Shigeki Ichimura

Analysis of intrahepatic vascular morphological changes of chronic liver disease for assessment of liver fibrosis stages by micro-flow imaging with contrast-enhanced ultrasound: preliminary experience

ObjectiveTo assess morphological vascular changes due to an increase in liver fibrosis by using micro-flow imaging (MFI) of contrast-enhanced ultrasound.MethodsMFI was performed in 47 patients who underwent liver biopsy, and in 10 normal cases. For 27/57 cases, we performed MFI twice in order to assess the reproducibility of the examination, thus yielding a total of 84 examinations. Seven physicians interpreted each case individually by assigning confidence levels for the presence or absence of three imaging features that were related to alteration of portal vein morphology: angle widening, tapering/interruption and tortuosity.ResultsPearson’s correlation coefficient between the average rating scores based on tortuosity and the histological fibrosis stage was 0.806 (p < 0.001). The diagnostic accuracy of the average area under the ROC curve, which was estimated by use of the confidence levels of tapering/interruption, tortuosity and angle widening, was 0.964 for F1 vs. F2–4, 0.968 for F1–2 vs. F3–4 and 0.910 for F1–3 vs. F4. The average correlation coefficient between the ratings on different images from the same patients was 0.838.ConclusionAssessment of morphological intrahepatic vascular changes on MFI may be useful for grading liver fibrosis.

Flexible imaging color enhancement improves visibility of transnasal endoscopic images in diagnosing esophageal varices: a multicenter prospective blinded study.

To clarify the usefulness of transnasal esophagogastroduodenoscope (N‐EGD) with all flexible imaging color enhancement (FICE) patterns (0–9) for the diagnosis of esophageal varices (EV).

Usefulness of Transnasal Argon Plasma Coagulation for Esophageal Varices Compared with the Peroral Method: A Randomized and Prospective Clinical Study

Background: Argon plasma coagulation (APC) is very useful as a consolidation treatment for reducing the recurrence of esophageal varices (EVs). However, repeated sedation in endoscopic treatment has the risk of prolonging hepatic encephalopathy and affects the respiratory state of liver cirrhosis (LC) patients, in whom pulmonary arteriovenous shunts are observed. We evaluated prospectively whether transnasal endoscopic APC without sedation is more effective than peroral endoscopic APC with sedation. Patients and Methods: LC patients (n = 101), treated by endoscopic injection sclerotherapy to eradicate EVs, were randomly divided into a transnasal APC group (n = 50) and a peroral APC group (n = 51). The primary efficacy endpoint was the cumulative recurrence rate of EVs. The secondary endpoints were blood pressure (BP), heart rate, oxygen saturation during APC and complications. Results: There was no significant difference in the cumulative recurrence rate of EVs at 36 months between the transnasal APC and peroral APC groups (35.0 vs. 40.8%, p = 0.39, log-rank test), indicating that transnasal APC is not inferior to peroral APC. The transnasal APC group showed more stable intraoperative BP and oxygen saturation values, and a lower incidence of epigastralgia (56.0 vs. 74.5%, p = 0.04). Conclusion: The efficacy of reducing the recurrence of EVs in the transnasal APC group was not significantly different from that in the peroral APC group. Transnasal APC caused less distress and required no sedation. Therefore, this method was more advantageous for LC patients at risk of suffering from prolongation of hepatic encephalopathy.

Elucidation of Idiopathic Portal Hypertension Based on Liver and Spleen Stiffness Measurements by Virtual Touch Tissue Quantification and Peripheral Blood CD4+ CD25+ T Cytometry

[Introduction] Virtual Touch Tissue Quantification (VTTQ) is an ultrasound technique to quantify tissue stiffness based on measurement of the propagation velocity of elastic shearwaves (Vs) generated by acoustic radiation force impulses that cause tissue displacements. [Objective] To explore the usefulness of liver and spleen stiffness measurements by VTTQ for diagnostic differentiation between idiopathic portal hypertension (IPH) and portal hypertension caused by liver cirrhosis (LC). [Subjects] Thirteen patients with histologically diagnosed IPH and 18 patients with histologically diagnosed LC were recruited for this study. Eight normal subjects (NC) and 7 patients with chronic hepatitis (CH) were also included. [Methods] With the region of interest (ROI) set at a 3-cm depth from the body surface, the mean of 5 successful Vs measurements of the liver and spleen in each patient was determined. The percentage of peripheral blood CD4+ CD25+ T cells (Tregs) in the LC cases and IPH cases was analyzed by FACS, and the size of the spleen (SI) was also measured. [Results] The measured stiffness of the liver (NC: CH: LC: IPH = 1.14: 1.40: 2.50: 1.56 m/s) was greater in the LC patients (p < 0.001), and that of the spleen (2.03: 2.30: 3.12: 3.90) was greater in the patients with IPH (p < 0.001). Making each ROC curve, we set the cut-off values of liver stiffness by VTTQ as follows (CH: LC: IPH = 1.14: 1.54: 1.23 m/s). The sensitivities were (89.5: 94.7: 89.5%) and the specificities were (62.5: 100.0: 75.0%). Meanwhile, setting the cut-off values of spleen stiffness as follows (CH: LC: IPH = 2.44: 2.61: 2.88 m/s), the sensitivities were (66.7: 90.5: 90.5%) and the specificities were (87.5: 100.0: 100.0%). The stiffness measurements of both liver and spleen were proved to be useful in diagnosis. Furthermore, a lower peripheral blood Tregs frequency [(LC: IPH) = (19.0: 11.6%)] (p < 0.001) and a larger SI (22.5: 44.5) (p < 0.001) were recorded in the IPH patients. [Discussion] The IPH patient group showed a lower liver stiffness relative to the LC group and comparable liver stiffness to that in the CH group. Stiffness of the spleen, nevertheless, was markedly higher in the IPH group; thus, stiffness measurements of both the liver and spleen allowed ready diagnostic differentiation between portal hypertension associated with LC and IPH. The increased splenic stiffness with splenomegaly in IPH was considered to be attributable to a state of enhanced immune functions when viewed with reference to the reduced percentage of peripheral blood Tregs.