Risk-Adapted Anastomosis for Partial Pancreaticoduodenectomy Reduces the Risk of Pancreatic Fistula: A Pilot Study

Background

Pancreatic fistula (PF) is the main cause of postoperative morbidity and mortality after pancreatectomy. Two reasons for PF are a “soft” pancreatic texture and a narrow pancreatic duct (high-risk gland). Pancreaticojejunostomy (PJ) may lead to a higher fistula rate in such glands. In the literature there are no data available on risk-adapted assignment of pancreatogastrostomy (PG) in a high-risk gland. Therefore, an observational pilot study was conducted to address this issue.

Methods

Since January 2007 the concept of a “risk-adapted pancreatic anastomosis” (RAP) was introduced (PG for high-risk glands). The PF rate, morbidity, and mortality during this period (January 2007 to December 2008, n = 74) were compared to those between January 2004 and December 2006 (n = 119, only PJ). PF was defined according to the International Study Group on Pancreatic Surgery.

Results

Through RAP the PF rate was reduced from 22 to 11% (P = 0.0503). Grade C PF rate was reduced from 6.7 to 1.4% (P = 0.1569) and grade A PF from 6 to 1.4% (P = 0.2537). The PF-associated mortality was reduced from 3.4 to 1.4%. PG revealed a PF rate of 7% and PJ accounted for 19% of PFs (P = 0.1765). There was no incidence of grade C PF following PG. The incidence of intraluminal hemorrhage (P = 0.0422) and delayed gastric emptying (P = 0.0572) was higher following PG.

Conclusions

The rate of PF could be significantly reduced with the use of RAP. One should be cautious about the indication for PG, since it is associated with a higher rate of intraluminal hemorrhage and delayed gastric emptying. There are no long-term results on PG with respect to its durability and function. A general recommendation for its use cannot currently be made.     

Assessment and characterization of phenotypic heterogeneity of anxiety disorders across five large cohorts

To achieve sample sizes necessary for effectively conducting genome‐wide association studies (GWASs), researchers often combine data from samples possessing multiple potential sources of heterogeneity. This is particularly relevant for psychiatric disorders, where symptom self‐report, differing assessment instruments, and diagnostic comorbidity complicates the phenotypes and contribute to difficulties with detecting and replicating genetic association signals. We investigated sources of heterogeneity of anxiety disorders (ADs) across five large cohorts used in a GWAS meta‐analysis project using a dimensional structural modeling approach including confirmatory factor analyses (CFAs) and measurement invariance (MI) testing. CFA indicated a single‐factor model provided the best fit in each sample with the same pattern of factor loadings. MI testing indicated degrees of failure of metric and scalar invariance which depended on the inclusion of the effects of sex and age in the model. This is the first study to examine the phenotypic structure of psychiatric disorder phenotypes simultaneously across multiple, large cohorts used for GWAS. The analyses provide evidence for higher order invariance but possible break‐down at more detailed levels that can be subtly influenced by included covariates, suggesting caution when combining such data. These methods have significance for large‐scale collaborative studies that draw on multiple, potentially heterogeneous datasets. Copyright © 2016 John Wiley & Sons, Ltd.     

Magnetic resonance imaging for assessment of radiofrequency lesions in kidney tissue immediately after ablation: an experimental study

BACKGROUND AND PURPOSE: Radiofrequency ablation (RFA) is an attractive minimally invasive treatment option for small renal masses. The purpose of this study was to investigate the morphologic imaging appearance of RF lesions immediately after the ablation of kidney tissue using standard clinical MR sequences, as well as to investigate the correlation between MR and gross lesion size. MATERIALS AND METHODS: Ablations were performed 17 times in a standardized model of ex-vivo perfused porcine kidneys using a resistance-controlled RF device (250 W, 470 kHz) and a nonexpandable bipolar applicator inserted into the center of healthy renal parenchyma. The RF current was applied for 9 minutes at 20 W. Imaging was performed after ablation using standard clinical MR sequences: morphologic T(1)/T(2)- weighted images and an isotropic post-contrast T(1) high-resolution measurement (VIBE). Maximum lesion diameters were measured in three directions and were compared with the measurements of the gross lesions. Histologic (hematoxylin + eosin and nicotinamide adenine dinucleotide staining) and statistical analyses were performed. RESULTS: The gross pathologic examination showed a firm, white-yellow ablation zone sharply demarcated from the untreated tissue. The histologic examination confirmed cellular viability outside but not in the treatment zone. The RF lesions were hyperintense on T(1)-weighted images and hypointense on T(2)-weighted images. The lesion size measured in the VIBE images correlated best with the macroscopic lesion size (N = 16). CONCLUSIONS: Morphologic MR T(1) and T(2) sequences of RF lesions immediately after ablation produce reliable and consistent imaging characteristics. The post-contrast, high-resolution sequence (VIBE) enables the extent of the lesion to be determined accurately. The potential uses of this imaging strategy in clinical practise warrant further investigation on human renal-cell carcinoma.     

The effect of hydroxychloroquine on platelet activation in model experiments

Journal of Thrombosis and Thrombolysis - Hydroxychloroquine (HCQ) is an antimalarial agent with pleiotropic effects and now represents a cornerstone in the management of patients with autoimmune...