Value of Doppler sonography in assessing the progression of chronic viral hepatitis and in the diagnosis and grading of cirrhosis

A systematic review and meta-analysis of portal vein morphometry in pediatric and adult populations: Drawing the line between normal and abnormal findings

PURPOSE

The morphometry of the hepatic portal vein is of clinical importance, particularly in pre-operative assessments, surgical management, and diagnoses of liver conditions. This systematic review and meta-analysis aimed to characterize the morphometry of the normal portal vein in both pediatric and adult patients.

METHODS

The study, conducted using the PRISMA guidelines and registered with PROSPERO, utilized the MEDLINE, EMBASE, SCOPUS and Web of Science databases up to May 2020, and updated to May 2023. All studies reporting extractable data on diameter, length, and cross-sectional area (CSA) of the main, left, and right portal veins (PV, LPV, RPV, respectively) were included. The AQUA Tool was used to assess the quality of the included studies. Data analysis included subgroup analyses based on geographical location, sex, age, and imaging modality.

RESULTS

A total of 122 studies with 11,637 subjects were eligible for inclusion. Overall, the pooled mean diameter of the PV (PVD) was 10.09 mm (95% CI: 9.56-10.62). Significant differences in diameter were found between pediatric (6.60 mm; 95% CI: 5.38-7.82) and adult (10.72 mm; 95% CI: 10.25-11.19) subjects. Additionally, there was a significantly larger PVD measurement from computed tomography (CT) than other imaging modalities: CT, 13.28 mm (95% CI: 11.71-14.84); magnetic resonance imaging (MRI), 10.50 mm (95% CI: 9.35-11.66) and ultrasound (US), 9.81 mm (95% CI: 9.47-10.16). The mean diameters of the LPV and RPV were 8.27 mm (95% CI: 6.78-9.77) and 8.33 mm (95% CI: 6.70-9.95), respectively. Mean PV length in adults is 48.63 mm (95% CI: 35.63-61.64). Mean CSA of the PV was 1.09 cm2.

CONCLUSIONS

The study obtained aim to improve the understanding of portal vein anatomy, especially with relevance to surgical interventions of the liver in both pediatric and adult patients. Measurements from ultrasound imaging closely approximates the generated pooled PVD mean for pediatric and adult patients. CT imaging, however, significantly exceeded the established 13 mm threshold for adults. For pediatric patients, a threshold of 8 mm is proposed as a diagnostic upper limit for a normal PVD. Although not significant, the PVD decreased from the portal confluence towards its bifurcation.

Liver cirrhosis in children - the role of imaging in the diagnostic pathway

Liver cirrhosis in children is a rare disease with multifactorial causes that are distinct from those in adults. Underlying reasons include cholestatic, viral, autoimmune, hereditary, metabolic and cardiac disorders. Early detection of fibrosis is important as clinical stabilization or even reversal of fibrosis can be achieved in some disorders with adequate treatment. This article focuses on the longitudinal evaluation of children with chronic liver disease with noninvasive imaging tools, which play an important role in detecting cirrhosis, defining underlying causes, grading fibrosis and monitoring patients during follow-up. Ultrasound is the primary imaging modality and it is used in a multiparametric fashion. Magnetic resonance imaging and computed tomography are usually applied second line for refined tissue characterization, clarification of nodular lesions and full delineation of abdominal vessels, including portosystemic communications.

Role of portal color Doppler ultrasonography as noninvasive predictive tool for esophageal varices in cirrhotic patients

Background

Esophageal varices (EV) is the most common apprehensive complication of portal hypertension in patients with cirrhotic liver. Guidelines recommend Upper gastro-intestinal endoscopic screening for EV in patients with newly diagnosed chronic cirrhosis (Imperiale et al. in Hepatology 45(4):870–878, 2007). Yet, it is invasive, time consuming and costly. To avoid unnecessary endoscopy, some studies have suggested Doppler ultrasound examination as simple, and noninvasive tool in prediction and assessment of severity of EV (Agha et al. in Dig Dis Sci 54(3):654–660, 2009). Our study was to assess the role of different Doppler indices of portal vein, hepatic and splenic arteries as a noninvasive tool for prediction of esophageal varices in cirrhotic patients.

Results

This prospective case control study was conducted on 100 cirrhotic liver patients and 100 of healthy volunteers as control group. Patients were subjected to clinical examination, upper gastrointestinal tract endoscopy, abdominal ultrasonography with duplex Doppler evaluation of different portal Doppler hemodynamic indices were done for each patient. The results revealed that portal vein diameter, hepatic artery pulsatility index, portal hypertensive index, portal vein flow velocity, portal congestion index have high sensitivity for prediction of EV. However, Splenic artery resistance index, hepatic artery resistance index HARI, liver vascular index and platelet count/spleen diameter have less sensitivity for prediction of EV.

Conclusion

Measuring the portal hemodynamic indices can help physicians as noninvasive predictors of EV in cirrhotic patients to restrict the need for unnecessary endoscopic screening especially when endoscopic facilities are limited.

Application of ultrasound for the diagnosis of cirrhosis/portal hypertension

With advances in technologic approaches in patients with cirrhosis, including the improvement of management, a simple, one-step approach for advanced fibrotic state of the liver is clinically useful. Although refining the diagnosis of cirrhosis to reflect disease heterogeneity is essential, current diagnostic tests have not kept pace with the progression of this new paradigm. There are unmet needs in primary care centers with respect to patients with cirrhosis. Liver biopsy and measurement of hepatic venous pressure gradient in patients with cirrhosis are the gold standards for the estimation of hepatic fibrosis, and they have diagnostic and prognostic value. However, both approaches are invasive and cannot be used repeatedly in clinical practice. Ultrasonography (US) is safe, easy to perform, inexpensive, and yields numerical and accurate results. Conventionally, the size of the liver and spleen, bluntness of the liver edge, nodularity of the liver surface, and coarseness of the liver parenchyma have been known as useful parameters for hepatic fibrosis or portal hypertension (PHT) in chronic liver disease. Additionally, some functional US indices including Doppler and CEUS-based examination have been suggested as promising markers for diagnosing cirrhosis and PHT. Identification of the reproducibility and long-term prognostic value through further investigations can demonstrate the clinical usefulness of functional US indices, which are characterized as quantitative parameters for hepatic fibrosis and PHT.

Hepatic function predictive value of hepatic venous waveform versus portal vein velocity in liver cirrhosis

Background:

This study assessed the hepatic vein waveform (HVW) and mean maximum portal vein velocity (MM-PVV) on Doppler ultrasound in patients with liver cirrhosis (LC) and compared it with that of age and sex-matched controls. It correlated the degree of HVW abnormality and MM-PVV changes with liver function based on Child-Turcotte-Pugh (CTP) to determine which was more predictive of CTP.

Methods:

Sixty patients with LC and 60 healthy controls were consecutively recruited into this study. Each patient was classed based on the CTP system after relevant tests. Doppler evaluation of the hepatic vein (HV) and MM-PVV were performed. HVW obtained was classified either into triphasic, biphasic, or monophasic.

Results:

Sixty cirrhotic and 60 age-matched control subjects aged 19–69 and 18–69 years, respectively, completed this study. All control subjects had a normal HVW pattern while 46 (76.7%) cirrhotic subjects had abnormal HVW (P < 0.001). The MM-PVV was significantly lower in cirrhotic subjects than in controls; 22.8 cm/s versus 33.6 cm/s (P < 0.001). The degree of HVW abnormality among cirrhotics showed a significant positive correlation with CTP (r = 0.283, P = 0.029). MM-PVV on the other hand showed no correlation with CTP class (r = −0.124; P = 0.346). Linear regression showed that HVW was a significant predictor of hepatic dysfunction based on CTP.

Conclusion:

Changes in the waveform pattern of the HVs are a good predictor of the derangement of hepatic function in patients with LC than changes in PVV. HVW pattern could therefore serve as an adjunct to CTP class in hepatic function assessment.

Renal arterial resistance index among subjects with liver cirrhosis in a Nigerian population

PURPOSE

To describe the relationship between renal artery resistance index (RARI) and liver function based on Child-Pugh system among patients with liver cirrhosis (LC) in Southwest Nigeria.

METHODS

About 50 patients with LC and 50 controls were consecutively recruited into this prospective comparative case control study. Each LC patient was classed based on Child-Turcotte-Pugh (CTP) system after relevant tests. Subjects underwent abdominal ultrasonography with triplex Doppler examination of the right kidney to obtain RARI.

RESULTS

About 50 cirrhotic and 50 controls completed the study. Age range of cirrhotic subjects was 19-69 years (mean ± SD = 47.5 ± 13.3) while that of controls was 18-69 years (46.9 ± 15.0). RARI was higher (P = <.001) in patients with LC (0.68) than in controls (0.57). RARI was also significantly higher (P = <.001) in cirrhotic subjects in CTP class C (0.72) than in those in classes B (0.66) and A (0.58). Additionally, RARI showed significant correlation with CTP total score (r = .662; P = <.001), serum bilirubin (r = .297; P = .036), serum albumin (r = -.494; P = <.001), serum sodium (r = -.369; P = .008), Model for End Stage Liver Disease (MELD) score (r = .316; P = .026) and MELD-Na score (r = .470; P = .001). RARI showed no significant relationship with serum creatinine (r = .110; P = .445) and blood urea nitrogen (r = .112; P = .437).

CONCLUSION

Liver cirrhosis is associated with renovascular changes which manifest as increased resistance in the renal arteries. RARI is a useful noninvasive tool for the assessment of these changes and should be done routinely in the evaluation of patients with LC.

Liver Fibrosis Assessment

Early diagnosis of hepatic fibrosis (HF) is pivotal for management to cease progression to cirrhosis and hepatocellular carcinoma. HF is the telltale sign of chronic liver disease, and confirmed by liver biopsy, which is an invasive technique and inclined to sampling errors. The morphologic parameters of cirrhosis are assessed on conventional imaging such as on ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). Newer imaging modalities such as magnetic resonance elastography and US elastography are reliable and accurate. More research studies on novel imaging modalities such as MRI with diffusion weighted imaging, enhancement by hepatobiliary contrast agents, and CT using perfusion are essential for earlier diagnosis, surveillance and accurate management. The purpose of this article is to discuss non-invasive CT, MRI, and US imaging modalities for diagnosis and stratify HF.

The Clinical Importance of Cystatin C and Hepatic Artery Resistive Index in Liver Cirrhosis

Background: Data suggest cystatin C (CysC) levels and hepatic artery resistive index (HARI) correspond to the progression of chronic liver disease. We aimed to evaluate the clinical significance of these parameters in assessment of fibrosis in patients with liver cirrhosis. Methods: The cross-sectional study included 63 patients with liver cirrhosis. A control group consisted of 30 age- and gender-matched healthy persons. Results: We confirmed significantly higher values of CysC in patients with cirrhosis compared to control group (p = 0.036). Average value of HARI in the examined group was increased (0.72 ± 0.06) and there was the statistically significant difference compared to controls (0.66 ± 0.03) (p < 0.001). We found statistically significant correlation between HARI and CysC in the study group. Analyzing the possibility of distinguishing healthy subjects from patients with fibrosis, we have found that the area under the curve is far greater in the HARI index than CysC. Comparison of CysC among Child–Pugh stages and correlation with a model for end-stage liver disease (MELD) score showed statistically significant results. Conclusion: We confirmed HARI is a more accurate parameter than CysC in discriminating healthy subjects from patients with fibrosis, while CysC could be a better indicator of the stage of liver cirrhosis.

Evaluation of portal pressure by doppler ultrasound in patients with cirrhosis before and after simvastatin administration - a randomized controlled trial

Background: Portal hypertension is one of the most frequent complications of cirrhosis. β-adrenergic blockers, with or without organic nitrates, are currently used as hypotensive agents. Statins such as simvastatin seem to be safe for patients with chronic liver diseases and exert multiple pleiotropic actions. This study aimed to assess PTH using Doppler ultrasound in patients with cirrhosis before and after simvastatin administration.

Methods: This randomized controlled clinical trial was conducted on 40 patients with cirrhosis who were randomized into 2 groups: group I included 20 patients with cirrhosis who were administered 20 mg of simvastatin daily for 2 weeks and then 40 mg daily for another 2 weeks, and group II included 20 patients with cirrhosis who did not receive simvastatin as a control group. All patients underwent full clinical examination, laboratory investigations, and abdominal Doppler ultrasound at baseline and after 30 days to evaluate portal vein diameter, blood flow volume, direction and velocity of portal vein blood flow, hepatic artery resistance and pulsatility indices, splenic artery resistance index, portal hypertension index (PHI), liver vascular index, and modified liver vascular index (MLVI).

Results: There was a highly significant decrease in the hepatic artery resistance index  in group I, from 0.785 ± 0.088 to 0.717 ± 0.086 (P < 0.001). There was a significant decrease in the PHI in group I , from 3.915 ± 0.973 m/sec to 3.605 ± 1.168 m/sec (P = 0.024). Additionally, there was a significant increase in the MLVI in group I from 11.540 ± 3.266 cm/sec to 13.305 ± 3.222 cm/sec, an increase of 15.3% from baseline (P = 0.009). No significant adverse effects were detected.

Conclusions: Simvastatin is safe and effective in lowering portal hypertension.

[ClinicalTrials.gov Identifier: NCT02994485]

Evaluation of hepatic fibrosis: a review from the society of abdominal radiology disease focus panel

Hepatic fibrosis is potentially reversible; however early diagnosis is necessary for treatment in order to halt progression to cirrhosis and development of complications including portal hypertension and hepatocellular carcinoma. Morphologic signs of cirrhosis on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) alone are unreliable and are seen with more advanced disease. Newer imaging techniques to diagnose liver fibrosis are reliable and accurate, and include magnetic resonance elastography and US elastography (one-dimensional transient elastography and point shear wave elastography or acoustic radiation force impulse imaging). Research is ongoing with multiple other techniques for the noninvasive diagnosis of hepatic fibrosis, including MRI with diffusion-weighted imaging, hepatobiliary contrast enhancement, and perfusion; CT using perfusion, fractional extracellular space techniques, and dual-energy, contrast-enhanced US, texture analysis in multiple modalities, quantitative mapping, and direct molecular imaging probes. Efforts to advance the noninvasive imaging assessment of hepatic fibrosis will facilitate earlier diagnosis and improve patient monitoring with the goal of preventing the progression to cirrhosis and its complications.

Spleen size in cirrhosis of different etiologies

OBJECTIVES

The purpose of this study was to evaluate the impact of cirrhosis etiology on spleen size as measured by sonography and computed tomography (CT).

METHODS

The spleen images of 139 patients with cirrhosis secondary to alcohol abuse, hepatitis C, or nonalcoholic steatohepatitis were reviewed retrospectively. The maximum diagonal spleen length on a single sonogram and maximum spleen diameter on axial, coronal, or sagittal CT, whichever was largest, was compared among the etiologic groups.

RESULTS

In 127 patients who underwent sonography, the mean spleen size ± SD on sonography in the alcohol group (13.1 ± 2.5 cm) was significantly smaller than in the hepatitis C (15.0 ± 3.4 cm) and nonalcoholic steatohepatitis (15.2 ± 3.0 cm) groups (95% confidence intervals of the mean difference, 0.6 to 3.3 and 0.8 to 3.4 cm, respectively). In 87 patients who underwent CT, the mean spleen size on CT in the alcohol group (14.0 ± 2.7 cm) was smaller than in the hepatitis C (15.9 ± 3.4 cm) and nonalcoholic steatohepatitis (15.5 ± 3.6 cm) groups, but the difference was not statistically significant. The spleen sizes on both sonography and CT in 79 patients were strongly correlated (r = 0.88; P < .0001).

CONCLUSIONS

Spleen size in patients with cirrhosis varies by the etiology of the disease. Therefore, to apply spleen size as a diagnostic or prognostic criterion in this context, it is important to recognize that cutoff values derived from spleen size in one etiologic group may not produce the same results when extrapolated to another etiologic group.

Latest developments in the imaging of fibrotic liver disease

According to the World Health Organization, liver cirrhosis accounted for 1.8% of all deaths in Europe, causing about 170,000 deaths per year. Approximately 29 million persons in the EU suffer from chronic liver disease and this trend is on the rise. Liver disease is the EU's fifth most common cause of death accounting for at least one in six deaths. Early detection and monitoring of fibrosis has the potential to direct management of these chronic liver diseases and avert morbidity and mortality. Although the available techniques are in their infancy and the very early stages of fibrosis are difficult to detect, there have been significant advances in imaging over the last decade that has resulted in the use of these new imaging techniques being introduced into the patient pathway. This review explores the accuracies of these imaging techniques, their role in the management of patients, and the potential for the future.

Preoperative assessment of postoperative liver function: the importance of residual liver volume

An inadequate volume of future liver remnant (FLR) remains an absolute contraindication to liver resection. FLR measurement correlates with surgical outcome and is fundamental to identify those patients that may benefit from portal vein embolization (PVE) and to assess the liver volume change following embolization. In order to minimize the risk of postoperative liver failure, preoperative analysis of FLR must be included in the surgical planning of every major liver resection. The aims of this review are to describe the use of preoperative volumetric analysis in modern liver surgery and indications for PVE.

Evaluation of hepatic tissue blood flow using xenon computed tomography with fibrosis progression in nonalcoholic fatty liver disease: comparison with chronic hepatitis C

AIMS

The present study evaluated the utility of xenon computed tomography (Xe-CT) as a noninvasive diagnostic procedure for the measurement of hepatic tissue blood flow (TBF) in patients with nonalcoholic fatty liver disease (NAFLD) or chronic hepatitis C (CH-C).

METHODS

Xe-CT was performed in 93 patients with NAFLD and in 109 patients with CH-C. Subjects were classified into one of three groups, based on fibrosis stage: group 1, no bridging fibrosis; group 2, bridging fibrosis; and group 3, liver cirrhosis. Correlations between hepatic TBFs in each fibrosis stage were examined.

RESULTS

In group 1, portal venous TBF (PVTBF), hepatic arterial (HATBF), and total hepatic TBF (THTBF) were significantly lower in patients with in nonalcoholic steatohepatitis (NASH) than in those with CH-C (p < 0.001, p < 0.05, p < 0.001, respectively). In group 2, PVTBF and THTBF were significantly lower in patients with in NASH than in those with CH-C (p < 0.001, p < 0.05, respectively). In group 3, hepatic TBFs were not significantly different when comparing patients with NASH and those with CH-C.

CONCLUSIONS

PVTBF decreased due to fat infiltration. Therefore, hemodynamic changes occur relatively earlier in NAFLD than in CH-C. Patients with NASH should be monitored carefully for portal hypertensive complications in the early fibrosis stage.

Hepatic artery Doppler indices in children with extra hepatic portal vein obstruction

Doppler measurement provides information on the hemodynamics in the hepatic artery and the portal venous system.

AIM

To study the hepatic artery hemodynamics in children with extra hepatic portal vein obstruction.

MATERIALS AND METHODS

Hepatic artery indices were studied using Doppler indices in 15 children (<12 years) with extra hepatic portal hypertension (EHPVO) and obliterated esophageal varices. The hepatic artery resistive index, the arterial acceleration time and the acceleration index were used to determine the flow pattern within the hepatic artery. Controls were 15 healthy age-sex matched children, belonging to the same socioeconomic strata in absence of liver disease.

RESULTS

The mean age of the children was 8.43 ± 3.2 years and male female ratio was 4:1. All the children had obliterated esophageal varices. The hepatic artery resistive index in the children with EHPVO was normal and similar to controls. The hepatic arterial early systolic acceleration index was significantly higher in cases compared to controls (436 ± 290 vs 214 ± 100; P value <0.004). The hepatic arterial acceleration time though low in the cases (86 ± 35 cm/s) was not statistically different from the controls (128 ± 14 cm/s).

CONCLUSION

There was a significant increase in hepatic arterial early systolic acceleration in children with chronic EHPVO. The latter may be responsible for an increase in hepatic arterial in flow velocity in a slow flow system despite a normal resistive index.

A prospective experimental study of liver fibrosis with ultrasound and its correlation with hepatic reserve function and hemodynamics

Background

Progressive hepatic fibrosis is the eventual cause of liver cirrhosis. Doppler ultrasound has been used to detect hemodynamic changes that are known to be present during the pre-cirrhotic stages of hepatic fibrogenesis. However, the relationship between the Doppler ultrasound parameters and the impairment of the liver function has not been fully investigated. The purpose of this study was to explore the hepatic function reserve and its relationship with the hepatic hemodynamics in a rabbit model of liver fibrosis using Doppler ultrasound.

Methods

A prospective study was performed. Sixty healthy New Zealand rabbits were included in this study. Eleven of them served as controls and were normally fed and provided with water drink; the rest of 49 rabbits that served as fibrosis group were normally fed but provided with 1.2 g/L of thioacetamide to create liver fibrosis model. Doppler measurements were performed in the portal trunk, proper hepatic artery and proper splenic artery. The hepatic circulation index (HCI) was calculated. Hepatic function reverse was evaluated by measuring the indocyanine green clearance and retention rate at 15 min (ICG R15) test. Portal venous pressure (PVP) was measured using the portal vein punctuation equipment.

Results

HCI was significantly decreased and PVP increased in the advanced fibrotic stage (F4) compared to mild and moderate fibrotic stage (F1-3), respectively (p<0.05). PVP and ICG R15 in the fibrotic group were significantly higher than that in the control group (ICG: 0.209±0.086 vs. 0.093±0.023, p<0.01). Within the fibrotic groups, PVP was higher in advanced fibrotic stage (F4) than those in mild (F1-2) or moderate (F3) fibrotic stages (p<0.05). Both HCI and PVP correlated well with ICG R15 (r = −0.890, and r = 0.780, p <0.01).

Conclusions

Hepatic function reserve closely relates to the hepatic hemodynamics in the rabbit model of liver fibrosis. Doppler Ultrasound could be reliably used to assess the hepatic function reserve and hemodynamic changes in different stages of liver fibrosis.

Non-invasive assessment of fibrosis using color Doppler ultrasound in patients with hepatitis C virus in the Amazon rainforest, Brazil

The purpose of this study was to correlate morphologic and hemodynamic Doppler ultrasound findings as indicators of the degree of inflammation and fibrosis and to diagnose chronic vital hepatitis complications and progression. A prospective, descriptive study of a case series was conducted that analyzed Doppler ultrasound images of the liver and portal system and used the portal vein congestion index, hepatic and splenic artery impedance indices, and the liver vascular index. Of 50 patients positive for antibodies against hepatitis C virus, morphologic changes highlighted increased hepatic parenchyma echogenicity in 24%, and increased gall blander echogenicity and wall thickness in 4%. The most common hemodynamic changes observed were reduced flow velocity in the portal vein trunk in 26%, congestion index changes in 12%, liver vascular index changes in 16%, and splenic and hepatic artery impedance index changes in 14%. These indices were shown to be associated with alanine aminotransferase levels, which suggested that they are important liver damage indicators in the early phase of infection with hepatitis C virus.

Relationship between hepatic haemodynamics assessed by Doppler ultrasound and liver stiffness

AIM

We tested the relationship between hepatic haemodynamics assessed by Doppler ultrasonography and liver stiffness assessed by Transient Elastography in hepatitis C related chronic liver disease.

METHODS

Three liver Doppler ultrasound parameters (hepatic artery resistance index, splenic artery resistance index and waveform pattern in hepatic veins) and liver stiffness measured by Transient Elastography were analysed in one hundred consecutive patients affected by hepatitis C related chronic liver disease.

RESULTS

Hepatic and splenic arteries resistance indexes correlate significantly (p<0.0001 for both) with liver stiffness. A hepatic artery resistance index cut-off value of 0.64 provided sensitivity and specificity respectively of 84.4% and 69.1% for predicting liver stiffness ≤or >13 kPa, whereas a splenic artery resistance index cut-off value of 0.56 provided sensitivity and specificity respectively of 81.3% and 48.5%. The coincidental finding of both resistance indexes above the respective cut-off values showed a good accuracy in identifying patients with liver stiffness values >13 kPa (accuracy=78%, +LR=2.90, -LR=0.31). A significant difference in liver stiffness values was evident between patients with triphasic and bi- or monophasic waveform pattern (p=0.005).

CONCLUSIONS

Hepatic and splenic arteries resistance indexes and the hepatic veins waveform pattern assessed by Doppler ultrasound may provide information similar to that of Transient Elastography in hepatitis C related chronic liver disease.

Can imaging modalities diagnose and stage hepatic fibrosis and cirrhosis accurately?

The accurate diagnosis and staging of hepatic fibrosis is crucial for prognosis and treatment of liver disease. The current gold standard, liver biopsy, cannot be used for population-based screening, and has well known drawbacks if used for monitoring of disease progression or treatment success. Our objective was to assess performance and promise of radiologic modalities and techniques as alternative, noninvasive assessment of hepatic fibrosis. A systematic review was conducted. Six hundred twenty-eight studies were identified via electronic search. One hundred fifty-three papers were reviewed. Most described techniques that could differentiate between cirrhosis or severe fibrosis and normal liver. Accurate staging of fibrosis or diagnosis of mild fibrosis was often not achievable. Ultrasonography is the most common modality used in the diagnosis and staging of hepatic fibrosis. Elastographic measurements, either ultrasonography-based or magnetic resonance-based, and magnetic resonance diffusion weighted imaging, show the most promise for accurate staging of hepatic fibrosis. Most currently available imaging techniques can detect cirrhosis or significant fibrosis reasonably accurately. However, to date only magnetic resonance elastography has been able to stage fibrosis or diagnose mild disease. Utrasonographic elastography and magnetic resonance diffusion weighted appear next most promising.

Abnormality of the hepatic vein waveforms in cirrhotic patients with portal hypertension and its prognostic implications

BACKGROUND AND AIM

We investigated the prognostic significance of changes in the Doppler hepatic vein (HV) waveforms in cirrhotic patients with portal hypertension and the mechanisms of these changes.

METHODS

A total of 103 consecutive patients were included in this study and their HV waveforms were classified into four types: type I, triphasic waveform; type II, biphasic waveform; type III, biphasic waveform with reduced phasic oscillations; and type IV, a flat waveform.

RESULTS

Type I was observed in 34, type II in 40, type III in 23, and type IV in six patients. The 5-year survival rates were 90%, 89%, 41%, and 0% in type I, II, III, and IV, respectively. Five variables including the Child-Pugh score, albumin, bilirubin, ascites, and HV waveform significantly correlated with the survival in a univariate analysis. A multivariate analysis only identified the HV waveform (type III and IV) to be an independent prognostic value. Even in Child-Pugh class B patients, the 5-year survival rate for type III or IV was as poor as 26% in comparison to 92% for type I or II. In contrast, in Child-Pugh class C patients, the 5-year survival rate for type I or II was as good as 63% in comparison to 25% for type III or IV. Furthermore, the changes in HV waveforms correlated with the extent of hepatic fibrosis, the increase in portal perfusion per liver volume, or the decrease in portal vascular resistance.

CONCLUSIONS

Analyzing the HV waveforms was thus found to be a simple method for accurately assessing the prognosis in cirrhotic patients with portal hypertension.

Resistance index in mediastinal lymph nodes: a feasibility study

OBJECTIVE

The purpose of this study was to determine the range of Doppler ultrasonographic measurements of the resistance index in presumed normal mediastinal lymph node arteries.

METHODS

Consecutive patients referred for bronchoscopy for various indications and normal CT findings in the mediastinum were included. The resistance index (RI) in mediastinal lymph node arteries was examined with Color Doppler ultrasonography. The peak systolic velocity (PSV) and the end-diastolic velocity were measured, which allowed for calculation of the resistance indices in different lymph node stations and in each lymph node artery.

RESULTS

Eighty-nine patients (32 female; 57 male; mean age, 42.2 years) were examined, and of these, 50 patients (24 female; 36 male; mean age, 44.7 years) had measurable RIs. PSV and ESV were measured in all visible nodes (n = 196) and an interpretable value was obtained in 127 nodes (2.5 nodes per patient.). The median PSV was 15.6 cm/s (range, 8.9-23.2 cm/s, SD +/- 2.6, 25-75% percentile 13.8-17.5), and the median end-diastolic velocity was 5.8 cm/s (range, 3.6-11.4 cm/s, SD 1.15 cm/s, 25-75% percentile 5.1-6.3). The median RI values for arteries were 0.63 (range, 0.52-0.75, SD 0.04, 25-75% percentile 0.6-0.64) respectively. The Doppler measurements lasted on average 4.3 minutes and no complications were seen.

CONCLUSION

Color Doppler ultrasonography allows for quantification of velocities like PSV and ESV in mediastinal lymph node arteries, which in turn allow calculation of a resistance index. Knowledge of the resistance index's normal range (which describes the resistance of the blood flow within the lumen of the lymph node artery) may be a useful adjunct to the ultrasonic assessment of the mediastinum.

Hepatitis C virus reinfection in liver transplant patients: evaluation of liver damage progression with echo-color Doppler

Liver transplant recipients are a model of rapid progression of hepatitis C virus (HCV)-related liver disease, from normal to cirrhosis. The aim of the study was the analysis of the relationship between portohepatic hemodynamics and modification in liver histology during the progression of HCV liver disease after transplant. Patients transplanted for HCV cirrhosis were considered for the study. At least every 6-12 months, the portal blood flow velocity, hepatic and splenic pulsatility indices, and a portal hypertensive index (obtained from the combination of the portal blood velocity and splenic pulsatility index) were measured with echo-Doppler. Liver biopsy was performed whenever necessary. The time course of echo-Doppler parameters during the histological progression of the liver disease was analyzed. Posttransplant patients without HCV were included as controls. Forty-nine patients with histology-proven relapse of HCV hepatitis were included in the study. At the onset of recurrent hepatitis, the portal blood flow velocity significantly decreased (P < 0.001), and the splenic pulsatility index increased (P = 0.020), whereas the hepatic pulsatility index remained unchanged. In the following years, in addition to a further slight decrease in the portal blood velocity (P = 0.027), a progressive increase in the hepatic and splenic pulsatility indices was also detected (P = 0.009 and P < 0.0001, respectively). The portal hypertensive index steadily increased with the progression of the disease and was related to the degree of liver fibrosis. In conclusion, the information obtainable from splanchnic Doppler parameters can be used to monitor the progression of liver fibrosis in transplant patients with HCV reinfection.

Assessment of hepatic functional reserve by cirrhosis grading and liver volume measurement using CT

AIM: To explore a method for quantitative assessment of hepatic functional reserve by combining computed tomography (CT) volumetry with CT grading of liver cirrhosis before liver resection in patients with hepatocellular carcinoma.

METHODS: CT images of 55 patients undergoing liver resection were studied prospectively. The degree of liver cirrhosis was referred as "CT grade" and the percentage of remnant liver volume (PRLV) [PRLV = predicted RLV/predicted total liver volume (PTLV) × 100%; PTLV (mL) = 121.75 + 16.49 × body mass (kg)] were calculated by adding slice by slice of CT liver images. The postoperative RLV, pathologic stages of liver fibrosis in non-tumor area and survival time in these cases were analyzed.

RESULTS: There was a significant difference in survival time between the group with PRLV ≤ 50% and the group with PRLV > 50% (χ² = 4.988, P = 0.026), and between the group with CT grade 0/1 and the group with CT grade 2/3 (χ² = 5.429, P = 0.026). With combination of the both parameters, an oblique line was identified according to the distribution of 32 survivors versus 23 deceased subjects. The mortality rate above the line was 7.1% (1/14), and that below the line was 53.7% (22/41), indicating a significant difference between the two rates (χ² = 9.281, P = 0.002, P < 0.05).

CONCLUSION: PRLV and CT grades are significantly correlated with hepatic functional reserve. The predicted line using these two parameters is useful in candidates undergoing liver resection for judging hepatic functional reserve.

Clinical evaluation of magnetic resonance imaging flowmetry of portal and hepatic veins in patients following hepatectomy

BACKGROUND

Hepatic blood flow was associated with degree of hepatic damage. Measurements of blood flow using ultrasonography (US) may vary due to any observer's and patient's conditions. The utility of magnetic resonance imaging (MRI) flowmetry in portal and hepatic veins was assessed.

PATIENTS AND METHODS

Using the phase-contrast method, the mean flow velocity of portal (PVF) and hepatic vein (HVF) were determined by MRI and US in 75 consecutive patients with liver diseases, including 58 patients undergoing hepatectomy. The correlations between these parameters and clinicopathological findings were examined.

RESULTS

PVF and HVF measured by MRI flowmetry were 12.8+/-4.5 and 14.7+/-5.3 cm/s, respectively. There was no significant correlation of both flows between MRI and US. PVF correlated significantly with portal pressure (r = -0.722; P < 0.05). There was a negative correlation between HVF and histological activity index score (r = -0.366; P < 0.05). PVF and HVF were lower in patients with cirrhosis and higher staging score (2-4) and PVF was lower in patients with higher grading score (2-3; P < 0.05). PVF and HVF were not significantly associated with postoperative complications.

CONCLUSIONS

Our results suggest that MRI flowmetry is a potentially useful tool for measurement of hepatic blood flow and recommend its use for estimation of liver cirrhosis-associated impairment.