Superiority of Step-up Approach vs Open Necrosectomy in Long-term Follow-up of Patients With Necrotizing Pancreatitis.

BACKGROUND & AIMS: In a 2010 randomized trial (the PANTER trial), a surgical step-up approach for infected necrotizing pancreatitis was found to reduce the composite endpoint of death or major complications compared with open necrosectomy; 35% of patients were successfully treated with simple catheter drainage only. There is concern, however, that minimally invasive treatment increases the need for reinterventions for residual peripancreatic necrotic collections and other complications during the long term. We therefore performed a long-term follow-up study. METHODS: We reevaluated all the 73 patients (of the 88 patients randomly assigned to groups) who were still alive after the index admission, at a mean 86 months (±11 months) of follow-up. We collected data on all clinical and health care resource utilization endpoints through this follow-up period. The primary endpoint was death or major complications (the same as for the PANTER trial). We also measured exocrine insufficiency, quality of life (using the Short Form-36 and EuroQol 5 dimensions forms), and Izbicki pain scores. RESULTS: From index admission to long-term follow-up, 19 patients (44%) died or had major complications in the step-up group compared with 33 patients (73%) in the open-necrosectomy group (P = .005). Significantly lower proportions of patients in the step-up group had incisional hernias (23% vs 53%; P = .004), pancreatic exocrine insufficiency (29% vs 56%; P = .03), or endocrine insufficiency (40% vs 64%; P = .05). There were no significant differences between groups in proportions of patients requiring additional drainage procedures (11% vs 13%; P = .99) or pancreatic surgery (11% vs 5%; P = .43), or in recurrent acute pancreatitis, chronic pancreatitis, Izbicki pain scores, or medical costs. Quality of life increased during follow-up without a significant difference between groups. CONCLUSIONS: In an analysis of long-term outcomes of trial participants, we found the step-up approach for necrotizing pancreatitis to be superior to open necrosectomy, without increased risk of reinterventions.

Endoscopic or surgical step-up approach for infected necrotising pancreatitis: a multicentre randomised trial.

BACKGROUND: Infected necrotising pancreatitis is a potentially lethal disease and an indication for invasive intervention. The surgical step-up approach is the standard treatment. A promising alternative is the endoscopic step-up approach. We compared both approaches to see whether the endoscopic step-up approach was superior to the surgical step-up approach in terms of clinical and economic outcomes. METHODS: In this multicentre, randomised, superiority trial, we recruited adult patients with infected necrotising pancreatitis and an indication for invasive intervention from 19 hospitals in the Netherlands. Patients were randomly assigned to either the endoscopic or the surgical step-up approach. The endoscopic approach consisted of endoscopic ultrasound-guided transluminal drainage followed, if necessary, by endoscopic necrosectomy. The surgical approach consisted of percutaneous catheter drainage followed, if necessary, by video-assisted retroperitoneal debridement. The primary endpoint was a composite of major complications or death during 6-month follow-up. Analyses were by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN09186711. FINDINGS: Between Sept 20, 2011, and Jan 29, 2015, we screened 418 patients with pancreatic or extrapancreatic necrosis, of which 98 patients were enrolled and randomly assigned to the endoscopic step-up approach (n=51) or the surgical step-up approach (n=47). The primary endpoint occurred in 22 (43%) of 51 patients in the endoscopy group and in 21 (45%) of 47 patients in the surgery group (risk ratio [RR] 0·97, 95% CI 0·62-1·51; p=0·88). Mortality did not differ between groups (nine [18%] patients in the endoscopy group vs six [13%] patients in the surgery group; RR 1·38, 95% CI 0·53-3·59, p=0·50), nor did any of the major complications included in the primary endpoint. INTERPRETATION: In patients with infected necrotising pancreatitis, the endoscopic step-up approach was not superior to the surgical step-up approach in reducing major complications or death. The rate of pancreatic fistulas and length of hospital stay were lower in the endoscopy group. The outcome of this trial will probably result in a shift to the endoscopic step-up approach as treatment preference. FUNDING: The Dutch Digestive Disease Foundation, Fonds NutsOhra, and the Netherlands Organization for Health Research and Development.

Describing Peripancreatic Collections According to the Revised Atlanta Classification of Acute Pancreatitis: An International Interobserver Agreement Study.

OBJECTIVES: Severe acute pancreatitis is associated with peripancreatic morphologic changes as seen on imaging. Uniform communication regarding these morphologic findings is crucial for accurate diagnosis and treatment. For the original 1992 Atlanta classification, interobserver agreement is poor. We hypothesized that for the revised Atlanta classification, interobserver agreement will be better. METHODS: An international, interobserver agreement study was performed among expert and nonexpert radiologists (n = 14), surgeons (n = 15), and gastroenterologists (n = 8). Representative computed tomographies of all stages of acute pancreatitis were selected from 55 patients and were assessed according to the revised Atlanta classification. The interobserver agreement was calculated among all reviewers and subgroups, that is, expert and nonexpert reviewers; interobserver agreement was defined as poor (≤0.20), fair (0.21-0.40), moderate (0.41-0.60), good (0.61-0.80), or very good (0.81-1.00). RESULTS: Interobserver agreement among all reviewers was good (0.75 [standard deviation, 0.21]) for describing the type of acute pancreatitis and good (0.62 [standard deviation, 0.19]) for the type of peripancreatic collection. Expert radiologists showed the best and nonexpert clinicians the lowest interobserver agreement. CONCLUSIONS: Interobserver agreement was good for the revised Atlanta classification, supporting the importance for widespread adaption of this revised classification for clinical and research communications.

Imaging of perihilar cholangiocarcinoma.

OBJECTIVE: The purpose of this article is to review imaging workup of perihilar cholangiocarcinoma, including MDCT and MRI protocols, imaging findings, differential diagnosis, and staging. A reporting template is included. CONCLUSION: Imaging plays a central role in the detection, differential diagnosis, and staging of perihilar cholangiocarcinoma.

Percutaneous treatment of common bile duct stones: results and complications in 110 consecutive patients.

BACKGROUND/AIMS: Choledocholithiasis is a common complication of cholecystolithiasis, occurring in 15-20% of patients who have gallbladder stones. Endoscopic retrograde cholangio-pancreatography is the standard treatment. When this is not possible or not feasible, percutaneous transhepatic stone removal is an alternative treatment. In this retrospective study, we analyze 110 patients who were treated with percutaneous transhepatic removal of Common Bile Duct (CBD) stones. PATIENTS AND METHODS: Between March 1998 and September 2013 110 patients (61 men, 49 women; aged 14-96, mean age 69.7 years) with confirmed bile duct stones were included. PTC was done using ultrasound and fluoroscopy. Balloon dilatation of the papilla was done with 8-12 mm balloons. If stone size exceeded 10 mm, mechanical lithotripsy was performed. Stones were then removed by percutaneous extraction or evacuation into the duodenum. RESULTS: In 104 patients (104/110; 94.5%) total stone clearance of the CBD was achieved. A total of 12 complications occurred (10.9%), graded with the Clavien-Dindo scale as IVa, IVb, and V, respectively; hypoxia requiring resuscitation, sepsis and death due to ongoing cholangiosepsis (n = 1, 4, 1). Minor complications I, II, and IIIa included: small liver abscess, pleural empyema, transient hemobilia and mild fever (n = 1, 1, 2, 2). CONCLUSION: Percutaneous removal of CBD stones is an effective alternative treatment, when endoscopic treatment is contra-indicated, fails or is not feasible. It is effective, has a low complication rate and using deep sedation potentially requires only a very limited number of treatment sessions.

Characterization and treatment of persistent hepatocellular secretory failure.

BACKGROUND & AIMS: Hepatocellular secretory failure induced by drugs, toxins or transient biliary obstruction may sometimes persist for months after removal of the initiating factor and may then be fatal without liver transplantation. We characterized patients with severe persistent hepatocellular secretory failure (PHSF) and treated them with the pregnane X receptor (PXR) agonist, rifampicin. We also studied the effect of rifampicin on PXR-dependent expression of genes involved in biotransformation and secretion in vitro. METHODS: Thirteen patients (age 18-81 years, 6 male) with hepatocellular secretory failure that persisted after removal of the inducing factor (drugs/toxin: 9) or biliary obstruction (4) were identified over 6 years. Six of these patients were screened for ATP8B1 or ABCB11 mutations. All were treated with rifampicin (300 mg daily) for 1-10 weeks. Expression of genes involved in biotransformation and secretion was determined by rtPCR in human hepatocytes and intestinal cells incubated with rifampicin (10 µmol/L). RESULTS: Serum bilirubin of patients with PHSF ranged from 264 to 755 µmol/L. Normal γGT was found in 10/13 patients of whom 3/6 tested positive for ATP8B1/ABCB11 mutations. Serum bilirubin declined to <33 µmol/L after 1-10 weeks of rifampicin treatment. In vitro, rifampicin PXR-dependently upregulated biotransformation phase 1 (CYP3A4), phase 2 (UGT1A1) and phase 3 (MRP2) enzymes/carriers as well as the basolateral bile salt exporter OSTß. CONCLUSION: Persistent hepatocellular secretory failure may develop in carriers of transporter gene mutations. In severe cases, rifampicin may represent an effective therapeutic option of PHSF. PXR-dependent induction of CYP3A4, UGT1A1, MRP2 and OSTß could contribute to the anticholestatic effect of rifampicin in PHSF.

Leukemia and brain tumors among children after radiation exposure from CT scans: design and methodological opportunities of the Dutch Pediatric CT Study.

Computed tomography (CT) scans are indispensable in modern medicine; however, the spectacular rise in global use coupled with relatively high doses of ionizing radiation per examination have raised radiation protection concerns. Children are of particular concern because they are more sensitive to radiation-induced cancer compared with adults and have a long lifespan to express harmful effects which may offset clinical benefits of performing a scan. This paper describes the design and methodology of a nationwide study, the Dutch Pediatric CT Study, regarding risk of leukemia and brain tumors in children after radiation exposure from CT scans. It is a retrospective record-linkage cohort study with an expected number of 100,000 children who received at least one electronically archived CT scan covering the calendar period since the introduction of digital archiving until 2012. Information on all archived CT scans of these children will be obtained, including date of examination, scanned body part and radiologist's report, as well as the machine settings required for organ dose estimation. We will obtain cancer incidence by record linkage with external databases. In this article, we describe several approaches to the collection of data on archived CT scans, the estimation of radiation doses and the assessment of confounding. The proposed approaches provide useful strategies for data collection and confounder assessment for general retrospective record-linkage studies, particular those using hospital databases on radiological procedures for the assessment of exposure to ionizing or non-ionizing radiation.

Percutaneous balloon dilatation and long-term drainage as treatment of anastomotic and nonanastomotic benign biliary strictures.

PURPOSE: This study was designed to determine the effectiveness of percutaneous balloon dilation and long-term drainage of postoperative benign biliary strictures. METHODS: Medical records of patients with postoperative benign biliary strictures, in whom percutaneous transhepatic biliary drainage (PTBD) and balloon dilation was performed between January 1999 and December 2011, were retrospectively reviewed. PTBD and balloon dilation (4-10 mm) were followed by placement of internal-external biliary drainage catheters (8.5-12 F). Patients were scheduled for elective tube changes, if necessary combined with repeated balloon dilation of the stenosis, at 3-week intervals up to a minimum of 3 months. RESULTS: Ninety-eight patients received a total of 134 treatments. The treatment was considered technically successful in 98.5%. Drainage catheters were left in with a median duration of 14 weeks. Complications occurred in 11 patients. In 13 patients, percutaneous treatment was converted to surgical intervention. Of 85 patients in whom percutaneous treatment was completed, 11.8% developed clinically relevant restenosis. Median follow-up was 35 months. Probability of patency at 1, 2, 5, and 10 years was 0.95, 0.92, 0.88, and 0.72, respectively. Overall, 76.5% had successful management with PTBD. Restenosis and treatment failure occurred more often in patients who underwent multiple treatments. Treatments failed more often in patients with multiple strictures. All blood markers of liver function significantly decreased to normal values. CONCLUSIONS: Percutaneous balloon dilation and long-term drainage demonstrate good short- and long-term effectiveness as treatment for postoperative benign biliary strictures with an acceptably low complication rate and therefore are indicated as treatment of choice.

Transluminal endoscopic step-up approach versus minimally invasive surgical step-up approach in patients with infected necrotising pancreatitis (TENSION trial): design and rationale of a randomised controlled multicenter trial [ISRCTN09186711].

BACKGROUND: Infected necrotising pancreatitis is a potentially lethal disease that nearly always requires intervention. Traditionally, primary open necrosectomy has been the treatment of choice. In recent years, the surgical step-up approach, consisting of percutaneous catheter drainage followed, if necessary, by (minimally invasive) surgical necrosectomy has become the standard of care. A promising minimally invasive alternative is the endoscopic transluminal step-up approach. This approach consists of endoscopic transluminal drainage followed, if necessary, by endoscopic transluminal necrosectomy. We hypothesise that the less invasive endoscopic step-up approach is superior to the surgical step-up approach in terms of clinical and economic outcomes. METHODS/DESIGN: The TENSION trial is a randomised controlled, parallel-group superiority multicenter trial. Patients with (suspected) infected necrotising pancreatitis with an indication for intervention and in whom both treatment modalities are deemed possible, will be randomised to either an endoscopic transluminal or a surgical step-up approach. During a 4 year study period, 98 patients will be enrolled from 24 hospitals of the Dutch Pancreatitis Study Group. The primary endpoint is a composite of death and major complications within 6 months following randomisation. Secondary endpoints include complications such as pancreaticocutaneous fistula, exocrine or endocrine pancreatic insufficiency, need for additional radiological, endoscopic or surgical intervention, the need for necrosectomy after drainage, the number of (re-)interventions, quality of life, and total direct and indirect costs. DISCUSSION: The TENSION trial will answer the question whether an endoscopic step-up approach reduces the combined primary endpoint of death and major complications, as well as hospital stay and related costs compared with a surgical step-up approach in patients with infected necrotising pancreatitis.

Short-term effects of combined hepatic vein embolization and portal vein embolization for the induction of liver regeneration in a rabbit model.

PURPOSE: Alternative methods to optimize the hypertrophy response after portal vein embolization (PVE) are desired. This study assessed the effect of hepatic vein embolization (HVE) in addition to PVE on liver hypertrophy response in a standardized rabbit model. MATERIALS AND METHODS: Thirty rabbits were allocated to groups according to intervention: PVE alone, HVE alone, and a combination of HVE and PVE. The liver regeneration response of the nonembolized, caudal liver was assessed by computed tomographic volumetry, liver-to-body weight index, and the amount of proliferating hepatocytes. RESULTS: The caudal liver volume (CLV) increased significantly more in the PVE and combined PVE/HVE group than in the HVE group at 3 and 7 days after the procedure (P < .01). There were no significant differences in CLV increase or degree of hypertrophy between the PVE and combined embolization groups. The caudal liver-to-body weight index was significantly higher in the PVE and combined embolization groups than in the HVE group on day 7 (P < .01). The index was also significantly higher in the combined PVE/HVE group compared with the PVE group (P = .008). The caudal liver tissue of the PVE and combined groups contained a significantly higher number of proliferating hepatocytes compared with the HVE group on day 7 (P < .01). CONCLUSIONS: Although histologic and additional regenerative changes are seen, HVE in addition to PVE has no additional short-term effect on hypertrophy response. The combination of HVE and PVE may therefore have little use in a clinical setting.

[Jaundice and a pancreatic tumour caused by auto-immune pancreatitis]. / Auto-immune pancreatitis als oorzaak van geelzucht en een tumor in het pancreas.

Three male patients aged between 50 and 70 years were referred with jaundice and weight loss. Imaging showed a pancreatic mass and changes in the calibre of the choledochal or pancreatic duct, suggestive of malignancy. Two patients were operated on. One patient was considered to have an unresectable carcinoma but showed remarkable clinical improvement after steroids were given for his poor condition. In the other patient a resection was performed. Histology showed IgG4-positive plasma cell infiltration without signs of malignancy. Eventually these patients were diagnosed with auto-immune pancreatitis (AIP). In the third patient AIP was considered beforehand and this patient was treated with steroids. He responded quickly both clinically and radiologically. CT imaging showed complete remission of the mass. AIP is a benign inflammatory process which can mimic pancreatic carcinoma. In doubtful cases, a short trial of steroids might be considered.

[Improved treatment results in hilar cholangiocarcinoma after transition to more extensive procedure: 20 years experience AMC]. / Betere behandelresultaten bij hilair cholangiocarcinoom na overgang op uitgebreidere ingreep: 20 jaar ervaring AMC.

OBJECTIVE: To determine the result of surgical treatment of patients with hilar cholangiocarcinoma (HCCA) before and after the transition from predominantly local bile duct resections to more extensive resections including partial liver resection in order to achieve complete tumour resection in the Academic Medical Center, Amsterdam (The Netherlands). DESIGN: Retrospective and descriptive. METHODS: In the period 1988-2003, 117 consecutive patients underwent resection due to suspected HCCA. Preoperative work-up included staging laparoscopy, preoperative biliary drainage and short-course radiation therapy (3 x 3.5 Gy) to prevent seeding metastases. A more extended multidisciplinary surgical approach combining bile duct resection with partial liver resection was applied as of 1998. Outcomes of resection including 5-year survival were assessed in patients who had undergone resection before (1988-1997; period 1) and after (1998-2003; period 2) this change in surgical approach. RESULTS: In 18 patients (15.3%) a benign lesion was found in the resection specimen. Among the other 99 patients with microscopically confirmed HCCA, 21 (72%) of 29 patients had undergone bile duct resection in combination with partial liver resection in period 2 as compared to 17 (24%) of 70 patients in period 1. The margin tumour free resection rate increased from 20% in period 1 to 59% in period 2. Five-year survival increased from 20% (SE: 5) in period 1, to 33% (SE: 9) in period 2. Morbidity and mortality in period 2 were 69% and 10%, respectively, as compared to 64% and 17% in period 1. CONCLUSION: More extensive resection of HCCA in combination with partial liver resection in the setting of a multidisciplinary approach led to a higher rate of margin free resections and improved 5-year survival.

Endothelial shear stress: a critical determinant of arterial remodeling and arterial stiffness in humans--a carotid 3.0-T MRI study.

BACKGROUND: Low endothelial shear stress (ESS) elicits endothelial dysfunction. However, the relationship between ESS and arterial remodeling and arterial stiffness is unknown in humans. We developed a 3.0-T MRI protocol to evaluate the contribution of ESS to arterial remodeling and stiffness. METHODS AND RESULTS: Fifteen young (aged 26 ± 3 years) and 15 older (aged 57 ± 3 years) healthy volunteers as well as 15 patients with cardiovascular disease (aged 63 ± 10 years) were enrolled. Phase-contrast MRI of the common carotid arteries was used to derive ESS data from the spatial velocity gradients close to the arterial wall. ESS measurements were performed on 3 occasions and showed excellent reproducibility (intraclass correlation coefficient, 0.79). Multiple linear regression analysis accounting for age and blood pressure revealed that ESS was an independent predictor of the following response variables: carotid wall thickness (regression coefficient [b], -0.19 mm(2) per N/m(2); P=0.02), lumen area (b, -15.5 mm(2) per N/m(2); P<0.001), and vessel size (b, -24.0 mm(2) per N/m(2); P<0.001). Segments of the artery wall exposed to lower ESS were significantly thicker than segments exposed to higher ESS within the same artery (P=0.009). Furthermore, ESS was associated with arterial compliance, accounting for age, blood pressure, and wall thickness (b, -0.003 mm(2)/mm Hg per N/m(2); P=0.04). CONCLUSIONS: Our carotid MRI data show that ESS is an important determinant of arterial remodeling and arterial stiffness in humans. The data warrant further studies to evaluate use of carotid ESS as a noninvasive tool to improve the understanding of individual cardiovascular disease risk and to assess novel drug therapies in cardiovascular disease prevention.

A step-up approach or open necrosectomy for necrotizing pancreatitis.

BACKGROUND: Necrotizing pancreatitis with infected necrotic tissue is associated with a high rate of complications and death. Standard treatment is open necrosectomy. The outcome may be improved by a minimally invasive step-up approach. METHODS: In this multicenter study, we randomly assigned 88 patients with necrotizing pancreatitis and suspected or confirmed infected necrotic tissue to undergo primary open necrosectomy or a step-up approach to treatment. The step-up approach consisted of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. The primary end point was a composite of major complications (new-onset multiple-organ failure or multiple systemic complications, perforation of a visceral organ or enterocutaneous fistula, or bleeding) or death. RESULTS: The primary end point occurred in 31 of 45 patients (69%) assigned to open necrosectomy and in 17 of 43 patients (40%) assigned to the step-up approach (risk ratio with the step-up approach, 0.57; 95% confidence interval, 0.38 to 0.87; P=0.006). Of the patients assigned to the step-up approach, 35% were treated with percutaneous drainage only. New-onset multiple-organ failure occurred less often in patients assigned to the step-up approach than in those assigned to open necrosectomy (12% vs. 40%, P=0.002). The rate of death did not differ significantly between groups (19% vs. 16%, P=0.70). Patients assigned to the step-up approach had a lower rate of incisional hernias (7% vs. 24%, P=0.03) and new-onset diabetes (16% vs. 38%, P=0.02). CONCLUSIONS: A minimally invasive step-up approach, as compared with open necrosectomy, reduced the rate of the composite end point of major complications or death among patients with necrotizing pancreatitis and infected necrotic tissue. (Current Controlled Trials number, ISRCTN13975868.)

Endoscopic and percutaneous preoperative biliary drainage in patients with suspected hilar cholangiocarcinoma.

INTRODUCTION: Controversy exists over the preferred technique of preoperative biliary drainage (PBD) in patients with hilar cholangiocarcinoma (HCCA) requiring major liver resection. The current study compared outcomes of endoscopic biliary drainage (EBD) and percutaneous transhepatic biliary drainage (PTBD) in patients with resectable HCCA. METHODS: One hundred fifteen consecutive patients were explored for HCCA between 2001 and July 2008 and assigned by initial PBD procedure to either EBD or PTBD. RESULTS: Of these patients, 101 (88%) underwent PBD; 90 patients underwent EBD as primary procedure, and 11 PTBD. The technical success rate of initial drainage was 81% in the EBD versus 100% in the PTBD group (P = 0.20). Stent dislocation was similar in the EBD and PTBD groups (23% vs. 20%, P = 0.70). Infectious complications were significantly more common in the endoscopic group (48% vs. 9%, P < 0.05). Patients in the EBD group underwent more drainage procedures (2.8 vs. 1.4, P < 0.01) and had a significantly longer drainage period until laparotomy (mean 15 weeks vs. 11 weeks in the PTBD group; P < 0.05). In 30 patients, EBD was converted to PTBD due to failure of the endoscopic approach. CONCLUSIONS: Preoperative percutaneous drainage could outperform endoscopic stent placement in patients with resectable HCCA, showing fewer infectious complications, using less procedures.

Comparison of in vivo carotid 3.0-T magnetic resonance to B-mode ultrasound imaging and histology in a porcine model.

OBJECTIVES: We compared in vivo 3.0-T magnetic resonance (MR) images of the carotid artery wall in piglets to intima-media thickness measurements of similar carotid segments by B-mode ultrasound (US) and histology to define the corresponding anatomical tissue characteristics and accuracy of carotid MR images. BACKGROUND: Carotid MR is increasingly used for the assessment of cardiovascular risk and cardiovascular drug efficacy. Therefore, determining the anatomical correlate and accuracy of this modality is of major importance. METHODS: In vivo 3.0-T MR and B-mode US scans of the left and right common carotid arteries were performed in 5 piglets (75 to 80 kg). The T(1)-weighted MR images were acquired with a noninterpolated pixel size of 0.25 x 0.25 mm for mean wall area (MWA) and mean wall thickness measurements. The B-mode US measured common carotid intima-media thickness and common carotid diameter. We calculated US MWA using common carotid intima-media thickness and carotid diameter. In histology, the intima and media tissue area was defined as histology MWA. RESULTS: Histology MWA was 4.69 (standard deviation [SD]: 0.95) mm(2), MR MWA was 4.57 (SD: 0.41) mm(2), and US MWA was 4.90 (SD: 0.50) mm(2). The mean difference was 0.12 (SD: 1.11) mm(2) for MR and -0.21 (SD: 1.01) mm(2) for US when compared with histology. Bland-Altman analysis showed no systematic biases between MR, US, or histology. CONCLUSIONS: Absolute values for carotid artery histology, MR, and US measurements are in good agreement, indicating that both 3.0-T MR and B-mode US measurements can visualize the intima and media. Accuracy of 3.0-T MR is comparable to B-mode US. The present findings imply that carotid MR might be a novel asset in cardiovascular disease risk stratification and a valuable surrogate marker in cardiovascular prevention trials.

Volumetric and functional recovery of the remnant liver after major liver resection with prior portal vein embolization : recovery after PVE and liver resection.

INTRODUCTION: Portal vein embolization is an accepted method to increase the future remnant liver preoperatively. The aim of this study was to assess the effect of preoperative portal vein embolization on liver volume and function 3 months after major liver resection. MATERIALS AND METHODS: This is a retrospective case-control study. Data were collected of patients who underwent portal vein embolization prior to (extended) right hemihepatectomy and of control patients who underwent the same type of resection without prior portal vein embolization. Liver volumes were measured by computed tomography volumetry before portal vein embolization, before liver resection, and 3 months after liver resection. Liver function was assessed by hepatobiliary scintigraphy before and 3 months after liver resection. RESULTS: Ten patients were included in the embolization group and 13 in the control group. Groups were comparable for gender, age, and number of patients with a compromised liver. The mean future remnant liver volume was 33.0 +/- 8.0% prior to portal vein embolization in the embolization group and 45.6 +/- 9.1% in the control group (p < 0.01). Prior to surgery, there were no significant differences in future remnant liver volume and function between the groups. Three months postoperatively, the mean remnant liver volume was 81.9 +/- 8.9% of the initial total liver volume in the embolization group and 79.4 +/- 11.0% in the control group (p > 0.05). Remnant liver function increased up to 88.1 +/- 17.4% and 83.3 +/- 14% respectively of the original total liver function (p > 0.05). CONCLUSION: Preoperative portal vein embolization does not negatively influence postoperative liver regeneration assessed 3 months after major liver resection.

Describing peripancreatic collections in severe acute pancreatitis using morphologic terms: an international interobserver agreement study.

BACKGROUND/AIMS: The current terminology for describing peripancreatic collections in acute pancreatitis (AP) derived from the Atlanta Symposium (e.g. pseudocyst, pancreatic abscess) has shown a very poor interobserver agreement, creating the potential for patient mismanagement. A study was undertaken to determine the interobserver agreement for a new set of morphologic terms to describe peripancreatic collections in AP. METHODS: An international, interobserver agreement study was performed: 7 gastrointestinal surgeons, 2 gastroenterologists and 8 radiologists in 3 US and 5 European tertiary referral hospitals independently evaluated 55 computed tomography (CT) scans of patients with predicted severe AP. The percentage agreement [median, interquartile range (IQR)] for 9 clinically relevant morphologic terms was calculated among all reviewers, and separately among radiologists and clinicians. The percentage agreement was defined as poor (<0.50), moderate (0.51-0.70), good (0.71-0.90), and excellent (0.91-1.00). RESULTS: Overall agreement was good to excellent for the terms collection (percentage agreement = 1; IQR 0.68-1), relation with pancreas (1; 0.68-1), content (0.88; 0.87-1), shape (1; 0.78-1), mass effect (0.78; 0.62-1), loculated gas bubbles (1; 1-1), and air-fluid levels (1; 1-1). Overall agreement was moderate for extent of pancreatic nonenhancement (0.60; 0.46-0.88) and encapsulation (0.56; 0.48-0.69). The percentage agreement was greater among radiologists than clinicians for extent of pancreatic nonenhancement (0.75 vs. 0.57, p = 0.008), encapsulation (0.67 vs. 0.46, p = 0.001), and content (1 vs. 0.78, p = 0.008). CONCLUSION: Interobserver agreement for the new set of morphologic terms to describe peripancreatic collections in AP is good to excellent. Therefore, we recommend that current clinically based definitions for CT findings in AP (e.g. pancreatic abscess) should no longer be used.

Controversies in the use of portal vein embolization.

BACKGROUND/AIMS: Portal vein embolization (PVE) has reached worldwide acceptance to increase future remnant liver (FRL) volume before undertaking major liver resection. The aim of this overview is to point out and discuss current controversies in the application of PVE. METHODS: Review of literature pertaining to techniques of PVE, complications, tumor proliferation, timing of resection, and hypertrophy response after PVE. RESULTS: Procedure-related complications after PVE include hematoma, hemobilia, overflow of embolization material, and thrombosis of portal vein branch(es) of the non-embolized lobe. Persistence of the embolized, atrophic lobe is usually not harmful. Embolization of the portal branches to segment 4 in addition to embolization of the right portal trunk is controversial and is advised only in selected cases. It remains undecided whether embolization of the portal venous system is more effective in inducing hypertrophy of the FRL than ligation of the portal vein. Accelerated tumor growth after PVE is a major concern and requires consideration of post-PVE chemotherapy. A waiting time of 3 weeks between PVE and liver resection is advised. Post-hepatectomy regeneration is not hampered after preoperative PVE. CONCLUSION: PVE is a useful preoperative intervention to increase volume and function of the FRL. Further progress awaits clarification of the mechanisms of the hypertrophy response induced by PVE in conjunction with new embolization materials and protective chemotherapy.