Xiangdong Hu

HEPATIC PERFUSION PARAMETERS OF CONTRAST-ENHANCED ULTRASONOGRAPHY CORRELATE WITH THE SEVERITY OF CHRONIC LIVER DISEASE

In the study described here, we introduced a new ratio acquired with contrast-enhanced ultrasonography (CEUS): a liver parenchyma blood supply ratio that differentiates arterial and portal phases. Our purpose was to determine whether this ratio and other liver parenchyma perfusion parameters acquired with CEUS can be correlated with the severity of chronic liver disease. Twelve patients with non-cirrhotic chronic liver disease, 35 patients with cirrhosis (child class A: n = 10; child class B: n = 13; child class C: n = 12) and 21 healthy volunteers were examined by CEUS. Time-intensity curves were drawn for regions of interest located in liver parenchyma and right kidney cortex using QLAB quantification software. The arterial and portal phases were differentiated by the time to the maximum enhancement of right kidney and liver parenchyma perfusion data acquired from the time-intensity curves: the intensity of liver parenchyma perfused by hepatic arterial flow (I(ap)), the intensity of total perfusion of liver parenchyma (I(peak)), the intensity of liver parenchyma perfused by portal venous flow (I(pp)) and the ratio of portal perfusion to total perfusion of liver parenchyma expressed by the parameters I(pp)/I(peak), I(peak), I(pp) and I(pp)/I(peak) significantly decreased in patients with cirrhosis and in patients with non-cirrhotic chronic liver disease, whereas Iap increased. The parameters I(pp), I(peak), I(pp)/I(peak) and Iap correlated with the severity of chronic liver disease (r = -0.938, p < 0.001; r = -0.790, p < 0.001; r = -0.931 p < 0.001; r = 0.31, p < 0.05). The diagnostic accuracy rates for cirrhosis expressed as areas under receiver operating characteristic curves were 0.93 for I(peak), 0.98 for I(pp), 0.98 for I(pp)/I(peak), and 0.69 for I(ap). Liver parenchyma perfusion parameters obtained by CEUS were correlated with the severity of chronic liver disease and have the potential to assess cirrhosis non-invasively.

Shear wave elastography results correlate with liver fibrosis histology and liver function reserve

AIM To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg) was given to 12 canines for 24 wk to induce experimental liver fibrosis, with olive oil given to 2 control canines. At 24 wk, liver condition was evaluated using clinical biochemistry assays, SWE imaging, lidocaine metabolite monoethylglycine-xylidide (MEGX) test, and histologic fibrosis grading. Clinical biochemistry assays were performed at the institutional central laboratory for routine liver function evaluation. Liver stiffness was measured in triplicate from three different intercostal spaces and expressed as mean liver stiffness modulus (LSM). Plasma concentrations of lidocaine and its metabolite MEGX were determined using high-performance liquid chromatography repeated in duplicate. Liver biopsy samples were fixed in 10% formaldehyde, and liver fibrosis was graded using the modified histological activity index Knodell score (F0-F4). Correlations among histologic grading, LSM, and MEGX measures were analyzed with the Pearson linear correlation coefficient. RESULTS At 24 wk liver fibrosis histologic grading was as follows: F0, n = 2 (control); F1, n = 0; F2, n = 3; F3, n = 7; and F4, n = 2. SWE LSM was positively correlated with histologic grading (r = 0.835, P < 0.001). Specifically, the F4 group had a significantly higher elastic modulus than the F3, F2, and F0 groups (P = 0.002, P = 0.003, and P = 0.006, respectively), and the F3 group also had a significantly higher modulus than the control F0 group (P = 0.039). LSM was negatively associated with plasma MEGX concentrations at 30 min (r = -0.642; P = 0.013) and 60 min (r = -0.651; P = 0.012), time to ½ of the maximum concentration (r = -0.538; P = 0.047), and the area under the curve (r = -0.636; P = 0.014). Multiple comparisons showed identical differences in these three measures: significantly lower with F4 (P = 0.037) and F3 (P = 0.032) as compared to F0 and significantly lower with F4 as compared to F2 (P = 0.032). CONCLUSION SWE LSM shows a good correlation with histologic fibrosis grading and pharmacologic quantitative liver function reserve in experimental severe fibrosis and cirrhosis.

Contrast-Enhanced Ultrasonography Diagnostic Evaluation of Esophageal Varices in Patients With Cirrhosis.

Abstract The purpose of this study was to clarify the usefulness of contrast-enhanced ultrasonography (CEUS) for the diagnosis of esophageal varices (EVs) in patients with cirrhosis. A total of 81 cases (56 patients with EVs and 25 control subjects without EV) were examined by CEUS and by esophagogastroduodenoscopy. According to the esophagogastroduodenoscopy results, we divided the subjects into 3 groups: G0, G1, and G2. The G0 group had 25 patients who exhibited no liver abnormality other than liver cyst or hemangioma without EVs, G1 comprised 9 patients with small EVs and 13 with medium EVs. G2 was composed of 34 cases of severe EVs. Under CEUS, the following parameters were measured: the thickness of double-layer mucosa and submucosa in the lower esophagus (Tm), the maximum anteroposterior diameter of the lower esophagus (De), and the ratio of Tm to De (Tm/De). Time-intensity curves of the lower esophagus and aorta were drawn using QLAB software. One-factor analysis of variance was used to compare means between the 3 groups. The diagnostic value of CEUS was assessed by receiver operating characteristic curves. Bayes discriminant analysis was adopted for building discriminant equations. Tm, De, Tm/De, Tep, and Iep/Iap were greater in patients with EVs (G1 and G2) than in those without EVs (G0). The Tms for the G0, G1, and G2 groups were 4.16 ± 0.59 mm, 7.06 ± 0.89 mm, and 10.10 ± 1.77 mm (P < 0.01), respectively, with 7.65 mm being the best cutoff value for diagnosing ≥ G2 (sensitivity 96.9%, specificity 90.0%). The area under the receiver operating characteristic curve was 0.987. Three discriminant equations were obtained by Bayes discriminant analysis: y 0 = −6.2 + 2.5Tm, y 1 = −15.1 + 4.1Tm and y 2 = −31.7 + 6.0Tm, respectively. The equations correctly classified 91.7% of cases in the study, making an error rate of 8.3%. Tm attained from CEUS can be a new, convenient, noninvasive parameter for evaluating esophageal varices in patients with liver cirrhosis.

New Noninvasive Assessment of Liver Fibrosis in Chronic Hepatitis B Maximal Accumulative Respiration Strain

Objective. A novel parameter acquired from conventional B‐mode sonographic videos was introduced in this study, and its diagnostic accuracy for evaluation of hepatic fibrosis was investigated. Methods. Twenty‐eight patients with chronic hepatitis B and 8 patients with hepatic cysts in the right lobe (controls) were enrolled. B‐mode sonographic videos of hepatic motion under the ensisternum in the sagittal plane were captured during peaceful breathing. Maximal accumulative respiration strain (MARS) values of hepatic tissue were obtained after image analysis. METAVIR scoring after liver biopsy was considered the standard. First, the relationship between MARS and the fibrotic stage was studied; and second, receiver operating characteristic (ROC) curves were used to assess the accuracy of MARS for evaluation of the fibrotic stage. Results. When the transducer was placed in the sagittal imaging plane under the ensisternum during the whole respiratory period, the hepatic tissue motion was almost in the same plane. The MARS values (mean ± SD) were 29.44% ± 10.44% in the F0 group (no fibrosis; n = 8), 19.30% ± 9.10% in the F1 group (portal fibrosis without septa; n = 8), 18.09% ± 7.36% in the F2–F3 group (portal fibrosis with few septa or numerous septa without cirrhosis; n = 12), and 14.16% ± 4.18% in the F4 group (cirrhosis; n = 8). The Spearman correlation coefficient between MARS and the fibrotic stage was 0.516 (P = .001). The diagnostic accuracy rates, expressed as areas under the ROC curves, were 0.87 for mild fibrosis (F ≥ 1), 0.72 for substantial fibrosis (F ≥ 2), and 0.75 for cirrhosis (F = 4). Conclusions. Maximal accumulative respiration strain attained from B‐mode sonographic videos of hepatic tissue is a new, convenient, economical, and promising noninvasive parameter for assessment of hepatic fibrosis in patients with chronic hepatitis B.

Efficacy of Ablation Therapy for Secondary Hyperparathyroidism by Ultrasound Guided Percutaneous Thermoablation

The objective of this study was to explore the value of ultrasound-guided percutaneous microwave thermoablation to treat secondary hyperparathyroidism (SHPT). One hundred and thirty-eight parathyroid glands from 56 patients with SHPT were ablated in this study. All the parathyroid glands were evaluated by real-time contrast-enhanced ultrasound before, during and after ablation. Changes in serum parathyroid hormone (sPTH) levels were measured before treatment and at 1 h, 1 wk, 1 mo and 6 mo after thermoablation treatment. All 56 cases had a 1-mo follow-up, and 34 cases had a 6-mo follow-up. The sPTH level of the 54 cases 1 mo after ablation was significantly lower than that before (p < 0.05). In the 34 cases that had a 6-mo follow-up, the sPTH levels were also significantly lower at 6 mo after ablation than before (p < 0.05). Bone pain in patients improved post-operatively (p < 0.05), but itchiness and insomnia did not improve (p > 0.05). Ultrasound-guided percutaneous microwave thermoablation is a feasible and effective non-surgical alternative treatment for SHPT patients.

Maximal accumulative respiration strain for the assessment of hepatic fibrosis

Early detection and grading of liver fibrosis are important for the treatment of chronic hepatitis. As the gold standard for the assessment of hepatic fibrosis, liver biopsy is invasive, and may cause hemorrhage and infection. Therefore, it is very important to develop noninvasive clinical methods for fibrosis assessment. In this paper, B-mode videos of the liver during peaceful respiration were acquired from two groups of people (8 healthy volunteers and 7 patients with biopsy-proven grade 4 fibrosis). All the videos were captured from the sagittal plane under the ensisternum where the hepatic tissue motion was almost in the imaging plane. After selecting a region of interest (ROI) in the hepatic tissue, the average strain of the hepatic tissue in the ROI was calculated from each adjacent frames. After that the accumulative strain during the whole respiration cycle was computed. Then the maximal accumulative respiration strain (MARS) during the respiration cycle was obtained. Significant difference between the MARS of these two groups was found. The mean MARS of the healthy group and fibrosis group were 29.45 and 15.19, respectively. The results indicated that the MARS was correlated to the hepatic fibrosis, and might be a potential parameter for hepatic fibrosis assessment.