A multivariate model based on gadoxetic acid-enhanced MRI using Li-RADS v2018 and other imaging features for preoperative prediction of dual­phenotype hepatocellular carcinoma.

OBJECTIVE: To investigate the diagnostic value of liver imaging reporting and data system (LI-RADS) v2018 and other imaging features in dual-phenotype hepatocellular carcinoma (DPHCC), establish a prediagnostic model based on gadoxetic acid-enhanced MRI, and explore the prognostic significance after surgery of the DPHCC. MATERIALS AND METHODS: Preoperative enhanced MRI findings and the clinical and pathological data of patients with surgically confirmed HCC were analysed retrospectively. Image analysis was based on LI-RADS v2018 and other image features. Univariate analysis was used to screen for predictive factors of DPHCC, and multivariate logistic regression analysis was used to determine the predictive factors. A regression diagnostic model was established. Receiver operating characteristic (ROC) curve analysis was used to determine the critical value, area under curve (AUC), and the corresponding 95% confidence interval (95% CI). The diagnostic performance was verified by fivefold cross-validation. Cox regression analysis was used to determine the prognostic factors associated with early recurrence after surgical resection. RESULTS: In total, 158 patients were included, of whom 79 had DPHCC and 79 had non-DPHCC. Multivariate analysis showed that rim arterial phase hyperenhancement (Rim APHE) and targetoid restriction were independent risk factors for DPHCC (P < 0.05). The AUC (95% CI) of the model was 0.862 (0.807-0.918), sensitivity was 81.01%, and specificity was 89.874%. Cox regression analysis showed that DPHCC, microvascular invasion, tumour diameter, and an increase of alpha-fetoprotein were independent factors for recurrence. CONCLUSION: Rim APHE and targetoid restriction were sensitive imaging features of DPHCC before surgery, and the identification of DPHCC has important prognostic significance for early recurrence.

Quantitative assessment of liver function with hepatocyte fraction: Comparison with T1 relaxation-based indices.

PURPOSE: This study aimed to assess the use of hepatocyte fraction in gadoxetic acid-enhanced magnetic resonance imaging (MRI) for quantitatively evaluating the liver function in comparison with T1 relaxation-based indices. METHODS: This retrospective study included 79 patients with chronic liver disease, who were divided into 2 groups based on the results of the indocyanine green retention test (ICG). All patients underwent a gadoxetic acid-enhanced MRI of the liver. Pre- and post-contrast Look-Locker sequences were used 20 min after gadoxetic acid administration to acquire T1 mapping. Two readers independently identified and measured the MRI parameters [five T1 relaxation-based indices (T1pre, T1post, rrT1, R1post/R1pre and ΔR1) and two hepatocyte fraction indices (HeF and KHep)]. An Independent-samples t test was used to compare each parameter for the two groups. Pearson correlation analysis was used to analyze the correction in each parameter and 15-minute ICG retention rate (ICG-R15). Receiver operating characteristic analyses were performed to differentiate the diagnostic performance of each parameter in ICG-R15 ≤ 20 % and ICG-R15 > 20 % groups. RESULTS: T1pre and T1post were significantly lower in the ICG-R15 ≤ 20 % group than in the ICG-R15 > 20 % group (P < 0.05). rrT1, R1post/R1pre, ΔR1, HeF, and KHep were significantly higher in the ICG-R15 ≤ 20 % group than in the ICG-R15 > 20 % group (P < 0.05). The correction coefficients between T1pre, T1post, rrT1, R1post/R1pre, ΔR1, HeF, KHep, and ICG-R15 were 0.343, 0.783, -0.833, -0.781, -0.803, -0.819, and -0.832, respectively. The area under the curves (AUCs) of T1pre, T1post, rrT1, R1post/R1pre, ΔR1, HeF, and KHep in assessing the ICG-R15＞20 % groups were 0.761, 0.945, 0.912, 0.912, 0.948, 0.945, and 0.950, respectively. KHep had the highest AUC, sensitivity, and specificity. CONCLUSION: Hepatocyte fraction based on gadoxetic acid-enhanced T1-mapping MRI is an efficient diagnostic tool for the quantitative evaluation of liver function.

Evaluation of liver function using the hepatocyte enhancement fraction based on gadoxetic acid-enhanced MRI in patients with chronic hepatitis B.

OBJECTIVES: This study aimed to evaluate the feasibility of using the hepatocyte enhancement fraction (HEF) based on gadoxetic acid-enhanced magnetic resonance imaging (MRI) for assessing the liver function in patients with chronic hepatitis B. METHODS: Sixty patients with Child-Pugh grade A (CP-A), 18 with Child-Pugh grade B (CP-B), 2 with Child-Pugh grade C (CP-C), and 20 with normal liver function (NLF) were enrolled. Gadolinium ethoxybenzyldiethy-lenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI was conducted. T1 mapping imaging was performed before and 20 min after Gd-EOB-DTPA administration. The pre- and post-contrast T1 values of the liver (T1pre and T1post), increase in the T1 relaxation rate (ΔR1), rate of decrease in the T1 relaxation time (ΔT1), HEF, and uptake coefficient (K) parameters in the NLF, CP-A, and CP-B + CP-C groups were compared using one-way analysis of variance. The effectiveness of each parameter in differentiating the NLF + CP-A group from the CP-B + CP-C group was evaluated using the receiver operating characteristic (ROC) curve. RESULTS: The HEF, K, ΔT1, and ΔR1 values decreased, while the T1post and T1pre values increased, with the increase in liver function damage. Significant differences in T1post, ΔT1, ΔR1, and HEF were found between different groups, except for the CP-A and NLF groups. However, no significant difference was observed in the T1pre among the three groups. HEF exhibited the largest area under the ROC curve. CONCLUSION: The HEF is an effective method for evaluating liver function in patients with hepatitis B.

Efficient heralding of O-band passively spatial-multiplexed photons for noise-tolerant quantum key distribution.

When implementing O-band quantum key distribution on optical fiber transmission lines carrying C-band data traffic, noise photons that arise from spontaneous Raman scattering or insufficient filtering of the classical data channels could cause the quantum bit-error rate to exceed the security threshold. In this case, a photon heralding scheme may be used to reject the uncorrelated noise photons in order to restore the quantum bit-error rate to a low level. However, the secure key rate would suffer unless one uses a heralded photon source with sufficiently high heralding rate and heralding efficiency. In this work we demonstrate a heralded photon source that has a heralding efficiency that is as high as 74.5%. One disadvantage of a typical heralded photon source is that the long deadtime of the heralding detector results in a significant drop in the heralding rate. To counter this problem, we propose a passively spatial-multiplexed configuration at the heralding arm. Using two heralding detectors in this configuration, we obtain an increase in the heralding rate by 37% and a corresponding increase in the heralded photon detection rate by 16%. We transmit the O-band photons over 10 km of noisy optical fiber to observe the relation between quantum bit-error rate and noise-degraded second-order correlation function of the transmitted photons. The effects of afterpulsing when we shorten the deadtime of the heralding detectors are also observed and discussed.

Transmission of O-band wavelength-division-multiplexed heralded photons over a noise-corrupted optical fiber channel.

We transmitted O-band heralded photons over 10 km of optical fiber in a proof-of-concept experiment demonstrating the feasibility of using heralded photons to improve the noise tolerance of quantum key distribution. In our experiment, the optical fiber channel was corrupted by noise photons to the extent that if we had used an attenuated laser as the photon source, a photon signal-to-noise ratio of < 4.0 at the receiver, corresponding to a quantum bit-error rate of > 10.0%, would have prevented the effective generation of secure keys. Using a photon heralding scheme, the photon signal-to-noise ratio in our experiment was shown to be > 7.8. This corresponds to a quantum bit-error rate of < 5.7%, which is good enough for distilling secure keys. In addition, we showed that it is possible to incorporate wavelength-division-multiplexing into the photon heralding scheme to improve overall key rate. We discussed and clarified the prospects and limitations of the photon heralding scheme for noise-tolerant quantum key distribution.