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We report selected results of laboratory measurements and beam tests of heavily irradiated microstrip silicon detectors. The detectors were single-sided devices, produced by different manufacturers and irradiated with different sources, for several total ionizing doses and fluences up to 4 x [10.sup.14] 1-MeV-equivalent neutrons per [cm.sup.2]. Strip resistance and capacitance, detector leakage currents and breakdown performance were measured before and after irradiations. Signal-to-noise ratio and detector efficiency were studied in beam tests, for different values of the detector temperature and of the read-out pitch, as a function of the detector bias voltage. The goal of these test is to optimise the design of the final prototypes for the Silicon Strip Tracker of the CMS experiment at the CERN LHC collider.

Background and Aims: Despite the significant morbidity associated with gastric variceal bleeding, there is a paucity of high-quality data regarding optimal management. EUS-guided coil injection therapy (EUS-COIL) has recently emerged as a promising endoscopic modality for the treatment of gastric varices (GV), particularly compared with traditional direct endoscopic glue injection. Although there are data on the feasibility and safety of EUS-COIL in the management of GV, these have been limited to select centers with particular expertise. The aim of this study was to report the first U.S. multicenter experience of EUS-COIL for the management of GV., Methods: This retrospective analysis included patients with bleeding GV or GV at risk of bleeding who underwent EUS-COIL at 10 U.S. tertiary care centers between 2018 and 2022. Baseline patient and procedure-related information was obtained. EUS-COIL entailed the injection of .018 inch or .035 inch hemostatic coils using a 22-gauge or 19-gauge FNA needle. Primary outcomes were technical success (defined as successful deployment of coil into varix under EUS guidance with diminution of Doppler flow), clinical success (defined as cessation of bleeding if present and/or absence of bleeding at 30 days' postintervention), and intraprocedural and postprocedural adverse events., Results: A total of 106 patients were included (mean age 60.4 ± 12.8 years; 41.5% female). The most common etiology of GV was cirrhosis (71.7%), with alcohol being the most common cause (43.4%). Overall, 71.7% presented with acute GV bleeding requiring intensive care unit stay and/or blood transfusion. The most common GV encountered were isolated GV type 1 (60.4%). A mean of 3.8 ± 3 coils were injected with a total mean length of 44.7 ± 46.1 cm. Adjunctive glue or absorbable gelatin sponge was injected in 82% of patients. Technical success and clinical success were 100% and 88.7%, respectively. Intraprocedural adverse events (pulmonary embolism and GV bleeding from FNA needle access) occurred in 2 patients (1.8%), and postprocedural adverse events occurred in 5 (4.7%), of which 3 were mild. Recurrent bleeding was observed in 15 patients (14.1%) at a mean of 32 days. Eighty percent of patients with recurrent bleeding were successfully re-treated with repeat EUS-COIL. No significant differences were observed in outcomes between high-volume (>15 cases) and low-volume (<7 cases) centers., Conclusions: This U.S. multicenter experience on EUS-COIL for GV confirms high technical and clinical success with low adverse events. No significant differences were seen between high- and low-volume centers. Repeat EUS-COIL seems to be an effective rescue option for patients with recurrent bleeding GV. Further prospective studies should compare this modality versus other interventions commonly used for GV., Competing Interests: Disclosure The following authors disclosed financial relationships: M. Arain: Consultant for Olympus, Boston Scientific, and Cook. K. K. K. Baig: Grant recipient from Olympus; and consultant for Ambu. A. Schulman: Consultant for Apollo Endosurgery, Boston Scientific, Olympus, and Microtech; and grant/research funding from GI Dynamics and Fractyl. V. Kushnir: Consultant for Boston Scientific, Olympus, Medtronic, and Noah Medical. J. Shah: Consultant for Boston Scientific and Olympus. All other authors disclosed no financial relationships., (Copyright © 2024 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Management of acute pancreatitis is challenging in the presence of local complications that include pancreatic and peripancreatic collections and vascular complications. This review, targeted for interventional radiologists, describes minimally invasive endoscopic, image-guided percutaneous, and surgical procedures for management of complicated pancreatitis and provides insight into the procedures' algorithmic application. Local complications are optimally managed in a multidisciplinary team setting that includes advanced endoscopists; pancreatic surgeons; diagnostic and interventional radiologists; and specialists in infectious disease, nutrition, and critical care medicine. Large symptomatic or complicated sterile collections and secondary infected collections warrant drainage or débridement. The drainage is usually delayed for 4-6 weeks unless clinical deterioration warrants early intervention. If collections are accessible by endoscopy, endoscopic procedures are preferred to avoid pancreaticocutaneous fistulas. Image-guided percutaneous drainage is indicated for symptomatic collections that are not accessible for endoscopic drainage or that present in the acute setting before developing a mature wall. Peripancreatic arterial pseudoaneurysms should be embolized before necrosectomy procedures to prevent potentially life-threatening hemorrhage. Surgical procedures are reserved for symptomatic collections that persist despite endoscopic or interventional drainage attempts. Understanding these procedures facilitates their integration by interventional radiologists into the complex longitudinal care of patients with complicated pancreatitis.

Background/objectives: Severity classification systems of acute pancreatitis (AP) assess inpatient morbidity and mortality without predicting outpatient course of AP. To provide appropriate outpatient care, determinants of long-term prognosis must also be identified. The aim of this study was to define clinical groups that carry long-term prognostic significance in AP., Methods: A retrospective study that included patients admitted with AP was conducted. Determinants of long-term prognosis were extracted: These included Revised Atlanta and Determinant Based Classification (RAC), Charlson Comorbidity Index (CCI), Modified CT Severity Index (MCTSI), etiology, and local complications (LCs). Seven surrogates of morbidity up to 1 year after discharge were also collected and subsequently imputed into a clustering algorithm. The algorithm was set to produce three categories and multinomial regression analysis was performed., Results: 281 patients were included. The incidences of morbidity endpoints were similar among the 3 RAC categories. Three clusters were identified that carried long-term prognostic significance. Each cluster was given a name to reflect prognosis. The limited AP had the best prognosis and included patients without LCs with a low co-morbidity burden. The brittle AP had a low co-morbidity burden and high MCTSI (LCs 94%). It ran a very morbid course but had excellent survival. The high-risk AP had the worst prognosis with the highest mortality rate (28%). They had a high co-morbidity burden without local complications., Conclusion: Categories that carry long-term prognostic significance in AP have been developed. This study could help formulate appropriate follow-up and ultimately improve AP outcomes., (Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Objectives: Endoscopic drainage of complex hilar tumors has generally resulted in poor outcomes. Drainage of >50% of liver volume has been proposed as optimal, but not evaluated using long multifenestrated plastic stents (MFPS) or self-expanding metal stents (SEMS). We evaluated outcomes of endoscopic drainage of malignant hilar strictures using optimal strategy and stents, and determined factors associated with stent patency, survival, and complications., Methods: Cross-sectional study was conducted at an academic center over 5 years. MFPS (10 French or 8.5 French) or open-cell SEMS were used for palliation of unresectable malignant hilar strictures, with imaging-targeted drainage of as many sectors as needed to drain >50% of viable liver volume. Risk factors were evaluated using regression analysis. The cumulative risk was assessed using Kaplan-Meier analysis., Results: 77 patients with malignant hilar biliary strictures (median Bismuth IV) underwent targeted stenting (41 MFPS and 36 SEMS). Comparing MFPS vs. SEMS, technical success (95.1 vs. 97.2%, P=0.64), clinical success (75.6 vs. 83.3%, P=0.40), frequency of multiple stents (23/41 vs. 25/36, P=0.19), survival and adverse events were similar, but stent patency was significantly shorter (P<0.0001). Factors associated with survival were Karnofsky score and serum bilirubin level at presentation. Outcomes were independent of Bismuth class with acceptable results in Bismuth III and IV., Conclusions: Endoscopic biliary drainage with MFPS or open-cell SEMS targeting >50% of viable liver resulted in effective palliation in patients with complex malignant hilar biliary strictures. Patency was shorter in the MFPS group, but similar survival and complications were found when comparing MFPS and SEMS group.

Objectives: The aim of this study was to determine the association of visceral adiposity with severe outcomes in acute pancreatitis (AP)., Methods: This retrospective study included consecutive patients with AP admitted to a tertiary care hospital between January 2010 and January 2015 who underwent a computed tomography scan. The visceral adipose tissue (VAT) volume was estimated using the method of Linder and colleagues. Multivariable logistic regression analysis was conducted to assess VAT as a predictor of severe AP compared with other validated predictors of severity., Results: Five hundred and seventy four patients were admitted during the study period, of which 252 had a computed tomography scan available. Patients with severe AP had a larger VAT area compared with those with mild or moderate AP (mean: 184.9 cm vs 79.9 cm, P = 0.006). Patients who developed multisystem organ failure or had acute necrotic collections had a larger VAT area than those who did not (150.6 cm vs 91.0 cm, P = 0.004 and 174.0 cm vs 91.9 cm, P = 0.003, respectively). Visceral adipose tissue area demonstrated superior discrimination of severe AP compared with other severity predictors., Conclusions: Increased VAT area is a strong predictor of severe pancreatitis, necrosis, and multisystem organ failure.

Background: Interventions for necrotizing pancreatitis have undergone a recent paradigm shift toward minimally invasive techniques, including endoscopic transluminal necrosectomy (ETN). The optimal stent for endoscopic transmural drainage remains unsettled., Objective: To evaluate a novel large-bore, fully covered metal through-the-scope (TTS) esophageal stent for cystenterostomy in large walled-off necrosis (WON)., Design: Retrospective case series., Setting: Single tertiary care academic center., Patients: Ten patients with large (>10 cm) WON collections who underwent endoscopic transmural drainage and ETN., Intervention: Initial cystenterostomy was performed by using EUS, and in the same session, a TTS (18 × 60 mm), fully covered esophageal stent was placed to create a wide-bore fistula into the cavity. In 1 or more later sessions, the stent was removed, and ETN was performed as needed., Main Outcome Measurements: Technical and clinical success rates and adverse events., Results: The TTS stent was successfully deployed at the initial cystogastrostomy in all 10 patients. All patients had large WON (median size 17 cm, range 11-30 cm) and underwent intervention at a median of 30 days (range 12-117 days) after onset of acute pancreatitis. Resolution of WON was achieved in 9 of the 10 patients (90%) after a median of 3 endoscopic sessions. There were no early adverse events. Late adverse events occurred in 3 patients (30%); worsening of infection from stent migration and occlusion of cystogastrostomy (2 patients), and fatal pseudoaneurysmal bleeding from erosion of infected necrosis into a major artery distant from the stent (1 patient). The stent was easily removed in all the cases after resolution or improvement of the necrotic cavity., Limitations: Retrospective, single-center evaluation of a small number of cases. No comparative arm to determine the relative efficacy or cost-effectiveness of these stents compared with conventional plastic stents., Conclusions: Endoscopic therapy using a large-bore TTS, fully covered esophageal stent is feasible for use in the treatment of large WON. Further studies are needed to validate these findings., (Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)

Concern remains regarding the possibly higher risk to living liver donors of the right lobe (RL), as compared with the left lateral segment (LLS). We studied outcomes and responses to quality of life (QOL) surveys in the two groups. From 1997 to 2004, we performed 49 living donor liver transplants (LDLTs): 33 RL and 16 LLS. Notable differences included a higher proportion of female and unrelated donors in the RL group. A significantly larger liver mass was resected in RL (vs. LLS) donors: 720 (vs. 310) g, p = 0.01; RL donors also had greater blood loss (398 vs. 240 mL, p = 0.04) and operative times (7.2 vs. 5.7 h, p = 0.05). However, those findings did not translate into significant differences in donor morbidity. The complication rate was 12.5% in LLS donors and 9.1% in RL donors (p = ns). Per a QOL survey at 6 months postdonation, no significant differences were noted in SF-12 scores for the two groups. Recovery times were somewhat longer for RL donors. Mean time off work was 61.0 days for RL donors and 32.4 days for LLS donors (p = 0.004). RL donation is associated with greater operative stress for donors, but not necessarily with a more complicated recovery or differences in QOL.

Concern exists that partial liver transplants (either a living donor [LD] or deceased donor [DD] in hepatitis C virus (HCV)-positive recipients may be associated with an increased risk for recurrence. From 1999 to 2003, at our institution, 51 HCV-positive recipients underwent liver transplants: 32 whole-liver (WL) transplants, 12 LD transplants and 7 DD split transplants. Donor characteristics differed in that WL donors were older, and LD livers had lower ischemic times. Recipient characteristics were similar except that mean MELD scores in LD recipients were lower (p < 0.05). With a mean follow-up of 28.3 months, 46 (90%) recipients are alive: three died from HCV recurrent liver disease and two from tumor recurrence. Based on 1-year protocol biopsies, the incidence of histologic recurrence in the three groups is as follows: WL, 81%; LD, 50% and DD split, 86% (p = 0.06 for LD versus WL). The mean grade of inflammation on the biopsy specimens was: WL, 1.31; LD, 0.33 and DD split, 1.2 (p = 0.002 for LD versus WL; p = 0.03 for LD versus DD split). Mean stage of fibrosis was: WL, 0.96; LD, 0.22 and DD split, 0.60 (p = 0.07 for LD versus WL). Liver regeneration does not seem to affect hepatitis C recurrence as much, perhaps, as factors such as DD status, donor age and cold ischemic time.

On August 21, 1999, Region 7 of the United Network for Organ Sharing (UNOS) adopted a policy of regionwide sharing of cadaver livers for UNOS Status 1 recipients. We examined what impact this policy had at our center on their waiting times, waiting list mortality, and outcomes. From January 1, 1995, through December 31, 2002, our center listed 39 patients for an emergent (Status 1) transplant, according to the current criteria for Status 1 listing: patients (adult and pediatric) with fulminant hepatic failure (FHF), hepatic artery thrombosis, or primary nonfunction early after a liver transplant, or critically ill pediatric patients with chronic liver disease. These 39 candidates were analyzed in 2 groups: those listed before regionwide sharing (Group I, n = 19) and those listed after (Group II, n = 20). Patient characteristics did not differ significantly between the 2 groups, including mean donor and recipient age, proportion of pediatric patients, and type of graft used (i.e., living or deceased donor, segmental or whole-organ). FHF was the most common cause of liver failure in both groups-74% versus 70% (P = ns). The next most common cause in both groups was hepatic artery thrombosis, followed by primary nonfunction. Most transplants used deceased donors; however, 2 of the transplants in Group I versus only 1 in Group II used living donors. Waiting list mortality (the patient death rate before a transplant could take place) was 32% in Group I versus only 5% in Group II (P =.03). The mean number of days on the waiting list was also substantially lower in Group II (2.9 days) than in Group I, (5.8 days) (P =.04). For patients who underwent a transplant, graft and patient survival rates at 6 months posttransplant were 69.2% in Group I versus 89.5% in Group II (P =.03). In conclusion, the introduction of regionwide sharing seems to have been of benefit for Status 1 patients at our center. They have a significantly lower risk of dying while waiting for a transplant and undergo one in a much shorter period of time.

As the number of living donor (LD) and deceased donor (DD) split-liver transplants (SLTs) have increased over the last 5 years, so too has the interest in liver regeneration after such partial-liver transplants. We looked at liver regeneration, as measured by computed tomography (CT) volumetrics, to see if there were significant differences among LDs, right-lobe LD recipients, and SLT recipients. We measured liver volume at 3 months postoperatively by using CT, and we compared the result to the patient's ideal liver volume (ILV), which was calculated using a standard equation. The study group consisted of 70 adult patients who either had donated their right lobe for LD transplants (n = 24) or had undergone a partial-liver transplant (right-lobe LD transplants, n = 24; right-lobe SLTs, n = 11; left-lobe SLTs, n = 11). DD (vs. LDs) were younger (P < 0.01), were heavier (P = 0.06), and had longer ischemic times (P < 0.01). At 3 months postoperatively, LDs had attained 78.6% of their ILV, less than the percentage for right-lobe LD recipients (103.9%; P = 0.0002), right-lobe SLT recipients (113.6%; P = 0.01), and left-lobe SLT recipients (119.7%; P = 0.0006). When liver size at the third postoperative month was compared with the liver size immediately postoperatively, LDs had a 1.85-fold increase. This was smaller than the increase seen in right-lobe LD recipients (2.08-fold), right-lobe SLT recipients (2.17-fold), and left-lobe SLT recipients (2.52-fold). In conclusion, liver regeneration, as measured by CT volume, seems to be greatest in SLT recipients. LD recipients seem to have greater liver growth than their donors. The reason for this remains unclear.

Split-liver transplantation is becoming a useful technique to expand the donor pool. Whether the split should be performed in situ or ex situ is not clear. One potential disadvantage of in situ splits is that prolonged surgical time and increased blood loss may negatively affect the function of other solid organs (kidneys, pancreas, and heart) procured from the same donor. Therefore, we studied the function of other organs posttransplantation. Between September 1, 1999, and March 31, 2000, we performed six in situ splits at the University of Minnesota (Minneapolis, MN). These six splits yielded six right-lobe liver grafts and six left-lobe liver grafts, which were transplanted into 12 adult-size recipients. Other grafts obtained from these six donors were as follows: kidney (n = 11), heart (n = 4), lungs (n = 1), pancreas (n = 2), and kidney-pancreas (n = 1). We then analyzed posttransplantation function of these grafts and the postoperative course of transplant recipients. All six donors were hemodynamically stable at the time of procurement. Mean donor age was 19.7 years. Mean surgical time for the procurement was 7.4 hours, with an average blood loss of 490 mL during in situ splitting of the liver. The 12 liver grafts showed good initial function with no primary nonfunction. The other organs also showed good function. Of 11 kidney recipients, only 1 patient developed delayed graft function, which resolved within 4 days. In addition, 1 kidney was lost early because of severe acute rejection. For the 10 recipients with functioning kidneys, mean creatinine level at hospital discharge was 2.0 mg/dL, and mean creatinine level after an average 9-month follow-up was 1.3 mg/dL. Of the 4 heart transplant recipients, 3 patients had good graft function immediately posttransplantation, with an ejection fraction greater than 60%, minimal inotropic requirements, and no surgical complications. The fourth heart transplant recipient, a critically ill status 1 patient, had poor initial function and a prolonged intensive care unit stay. At hospital discharge, pancreas and pancreas-kidney transplant recipients were all insulin free, with good urine amylase levels, no surgical or infectious complications, and no evidence of significant pancreatitis posttransplantation. The kidney of the pancreas-kidney transplant recipient functioned immediately; creatinine level after 7 months of follow-up was 1.2 mg/dL. Despite increased surgical time and blood loss, in situ splitting of liver grafts can be accomplished in stable donors without significant negative effects on other organs.