Hepatic Perfusion Disorders Research Articles

Quantification of Liver Fat Content after Radiofrequency Ablation for Liver Cancer: Correlation with Hepatic Perfusion Disorders.

Purpose: To quantitatively investigate the correlation between liver fat content and hepatic perfusion disorders (HPD) after radiofrequency ablation (RFA) for liver cancer using magnetic resonance imaging (MRI)-determined proton density fat fraction (PDFF). Materials and methods: A total of 150 liver cancer patients underwent liver MRI examination within one month after RFA and at four months after RFA. According to the liver fat content, they were divided into non-, mild, moderate, and severe fatty liver groups. The liver fat content and hepatic perfusion disorders were determined using PDFF images and dynamic contrast-enhanced MRI images. The relationship between the liver fat content and HPD was investigated. Results: At the first postoperative MRI examination, the proportion of patients in the nonfatty liver group with hyperperfused foci (11.11%) was significantly lower than that in the mild (30.00%), moderate (42.86%), and severe fatty liver (56.67%) groups (p < 0.05), whereas the proportions of patients with hypoperfused foci (6.67%, 7.5%, 5.71%, and 6.67%, respectively) were not significantly different among the four groups (p > 0.05). In the nonfatty liver group, the liver fat content was not correlated with hyperperfusion abnormalities or hypoperfusion abnormalities. By contrast, in the three fatty liver groups, the liver fat content was correlated with hyperperfusion abnormalities but was not correlated with hypoperfusion abnormalities. At the second postoperative MRI examination, six patients in the nonfatty liver group were diagnosed with fatty liver, including two patients with newly developed hyperperfusion abnormalities and one patient whose hypoperfusion abnormality remained the same as it was in the first postoperative MRI examination. Conclusion: There was a high correlation between the liver fat content and hyperperfusion abnormalities after RFA for liver cancer. The higher the liver fat content was, the higher the was risk of hyperperfusion abnormalities. However, there was little correlation between liver fat content and hypoperfusion abnormalities, and the increase in postoperative liver fat content did not induce or alter the presence of hypoperfused foci.

Hepatic Perfusion Disorders Secondary to Superior Vena Cava Obstruction: Two Cases Reports

Hepatic Perfusion Disorders Secondary to Superior Vena Cava Obstruction: Two Cases Reports

Magnetic resonance imaging and diffusion weighted imaging features of focal peliosis hepatis

Objective: To investigate the MRI and diffusion weighted imaging (DWI) features of focal peliosis hepatis. Methods: The clinical data and MRI of 19 cases with focal peliosis hepatis confirmed by pathology from January 2012 to March 2018 in Zhongshan Hospital of Fudan University were retrospectively analyzed. The number, location, size, shape, signal intensity of plain scan of lesions, enhancement pattern of lesions, vessels within lesions, and perfusion disorders of hepatic parenchyma were analyzed. The apparent diffusion coefficient (ADC) values of the lesions and adjacent hepatic parenchyma were measured, then the differences between them were explored statistically. All 24 lesions were categorized into group A with tumor-related chemotherapy and group B without tumor-related chemotherapy. The differences of MR features between the two groups were explored statistically. Results: In all 24 lesions, 22 lesions were located in the right lobe, 2 lesions in the left lobe. The median size was 7.5-72.0 (24.4±17.2) mm.On T(1)WI,21 lesions showed slightly hypointensity, 1 lesion showed slightly hyperintensity and 2 lesions were isointensity; all 24 lesions showed slightly hyperintensity on T(2)WI, and isointensity or slightly hyperintensity on DWI. The mean ADC value was (1.511±0.415)×10(-3) mm(2)/s in the lesions and (1.769±0.690)×10(-3) mm(2)/s in the adjacent hepatic parenchyma, which showed no difference between the two groups (P>0.05). On dynamic MR images, 20 lesions showed gradually filling enhancement, 4 lesions showed markedly and persistent enhancement. Punctiform or filiform vessels were found in 9 lesions. Adjacent hepatic perfusion disorders showed in 8 lesions. The median lesion size was 7.5-38.5(17.6±9.8) mm in the tumor-related-chemotherapy group and 9.0-72.0(33.8±21.2) mm in the no chemotherapy group.There was significant difference between the two groups (P<0.05). Conclusions: The MRI performance of focal peliosis hepatis had a certain characteristic. MRI combined with diffusion weighted imaging could help to make diagnoses.

MRI manifestations of hepatic perfusion disorders.

The present study aimed to analyze the magnetic resonance imaging (MRI) results from patients with hepatic perfusion disorders (HPD) and liver diseases, in order to assess the pathogenetic mechanisms. This was completed byanalyzing the causes of HPD in 35 patients to assess if they were associated with arterioportal shunt, and classify the patients according to results from the MRI scans. Of the 35 patients, 26 (74.3%) with HPD presented with hepatocellular carcinoma, a major cause of HPD. The HPD phenomenon in 35 patients was not identified as obvious abnormal lesions on T2WI and T1WI according to the isointensity on diffusion weighted images. Enhanced scanning showed hyperintense signals on the arterial phase images, isointense or hyperintense signals on portal phase and delayed phase images. According to their MRI findings, hepatic perfusion disorders may be divided into different types, as follows: Diffuse, lobe or segment type, wedge type and platy. The HPD phenomenon may herald an underlying abnormality of liver disease and MRI may accurately diagnose HPDs in liver diseases.

Multi-Slice Computer Tomography Dynamic Enhanced Expression and Clinical Significance of Hepatic Perfusion Abnormalities

&lt;p&gt;&lt;strong&gt;Objective: &lt;/strong&gt;To investigate the imaging features and clinical significance of the dynamic enhanced CT perfusion of the liver. &lt;strong&gt;Method: &lt;/strong&gt;112 cases of hepatic perfusion disorders were collected, including 22 cases of hepatocellular carcinoma with tumor thrombus, 12 cases of bile duct carcinoma, 16 cases of cholangitis, 31 cases of hemangioma, 10 cases of liver cirrhosis and liver laceration injury in 5 cases, 16 cases of liver abscess, all cases were surgically or clinically confirmed. All cases were performed with three phase enhanced scanning, and the images were loaded into the PACS system. &lt;strong&gt;Results&lt;/strong&gt;&lt;strong&gt;: &lt;/strong&gt;In 26 cases, 76 cases with patchy enhancement around the focus were shown in 10 cases with patchy enhancement. Arterial phase was in 47 cases, 12 cases with high perfusion, and 53 cases with high perfusion. &lt;strong&gt;Conclusion: &lt;/strong&gt;Correct understanding of liver perfusion abnormalities in the diagnosis of lesions and reduce the true extent of the lesion is important.&lt;/p&gt;

The enhancement features of hepatocelluar carcinoma using 320-row CT multi-phase dynamic volumetric contrast scan

Objective To investigate the diagnostic value of 320-row CT multi-phase dynamic volumetric contrast scan for hepatocellular carcinoma (HCC).Methods 40 HCC patients were investigated using a 320-row CT multi-phase dynamic volumetric contrast scan (Aquilion One; Toshiba Medical,Otawara,Japan).The time density curves (TDC) of hepatic artery,hepatocelluar carcinoma and liver parenchyma could be delineated on the basis of the initial data.The time to peak enhancement and the total time of duration enhancement of the 40 HCCs were recorded.The enhancement of tumor in the whole arterial phase was analyzed.Results 40 HCCs were detected by the 320-row CT multiphase dynamic volumetric contrast scan.The mean time to peak enhancement of 40 HCCs was 29(22-36)s.The mean time of durative enhancement was 14s.31 hepatic perfusion disorders (HPD) were detected by the 320-row CT multi-phase dynamic volumetric contrast scan,showing dot,patchy,strip and wedge.The mean time to enhancement was 22 s.The mean time of durative enhancement was 12s.The mean time of restoring to isodensity was 34s.Conclusions 320-row CT multi-phase dynamic volumetric contrast scan with a low dose of contrast agent could result in real-time capture of accurate information for the time to peak enhancement and the total time of duration enhancement of tumor,thus overally reflected the feature and mechanism of tumor enhancement,and provided important image information for diagnosis and differential diagnosis of HCC. Key words: Hepatocelluar carcinoma; Dynamic contrast scan, multi-phase

CT of Nonneoplastic Hepatic Vascular and Perfusion Disorders

The unique dual blood supply of the liver (75% portal venous, 25% hepatic arterial) makes multiphase helical computed tomography (CT) a highly suitable technique for hepatic evaluation with imaging in two (arterial and portal venous) or more phases. Multiphase helical CT has become an important tool in the detection and characterization of hepatic tumors. In some situations, hemodynamic changes might mimic neoplastic or inflammatory lesions and evoke diagnostic uncertainty. To confidently identify hepatic conditions such as venous outflow obstruction (Budd-Chiari syndrome), arterioportal shunts, hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome), peliosis hepatis, passive congestion, and hepatic infarction, radiologists must be familiar with the disease-specific CT appearances and related clinical manifestations.

Hepatic perfusion disorders: Etiopathogenesis and related diseases

In this article, we have reviewed the hepatic perfusion disorder (HPD), etiopathogenesis of HPD and corresponding diseases. Review of the literature was based on computer searches (PubMed, Index Medicus) and personal experiences. We considered HPD reflects perfusion differences due to redistribution of arterial blood flow among segments, subsegments and lobes of the liver. The plain CT scan findings of HPD manifests as triangular or wedge-shaped areas of low attenuation. On contrast-enhanced CT scan, HPD manifests multiple (or single) transient wedge-shaped, rotundloid or irregular appearance, homogeneous hyperattenuation (in less cases, hypoattenuation) during the hepatic arterial phase (HAP) and isoattenuated or slightly hyperattenuated areas during the portal arterial phase. Dynamic enhanced magnetic resonance (MR) features are similar to enhanced CT scan. Angiographic findings include non-opacification of portal vein on portograms or wedge-shaped segmental staining in arterial and parenchymal phases on hepatic angiograms. The causes of HPD are arterioportal shunts (APS), intrahepatic vascular compressions and portal vein occlusion, steal phenomenon by hypervascular tumors, vascular variations and any other unknown reasons. It is very important for radiologists to be familiar with the various appearances of HPD to avoid false-positive diagnosis of pseudolesions and not to overestimate the extent of the disease.

Hepatic perfusion disorders: Etiopathogenesis and related diseases

Hepatic perfusion disorders: Etiopathogenesis and related diseases

Hepatic perfusion disorders: Etiopathogenesis and related diseases

Hepatic perfusion disorders: Etiopathogenesis and related diseases

Hepatic Perfusion Disorders: A Pictorial Review of CT and MR Imaging

The liver has a unique dual blood supply through the portal vein and the hepatic artery. There are several communications between these two vessels under various conditions such as in hepatic tumors, trauma and liver cirrhosis, vascular compromise, among others. When vascular compromise occurs, this dual blood supply system can cause changes in the volume of blood flow in individual vessels or even in the direction of blood flow. With rapid image acquisition and increased resolution available in multislice CT and MR imaging, hepatic perfusion disorders are now more frequently encountered than in the past. Familiarity with imaging findings of these perfusion disorders will be helpful in characterizing focal hepatic lesions and will also help to avoid false positive diagnoses.

Hereditary hemorrhagic telangiectasia: multi-detector row helical CT assessment of hepatic involvement.

To describe findings obtained with multi-detector row helical computed tomography (CT) of the liver in patients with hereditary hemorrhagic telangiectasia. Multiphasic multi-detector row helical CT was performed in 70 consecutive patients (29 females and 41 males; mean age, 48.5 years; age range, 15-75 years): 64 considered to have hereditary hemorrhagic telangiectasia and six suspected of having the disease. Scanning delay was achieved by using a test bolus of contrast medium to obtain early arterial phase, late arterial phase, and portal venous phase images. Multiplanar and angiographic reconstructions were then generated. The presence of shunts, hepatic perfusion disorders, telangiectases, other vascular lesions, indirect signs of portal hypertension, and vascular anatomic variants were evaluated by two radiologists in consensus. Fifty-two of 70 (74%) patients had hepatic vascular abnormalities. Only four of 52 (8%) patients were symptomatic. Arterioportal shunts were present in 27 of 52 (52%) patients, arteriosystemic shunts in eight of 52 (15%), and both shunt types in 17 of 52 (33%). In 34 of 52 (65%) patients, parenchymal perfusion disorders were detected. Telangiectases were found in 33 of 52 (63%) patients. Large confluent vascular masses were identified in 13 of 52 (25%) patients. In 31 of 52 (60%) patients, indirect CT signs of portal hypertension were detected, but only one had clinical signs of this condition. Vascular anatomic variants were detected in seven patients (13%). Multi-detector row helical CT and reconstructions depict the complex hepatic vascular alterations typical of hereditary hemorrhagic telangiectasia.

Improved diagnosis of hepatic perfusion disorders: value of hepatic arterial phase imaging during helical CT.

The liver has a unique dual blood supply, which makes helical computed tomography (CT) a highly suitable technique for hepatic imaging. Helical CT allows single breath-hold scanning without motion artifacts. Because of rapid image acquisition, two-phase (hepatic arterial phase and portal venous phase) evaluation of the hepatic parenchyma is possible, improving tumor detection and tumor characterization in a single CT study. The arterial and portal venous supplies to the liver are not independent systems. There are several communications between the vessels, including transsinusoidal, transvasal, and transplexal routes. When vascular compromise occurs, there are often changes in the volume of blood flow in individual vessels and even in the direction of blood flow. These perfusion disorders can be detected with helical CT and are generally seen as an area of high attenuation on hepatic arterial phase images that returns to normal on portal venous phase images; this finding reflects increased arterial blood flow and arterioportal shunting in most cases. Familiarity with the helical CT appearances of these perfusion disorders will result in more accurate diagnosis. By recognizing these perfusion disorders, false-positive diagnosis (hypervascular tumors) or overestimation of the size of liver tumors (eg, hepatocellular carcinoma) can be avoided.

Evaluation of hepatic perfusion disorders with double-phase spiral CT.

Double-phase (dual-phase) spiral computed tomography (CT) represents a technologic advance that allows two evaluations of hepatic blood flow during a single 19-29-second breath hold: once during the hepatic arterial phase (HAP) and again during the portal venous phase (PVP). Perfusion disorders of the hepatic parenchyma are more readily observed at double-phase spiral CT. The various hepatic perfusion disorders are related to (a) portal venous inflow obstruction, (b) hepatic venous outflow obstruction (e.g., Budd-Chiari syndrome, cardiac failure, mediastinal fibrosis), (c) mediastinal or thoracic venous inlet obstruction, (d) focal liver lesions, (e) inflammatory processes, (f) normal anatomic variants in the hepatic blood supply, (g) altered hemodynamics after the placement of a transjugular intrahepatic portosystemic shunt, and (h) uncertain causes. In general, the area of involvement appears hyperattenuating on HAP images and of normal or near-normal attenuation on PVP images. Familiarity with the spiral CT appearances of different types of perfusion disorders allows the radiologist to separate clinically insignificant flow phenomena from perfusion disorders caused by underlying parenchymal or vascular disease.