Intrahepatic Portosystemic Shunt Research Articles

A mattress suture with pledgets can partially occlude intrahepatic shunts in 23 dogs: evaluation of long-term survival.

To explore the differences in outcomes between dogs with intrahepatic portosystemic shunts (IHPSSs) partially occluded with a mattress suture with pledgets or attenuated with cellophane banding. 74 dogs with IHPSSs were included in this retrospective study. Medical records between January 2000 and February 2020 were evaluated for information on dogs undergoing laparotomy with cellophane banding (group C) or mattress suture with pledgets (group P) for treatment of IHPSSs, including specific outcomes of survival time, persistence of clinical signs, and necessity of continued medical management. Primary veterinarians and owners were contacted for long-term follow-up. 51 dogs were entered in group C and 23 in group P. The duration of surgery was 154.6 minutes (136.3 to 170 minutes) for group C and 154.9 minutes (128.9 to 180.9 minutes) for group P. The short-term mortality rate was 2% for group C and 4% for group P. Dogs in group C had a median survival time of 3,537 days, while dogs in group P had a median survival time of 2,141 days. In the long term, dogs in group P received more medications than dogs in group C, but the distribution of the quality-of-life score was not different. Mattress suture with pledgets can be used as an alternative to cellophane banding. For dogs with IHPSSs where full surgical dissection for placement of cellophane band is not possible, partial occlusion of the shunt with a mattress suture with pledgets is a viable option with acceptable long-term outcomes.

Membranoproliferative glomerulonephritis in a child with congenital portosystemic shunt.

Congenital portosystemic shunts (CPSS) are rare congenital vascular anomalies characterized by abnormal connections between the portal vein and systemic circulation, bypassing the liver. They can lead to complications such as recurrent encephalopathy, liver nodules, portopulmonary hypertension, and neurocognitive issues due to hyperammonemia and rarely kidney involvement. Hepatic hemodynamic changes can lead to liver nodules and hepatocellular carcinoma, particularly in extrahepatic shunts. We describe here an 11-year-old girl with type 1 intrahepatic portosystemic shunt with focal nodular hyperplasia in the liver, presenting with nephrotic syndrome that was diagnosed as membranoproliferative glomerulonephritis on kidney biopsy and that responded partially to therapy with immunosuppressants.

Comparison of hematologic variables between dogs with congenital intrahepatic and extrahepatic portosystemic shunts.

Dogs with congenital intrahepatic portosystemic shunt (IHPSS) are predisposed to gastrointestinal inflammation, ulceration, and bleeding, unlike dogs with congenital extrahepatic portosystemic shunt (EHPSS). Limited information is available about hematologic differences between dogs with IHPSS and dogs with EHPSS. Compare hemogram variables between dogs with IHPSS and EHPSS. We hypothesized that hematologic variables would differ between the 2 populations, with a higher frequency and severity of anemia and microcytosis in dogs with IHPSS. Twenty-six client-owned dogs with IHPSS and 35 client-owned dogs with EHPSS. Retrospective cross-sectional study. Dogs were included if a CBC was performed before shunt attenuation. Contingency analysis was performed to determine if the frequency of clinical signs and of hematologic variables below the reference range differed between groups. Hematologic and selected biochemical variables were compared between groups using an analysis of covariance with age as a covariate. Gastrointestinal clinical signs (IHPSS, 81% vs EHPSS, 34%; P = .01), anemia (31% vs 6%; P = .01), microcytosis (77% vs 29%; P = .002), and hypochromia (77% vs 49%; P = .03) were more common in dogs with IHPSS than in dogs with EHPSS. Dogs with IHPSS had lower packed cell volume (34% vs 41%, P = .04), hemoglobin concentration (11.5 g/dL vs 13.7 g/dL, P = .03), mean corpuscular volume (57 fL vs 65 fL; P = .001), and mean corpuscular hemoglobin concentration (32 g/dL vs 33 g/dL; P = .04) than dogs with EHPSS. Dogs with IHPSS had a higher frequency of anemia, microcytosis, and hypochromia and exhibited more gastrointestinal clinical signs.

Diagnosis and classification of portosystemic shunts: a machine learning retrospective case-control study.

Diagnosis of portosystemic shunts (PSS) in dogs often requires multiple diagnostic tests, and available clinicopathologic tests have limitations in sensitivity and specificity. The objective of this study was to train and validate a machine learning model (MLM) that can accurately predict the presence of a PSS utilizing routinely collected demographic data and clinicopathologic features. Dogs diagnosed with PSS or control dogs tested for PSS but had the condition ruled out (non-PSS) were identified. Dogs were included if a complete blood count and serum chemistry panel were available from PSS diagnostic testing. Dogs with a PSS were subcategorized as having a single intrahepatic PSS, a single extrahepatic PSS, or multiple extrahepatic PSS. An extreme gradient boosting (XGboost) MLM was trained with data from 70% of the cases, and MLM performance was determined on the test set, comprising the remaining 30% of the case data. Two MLMs were created. The first was designed to predict the presence of any PSS (PSS MLM), and the second to predict the PSS subcategory (PSS SubCat MLM). The trained PSS MLM had a sensitivity of 94.3% (95% CI 90.1-96.8%) and specificity of 90.5% (95% CI 85.32-94.0%) for dogs in the test set. The area under the receiver operator characteristic curve (AUC) was 0.976 (95% CI; 0.964-0.989). The mean corpuscular hemoglobin, lymphocyte count, and serum globulin concentration were most important in prediction classification. The PSS SubCat MLM had an accuracy of 85.7% in determining the subtype of PSS of dogs in the test set, with variable sensitivity and specificity depending on PSS subtype. These MLMs have a high accuracy for diagnosing PSS; however, the prediction of PSS subclassification is less accurate. The MLMs can be used as a screening tool to increase or decrease the index of suspicion for PSS before confirmatory diagnostics such as advanced imaging are pursued.

Comparison of two-dimensional imaging to three-dimensional modeling of intrahepatic portosystemic shunts using computed tomography angiography.

Computed tomography angiography (CTA) is used for the diagnosis of intrahepatic portosystemic shunts (IHPSS). When planning for transcatheter intervention, caudal vena cava (CVC) measurements are typically obtained from two-dimensional (2D) imaging to aid in stent selection. We hypothesized that clinically applicable three-dimensional (3D) IHPSS models can be generated, and CVC measurements will not differ between 2D images and 3D models. Computed tomography angiography datasets from client-owned dogs with IHPSS at the University of Georgia Veterinary Teaching Hospital from 2016 to 2022 were analyzed. Materialise Mimics 25.0 and 3-matic 17.0 were used for 3D modeling. Caudal vena cava diameters were measured in 2D dorsal and transverse planes 20mm cranial and caudal from the shunt ostium and were compared with CVC diameters from 3D models. Length was measured in the 2D dorsal plane between midpoints of each diameter and compared to the 3D model length. Data are presented as mean (SD), and intraclass correlation coefficients were performed. Three-dimensional models were generated for 32 IHPSS (15 right-, 12 left-, and five central-divisional). Two-dimensional dorsal and transverse area-associated diameter measurements were 16.7mm (5.6) and 15.5mm (4.2) cranial; 14.9mm (4.2) and 14.3mm (3.7) caudal. Three-dimensional area-associated diameter measurements were 15.3mm (4.4) cranial and 14.0mm (3.6) caudal. The 2D length was 61.5mm (7.1) compared with 3D 59.9mm (7.2). Intraclass correlation coefficients comparing 2D and 3D diameters were all >0.80, indicating very good agreement, with good agreement (>0.60) for length. Clinically applicable 3D IHPSS models can be generated using engineering software. Measurements from 3D models are consistent with 2D planar imaging. Both 2D CTA and 3D virtual models can be utilized for preprocedural planning, depending on clinician preference.

Intrahepatic portosystemic shunts, from prenatal diagnosis to postnatal outcome: a retrospective study

ObjectiveCongenital intrahepatic portosystemic shunts (IHPSS) are rare vascular malformations resulting in blood bypassing the liver to the systemic circulation. Previous studies included symptomatic patients diagnosed postnatally, but the outcome of...

Canine intrahepatic portosystemic shunts: Interlobar and intralobar classifications.

This two-part study design showed that a canine congenital intrahepatic portosystemic shunt (IPSS) may be classified by its location within a liver fissure (interlobar) or lobe (intralobar). A prospective anatomic study reviewed normal canine liver morphology and showed the CT angiography (CTA) appearance of the normal canine ductus venosus (DV), which was confirmed via dissection and literature review to be between the papillary process and left-lateral liver lobe (in the fissure for ligamentum venosum). A retrospective multi-institutional case series documented the frequency of imaging findings in 56 dogs with a single IPSS that underwent portal CTA at Cornell University or the Schwarzman Animal Medical Center between June 2008 and August 2022. An interlobar IPSS was seen in 24 of 56 (43%) dogs, all arose from the left portal branch except one. These shunts were typically near the median plane, remained interlobar throughout the course, and were nearly always (96%) craniodorsal to the porta hepatis. Four types were distinguished: patent DV (11 dogs), left interlobar (11 dogs), right interlobar (1 dog), and ventral interlobar (1 dog). Only about half (46%) were in the fissure for ligamentum venosum and therefore classified as a patent DV. An intralobar IPSS was seen in 32 of 56 (57%) dogs, most (88%) originated from the right portal branch and were in the right-lateral liver lobe (21 dogs) or caudate process (7 dogs). During canine portal CTA, documenting the interlobar or intralobar location of an IPSS might increase the consistency and validity of IPSS description.

Combined transjugular/percutaneous intrahepatic portosystemic shunts (cTIPS) for cavernous transformation of the portal vein after conventional transjugular approach TIPS failure.

This study aim was to compare the safety and efficacy of combined transjugular/percutaneous intrahepatic portosystemic shunts (cTIPS) and transjugular intrahepatic portosystemic shunt (TIPS) in cirrhotic patients with cavernous transformation of the portal vein (CTPV) after conventional transjugular approach TIPS failure. Cirrhotic patients who were diagnosed as CTPV and treated by cTIPS or TIPS between July 2012 and April 2022 were retrospectively analyzed. Patients' characteristics and clinical data were recorded. The clinical outcomes, long-term survival rates and patency rates between the 2 groups were compared. A total of 68 patients with CTPV were enrolled, of whom 23 were treated with TIPS and 45 with cTIPS. The initial technical success was 30.9% in TIPS group and 91.1% in cTIPS group. The hospitalization days increased significantly in the cTIPS group compared with TIPS group (P = .0131). However, the complication rate, patency rates and survival rates were similar between the 2 groups. In conclusion, cTIPS appeared to be safe and effective in cirrhotic patients with CTPV after conventional transjugular approach TIPS failure.

Endoscopic ultrasound-guided vascular interventions: An expanding paradigm.

Endoscopic ultrasound (EUS) has expanded its arena from a mere diagnostic modality to an essential therapeutic tool in managing gastrointestinal (GI) diseases. The proximity of the GI tract to the vascular structures in the mediastinum and the abdomen has facilitated the growth of EUS in the field of vascular interventions. EUS provides important clinical and anatomical information related to the vessels' size, appearance and location. Its excellent spatial resolution, use of colour doppler with or without contrast enhancement and ability to provide images "real-time" helps in precision while intervening vascular structures. Additionally, structures such as venous collaterals or varices can be dealt with optimally using EUS. EUS-guided vascular therapy with coil and glue combination has revolutionized the management of portal hypertension. It also helps to avoid radiation exposure in addition to being minimally invasive. These advantages have led EUS to become an upcoming modality to complement traditional interventional radiology in the field of vascular interventions. EUS-guided portal vein (PV) access and therapy is a new kid on the block. EUS-guided portal pressure gradient measurement, injecting chemotherapy in PV and intrahepatic portosystemic shunt has expanded the horizons of endo-hepatology. Lastly, EUS has also forayed into cardiac interventions allowing pericardial fluid aspiration and tumour biopsy with experimental data on access to valvular apparatus. Herein, we provide a comprehensive review of the expanding paradigm of EUS-guided vascular interventions in GI bleeding, portal vein access and its related therapeutic interventions, cardiac access, and therapy. A synopsis of all the technical details involving each procedure and the available data has been tabulated, and the future trends in this area have been highlighted.

Correlation of Prenatal and Postnatal Diagnosis in Umbilical-Portal-Systemic Venous Shunts.

Umbilical-portal-systemic venous shunts (UPSVS) are rare anomalies in the development of the fetal venous system. There are several postnatal and prenatal classifications of hepatic venous anomalies but the link between them is missing. We aimed to review the prenatal to postnatal diagnosis correlation in UPSVS at our center. It is a retrospective study of patients diagnosed with UPSVS between 2019 and 2021 at our institution. Demographic, obstetric, genetic, and neonatal data were reviewed with special focus on prenatal and postnatal ultrasounds. A total of seven patients were diagnosed with UPSVS at a median of 24 (20-34) weeks of gestational age. All patients were male and 62% were Caucasian. None of the patients had chromosomopathies or cardiac anomalies. One patient had renal ectopia, another one had a single umbilical artery, and a third one suffered from intrauterine growth retardation. An umbilico-systemic shunt (USS) was found in two patients and a ductus venosus-systemic shunt (DVSS) in the rest. Patients with USS were diagnosed postnatally with intrahepatic portosystemic shunts. One of the DVSS patients was transferred to another hospital and the other four had normal postnatal cardiac ultrasounds, with normal abdominal ultrasounds in two patients and lack of postnatally abdominal control in the other two. All babies were found to be doing well at a median follow-up of 1 month (0-24). There is a knowledge gap in the natural history of UPSVS between fetal and neonatal life. Building bridges between prenatal and postnatal research is mandatory in order to understand these rare anomalies.

Percutaneous transvenous coil embolization of congenital intrahepatic portosystemic shunts in small- and toy-breed dogs: 20 cases (2015-2021).

To describe outcomes of small- and toy-breed dogs with a congenital intrahepatic portosystemic shunt (IHPSS) treated with percutaneous transvenous coil embolization (PTCE). 20 small- and toy-breed dogs with an IHPSS. All dogs underwent CT angiography for shunt evaluation as well as PTCE. Medical records were reviewed for pertinent data, and owners and primary veterinarians were contacted for long-term follow-up information. Dogs ranged from 1.5 to 10.0 kg (mean ± SD, 6.32 ± 2.57 kg) in weight. The equipment used to perform PTCE tended to be smaller than that previously described for larger breed dogs. Intra- and postoperative complication rates were 20% (4/20) and 5% (1/20), respectively, and included hypotension, bradycardia, hypercapnia, ventricular premature contractions, hypothermia, and regurgitation. Dogs were discharged a median of 3 days (range, 1 to 3 days) after surgery, and all dogs survived to discharge. Clinical signs resolved in 95% (19/20) of the dogs a median of 21 days after the procedure. One- and 2-year survival rates were 92%. Three dogs had died by the time of data collection; 2 of these dogs died of causes related to the IHPSS 267 and 1,178 days, respectively, after the procedure. Percutaneous transvenous coil embolization was a safe and effective option for treatment of IHPSS in small- and toy-breed dogs and offered a minimally invasive alternative to open surgical techniques. Complication and survival rates in this cohort were similar to or better than those reported in previous studies evaluating PTCE and open surgical techniques for treatment of IHPSS in dogs.

Infra-cardiac TAPVC with an intrahepatic portosystemic shunt: A rare association.

Total anomalous pulmonary venous connection (TAPVC) is an uncommonly encountered cyanotic congenital heart disease characterized by anomalous drainage of the pulmonary veins. Concomitant venous anomalies are rarely found in these patients. We present a case of an infra-cardiac TAPVC with an intrahepatic portosystemic shunt, where a vascular channel was seen between the middle hepatic vein and the left branch of the portal vein with fusiform dilatation of the latter, diagnosed on computed tomography angiography.

Surgical treatment and outcome of intrahepatic shunts in 12 cats.

The objective of this case series was to describe the presentation, surgical treatment and outcome of a congenital intrahepatic portosystemic shunt (IHPSS) in 12 cats. A retrospective case series of cats undergoing surgical treatment for an IHPSS was undertaken. Signalment, clinical signs, imaging, surgical treatment, complications and short-term outcome (<30 days) were obtained using medical records. Long-term outcome (>1 year after first surgery) was obtained, where possible, using a health-related quality of life owner questionnaire. Seven cats were diagnosed with a left divisional shunt, three with a central divisional shunt and two with a right divisional shunt using intraoperative mesenteric portovenography. Three cats tolerated complete acute suture attenuation, eight cats underwent partial suture attenuation, four of which received complete suture ligation at a second surgery, and one cat underwent partial attenuation with a thin film band. Six cats (50%) developed post-attenuation neurological signs (PANS) after first surgery and two cats (17%) died or were euthanased due to severe PANS. Long-term outcome was available for eight cats (67%), with a median follow-up time of 1743 days (range 364-2228), and was described as excellent in five cats (63%), fair in two cats (25%) and poor in one cat (12%). Few papers exist that describe the presentation, intraoperative imaging, treatment and outcome of IHPSSs in cats. This is the first to describe surgical attenuation with a thin film band in a cat with an IHPSS. This case series reports excellent long-term outcomes in a majority of surgically treated cats with IHPSS.

FRI524 - Transjugular, intra-hepatic portosystemic shunt (TIPS) in elderly patients: preliminary analysis of a multi center retrospective cohort

FRI524 - Transjugular, intra-hepatic portosystemic shunt (TIPS) in elderly patients: preliminary analysis of a multi center retrospective cohort

Abernethy malformation: A comprehensive review.

Abernethy malformation is a rare condition in which portomesenteric blood bypasses the liver and drains into the systemic vein through a partial or complete shunt. It is categorised into two types on the basis of the shunt pattern between the portal vein and systemic vein. Abernethy malformation is associated with multiple congenital anomalies and acquired complications. A detailed understanding of anatomy and embryology is a prerequisite to interpret the imaging findings. Computed tomography and magnetic resonance angiography can delineate the shunt anatomy and evaluate the concomitant malformations. It is essential to differentiate Abernethy malformation from intrahepatic portosystemic shunts and acquired extrahepatic portosystemic shunts. Mild metabolic abnormalities are treated with dietary modifications and medical therapy. Definitive treatment is done in symptomatic patients. Generally, type I Abernethy patients undergo liver transplantation, and type II undergo shunt occlusion by surgery or transcatheter coiling.

Case Report: Clinical Features of Congenital Portosystemic Shunts in the Neonatal Period

Objective: The aim of this single-center retrospective study was to analyze the clinical characteristics, treatment options, and course of neonatal-onset congenital portosystemic shunts (CPSS).Methods: We included all patients with CPSS who presented with clinical symptoms within the neonatal period in our institution between 2015 and 2020.Results: Sixteen patients were identified, including 13 patients with intrahepatic portosystemic shunts (IPSS) and three patients with extrahepatic portosystemic shunts (EPSS). The median age of diagnosis was 16 days (range prenatal 24 weeks−12 months). Hyperammonemia (60%), neonatal cholestasis (44%), elevated liver enzyme (40%), hypoglycemia (40%), thrombocytopenia (38%), and coagulation abnormalities (23%) appeared in neonatal CPSS. Twelve patients (75%) presented with congenital anomalies, of which congenital heart disease (CHD) (44%) was the most common. Thirteen patients with IPSS initially underwent conservative treatment, but two of them were recommended for the catheter interventional therapy and liver transplantation, respectively, due to progressive deterioration of liver function. Spontaneous closure occurred in nine patients with IPSS. The shunt was closed using transcatheter embolization in one patient with EPSS type II. Another patient with EPSS type II underwent surgical treatment of CHD firstly. The remaining patient with EPSS type Ib received medical therapy and refused liver transplantation.Conclusion: Hyperammonemia, neonatal cholestasis, elevated liver enzyme, hypoglycemia, and thrombocytopenia are the main complications of neonatal CPSS. Moreover, CPSS is associated with multiple congenital abnormalities, especially CHD. Intrahepatic portosystemic shunts may close spontaneously, and conservative treatment can be taken first. Extrahepatic portosystemic shunts should be closed to prevent complications.

Intrahepatic venous collaterals in dogs with congenital intrahepatic portosystemic shunts are associated with focal shunt or hepatic vein narrowing

Dogs with congenital intrahepatic portosystemic shunts (IHPSS) occasionally have multiple smaller intrahepatic, tortuous blood vessels surrounding the primary shunt. This study was a retrospective, observational design that was also descriptive and anatomic in nature. Objectives were to characterize vascular morphology in IHPSS dogs presenting with intrahepatic venous collaterals (IVCs) relative to IHPSS dogs without IVCs, and to propose reasons for IVC development. The authors hypothesized that (a) IVCs develop secondary to flow resistance around a focal area of a shunt or draining hepatic vein narrowing and (b) the presence of IVC is associated with portal vessel development before intervention. Anonymized CT angiograms (CTA) and fluoroscopic portovenograms (FPV) of dogs with IHPSS were evaluated for the presence of IVCs, focal narrowing within the IHPSS, and intrahepatic portal vessels>5mm long. Eleven of 47 (23%) dogs had IVCs identified. IVCs were significantly associated with focal narrowing in the shunt or draining hepatic vein on CTA (P=0.039) and FPV (P=0.021). IVCs were not associated with the presence of intrahepatic portal branches>5mm long on portovenography (P=0.42) or CTA (P=0.49). Focal narrowing in the shunt (circumferential soft tissue narrowing>20% of the shunt diameter) was significantly associated with intrahepatic portal branches>5mm long on both modalities (P<0.001). IVCs are associated with focal narrowing of the shunt or draining hepatic vein in dogs with IHPSS. IVC should be distinguished from other conditions when evaluating a CTA for canine IHPSS.

Protein C and comparative biochemical changes in dogs treated with percutaneous transvenous coil embolization of congenital intrahepatic portosystemic shunts.

To evaluate protein C (PC) activity after intrahepatic portosystemic shunt (IHPSS) percutaneous transvenous coil embolization (PTCE) in dogs; to identify if PC is associated with clinical status after intervention, and to compare PC with standard biochemical values. Retrospective case series. Forty-seven client-owned dogs with IHPSS undergoing PTCE. Records were reviewed for preoperative and postoperative PC, hematocrit (HCT), mean corpuscular volume (MCV), albumin (ALB), and blood urea nitrogen (BUN). Ultimate clinical status was classified as excellent, fair, or poor, based on ongoing medical management and the presence of clinical signs. Intrahepatic portosystemic shunt was considered to be completely or incompletely occluded intraoperatively based on angiography. Postoperative PC activity increased in 37/47 (78.7%) dogs with a mean increase of 38.7% ± 2.1%. Ultimate postoperative clinical status was excellent in 16/43 (37.2%), fair in 19/43 (44.2%), and poor in 8/43 dogs (18.6%). No association was detected between preoperative PC (46.8% ± 1.8%) and ultimate clinical status but mean postoperative PC (75.7% ± 1.4%), HCT, MCV, ALB, and BUN were higher in dogs with excellent clinical status. Postoperative PC activity was higher when shunts were completely occluded (96.3% ± 10.9%), which was a finding associated with excellent status. Postoperative, but not preoperative, PC activity was higher in dogs with better ultimate clinical status. Similar trends were noted in standard hematological and biochemical values. Complete occlusion of shunts was associated with a higher postoperative PC and superior ultimate clinical status. Postoperative PC may provide valuable information about the success of PTCE for IHPSS as it relates to the ultimate status and the need for additional procedures.

S1212 Nutritional Deficiencies in Decompensated Cirrhotics with Hepatic Encephalopathy

Introduction: Hepatic encephalopathy (HE) is a major complication of end-stage cirrhosis. Predisposing factors include infection, electrolyte imbalances, constipation, and GI bleeding. HE has also been associated with nutritional deficiencies which might be secondary to inadequate diet, such as protein deficiency, gut malabsorption, and decreased hepatic storage. In particular, zinc deficiency hinders the metabolism of ammonia, thus causing buildup and contributing to worsening of HE.1 We aimed to assess the frequency in which vitamins and zinc were tested in our decompensated cirrhotic population with HE. Methods: We performed a retrospective review of 145 patients with decompensated cirrhosis that were seen in an outpatient hepatology clinic from January 2020 to May 2021. Patient demographics, decompensations and management were recorded. Nutrients that were evaluated included zinc, vitamin B12, and thiamine. Results: Out of 145 patients, 73 were found to have HE. 33/73 were male, and the average MELD score was 15.5 ± 6.3. 32 patients had NASH cirrhosis, 22 had alcoholic cirrhosis, 9 had hepatitis B, C or both and 9 had other diagnoses. For the management of HE, 27 patients were on lactulose, 35 on lactulose and rifaximin, 8 on only rifaximin and 3 on other regimens. Intrahepatic portosystemic shunt (TIPS) placement was found in 8 patients. Average albumin level was 3.35 ± 0.6 g/dL. Amongst patients with HE, 17/23 (74%) were deficient in zinc (< 60 mcg/dL) . Thiamine deficiency was found in 75% of the patients, with 11/32 (34%) low (8-30 nMol/L), and 13/32 (41%) severely low in Thiamine (< 8 nMol/L). B12 deficiency (< 300 pg/mL) was found in 2/47 (4%) patients. Conclusion: Deficiency in certain vitamins and zinc can worsen symptoms associated with HE in patients with cirrhosis. Our study demonstrated that zinc, vitamin B12, and thiamine levels are commonly low in these patients, and that providers should evaluate and optimize patients with HE from a nutritional perspective. Further studies are needed to determine if routine testing and treatment for these elements have a positive impact on the clinical trajectory of HE.

Ferumoxytol-enhanced magnetic resonance angiography provides comparable vascular conspicuity to CT angiography in dogs with intrahepatic portosystemic shunts.

Computed tomography angiography (CTA) is currently the gold standard imaging modality for anatomically characterizing canine hepatic vascular anomalies; with conventional, gadolinium-enhanced MR angiography being less frequently utilized. However, both imaging modalities are limited by a brief, first pass peak of contrast medium in the vasculature that necessitates precisely timed image acquisition. A long-acting purely intravascular magnetic resonance imaging (MRI) contrast agent, ferumoxytol, offers the potential to reduce complexity of magnetic resonance angiography (MRA) protocol planning by ensuring diagnostic contrast medium concentration in all the vessels that are targeted for imaging. Aims of this prospective, pilot, methods comparison study were to develop an optimized MRA protocol using ferumoxytol in dogs with hepatic vascular anomalies, perform a dose escalation trial to compare image quality with four-dose regimens of ferumoxytol, and compare accuracy of vascular anatomic depiction based on the gold standard of CTA. Six dogs (10.7-36.1kg) with portosystemic shunts (four intrahepatic left divisional shunts and two intrahepatic right divisional shunts) were recruited for inclusion in the study. A dose-escalation trial was performed to compare image quality at four incremental dose levels of ferumoxytol (1, 2, 3, and 4mg/kg) and to compare the accuracy of vascular anatomic detection to CTA. Ferumoxytol contrast-enhanced MRA (CE-MRA) at 4mg/kg provided similar conspicuity of normal and abnormal vasculature compared to CTA with a minimal decrease in spatial resolution. Findings indicated that ferumoxytol holds promise for comprehensive, single breath hold CE-MRA of all abdominal vessels in dogs with portosystemic shunts. Background information provided in this study can be used to support development of other future applications such as intracranial and cardiac MRA, real-time imaging, flow quantification, and potentially sedated MRI imaging.