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101.

Objective

We aimed to develop and assess the efficacy of a liver function index that combines liver enhancement and liver volume to standard liver volume (LV/SLV) ratio on gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI.

Methods

In all, 111 patients underwent a Gd-EOB-DTPA-enhanced MRI, including T1 mapping, before and 20 min after Gd-EOB-DTPA administration. We calculated the following Gd-EOB-DTPA-enhanced MRI-based liver function indices: relative enhancement of the liver, corrected enhancement of the liver-to-spleen ratio, LSC_N20, increase rate of the liver-to-muscle ratio, reduction rate of T1 relaxation time of the liver, ΔR1 of the liver and K Hep; the indices were multiplied by the LV/SLV ratio. We calculated the correlations between an indocyanine green (ICG) clearance and the Gd-EOB-DTPA-enhanced MRI-based liver function indices multiplied by the LV/SLV ratio, by using Pearson correlation analysis.

Results

There were significant correlations between all Gd-EOB-DTPA-enhanced MRI-based liver function indices and ICG clearance (r?=??0.354 to ?0.574, P?<?0.001). All Gd-EOB-DTPA-enhanced MRI-based liver function indices multiplied by the LV/SLV ratio (r?=??0.394 to ?0.700, P?<?0.001) were more strongly correlated with the ICG clearance than those without multiplication by the LV/SLV ratio.

Conclusions

Gd-EOB-DTPA-enhanced MRI-based liver function indices that combine liver enhancement and the LV/SLV ratio may more reliably estimate liver function.

Key points

? Gd-EOB-DTPA-enhanced MRI is useful for assessing liver function. ? Liver enhancement on Gd-EOB-DTPA-enhanced MRI correlates with indocyanine green (ICG) clearance. ? Liver volume to standard liver volume (LV/SLV) ratio correlates with ICG clearance. ? Liver enhancement and LV/SLV ratio help to estimate liver function.  相似文献   
102.
AIM:To clarify features of hepatic hemangiomas on gadolinium-ethoxybenzyl-diethylenetriaminpentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) compared with enhanced computed tomography (CT). METHODS:Twenty-six patients with 61 hepatic hem- angiomas who underwent both Gd-EOB-DTPA-enhanced MRI and enhanced CT were retrospectively reviewed. Hemangioma appearances (presence of peripheral nodular enhancement, central nodular enhancement, diffuse homogenous enhancement, and arterioportal shunt during the arterial phase, fill-in enhancement during the portal venous phase, and prolonged enhancement during the equilibrium phase) on Gd-EOB-DTPA-enhanced MRI and enhanced CT were evaluated.The degree of contrast enhancement at the enhancing portion within the hemangioma was visually assessed using a five-point scale during each phase. For quantitative analysis, the tumor-muscle signal intensity ratio (SIR), the liver-muscle SIR, and the attenuation value of the tumor and liver parenchyma were calculated. The McNemar test and the Wilcoxon's signed rank test were used to assess the significance of differences in the appearances of hemangiomas and in the visual grade of tumor contrast enhancement between Gd-EOB-DTPA-enhanced MRI and enhanced CT. RESULTS:There was no significant difference between Gd-EOB-DTPA-enhanced MRI and enhanced CT in the presence of peripheral nodular enhancement (85% vs 82%), central nodular enhancement (3% vs 3%), diffuse enhancement (11% vs 16%), or arterioportal shunt (23% vs 34%) during arterial phase, or fill-in enhancement (79% vs 80%) during portal venous phase. Prolonged enhancement during equilibrium phase was observed less frequently on Gd-EOB-DTPA-enhanced MRI than on enhanced CT (52% vs 100%, P 0.001). On visual inspection, there was significantly less contrast enhancement of the enhancing portion on Gd-EOB-DTPA-enhanced MRI than on enhanced CT during the arterial (3.94 ± 0.98 vs 4.57 ± 0.64, respectively, P 0.001), portal venous (3.72 ± 0.82 vs 4.36 ± 0.53, respectively, P 0.001), and equilibrium phases (2.01 ± 0.95 vs 4.04 ± 0.51, respectively, P 0.001). In the quantitative analysis, the tumor-muscle SIR and the liver-muscle SIR observed with Gd-EOB-DTPA-enhanced MRI were 0.80 ± 0.24 and 1.28 ± 0.33 precontrast, 1.92 ± 0.58 and 1.57 ± 0.55 during the arterial phase, 1.87 ± 0.44 and 1.73 ± 0.39 during the portal venous phase, 1.63 ± 0.41 and 1.78 ± 0.39 during the equilibrium phase, and 1.10 ± 0.43 and 1.92 ± 0.50 during the hepatobiliary phase, respectively. The attenuation values in the tumor and liver parenchyma observed with enhanced CT were 40.60 ± 8.78 and 53.78 ± 7.37 precontrast, 172.66 ± 73.89 and 92.76 ± 17.92 during the arterial phase, 152.76 ± 35.73 and 120.12 ± 18.02 during the portal venous phase, and 108.74 ± 18.70 and 89.04 ± 7.25 during the equilibrium phase, respectively. Hemangiomas demonstrated peak enhancement during the arterial phase, and both the SIR with Gd-EOB-DTPA-enhanced MRI and the attenuation value with enhanced CT decreased with time. The SIR of hemangiomas was lower than that of liver parenchyma during the equilibrium and hepatobiliary phases on Gd-EOB-DTPA-enhanced MRI. However, the attenuation of hemangiomas after contrast injection was higher than that of liver parenchyma during all phases of enhanced CT. CONCLUSION:Prolonged enhancement during the equilibrium phase was observed less frequently on Gd-EOB-DTPA-enhanced MRI than enhanced CT, which may exacerbate differentiating between hemangiomas and malignant tumors.  相似文献   
103.

Purpose  

Liver demonstrates a heterogeneous 18F fluoro-2-deoxy-d-glucose (18F-FDG) uptake pattern and sometimes shows an abnormally increased uptake even when there is no malignant tissue. The aim of this study was to evaluate the relationships of liver 18F-FDG uptake as related to physical factors, fatty liver, blood glucose (BG), and other biochemical data.  相似文献   
104.
Smoking is implicated in chronic obstructive pulmonary disease (COPD) and hyperhomocysteinemia. To elucidate the role of hyperhomocysteinemia in COPD, we examined the relationship between plasma total homocysteine (tHcy) and spirometric declines in patients with COPD. We recruited 7 male never-smokers, 16 male control smokers, and 24 male patients with COPD. We investigated whether or not smoking might induce hyperhomocysteinemia in subjects predisposed to COPD, and then prospectively examined the relationship between plasma tHcy concentration and annual decline in FEV(1.0) in the COPD group. We found that plasma tHcy concentrations declined among groups in the following order: COPD group > control group > never-smoker group. Furthermore, plasma tHcy concentrations in the COPD group were significantly correlated with %FEV(1.0) (r(s) = 0.46). Also, COPD patients with severe airflow limitation showed a significant decrease in PaO2, which might be involved in the decreased tHcy in those patients. The prospective analysis revealed that plasma tHcy concentration, but not a history of smoking, were significantly correlated with the annual decline in FEV(1.0) calculated by the difference in FEV(1.0) between the first examination and an examination the following year (r(s) = 0.40). The present study suggests that smoking might increase plasma tHcy concentrations, leading to spirometric declines in subjects predisposed to COPD.  相似文献   
105.
106.
The case of a 29-year-old man who had osteochondritis dissecans on the medial aspect of the humeral head is reported. Repetitive micro-trauma at a low elevated arm position was thought to have induced the osteochondral lesion.  相似文献   
107.
108.
Abstract: Adrenocortical stimulation with ACTH both in the morning (M-test) and in the evening (Etest) and the dexamethasone suppression test were carried out in patients suffering from endogenous depression (DEP) and normal controls (NOR). A greater cortisol release in DEP was recognized than in NOR in the M-test, an earlier peak response of DEP was shown in the M-test than in the Etest, and a lack of association between hypersecretion of cortisol during depression and cortisol output after ACTH administration was noted. These findings, together with the results of DST, suggest that excessive activity of the hypothalamic-pituitary-adrenal (HPA) axis in depression may result, partly, from adrenocortical hyperresponsiveness.  相似文献   
109.
110.
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