279 research outputs found

    Diagnostic performance of preoperative CT in differentiating between benign and malignant origin of suspicious gallbladder lesions

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    Purpose: To determine diagnostic performance of preoperative CT in differentiating between benign and malignant suspicious gallbladder lesions and to develop a preoperative risk score. Method: All patients referred between January 2007 and September 2018 for suspicion of gallbladder cancer (GBC) or incidentally found GBC were retrospectively analyzed. Patients were excluded when preoperative CT or histopathologic examination was lacking. Two radiologists, blinded to histopathology results, independently reviewed CT images to differentiate benign disease from GBC. Multivariable analysis and internal validation were used to develop a risk score for GBC. Model discrimination, calibration, and diagnostic performance were assessed. Results: In total, 118 patients with 39 malignant (33 %) and 79 benign (67 %) lesions were included. Sensitivity of CT for diagnosing GBC was 90 % (95 % confidence interval [CI]: 76?97). Specificity rates were 61 % (95 % CI: 49?72) and 59 % (95 % CI: 48?70). Three predictors of GBC (irregular lesion aspect, absence of fat stranding, and locoregional lymphadenopathy) were included in the risk score ranging from -1 to 4. Adequate performance was found (AUC: 0.79, calibration slope: 0.89). In patients allocated >0 points, the model showed higher performance in excluding GBC than the radiologists (sensitivity 92 % [95 % CI: 79?98]). Moreover, when allocated >3 points, the risk score was superior in diagnosing GBC (specificity 99 % [95 % CI: 93?100]). Conclusions: Sensitivity rates of CT for differentiation between benign and malignant gallbladder lesions are high, however specificity rates are relatively low. The proposed risk score may facilitate differentiation between benign and malignant suspicious gallbladder lesions

    Topical Imiquimod Treatment of High-grade Cervical Intraepithelial Neoplasia (TOPIC-3):A Nonrandomized Multicenter Study

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    Topical imiquimod could be an alternative, noninvasive, treatment modality for high-grade cervical intraepithelial neoplasia (CIN). However, evidence is limited, and there are no studies that compared treatment effectiveness and side effects of topical imiquimod cream to standard large loop excision of the transformation zone (LLETZ) treatment. A multi-center, nonrandomized controlled trial was performed among women with a histologic diagnosis of CIN 2/3. Women were treated with either vaginal imiquimod (6.25 mg 3 times weekly for 8 to 16 wk) or LLETZ according to their own preference. Successful treatment was defined as the absence of high-grade dysplasia at the first follow-up interval after treatment (at 20 wk for the imiquimod group and at 26 wk for the LLETZ group). Secondary outcome measures were high-risk human papillomavirus (hrHPV) clearance, side effects, and predictive factors for successful imiquimod treatment. Imiquimod treatment was successful in 60% of women who completed imiquimod treatment and 95% of women treated with LLETZ. hrHPV clearance occurred in 69% and 67% in the imiquimod group and LLETZ group, respectively. This study provides further evidence on topical imiquimod cream as a feasible and safe treatment modality for high-grade CIN. Although the effectiveness is considerably lower than LLETZ treatment, imiquimod treatment could prevent initial surgical treatment in over 40% of women and should be offered to a selected population of women who wish to avoid (repeated) surgical treatment of high-grade CIN

    Liver Volumetry Plug and Play: Do It Yourself with ImageJ

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    AB - BACKGROUND: A small remnant liver volume is an important risk factor for posthepatectomy liver failure and can be predicted accurately by computed tomography (CT) volumetry using radiologic image analysis software. Unfortunately, this software is expensive and usually requires support by a radiologist. ImageJ is a freely downloadable image analysis software package developed by the National Institute of Health (NIH) and brings liver volumetry to the surgeon's desktop. We aimed to assess the accuracy of ImageJ for hepatic CT volumetry. METHODS: ImageJ was downloaded from http://www.rsb.info.nih.gov/ij/ . Preoperative CT scans of 15 patients who underwent liver resection for colorectal cancer liver metastases were retrospectively analyzed. Scans were opened in ImageJ; and the liver, all metastases, and the intended parenchymal transection line were manually outlined on each slice. The area of each selected region, metastasis, resection specimen, and remnant liver was multiplied by the slice thickness to calculate volume. Volumes of virtual liver resection specimens measured with ImageJ were compared with specimen weights and calculated volumes obtained during pathology examination after resection. RESULTS: There was an excellent correlation between the volumes calculated with ImageJ and the actual measured weights of the resection specimens (r(2) = 0.98, p < 0.0001). The weight/volume ratio amounted to 0.88 +/- 0.04 (standard error) and was in agreement with our earlier findings using CT-linked radiologic software. CONCLUSION: ImageJ can be used for accurate hepatic CT volumetry on a personal computer. This application brings CT volumetry to the surgeon's desktop at no expense and is particularly useful in cases of tertiary referred patients, who already have a proper CT scan on CD-ROM from the referring institution. Most likely the discrepancy between volume and weight results from exsanguination of the liver after resectio

    Hypothermic Machine Perfusion in Liver Transplantation - A Randomized Trial

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    BACKGROUND Transplantation of livers obtained from donors after circulatory death is associated with an increased risk of nonanastomotic biliary strictures. Hypothermic oxygenated machine perfusion of livers may reduce the incidence of biliary complications, but data from prospective, controlled studies are limited. METHODS In this multicenter, controlled trial, we randomly assigned patients who were undergoing transplantation of a liver obtained from a donor after circulatory death to receive that liver either after hypothermic oxygenated machine perfusion (machine-perfusion group) or after conventional static cold storage alone (control group). The primary end point was the incidence of nonanastomotic biliary strictures within 6 months after transplantation. Secondary end points included other graft-related and general complications. RESULTS A total of 160 patients were enrolled, of whom 78 received a machine-perfused liver and 78 received a liver after static cold storage only (4 patients did not receive a liver in this trial). Nonanastomotic biliary strictures occurred in 6% of the patients in the machine-perfusion group and in 18% of those in the control group (risk ratio, 0.36; 95% confidence interval [CI], 0.14 to 0.94; P=0.03). Postreperfusion syndrome occurred in 12% of the recipients of a machine-perfused liver and in 27% of those in the control group (risk ratio, 0.43; 95% CI, 0.20 to 0.91). Early allograft dysfunction occurred in 26% of the machine-perfused livers, as compared with 40% of control livers (risk ratio, 0.61; 95% CI, 0.39 to 0.96). The cumulative number of treatments for nonanastomotic biliary strictures was lower by a factor of almost 4 after machine perfusion, as compared with control. The incidence of adverse events was similar in the two groups. CONCLUSIONS Hypothermic oxygenated machine perfusion led to a lower risk of nonanastomotic biliary strictures following the transplantation of livers obtained from donors after circulatory death than conventional static cold storage

    Exploring the drivers of global and local sea-level change over the 21st century and beyond

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    We present a new set of global and local sea-level projections at example tide gauge locations under the RCP2.6, RCP4.5 and RCP8.5 emissions scenarios. Compared to the CMIP5-based sealevel projections presented in IPCC AR5, we introduce a number of methodological innovations, including: (i) more comprehensive treatment of uncertainties; (ii) direct traceability between global and local projections; (iii) exploratory extended projections to 2300 based on emulation of individual CMIP5 models. Combining the projections with observed tide gauge records, we explore the contribution to total variance that arises from sea-level variability, different emissions scenarios and model uncertainty. For the period out to 2300 we further breakdown the model uncertainty by sea-level component and consider the dependence on geographic location, time horizon and emissions scenario. Our analysis highlights the importance of variability for sea-level change in the coming decades and the potential value of annual-to-decadal predictions of local sea-level change. Projections to 2300 show a substantial degree of committed sea-level rise under all emissions scenarios considered and highlights the reduced future risk associated with RCP2.6 and RCP4.5 compared to RCP8.5. Tide gauge locations can show large (> 50%) departures from the global average, in some cases even reversing the sign of the change. While uncertainty in projections of the future Antarctic ice dynamic response tends to dominate post2100, we see a substantial differences in the breakdown of model variance as a function of location, timescale and emissions scenario

    Effects of climate change on exposure to coastal flooding in Latin America and the Caribbean

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    This study considers and compares several of the most important factors contributing to coastal flooding in Latin American and the Caribbean (LAC) while accounting for the variations of these factors with location and time. The study assesses the populations, the land areas and the built capital exposed at present and at the middle and end of the 21st century for a set of scenarios that include both climatic and non-climatic drivers. Climatic drivers include global mean sea level, natural modes of climate variability such as El Niño, natural subsidence, and extreme sea levels resulting from the combination of projected local sea-level rise, storm surges and wave setup. Population is the only human-related driver accounted for in the future. Without adaptation, more than 4 million inhabitants will be exposed to flooding from relative sea-level rise by the end of the century, assuming the 8.5 W m&#8722;2 trajectory of the Representative Concentration Pathways (RCPs), or RCP8.5. However, the contributions from El Niño events substantially raise the threat in several Pacific-coast countries of the region and sooner than previously anticipated. At the tropical Pacific coastlines, the exposure by the mid-century for an event similar to El Niño 1998 would be comparable to that of the RCP4.5 relative sea-level rise by the end of the century. Furthermore, more than 7.5 million inhabitants, 42,600 km2 and built capital valued at 334 billion USD are currently situated at elevations below the 100-year extreme sea level. With sea levels rising and the population increasing, it is estimated that more than 9 million inhabitants will be exposed by the end of the century for either of the RCPs considered. The spatial distribution of exposure and the comparison of scenarios and timeframes can serve as a guide in future adaptation and risk reduction policies in the region

    Do we need to distance ourselves from the distance concept? Why home and host country context might matter more than (cultural) distance

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    We scrutinize the explanatory power of one of the key concepts in International Business: the concept of (cultural) distance. Here we focus on its effect on entry mode choice, one of the most researched fields in international business strategy. Our findings might, however, be equally be relevant for the field of International Business as a whole. Our analysis is based on a review of 92 prior studies on entry mode choice, as well as an empirical investigation in over 800 subsidiaries of MNCs, covering nine host and fifteen home countries across the world. We conclude that the explanatory power of distance is highly limited once home and host country context are accounted for, and that any significant effects of cultural distance on entry mode choice might simply be caused by inadequate sampling. Entry mode studies in particular, and International Business research in general, would do well to reconsider its fascination with distance measures, and instead, focus first and foremost on differences in home and host country context. We argue that serious engagement with deep contextualization is necessary in International Business research to pose new and relevant questions and develop new and innovative theories that explain empirical phenomena

    Effect of surgical volume on short-term outcomes of cytoreductive surgery for advanced-stage ovarian cancer:A population-based study from the Dutch Gynecological Oncology Audit

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    Objective: Despite lacking clinical data, the Dutch government is considering increasing the minimum annual surgical volume per center from twenty to fifty cytoreductive surgeries (CRS) for advanced-stage ovarian cancer (OC). This study aims to evaluate whether this increase is warranted. Methods: This population-based study included all CRS for FIGO-stage IIB-IVB OC registered in eighteen Dutch hospitals between 2019 and 2022. Short-term outcomes included result of CRS, length of stay, severe complications, 30-day mortality, time to adjuvant chemotherapy, and textbook outcome. Patients were stratified by annual volume: low-volume (nine hospitals, &lt;25), medium-volume (four hospitals, 29–37), and high-volume (five hospitals, 54–84). Descriptive statistics and multilevel logistic regressions were used to assess the (case-mix adjusted) associations of surgical volume and outcomes. Results: A total of 1646 interval CRS (iCRS) and 789 primary CRS (pCRS) were included. No associations were found between surgical volume and different outcomes in the iCRS cohort. In the pCRS cohort, high-volume was associated with increased complete CRS rates (aOR 1.9, 95%-CI 1.2–3.1, p = 0.010). Furthermore, high-volume was associated with increased severe complication rates (aOR 2.3, 1.1–4.6, 95%-CI 1.3–4.2, p = 0.022) and prolonged length of stay (aOR 2.3, 95%-CI 1.3–4.2, p = 0.005). 30-day mortality, time to adjuvant chemotherapy, and textbook outcome were not associated with surgical volume in the pCRS cohort. Subgroup analyses (FIGO-stage IIIC-IVB) showed similar results. Various case-mix factors significantly impacted outcomes, warranting case-mix adjustment. Conclusions: Our analyses do not support further centralization of iCRS for advanced-stage OC. High-volume was associated with higher complete pCRS, suggesting either a more accurate selection in these hospitals or a more aggressive approach. The higher completeness rates were at the expense of higher severe complications and prolonged admissions.</p
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