Portal Shunt Research Articles

The recipient celiac trunk as an alternative to the native hepatic artery for arterial reconstruction in adult liver transplantation.

During liver transplantation (LT), the recipient hepatic artery (RHA) cannot always be used, and alternatives include aortohepatic conduits and the splenic artery (SA). We report our experience with arterial reconstruction on the recipient celiac trunk (RCT), which has rarely been described. Since January 2013, we have been using the RCT when the RHA could not be used. All cases were discussed in a multidisciplinary LT meeting, and arterial patency or anomalies were systemically viewed with computed tomography (CT) scan. The RCT was used after section-ligation of all celiac trunk collaterals. Until May 2014, the RHA could not be used in 11/139 (8%) patients who underwent LT. Postoperative arterial patency was assessed by serial Doppler ultrasound and CT scan. The advantages and disadvantages of the different arterial conduits were evaluated. The RCT was used in 7/11 (64%) patients. Mean follow-up was 10 (6-15) months. The patency rate was 100%, and 1 patient with associated portal shunting died at day 20 from septic complications. No related gastric or splenic complications were encountered. The RCT could not be used in 4 patients with reconstruction on the SA (n = 2), infrarenal (n = 1), and supraceliac aorta (n = 1). The patency rate was 75%. One patient with SA conduit and portal shunting developed pancreatitis/anastomotic pseudoaneurysm with secondary rupture. An emergency infrarenal conduit was created, which was later embolized because of infected pseudoaneurysms. Although the literature reports a higher risk of thrombosis with aortohepatic conduits, no long-term results are available for the SA conduits, and only 1 report is available for the RCT. In conclusion, this study shows that the RCT is a good alternative to the RHA and can be used in two-thirds of patients with inadequate RHA flow.

Histological Spectrum of Idiopathic Noncirrhotic Portal Hypertension in Liver Biopsies From Dialysis Patients.

Liver biopsy is performed for various indications in dialysis patients. Being a less-common subset, the hepatic pathology in renal dialysis is not well documented. Idiopathic noncirrhotic portal hypertension (INCPH) is a clinical entity associated with unexplained portal hypertension and/or a spectrum of histopathological vascular changes in the liver. After encountering INCPH and vascular changes of INCPH in 2 renal dialysis patients, we sought to further investigate this noteworthy association. A random search for patients on hemodialysis or peritoneal dialysis with liver biopsy was performed. Hematoxylin and eosin, reticulin, trichrome, and CK7 stains were performed on formalin-fixed, paraffin-embedded tissue sections. Histopathological features were reviewed, and the results were correlated with clinical findings. In all, 13 liver biopsies were retrieved. The mean cumulative duration of dialysis was 50 months (range = 17 months to 11 years). All patients had multiple comorbidities. Indications for biopsy were a combination of abnormal liver function tests (6), portal hypertension (4), ascites (3), and possible cirrhosis (3). Two patients with portal hypertension underwent multiple liver biopsies for diagnostic purposes. All (100%) biopsies showed some histological features of INCPH, including narrowed portal venous lumen (9), increased portal vascular channels (8), shunt vessels (3), dilated sinusoids (9), regenerative nodule (5), and features of venous outflow obstruction (3). No cirrhosis was identified. Liver biopsies from patients on dialysis demonstrate histopathological vascular changes of INCPH. Some (31%) patients present with portal hypertension without cirrhosis. The histological changes may be reflective of underlying risk factors for INCPH in this group.

C-Arm Cone-Beam Volume CT in Transjugular Intrahepatic Portosystemic Shunt: Initial Clinical Experience.

The purpose of this study was to compare two-dimensional digital subtraction angiography (2D-DSA) with C-arm cone-beam volume computed tomography (CACT) in the evaluation of portal vein entry and shunt course during transjugular intrahepatic portosystemic shunt (TIPS) procedure. Between May 2010 and November 2011, 21 patients who underwent direct portography in anteroposterior and lateral projections and subsequent CACT before stent placement during TIPS creation were reviewed retrospectively. CACT images were examined for evaluation of the portal vein entry and shunt course in comparison to 2D-DSA images by two experienced interventional radiologists. CACT was proven to be better than 2D-DSA in identification of the portal vein entry (P < 0.001) and intra- or extrahepatic puncture (P < 0.001). No significant difference was observed in evaluating the shunt course (P = 0.086). The portal vein entry was considered inappropriate in seven (33%) out of 21 patients; among them, four cases were due to extrahepatic puncture, and three cases were due to peripheral puncture of the portal vein which may result in stent kinking. While 2D-DSA remains the standard imaging method to evaluate portal vein entry, shunt course, and portal vein anatomy during TIPS procedure, CACT can effectively identify the portal vein entry and assess shunt course in difficult cases intra-procedurally, hence may reduce the risk of potential life-threatening intra-abdominal hemorrhage and shunt dysfunction.

Spleen-preserving proximal splenic-left intrahepatic portal shunt for the treatment of extrahepatic portal hypertension in children

PurposeThe Rex shunt has been employed successfully to treat patients with extrahepatic portal hypertension. In the conventional Rex shunt, the internal jugular vein is used as a venous graft. Inevitably, such a procedure requires neck exploration and sacrifice of the internal jugular vein. The authors describe a novel adaptation of spleen-preserving spleno-Rex bypass, successfully carried out in children with extrahepatic portal hypertension. MethodsThe mean age of the four patients (1 boy, 3 girls) was 46months at the time of operation. All children had a history of upper gastrointestinal bleeding, and suffered from splenomegaly and hypersplenism. Spleen-preserving proximal splenic-left intrahepatic portal shunt was performed in all patients. The splenic artery and vein were ligated at the splenic hilum, and the splenic vein was completely separated from the bed of the pancreas to its junction with the inferior mesenteric vein. The freed splenic vein was anastomosed to left portal vein. The short gastric and left gastroepiploic vessels were kept intact to supply and drain the spleen. All patients were followed-up for 7–33months (median: 21.5months). ResultsThe spleen-preserving spleno-Rex bypass was successfully performed in all 4 patients. The median operative time was 225min (range: 215–260min). One patient received blood transfusion, and the postoperative length of hospital stay varied from 4 to 6days (median: 4.5days). Intraoperative portal venous angiography demonstrated the patency of the shunt in all patients. Postoperatively, the complete blood count normalized and the biochemistry tests were within normal range. Postoperative ultrasound confirmed shunt patency and satisfactory flow in the proximal splenic-portal shunt in each patient. The size of the spleen decreased and there was no recurrence of variceal bleeding. ConclusionsThe spleen-preserving spleno-Rex bypass is a viable option to treat EHPVO in children.

4:33 PM Abstract No. 213 - Portal vein recanalization-transjugular intrahepatic portosystemic shunt using the trans-splenic approach to achieve transplant candidacy in patients with chronic portal vein thrombosis: proof of concept

PurposeThe aim of this study is to test our hypothesis that the trans-splenic (TS) route can be employed as an alternate approach for portal vein recanalization-transjugular portosystemic shunts (PVR-TIPS) for chronic main portal vein thrombosis (mPVT) in potential transplant candidates.Materials and MethodsWith IRB approval, 11 consecutive patients with cirrhosis-induced chronic mPVT underwent trans-splenic PVR-TIPS in 2013-2014. All patients were denied listing by our transplant team due to the presence of mPVT, a relative contraindication at our center. Patients were followed for adverse events. PV patency at follow-up was assessed by 1-month splenoportography and subsequently by ultrasound/MRI every 3 months. Following PVR-TIPS, patients were reviewed (and subsequently listed) at weekly multidisciplinary conference.ResultsPVR-TIPS using the TS approach was successful in all 11 patients with no major complications. Median age was 61 years (range: 33-67), 9/11 (82%) were male, and non-alcoholic steatohepatitis / hepatitis C were the leading causes of liver disease (8/11, 4 each). Complete mPVT was found in 8/11 (73%) patients. Four out of 11 patients (36%) had a MELD >18 and 8/11 (73%) had a baseline Child-Pugh score 7-10. Minor adverse events occurred in 2/11 (fever, encephalopathy). Five out of eleven patients (45%) exhibited some minor remaining thrombus in the PV at the end of the procedure; of these patients, 3/5 had complete thrombus resolution at one month, with the remaining 2/5 resolving at 3 months (no anticoagulation). Three patients underwent successful transplantation with end-to-end anastomoses.ConclusionTrans-splenic PVR-TIPS is a potentially safe and effective method to treat PVT and improve transplant candidacy. PurposeThe aim of this study is to test our hypothesis that the trans-splenic (TS) route can be employed as an alternate approach for portal vein recanalization-transjugular portosystemic shunts (PVR-TIPS) for chronic main portal vein thrombosis (mPVT) in potential transplant candidates. The aim of this study is to test our hypothesis that the trans-splenic (TS) route can be employed as an alternate approach for portal vein recanalization-transjugular portosystemic shunts (PVR-TIPS) for chronic main portal vein thrombosis (mPVT) in potential transplant candidates. Materials and MethodsWith IRB approval, 11 consecutive patients with cirrhosis-induced chronic mPVT underwent trans-splenic PVR-TIPS in 2013-2014. All patients were denied listing by our transplant team due to the presence of mPVT, a relative contraindication at our center. Patients were followed for adverse events. PV patency at follow-up was assessed by 1-month splenoportography and subsequently by ultrasound/MRI every 3 months. Following PVR-TIPS, patients were reviewed (and subsequently listed) at weekly multidisciplinary conference. With IRB approval, 11 consecutive patients with cirrhosis-induced chronic mPVT underwent trans-splenic PVR-TIPS in 2013-2014. All patients were denied listing by our transplant team due to the presence of mPVT, a relative contraindication at our center. Patients were followed for adverse events. PV patency at follow-up was assessed by 1-month splenoportography and subsequently by ultrasound/MRI every 3 months. Following PVR-TIPS, patients were reviewed (and subsequently listed) at weekly multidisciplinary conference. ResultsPVR-TIPS using the TS approach was successful in all 11 patients with no major complications. Median age was 61 years (range: 33-67), 9/11 (82%) were male, and non-alcoholic steatohepatitis / hepatitis C were the leading causes of liver disease (8/11, 4 each). Complete mPVT was found in 8/11 (73%) patients. Four out of 11 patients (36%) had a MELD >18 and 8/11 (73%) had a baseline Child-Pugh score 7-10. Minor adverse events occurred in 2/11 (fever, encephalopathy). Five out of eleven patients (45%) exhibited some minor remaining thrombus in the PV at the end of the procedure; of these patients, 3/5 had complete thrombus resolution at one month, with the remaining 2/5 resolving at 3 months (no anticoagulation). Three patients underwent successful transplantation with end-to-end anastomoses. PVR-TIPS using the TS approach was successful in all 11 patients with no major complications. Median age was 61 years (range: 33-67), 9/11 (82%) were male, and non-alcoholic steatohepatitis / hepatitis C were the leading causes of liver disease (8/11, 4 each). Complete mPVT was found in 8/11 (73%) patients. Four out of 11 patients (36%) had a MELD >18 and 8/11 (73%) had a baseline Child-Pugh score 7-10. Minor adverse events occurred in 2/11 (fever, encephalopathy). Five out of eleven patients (45%) exhibited some minor remaining thrombus in the PV at the end of the procedure; of these patients, 3/5 had complete thrombus resolution at one month, with the remaining 2/5 resolving at 3 months (no anticoagulation). Three patients underwent successful transplantation with end-to-end anastomoses. ConclusionTrans-splenic PVR-TIPS is a potentially safe and effective method to treat PVT and improve transplant candidacy. Trans-splenic PVR-TIPS is a potentially safe and effective method to treat PVT and improve transplant candidacy.

Cognitive dysfunction and hepatitis C virus infection

Cognitive dysfunction in patients with chronic hepatitis C virus (HCV) infection is a distinct form of minimal hepatic encephalopathy (MHE). In fact, the majority of HCV-positive patients, irrespective of the grading of liver fibrosis, display alterations of verbal learning, attention, executive function, and memory when they are evaluated by suitable neuropsychological tests. Similarities between the cognitive dysfunction of HCV patients and MHE of patients with different etiologies are unclear. It is also unknown how the metabolic alterations of advanced liver diseases interact with the HCV-induced cognitive dysfunction, and whether these alterations are reversed by antiviral therapies. HCV replication in the brain may play a role in the pathogenesis of neuroinflammation. HCV-related brain dysfunction may be associated with white matter neuronal loss, alterations of association tracts and perfusion. It is unclear to what extent, in patients with cirrhosis, HCV triggers an irreversible neurodegenerative brain damage. New insights on this issue will be provided by longitudinal studies using the protocols established by the diagnostic and statistical manual of mental disorders fifth edition for cognitive disorders. The domains to be evaluated are complex attention; executive functions; learning and memory; perceptual motor functions; social cognition. These evaluations should be associated with fluorodeoxyglucose positron emission tomography and magnetic resonance imaging (MRI) protocols for major cognitive disorders including magnetic resonance spectroscopy, diffusion tensor imaging, magnetic resonance perfusion, and functional MRI. Also, the characteristics of portal hypertension, including the extent of liver blood flow and the type of portal shunts, should be evaluated.

Abstract No. 446 - Lung cryoablation offers procedure flexibility

Abstract No. 446 - Lung cryoablation offers procedure flexibility

Role of per-rectal portal scintigraphy in long-term follow-up of congenital portosystemic shunt

Congenital portosystemic shunt (CPSS) has the potential to cause hepatic encephalopathy and thus needs long-term follow-up, but an effective follow-up method has not yet been established. We aimed to evaluate the importance of per-rectal portal scintigraphy (PRPS) for long-term follow-up of CPSS. We retrospectively examined shunt severity time course in patients (median: 9.6 y, range: 5.2-16.6 y) with intrahepatic (n = 3) or extrahepatic (n = 3) CPSS by using blood tests, ultrasonography or computed tomography, and PRPS. Per-rectal portal shunt index (cutoff: 10%) was calculated by PRPS. PRPS demonstrated that the initial shunt index was reduced in all intrahepatic cases (from 39.7 ± 9.8% (mean ± SD) to 14.6 ± 4.7%) and all extrahepatic cases (from 46.2 ± 10.9 to 27.5 ± 12.6%) during the follow-up period. However, ultrasonography and computed tomography disclosed different shunt diameter time courses between intrahepatic and extrahepatic CPSSs. Initial shunt diameter (5.8 ± 3.5 mm) reduced to 2.0 ± 0.3 mm in intrahepatic cases, but the initial diameter (6.3 ± 0.7 mm) increased to 10.6 ± 1.0 mm in extrahepatic cases. All patients had elevated serum total bile acid or ammonia levels at initial screening, but these blood parameters were insufficient to assess shunt severity because the values fluctuate. PRPS can track changes in the shunt severity of CPSS and is more reliable than ultrasonography and computed tomography in patients with extrahepatic CPSS.

Functional distal splenorenal shunt and splenic artery ligation as portal flow modulation in left lobe living donor transplantation

Functional distal splenorenal shunt and splenic artery ligation as portal flow modulation in left lobe living donor transplantation

Non-cirrhotic Portal Hypertension from Chemotherapy-induced Intrahepatic Non-tumorous Arterioportal Fistula

Purpose: Intrahepatic arterioportal fistulas (APF) are rare, are mostly caused by trauma or malignancy, and can cause presinusoidal portal hypertension. We report a case of chemotherapy-induced non-tumoral intrahepatic APF (CI-APF) presenting with non-cirrhotic portal hypertension (NCPH). A 57-year-old white man presented with chronic abdominal pain and abnormal liver tests for one year (3/13). He underwent right hemicolectomy for cecal adenocarcinoma (2/12), and received adjuvant chemotherapy with FOLFOX (4/12-9/12). His laboratory data showed thrombocytopenia and fluctuating liver tests (AST 43-90 U/L; ALT 49-91U/L; alkaline phosphatase 173-280U/L, and total bilirubin 0.4-1.7mg/dL). Viral and autoimmune hepatitis were excluded. Physical exam was normal. Upper endoscopy showed new trace esophageal varices. Abdominal magnetic resonance imaging reported a large APF in both lobes of the liver, with hyperarterial vascularity perfusing the right hepatic lobe, early shunting to the portal vein, moderate atrophy of right lobe of the liver, distension of the portal vein, and splenomegaly with otherwise patent hepatic vasculature (A). Trans-jugular liver biopsy with wedge pressure and hepatic arteriography showed hepatic vein pressure gradient of 3 mmHg and hepatic arterial to portal vein shunting (B). Liver biopsy was notable for focal sinusoidal dilatation, unremarkable bile ducts, portal tracts, and hepatocytes, with no fibrosis. Prior imaging showed normal hepatic anatomy (2/2012, 6/2012) and fatty infiltration of the liver without vascular abnormalities (11/2012). The occurrence of APF with presinusoidal portal hypertension and the temporal relationship with chemotherapy led to the final diagnosis of NCPH from CI-APF. Several cases of NCPH in patients undergoing chemotherapy for metastatic colorectal cancer have been reported. It is believed that severe hepatic injury from chemotherapy results in benign transformation of the hepatic parenchyma into nodular regenerative hyperplasia (NRH). In our case, the presence of pre-sinusoidal portal hypertension is more supportive of obliterative portal venopathy leading to APF, rather than NRH. Shunt reduction with minimally invasive techniques such as transcatheter hepatic artery embolization have been successfully performed without severe complications.Figure

Treatment with portal vein-hepatic artery shunt for liver cirrhosis and portal hypertension in pigs

Objective To observe the therapeutic effects of end-to-side and side-to-side portal vein-hepatic artery shunts (P-H shunt) in pigs with liver cirrhosis and portal hypertension.Methods There were 15 pigs in each group (control and experimental),and the P-H shunt was made in each animal to observe the process of blood flow into the liver and the reduction of portal vein blood pressure.Results The portal vein pressures before the P-H shunt of pigs in the control and experimental group were (20.51±0.74) cm H2O (1 cm H2O=0.098 kPa) and (30.82±2.53) cm H2O respectively (P＜0.05).Portal vein pressures 30 days after the P-H shunt were(19.75±0.84) cm H2O and (20.84± 1.36) cm H2 O respectively (P＞0.05).The portal vein pressure differences of pigs in the control and experimental group before P-H shunt were (7.20±0.34) cm H2O and (17.34±0.62) cm H2O respectively (P＜0.05).Pressures differences 30 days after the P-H shunt were (6.40±0.21) cm H2O and (7.84 ± 1.32) cm H2O respectively (P＜0.05).Splenic vein injection of methylene blue after the P-H shunt operation stained the liver well.No necrosis and hepatic encephalopathy occurred for 30 days after the P-H shunt,and the splenomegaly gradually returned to normal.Liver function was most affected after the operation and other biochemical markers were least affected.Conclusions The P-H shunt changed the channel of blood flow into the liver,the portal hemodynamic was not affected,and a new balanced mechanism was established to maintain the portal hemodynamic stability.However,further treatment was needed for liver function recovery. Key words: Cirrhosis; Portal hypertension; Animal models; Portal vein-hepatic artery shunt

Portal Shunt Scintigraphy (PSS) in the Evaluation of Patients Suspected of Hereditary Hemorrhagic Telangiectasia

Vascular malformations of the liver in hereditary hemorrhagic telangiectasia may develop high output cardiac failure. Currently, the treatment for refractory hepatic vascular shunts includes hepatic artery embolization. However, hepatic or biliary necrosis may occur if inadequate portal blood flow supplies the liver. In this study, we applied noninvasive portal shunt scintigraphy to determine the portal shunt index for their evaluation. We present a case of the patient with a high PSI value and another case with a normal PSI value (<10%).

Percutaneous transvenous embolization for portosystemic shunts associated with encephalopathy: Long‐term outcomes in 14 patients

To evaluate the clinical outcomes of percutaneous transvenous embolization (PTE) for portosystemic shunt (PSS) associated with encephalopathy Fourteen patients with portosystemic encephalopathy (PSE) were enrolled in this retrospective cohort study. We evaluated technical success, clinical success, complication and outcomes. In cases in which PSS was one of main causes of PSE, three also had splenorenal shunts, four gastrorenal shunts, four superior mesenteric vein systemic shunts, one inferior mesenteric vein systemic shunt and two main trunk of portal vein inferior vena cava shunts. We used only ethanolamine oleate (EO) in five; EO and coils in five; EO, coils and n-butyl 2-cyanoacrylate (NBCA) in two; and coils and NBCA in two patients as embolic materials. The rate of primary and secondary technical success was 93% (13/14 patients) and 100%, respectively. No major complications were encountered related to PTE. Follow-up period was a median of 27 months (range, 12-79). All patients had sustained disappearance of PSE. PSE recurred in one patient because of another PSS development. Thus, clinical success was achieved in 93% (13/14 patients). The ammonia levels 1 year after PTE were significantly improved compared with pre-PTE (median, 102 vs 41 μmol/L) and maintained lower levels 2 and 3 years later. Child-Pugh scores did not change significantly. Esophageal varices were aggravated in 29% (4/14 patients). Five patients died, but no death of hepatic failure related to PTE was encountered. PTE could be one of the useful treatment options for PSE.

Excessive Hepatic Arterial-portal Venous Shunting May Predict Failure of Microparticle Localization in Hepatocellular Carcinomas

Locoregional treatment of hepatocellular carcinomas using yttrium-90 (Y-90) microspheres is an emerging modality, and involves the administration of such radioactive particles directly into the hepatic arterial vasculature. We present the case of a 58-year-old gentleman undergoing evaluation for Y-90 microsphere therapy for hepatocellular carcinoma, in which our findings suggest that significant hepatic arterial portal venous shunting detected during the angiogram maybe a predictor of poor localization of microspheres in the turmor, and that centers that utilize body surface area (BSA) approaches for dosimetry should take note of such findings.

Benign Hepatocellular Tumors: A Multidisciplinary Approach

Benign Hepatocellular Tumors: A Multidisciplinary Approach

The diameter of the originating vein determines esophageal and gastric fundic varices in portal hypertension secondary to posthepatitic cirrhosis

OBJECTIVE:The aim of this study was to determine whether and how the diameter of the vein that gives rise to the inflowing vein of the esophageal and gastric fundic varices secondary to posthepatitic cirrhosis, as measured with multidetector-row computed tomography, could predict the varices and their patterns.METHODS:A total of 106 patients with posthepatitic cirrhosis underwent multidetector-row computed tomography. Patients with and without esophageal and gastric fundic varices were enrolled in Group 1 and Group 2, respectively. Group 1 was composed of Subgroup A, consisting of patients with varices, and Subgroup B consisted of patients with varices in combination with portal vein-inferior vena cava shunts. The diameters of the originating veins of veins entering the varices were reviewed and statistically analyzed.RESULTS:The originating veins were the portal vein in 8% (6/75) of patients, the splenic vein in 65.3% (49/75) of patients, and both the portal and splenic veins in 26.7% (20/75) of patients. The splenic vein diameter in Group 1 was larger than that in Group 2, whereas no differences in portal vein diameters were found between groups. In Group 1, the splenic vein diameter in Subgroup A was larger than that in Subgroup B. A cut-off splenic vein diameter of 8.5 mm achieved a sensitivity of 83.3% and specificity of 58.1% for predicting the varices. For discrimination of the varices in combination with and without portal vein-inferior vena cava shunts, a cut-off diameter of 9.5 mm achieved a sensitivity of 66.7% and specificity of 60.0%.CONCLUSION:The diameter of the splenic vein can be used to predict esophageal and gastric fundic varices and their patterns.

Surgical approach to multifocal hepatocellular carcinoma with portal vein thrombosis and arterioportal shunt leading to portal hypertension and bleeding: a case report

It is reported the case of a 69 years man who presented to the Emergency Room because of pain and abdominal distension from ascites. After admission and paracentesis placement, he developed a digestive hemorrhage due to oesophageal varices from portal ipertension secondary to the formation of a portal shunt concomitant with a multifocal HepatoCellular Carcinoma (HCC) with portal vein thrombosis (PVT). The patient underwent endoscopic varices ligation, twice transarterial embolization (TAE) of arterial branches feeding the shunt and subsequent left hepatectomy. During the postoperative course he developed mild and transient signs of liver failure and was discharged in postoperative day 16. He is alive and disease free 8 months after surgery.

The importance of scatter correction for the assessment of lung shunting prior to yttrium-90 radioembolization therapy

Treatment of inoperable hepatocellular carcinoma or secondary metastases by radioembolization using yttrium-90 (90Y) microspheres is a promising method for the treatment of unresectable liver metastases. A pretreatment scintigraphy planar scan using 99mTc-labelled macroaggregated albumin (99mTc-MAA) injected directly into the hepatic artery is carried out to assess the degree of portal shunting of blood between the liver and the lungs. The quantitative results of this scan are used to modulate the activity of therapeutic 90Y microspheres injected into the patient to limit the radiation dose received by the lungs. The presence of scattered events in the MAA lung shunt scan leads to an overestimation of the true shunting ratio, which in turn leads to the administered therapeutic activity being lowered unnecessarily to comply with the protocols of radiation protection. Overall, this may impact the efficacy of treatment. This study analyses the impact of a window-based analytical scatter-correction method on lung shunt analysis using an anthropomorphic torso phantom, and retrospectively analysed three patient case studies. Our results of scatter in the phantom show a marked decrease in the lung shunt percentage. Clinical analysis of patient data shows that the lung shunt percentage can be overestimated by up to 50% in clinical cases, and depending on the lung shunt percentage, the efficacy of treatment by therapeutic dose reduction may be compromised. Our results indicate that scatter correction should be used on 90Y pretreatment 99mTc-MAA scans in order to more accurately assess the lung shunting percentage before therapy.

Treatment of extrahepatic portal hypertension following a whipple procedure with a rex shunt: Report of a case

The Rex shunt is a mesenteric vein to left portal vein decompressive shunt used for the treatment of portal vein thrombosis and portal hypertension. Its use has been reported primarily in the pediatric population where portal vein thrombosis occurs with some frequency. The shunt is thought to represent a more physiologic shunt, since it restores hepatopedal blood flow through the liver. This report describes the use of this shunt in an adult who had frequent gastrointestinal bleeding secondary to extrahepatic portal vein thrombosis, which occurred as a complication after a pancreaticoduodenectomy.

Shunt diameter in agenesis of the ductus venosus with extrahepatic portosystemic shunt impacts on prognosis

Agenesis of the ductus venosus (ADV) is a rare condition in which there are two variants of umbilical vein drainage: intrahepatic shunt or extrahepatic (portosystemic) shunt. It has been posited that the extrahepatic variant carries a poorer prognosis. However, in the absence of associated anomalies there is still a wide variation in outcome. We evaluated the portal system in cases of ADV and aimed to identify parameters that might predict outcome. We conducted a retrospective study of cases of ADV with extrahepatic shunt that had been examined in two centers, and collected new cases prospectively. The route of the shunt was depicted using two-dimensional (2D) and three-dimensional (3D) ultrasound imaging. In an attempt to characterize portal system and shunt developmental variations and their possible impact on outcome, the diameter of the shunt was compared with the diameter of the umbilical vein and the entire portal vasculature was assessed. Poor outcome was defined as persistent morbidity or fetal or neonatal death. Twenty-two cases of ADV were identified: nine retrospectively and 13 prospectively. Aberrant shunts from the umbilical vein were identified to the right atrium, coronary sinus, inferior vena cava (IVC) and iliac vein. In seven of 22 cases (32%) a wide connection was observed. In six of these seven cases (86%) the outcome was poor, including four with severe associated anomalies and two with hepatic dysfunction. In five of these cases, cardiomegaly with tricuspid regurgitation was observed, as well as underdevelopment of the portal system. In only five of 15 cases with a narrow shunt (33%) was the outcome poor, and in all five cases the poor outcome was related to associated anomalies. In cases of ADV with extrahepatic shunt, portal system development is impacted by the diameter of the shunt. If the shunt is narrow, the portal system will have developed normally. A wide shunt is associated with underdevelopment or absence of the portal system. In cases of ADV with extrahepatic shunt, prognosis is determined by the severity of associated anomalies, the diameter of the shunt and development of the portal system.