Correlation of MRI liver volume and doppler sonographic portal hemodynamics with histologic findings in patients with chronic hepatitis C

The prevalence of functional dyspepsia using Rome III questionnaire among chronic hepatitis C patients

Background

Hepatitis C virus (HCV) is a common chronic infection that is widely associated with symptoms of fatigue and abdominal pain. The aim of the present study was to determine the prevalence of functional dyspepsia (FD) among patients with hepatitis C.

Methods

This study included 252 patients with chronic hepatitis C and 150 healthy volunteers. Clinical and laboratory data were recorded for every patient. All patients and controls were administered a questionnaire of FD according to Rome III criteria.

Results

The percentage of patients with FD was significantly higher in patients with chronic HCV than normal controls (65.9 % vs 28.7 %, respectively). In chronic HCV patients, post prandial distention syndrome (PDS) subtype was the predominant type (86.1 %). The percentage of patients with a high fibrosis score (F2–3) and raised ALT were significantly higher in patients with FD than in patients without FD (P < 0.001; P < 0.04; respectively). A multivariate regression analysis revealed a significant association between fibrosis score, BMI and FD

Conclusion

FD is more prevalent in patients with chronic hepatitis C. Obese chronic HCV and those with higher fibrosis scores are more likely to have FD.

Are hepatic portal venous system components distributed equally in the liver? A multidetector computerized tomography study

OBJECTIVE

We aimed to evaluate the relationships between the splenic index, right and left hepatic lobe volumes, diameters of splenic vein (SV), superior mesenteric vein (SMV) and the portal vein (PV) by Multidetector Computerized Tomography (MDCT). We also investigated indirect signs of portal venous flow pattern using these parameters.

MATERIAL AND METHODS

Following their contrast thoracoabdominal and abdominal 64-MDCT examinations, the images of 100 cases (61 males and 39 females) were evaluated retrospectively. For each case, the splenic index, total hepatic volume, left and right hepatic volumes were calculated on the post-contrast portal venous phase (50(th) sec) images. Spearman correlation tests were carried out with the purpose of determining the relationships between the variables. Statistical significance level was set at p<0.005.

RESULTS

A statistically significant relation was demonstrated between the diameter of the SMV and right hepatic lobe volume (p<0.0001), and according to Pearson's correlation analysis, a positive correlation of medium strength (r=0.36) was observed. A positive correlation was demonstrated between the diameter of the splenic vein and left hepatic lobe volume (r=0.36). Statistically significant relation between the diameters of the splenic vein and right hepatic lobe was not observed (p=0.62). A strong correlation between the left hepatic lobe volume and the splenic index (r=0.556) was observed.

CONCLUSION

We observed a positive correlation and a significant relation between the diameter of the SMV and the right hepatic lobe, and a relation between the splenic vein and splenic index and both hepatic lobes. We believe that this situation is related to the streamline flow in the portal vein, and as demonstrated in the literature, the flow in the SMV is directed at the right lobe, whereas the splenic vein empties into the liver homogenously. Our study is the first study in the literature performed by multidetector CT, which is a technique that reveals the relations between the streamline flow in the portal vein, the splenic index and the hepatic lobe volumes.

Does spleen volume play a role in patients with HCV-related chronic hepatitis?

As the lymphotropism of hepatitis C virus (HCV) has already been ascertained, and in the light of the fact that the immune defense system is an organized network composed of functionally interrelated tissues, this study was carried out to verify the possible involvement of spleen in HCV-related chronic hepatitis. In this cross-sectional study we measured spleen longitudinal diameter by ultrasound, beta2-microglobulin serum levels and splenic artery resistivity index (SARI) by Doppler in 51 patients treated with standard combined (Peg-Interferon plus Ribavirin) antiviral therapy. Thirty-three patients (17 females) completed the regimen and were compared to 31 controls (16 females). The mean basal values of spleen longitudinal diameter were higher in patients with chronic hepatitis than in controls, i.e., 116 mm (9.4) versus 102.7 mm (9.3), P = 0.0001. In the same patients a significant trend towards increased spleen longitudinal diameter was found after antiviral therapy, independently of the stage of HCV-related chronic hepatitis. The median values of the beta2-microglobulin concentrations were not significantly higher in the patients with HCV-related chronic hepatitis compared to controls, i.e., 1.3 (0.5-2.6) versus 1 (0.6-1.4), P = 0.16, although during the course of therapy they were significantly increased. SARI values of HCV-related chronic hepatitis patients were different from those of controls, but were unvaried compared to values at the end of treatment. Neither spleen measurements nor serum beta2-microglobulin levels were able to predict therapeutic response to antiviral therapy. A stimulation/expansion of lymphoid tissue was found in patients with HCV-related chronic hepatitis. Such evidence raises the question whether physicians should continue to prescribe antiviral therapy in non-responders and supports the use of a new scheme (SLD plus beta2-MG) to diagnose this ongoing, apparently reversible, but nevertheless dangerous immunologic process.

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.

Pre- and postprandial alterations of portal venous flow: Evaluation with single breath-hold three-dimensional half-fourier fast spin-echo MR imaging and a selective inversion recovery tagging pulse

PURPOSE

To evaluate the influence of food intake on portal flow using unenhanced magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The study population included 29 healthy subjects. A selective inversion recovery tagging pulse was used on the superior mesenteric vein (SMV) and splenic vein (SpV) to study the correlation of tagged blood in the portal vein (PV). MRI was performed before and 60-90 min after a meal.

RESULTS

The flow signal from the SMV increased in 97% of the subjects after the meal. Before the meal the portal flow was dominated by flow from the SpV in 59% of the subjects, while it was dominated by flow from the SMV in 76% of the subjects after the meal. The most common distribution pattern of the flow signal from the SpV before the meal was in the central part of the main PV (55%), while it was in the left side (45%) after the meal. The most common distribution pattern of the flow signal from the SMV was in the bilateral sides of the main PV both before and after the meal (62%).

CONCLUSION

This technique shows potential for evaluating pre- and postprandial alterations of flow from the SpV and SMV in the PV under physiological conditions.

Characteristics of upper abdominal pain in those with chronic liver disease

Chronic hepatitis has many causes. Symptoms include upper abdominal pain. To allow for a better understanding of this pain we compare HCV patients with other liver diseases and normal controls on their reporting of pain over one month and describe associations. A cross-sectional, case control study was performed. Three groups are studied: (1) normal individuals (NC) (N = 64), (2) patients with chronic liver diseases other than HCV (LD) (N = 53), and (3) HCV infection (N = 64). A dyspepsia questionnaire was utilized, which inquired about a one-month symptom presence of upper abdominal pain and associated symptoms. There was a one-month period prevalence of upper abdominal pain of 45.3% in the HCV group vs 32% in the LD and 20.3% in the NC groups (P = 0.01). The LD (22.6%) and HCV (26.6%) groups had markedly more pain that was worsened by eating compared with NC (1.6%) (P = .003). On univariate analysis, when comparing those with upper abdominal pain to those without, there was a lower age (41.3 vs 44.5), a higher BMI (30.3 vs 26), and more symptoms of fatigue, bloating, and pain worsened by eating and early satiety. On multivariate analysis, age < 50 (OR 5.1; CI 1.5-17), BMI > 30 (OR 4.1; CI 1.5-10.9), nausea (OR 4.1; CI 1.6-10.4), and pain with eating (OR 30: CI 6.7-133) predicted upper abdominal pain. In conclusion, upper abdominal pain is more commonly reported over one month in those with chronic liver diseases. That the abdominal pain worsened after meals in liver patients but not in the normal subjects was a surprise. Possible explanations for this finding are offered.

Unbiased estimation of the liver volume by the Cavalieri principle using magnetic resonance images

OBJECTIVE

It is often useful to know the exact volume of the liver, such as in monitoring the effects of a disease, treatment, dieting regime, training program or surgical application. Some non-invasive methodologies have been previously described which estimate the volume of the liver. However, these preliminary techniques need special software or skilled performers and they are not ideal for daily use in clinical practice. Here, we describe a simple, accurate and practical technique for estimating liver volume without changing the routine magnetic resonance imaging scanning procedure.

MATERIALS AND METHODS

In this study, five normal livers, obtained from cadavers, were scanned by 0.5 T MR machine, in horizontal and sagittal planes. The consecutive sections, in 10 mm thickness, were used to estimate the whole volume of the liver by means of the Cavalieri principle. The volume estimations were done by three different performers to evaluate the reproducibility.

RESULTS

There are no statistical differences between the performers and real liver volumes (P > 0.05). There is also high correlation between the estimates of performers and the real liver volume (r = 0.993).

CONCLUSION

We conclude that the combination of MR imaging with the Cavalieri principle is a non-invasive, direct and unbiased technique that can be safely applied to estimate liver volume with a very moderate workload per individual.

Comparison of two volumetric techniques for estimating liver volume using magnetic resonance imaging

PURPOSE

To compare the conventional technique of manual planimetry with the point counting technique for estimating liver volume from magnetic resonance imaging (MRI) data.

MATERIALS AND METHODS

This study comprised abdominal MR examinations of 38 consecutive patients. Evaluation of the images showed that liver size appeared normal in 27 patients and increased in 11. Liver volume was estimated using the techniques of planimetry and point counting. Both techniques were used in combination with the Cavalieri method of modern design stereology. A systematic slice sampling procedure was performed to estimate liver volumes using both volumetric techniques. The point counting technique was optimized by altering the point spacing of the grid. The agreement between the two techniques was found. Measurement repeatability of both volumetric techniques was also evaluated.

RESULTS

Both techniques allowed the same degree of optimization through the procedure of systematic section sampling. The application of a point spacing of 2.5 cm reduced the time measurement by a factor of 3.5 in relation with the time needed with planimetry. An excellent agreement was observed between the two volumetric techniques with mean differences (+/-SD) of 2.4 +/- 41.6 cm(3) and 8.5 +/- 49.8 cm(3) for the patients presenting normal and increased liver sizes, respectively. Both techniques were highly reproducible.

CONCLUSION

The point counting technique could be considered a more efficient approach than planimetry for estimating liver volume from MRI, due to its speed and simplicity.

MR imaging in chronic hepatitis and cirrhosis

The role of magnetic resonance imaging (MRI) in the evaluation of diffuse parenchymal abnormalities of the liver has been expanded by recent technical advances of MR systems as well as the evolution of intravenous contrast media. Currently, MR is undoubtedly the most useful imaging modality for detecting the presence of chronic liver disease. Tailored sequences allow acurate depiction of specific disorders, including steatohepatitis and iron-overload states. Morphologic changes and signal intensity effects not only facilitate the diagnosis of chronic liver disease with MRI but they also help to distinguish between different etiologies, and they assist in staging the histologic severity of certain chronic conditions. Moreover, the faster MRI scanning techniques presently available permit the dynamic assessment of contrast enhancement, which permits improved characterization of focal hepatic lesions, including regenerative nodules, dysplastic nodules, and hepatocellular carcinoma (HCC). Although overlap in MRI findings still may exist among different types of chronic liver disease and among focal liver lesions, familiarity with certain specific imaging features may be diagnostic in the proper clinical setting. Finally, comprehensive MRI examination, including MR angiography and MR cholangiography, is the most sensitive and cost-effective technique for detecting extrahepatic disease, diagnosing vascular disorders, and evaluating the patient before or after liver transplantation. This article focuses on the current role of MR imaging in patients with chronic liver disease. The subjects covered include the detection and characterization of chronic hepatitis and cirrhosis, specific findings seen in steatohepatitis and certain metabolic diseases, the evaluation of extrahepatic vascular complications of cirrhosis, and patient assessment before and after liver transplantation. The characterization of hepatic masses is also included briefly. This subject is covered in greater depth elsewhere in this issue.