic parameters of Gd-EOB-DTPA can identify the difference in liver function in a rat hepatectomy model. Methods: A total of 56 eight-week-old male Sprague-Dawley rats were divided into the following groups: control group without hepatectomy (n = 16), 70% hepatectomy group (n = 14), and 90% hepatectomy group (n = 26). On postoperative day 2, Gd-EOB-DTPA (0.1 mmol/kg) was injected intravenously and serial blood samples were obtained. Pharmacokinetic analysis was performed using a noncompartmental method. Statistical analysis was performed using one-way analysis of variance and post hoc pairwise group comparisons. Results: After excluding 6 rats that died unexpectedly, blood samples were obtained from 16, 14, and 20 rats in the control group, 70% hepatectomy group, and 90% hepatectomy group. There was a significant increase in area under the concentration-time curve from time zero to the time of the last measurable concentration between the 70% and 90% hepatectomy group (P < 0.001). The volume of distribution at steady state was significantly decreased between the control and 70% hepatectomy group (P < 0.001). The clearance was significantly different in all pairwise group comparisons (P < 0.001). Conclusions: The vascular clearance of Gd-EOB-DTPA can identify the difference in liver function in a rat hepatectomy model.

Noninvasive assessment of hepatic sinusoidal obstructive syndrome using acoustic radiation force impulse elastography imaging: A proof-of-concept study in rat models.

OBJECTIVES: To determine the feasibility of acoustic radiation force impulse (ARFI) elastography in the evaluation of hepatic sinusoidal obstruction syndrome (SOS) in rat models. METHODS: Rat SOS models of various severities were created by monocrotaline gavage (n = 40) or by intraperitoneal injection of 5-fluorouracil, leucovorin and oxaliplatin (FOLFOX) (n = 16). Liver shear-wave velocity (SWV) was measured using ARFI elastography. Liver samples were analysed for the SOS score, steatosis, lobular inflammation and fibrosis. RESULTS: The liver SWV was significantly elevated in the SOS models (1.29-2.24 m/s) compared with that of the matched control rats (1.01-1.09; p≤.09; veFor seven FOLFOX-treated rats which were longitudinally followed-up, the liver SWV significantly increased at 7 weeks (1.32±0.13 m/s) compared with the baseline (1.08±0.1 m/s, p=.015) and then significantly declined after a 2-week, treatment-free period (1.15±0.13 m/s; p=.048). Multivariate analysis revealed that the SOS score (p<.001) and lobular inflammation (p=.044) were independently correlated with the liver SWV. CONCLUSION: Liver SWV is elevated in SOS in proportion to the degree of sinusoidal injury and lobular inflammation in rat SOS models. ARFI elastography has potential as an examination for diagnosis, severity assessment and follow-up of SOS. KEY POINTS: • Liver SWV using ARFI elastography was significantly elevated in SOS rat. • Sinusoidal injury and lobular inflammation grades had correlation with liver SWV. • ARFI elastography has potential for diagnosis, severity assessment, and follow-up of SOS.

Performing Gadoxetic Acid-Enhanced MRI After CT for Guiding Curative Treatment of Early-Stage Hepatocellular Carcinoma: A Cost-Effectiveness Analysis.

OBJECTIVE: We determined the cost-effectiveness of two different diagnostic imaging strategies in guiding curative treatment of early-stage hepatocellular carcinoma (HCC). MATERIALS AND METHODS: We developed a decision analytic model using as its starting point a cohort of patients aged 55 years with early-stage HCC detected at dynamic multiphasic CT and with Child-Pugh class A cirrhosis. The model compared two strategies on the initial workup: conventional CT strategy using dynamic multiphasic CT only and gadoxetic acid-enhanced MRI strategy using additional gadoxetic acid-enhanced MRI after initial CT. A Markov cohort model simulated a cohort of patients after curative or adjuvant treatment, with follow-up over the remaining life expectancy. We analyzed mean life-years gain, quality-adjusted life-years (QALYs), costs per person, and incremental cost-effectiveness ratio (ICER). To evaluate results, we performed one-way, two-way, and probabilistic sensitivity analyses. RESULTS: The life expectancies and QALY were 7.22 years and 5.08 for the conventional CT strategy and 7.79 years and 5.52 for the gadoxetic acid-enhanced MRI strategy, respectively. The expected costs were $99,770 for conventional CT and $105,025 for gadoxetic acid-enhanced MRI in the United States. The ICER with gadoxetic acid-enhanced MRI was $11,957, as opposed to that with conventional CT, which was lower than the cost-effectiveness threshold of $50,000/QALY. One-way, two-way, and probabilistic sensitivity analyses showed unchanged results over an acceptable range. CONCLUSION: Gadoxetic acid-enhanced MRI after CT is cost-effective for detecting additional HCC in patients with early-stage HCC who can undergo curative treatment (besides liver transplantation). The cost-effectiveness of gadoxetic acid-enhanced MRI may be considered in the management of patients with early-stage HCC during staging.

Overview of the development of the Korean exposure factors handbook.

A set of exposure factors that reflects the characteristics of individual behavior capable of influencing exposure is essential for risk and exposure assessment. In 2007, the Korean Exposure Factors Handbook was, therefore, issued, driven by the need to develop reliable exposure factors representing the Korean population. The purpose of this study was to overview the development process of the Korean Exposure Factors Handbook and major recommended exposure values for the Korean population to allow information exchanges and comparison of recommended values among nations. The researchers reviewed the domestic data that could be used in the development of exposure factors, confirmed a knowledge gap, and set a priority of development by phases. A methodology to measure exposure factors was established to develop measuring techniques and test their validity. Data were processed or a survey was conducted according to the availability of data. The study thus produced recommended values for 24 exposure factors grouped by general exposure factors, food ingestion factors, and activity factors by setting up a database of exposure factors and carrying out statistical analysis. The study has significantly contributed to reducing the potential uncertainty of the risk and exposure assessment derived by the application of foreign data or research findings lacking representativeness or grounds by developing a set of exposure factors reflecting the characteristics of the Korean people. It will be necessary to conduct revisions in light of the changing statistical values of national data and the exposure factors based on Korean characteristics.

General factors of the Korean exposure factors handbook.

Risk assessment considers the situations and characteristics of the exposure environment and host. Various physiological variables of the human body reflects the characteristics of the population that can directly influence risk exposure. Therefore, identification of exposure factors based on the Korean population is required for appropriate risk assessment. It is expected that a handbook about general exposure factors will be used by professionals in many fields as well as the risk assessors of the health department. The process of developing the exposure factors handbook for the Korean population will be introduced in this article, with a specific focus on the general exposure factors including life expectancy, body weight, surface area, inhalation rates, amount of water intake, and soil ingestion targeting the Korean population. The researchers used national databases including the Life Table and the 2005 Time Use Survey from the National Statistical Office. The anthropometric study of size in Korea used the resources provided by the Korean Agency for Technology and Standards. In addition, direct measurement and questionnaire surveys of representative samples were performed to calculate the inhalation rate, drinking water intake, and soil ingestion.

Activity factors of the Korean exposure factors handbook.

Exposure factors based on the Korean population are required for making appropriate risk assessment. It is expected that handbooks for exposure factors will be applied in many fields, as well as by health department risk assessors. The present article describes the development of an exposure factors handbook that specifically focuses on human activities in situations involving the possible risk of exposure to environmental contaminants. We define majour exposure factors that represent behavioral patterns for risk assessment, including time spent on routine activities, in different places, on using transportation, and engaged in activities related to water contact including swimming, bathing and washing. Duration of residence and employment are also defined. National survey data were used to identify recommended levels of exposure factors in terms of time spent on routine activities and period of residence and employment. An online survey was conducted with 2073 subjects who were selected using a stratified random sampling method in order to develop a list of exposure factors for the time spent in different places and in performing water-related activities. We provide the statistical distribution of the variables, and report reference levels of average exposure based on the reliable data in our exposure factors handbook.

Quantitative assessment of pancreatic fat by using unenhanced CT: pathologic correlation and clinical implications.

PURPOSE: To assess the relationship between computed tomographic (CT) indexes and histologically measured pancreatic fat in surgical specimens and to evaluate patients with impaired glucose metabolism in a clinical setting. MATERIALS AND METHODS: This retrospective study was institutional review board approved and informed consent was waived. The hospital database was searched for records from November 2008 to April 2009, and 62 patients (42 men and 20 women; mean age, 61.4 years; age range, 21-81 years) who underwent CT within 1 month before pancreatectomy were identified. The histologic pancreatic fat fraction (area ratio of fat to total tissue times 100%) was measured in nontumorous pancreatic tissue. Attenuation was measured in three regions of interest in the pancreas and the spleen on nonenhanced CT images. The difference between pancreatic and splenic attenuation and the pancreas-to-spleen attenuation ratio were calculated. Visceral fat area at the level of the umbilicus was measured on the CT images. Spearman correlation coefficients (ρ) were calculated to examine the correlation between the CT indexes or visceral fat area and the histologic pancreatic fat fraction. A multivariate logistic regression model was used to determine whether CT attenuation indexes and patient age, sex, and visceral fat correlated with impaired glucose metabolism (ie, impaired glucose tolerance, impaired fasting glucose, or presence of diabetes). RESULTS: The histologic pancreatic fat fraction ranged from 0% to 65.3% and was significantly correlated with the difference between pancreatic and splenic attenuation (ρ = -0.622, P < .01) and the pancreas-to-spleen attenuation ratio (ρ = -0.616, P < .01). The visceral fat area was not correlated with the histologic pancreatic fat fraction (ρ = 0.09, P = .50). The CT attenuation indexes were significant and independent variables predictive of impaired glucose metabolism after adjusting for age, sex, and visceral fat. CONCLUSION: Pancreatic fat can be quantified by using CT, and CT attenuation indexes that are applied to the quantification of pancreatic fat are significantly associated with clinical assessment of impaired glucose metabolism.

Assessment of hepatic function with Gd-EOB-DTPA-enhanced hepatic MRI.

Assessment of hepatic function is essential in determining the prognosis and clinical management of a patient who has chronic liver disease or undergoes liver surgery. For a patient with locally varying hepatic parenchymal abnormalities, a regional assessment of hepatic function mapped onto hepatic anatomy is clinically more meaningful than conventional global metrics of hepatic function. Of late, hepatic magnetic resonance imaging has been increasingly used because of its superb tissue contrast and delineation of hepatic morphology and underlying abnormalities. The introduction of hepatocyte-specific contrast agents such as Gd-EOB-DTPA allows us to view not only the hepatic anatomy but also assess regional hepatic function. In this article, we review and discuss recently published studies that used Gd-EOB-DTPA-enhanced magnetic resonance imaging to evaluate hepatic function.

Assessment of three dimensional quantitative coronary analysis by using rotational angiography for measurement of vessel length and diameter.

The aim of the study was to assess the accuracy of the three-dimensional (3D) quantitative coronary analysis (QCA) system by comparing with that of intravascular ultrasound (IVUS) QCA and two-dimensional (2D) QCA. 3D QCA, 2D QCA and IVUS QCA were performed in 45 vessel segments. The obtained values for the branch to branch segment vessel length and the proximal part of the segment vessel's lumen diameter were measured. Inter-technique agreement was analyzed using paired sample t-test and Bland-Altman analysis. No differences were found in vessel lengths taken by 3D QCA and IVUS QCA (mean difference: 0.29 ± 1.06 mm, P = 0.07). When compared with IVUS QCA, 2D QCA underestimated vessel length (mean difference: -1.78 ± 2.55, P < 0.001). Bland-Altman analysis showed close agreement and a small bias between 3D QCA and IVUS QCA in the measurement of vessel length. The vessel lumen diameter measurements by 2D QCA and 3D QCA were significantly lower than that by IVUS QCA (mean difference: -0.64 ± 0.69, P < 0.001; -0.56 ± 0.52, P < 0.001 respectively). Rotational angiography with 3D reconstruction can provide a more accurate vessel length measurement, whereas 2D and 3D QCA underestimated the vessel lumen diameter compared with IVUS QCA.

Non-invasive assessment of hepatic steatosis: prospective comparison of the accuracy of imaging examinations.

BACKGROUND & AIMS: Despite increasing use of various imaging examinations for non-invasive assessment of hepatic steatosis (HS), their relative accuracy is unknown. The objective of this study is to prospectively compare the accuracy of computed tomography (CT), dual gradient echo magnetic resonance imaging (DGE-MRI), proton magnetic resonance spectroscopy ((1)H-MRS), and ultrasonography (US) for the diagnosis and quantitative estimation of HS. METHODS: A total of 161 consecutive potential living liver donors underwent US (performed by two independent radiologists, US1 and US2), CT, DGE-MRI, (1)H-MRS, and liver biopsy on the same day. Using the histologic degree of HS as the reference standard, we compared the diagnostic performance of US1, US2, CT, DGE-MRI, and (1)H-MRS for diagnosing HS >or= 5% and HS >or= 30% and compared the accuracy of CT, DGE-MRI, and (1)H-MRS in the quantitative estimation of HS. RESULTS: DGE-MRI and (1)H-MRS significantly outperformed CT and US for the diagnosis of HS5%. DGE-MRI showed a tendency of higher accuracy than the other examinations for diagnosing HS >or= 30%. The cross-validated sensitivity and specificity of DGE-MRI at the optimal cut-off were 76.7% and 87.1%, respectively, for diagnosing HS >or= 5% and 90.9% and 94%, respectively, for diagnosing HS >or= 30%. The cross-validated Bland-Altman 95% limits of agreement between the estimated degree of HS on imaging examinations and the histologic degree of HS, were the narrowest with DGE-MRI, yielding -12.7% to 12.7%. CONCLUSIONS: Among CT, DGE-MRI, (1)H-MRS, and US, DGE-MRI is the most accurate method for the diagnosis and quantitative estimation of HS. Therefore, DGE-MRI may be the preferred imaging examination for the non-invasive assessment of HS.