OBJECTIVE: To correlate the isolated sonographic finding of umbilical cord cyst with fetal anomalies such as chromosomopathies and structural changes. According to the medical literature, the clinical implications of the sonographic finding of umbilical cord cyst in the second and third trimesters of pregnancy are well established; however, the meaning of this finding in the first trimester still remains controversial. MATERIALS AND METHODS: A retrospective study was developed with consecutive, pregnant women with single living fetuses presenting with umbilical cord cyst as an isolated finding, over a 10-year period (1996-2006). Ultrasound studies were performed in all cases for screening of fetal anomalies after the diagnosis of umbilical cord cyst. Neonates and umbilical cords were evaluated after delivery for the presence of abnormalities. RESULTS: Nine cases presenting umbilical cord cyst as a sole finding with no other sonographic marker for fetal abnormality were evaluated. Two cases were detected in the first pregnancy trimester and seven cases in the second and third trimesters. Fetal cytogenetic study was done by means of amniocentesis in two cases. No newborn presented with structural anomalies or aneuploidy. CONCLUSION: Isolated sonographic finding of umbilical cord cyst did not imply increased risk for fetal structural anomalies or aneuploidies.

Keywords: Fetus, Umbilical cord, Cysts, Ultrasonography, Chromosome aberrations

Aneurysms in the splenoportomesenteric system constitute a rare entity whose etiology is still to be determined. Predisponent factors include portal hypertension, chronic hepatic disease and trauma, among others. The authors present a case of an aneurysm at the splenomesenteric confluence where it joins the portal vein, in a female, 62-year-old patient with no predisponent factor.

Keywords: Aneurysm, Portal vein, Splenic vein, Mesenteric veins

OBJECTIVE: To evaluate the inter-observer agreement between Doppler ultrasonography and magnetic resonance imaging in the quantification of portal blood flow in healthy individuals, as well as evaluating the reproducibility of both methods. MATERIALS AND METHODS: A prospective, transverse, observational and self-paired study was developed evaluating 20 healthy volunteers whose portal blood flow was measured by means of Doppler ultrasonography and magnetic resonance imaging performed by two independent observers. Interobserver and intermethod agreements were calculated using the intraclass and Pearson's correlation coefficients. RESULTS: The agreement between Doppler ultrasonography and magnetic resonance imaging was low (intraclass coefficient: 1.9%-18.2%; Pearson's coefficient: 0.1%-13.7%; p=0.565). Mean values for the portal blood flow measured by Doppler ultrasonography and magnetic resonance imaging were respectively 0.768 l/min and 0.742 l/min. Interobserver agreement for quantification of the portal blood flow by Doppler ultrasonography and magnetic resonance imaging was respectively reasonable (intraclass coefficient: 43.3%; Pearson's coefficient: 43.0%) and excellent (intraclass coefficient: 91.4%; Pearson's coefficient: 93.4%). CONCLUSION: In the present study, magnetic resonance imaging demonstrated to be a reliable method for quantifying the portal blood flow, with a higher interobserver agreement than Doppler ultrasonography. The intermethod agreement was low.

Keywords: Portal blood flow, Magnetic resonance imaging, Ultrasonography

OBJECTIVE: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. MATERIALS AND METHODOS: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. RESULTS: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). CONCLUSION: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement.

Keywords: Portal flow, Measurement, Doppler ultrasonography, Reproducibility, Portal hypertension

OBJECTIVE: The aim of the present study was to analyze splenic impedance indices - resistive index (RI) and pulsatility index (PI) - in patients with chronic liver disease. MATERIALS AND METHODS: Forty-two patients with hepatic cirrhosis and 21 patients with chronic hepatitis were prospectively evaluated. RESULTS: In patients with cirrhosis, both indices were higher (RI = 0.63 ± 0.08; PI = 1.02 ± 0.22) than those found in patients with chronic hepatitis (RI = 0.58 ± 0.06; PI = 0.89 ± 0.15) and in the control group individuals (RI = 0.57 ± 0.04; PI = 0.87 ± 0.11). However, cirrhotic patients with evidence of collateral circulation at ultrasound presented lower resistive indices (RI = 0.60 ± 0.08) compared with those without collateral circulation (RI = 0.65 ± 0.07), possibly due to the portosystemic shunt caused by collateral vessels. There was no significant difference of indices between patients with and without esophageal varices. CONCLUSION: The present study has demonstrated that splenic artery impedance indices may be useful in the evaluation of patients affected by chronic liver disease and portal hypertension, contributing with additional data at color Doppler ultrasound.

Keywords: Impedance indices, Splenic artery, Portal hypertension, Radiology

Portal vein thrombosis may be associated with many alterations, such as the presence of tumors (for example, hepatocellular carcinoma, metastatic liver disease and carcinoma of the pancreas) as well as pancreatitis, hepatitis, septicemia, trauma, splenectomy, portacaval shunts, hypercoagulable conditions (for example, pregnancy), in neonates (for example, omphalitis and umbilical vein catheterization) and in acute dehydration. The authors discuss herein the sonographic features of portal vein thrombosis as well as some aspects of clinical relevance.

Keywords: Portal vein, Portal vein thrombosis, Ultrasound

OBJECTIVE: A marked impact on the splanchnic circulation is seen in liver cirrhosis. Doppler ultrasonography (DUS) was performed in a group of patients with end-stage liver cirrhosis before, during and after orthotopic liver transplantation (OLT) in order to investigate the hemodynamic changes in portal vein flow velocity. MATERIALS AND METHODS: Fifty-four patients submitted to OLT and intraoperative DUS were prospectively studied from January 2002 to July 2003. Seventeen patients were excluded because of missing data due to either technical difficulties to obtain the measurements or early patient death. All 37 patients included in the analysis had liver cirrhosis mainly associated with hepatitis C virus infection and alcoholic disease. Patients were submitted to DUS just before OLT, intraoperatively after graft reperfusion, and in the postoperative period (1st and 7th postoperative days). Mean flow velocity was measured at main, right and left portal veins. Statistical analysis was performed using paired t test. Differences were significant when p < 0.05. RESULTS: The mean pre-OLT velocity in the portal vein was 16.0 cm/s. Intraoperative measurements obtained few minutes after graft reperfusion showed an increase in portal vein velocity to 84.09 cm/s. Portal flow velocity was 71.0 cm/s and 58.5 cm/s in the 1st and 7th postoperative days, respectively. Intraoperative and postoperative mean flow velocity in the portal vein was significantly higher than in pre-OLT period (p < 0.001). On the 7th postoperative day, the mean flow velocity in the portal vein decreased significantly compared to intraoperative values (p < 0.05). CONCLUSION: In liver transplantation, there is a significantly increase in mean flow velocity in the portal vein immediately after graft reperfusion when compared to pre-OLT data. Likewise, after this initial peak flow there is a significant and progressive decrease in mean flow velocity in the portal vein, which tends to normalize on the 7th postoperative day.

Keywords: Portal vein, Mean velocity, Transplantation, Hemodynamics

Ultrasonography and Doppler ultrasonography have dramatically improved the diagnosis of portal hypertension thanks to the noninvasive visualization of the liver, spleen and splanchnic blood flow. In this article the authors discuss some important issues raised by the use of ultrasound and Doppler in the evaluation of portal hypertension.

Keywords: Portal hypertension, Liver, Ultrasound, Doppler

Transjugular intrahepatic portosystemic shunts (TIPS) are the most recent and popular technique for the relief of symptomatic portal hypertension, particularly in patients with varices and gastrointestinal bleeding and less often in patients with refractory ascites. TIPS may be complicated by stenosis or occlusion of the stent. Sonography with Doppler provides a noninvasive method for monitoring patients with TIPS. The authors report the recent sonographic and Doppler findings in patients with normal functioning TIPS and patients with stenosis or occlusion of TIPS.

Keywords: Liver, Portal hypertension, Cirrhosis, Liver transplantation, Transjugular intrahepatic portosystemic shunt

OBJECTIVE: To develop a nomogram for the umbilical cord cross-sectional area (UCCSA) in normal pregnancies in women between 20 to 40 weeks gestation. MATERIALS AND METHODS: A cross-sectional study was developed to determine reference ranges for the UCCSA during normal pregnancies (patients with known dates of last menstrual period, and a normal ultrasound examination before the 20th week of gestation). The measurements of the UCCSA were obtained using a plane adjacent to the insertion of the cord in the abdomen. A 3.5 MHz transabdominal transducer was used on all ultrasound equipment utilized (a Synergy Multi Sync M500, a Toshiba 140 and a Toshiba Corevision). The statistical analysis was performed using the SPSS (Statistical Package for Social Sciences) software. RESULTS: The Kolmogorov-Smirnov test showed a normal distribution of the data and the nomogram was constructed by linear regression. The analysis of variance (F test = 356.27) showed that our model was significant at a p < 0.01 level, and therefore represented adequately the studied population. The confidence interval (95%) contained the real value of the UCCSA. The equation constructed for the UCCSA (y) according to the gestational age (x) was: y = -532.27 + 44.358x - 0,655x². CONCLUSION: The nomogram developed for the UCCSA shows a progressive increase of the UCCSA up to the 32nd week, stabilization until the 34th week, and decrease after the 35th week of gestation.

Keywords: Umbilical cord, Cross-sectional area, Fetal growth

Objective: To evaluate the agreement between Doppler ultrasonography and magnetic resonance imaging as well as the interobserver reproducibility of both methods in the measurement of portal blood flow in schistosomal patients. Materials and methods: A cross-sectional, observational, self-paired study evaluated 21 patients with schistosomiasis mansoni submitted to measurement of portal blood flow with phase-contrast magnetic resonance imaging and Doppler ultrasonography. Results: A poor intermethod agreement was observed (intraclass correlation coefficient: 34.5% [CI 95%]). On the other hand, the interobserver reproducibility was excellent in the evaluation by magnetic resonance imaging (intraclass correlation coefficient: 99.2% [CI 95%] / Pearson’s correlation coefficient: 99.2% / portal blood flow = 0.806) and by Doppler ultrasonography (intraclass correlation coefficient: 80.6 to 93.0% [CI 95%] / Pearson’s correlation coefficient: 81.6% to 92.7% / portal blood flow = 0.954, 0.758 and 0.749). Conclusion: There is a poor intermethod agreement in the measurement of portal blood flow. Nevertheless, contrastphase magnetic resonance imaging and Doppler ultrasonography demonstrated to be reproducible methods presenting excellent interobserver agreement in the quantification of portal blood flow in patients with hepatosplenic schistosomiasis-related portal hypertension.

Keywords: Portal blood flow; Magnetic resonance imaging; Doppler ultrasonography; Reproducibility; Portal hypertension.

The present report describes the case of a child that after blunt abdominal trauma presented with portal thrombosis followed by progressive splenomegaly and jaundice. Ultrasonography and percutaneous cholangiography revealed biliary dilatation secondary to choledochal stenosis caused by dilated peribiliary veins, characterizing a case of portal biliopathy. The present case report is aimed at presenting an uncommon cause of this condition.

Keywords: Portal cholangiopathy; Portal biliopathy; Portal hypertension; Portal vein cavernous transformation.

The authors report a case of umbilical venous catheter malposition with air in the portal venous system in a preterm neonate. Initially, the hypothesis of necrotizing enterocolitis was considered, but the newborn progressed with no finding of disease and the air disappeared at follow-up radiography. The differential diagnosis of such a finding can avoid unnecessary clinical treatments.

Keywords: Umbilical venous catheter; Newborn; Portal air; Necrotizing enterocolitis; Radiological study.

Portosystemic shunts are enlarged vessels that form collateral pathological pathways between the splanchnic circulation and the systemic circulation. Although their causes are multifactorial, portosystemic shunts all have one mechanism in common—increased portal venous pressure, which diverts the blood flow from the gastrointestinal tract to the systemic circulation. Congenital and acquired collateral pathways have both been described in the literature. The aim of this pictorial essay was to discuss the distinct anatomic and imaging features of portosystemic shunts, as well as to provide a robust method of differentiating between acquired portosystemic shunts and similar pathologies, through the use of illustrations and schematic drawings. Imaging of portosystemic shunts provides subclinical markers of increased portal venous pressure. Therefore, radiologists play a crucial role in the identification of portosystemic shunts. Early detection of portosystemic shunts can allow ample time to perform endovascular shunt operations, which can relieve portal hypertension and prevent acute or chronic complications in at-risk patient populations.

Keywords: Collateral circulation; Splanchnic circulation; Hypertension, portal/complications.

Portal vein thrombosis refers to complete or partial obstruction of the portal venous system, in the intrahepatic or extrahepatic venous tract or even in the splenic or superior mesenteric veins. This common and potentially fatal condition can develop in various clinical contexts, especially those of liver cirrhosis, hepatocellular carcinoma, and other solid tumors. Certain characteristics, such as the time since the onset of the thrombus (acute or chronic), its biology (hematic or tumoral), the presence of collateral vessels, and the magnetic resonance imaging aspects, are important components of a thorough, careful analysis, as well as informing decisions regarding the appropriate therapeutic strategy. Here, we present a brief review of the anatomy of the portal venous system and a systematic approach to analyzing the condition, using a mnemonic (ABCD, for age, biology, collaterals, and diffusion). We discuss the various imaging methods and illustrate our discussion with images selected from the case files archived at our facility.

Keywords: Portal vein; Venous thrombosis; Hypertension, portal; Collateral circulation; Magnetic resonance imaging.