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In recent years, concern has grown about the inappropriate application and interpretation of P values, especially the use of P<0.05 to denote "statistical significance" and the practice of P-hacking to produce results below this threshold and selectively reporting these in publications. Such behavior is said to be a major contributor to the large number of false and non-reproducible discoveries found in academic journals. In response, it has been proposed that the threshold for statistical significance be changed from 0.05 to 0.005. The aim of the current study was to use an evolutionary agent-based model comprised of researchers who test hypotheses and strive to increase their publication rates in order to explore the impact of a 0.005 P value threshold on P-hacking and published false positive rates. Three scenarios were examined, one in which researchers tested a single hypothesis, one in which they tested multiple hypotheses using a P<0.05 threshold, and one in which they tested multiple hypotheses using a P<0.005 threshold. Effects sizes were varied across models and output assessed in terms of researcher effort, number of hypotheses tested and number of publications, and the published false positive rate. The results supported the view that a more stringent P value threshold can serve to reduce the rate of published false positive results. Researchers still engaged in P-hacking with the new threshold, but the effort they expended increased substantially and their overall productivity was reduced, resulting in a decline in the published false positive rate. Compared to other proposed interventions to improve the academic publishing system, changing the P value threshold has the advantage of being relatively easy to implement and could be monitored and enforced with minimal effort by journal editors and peer reviewers., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Fitzpatrick et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Iatrogenic ureteral injuries are a dramatic complication in medical practice. Nowadays there are no universal guidelines for their management. The aim of our study was to evaluate the feasibility of the percutaneous treatment in restoring ureteral integrity in 19 patients that came to our attention. In each case retrograde stenting failed and patients were candidates for re-surgery. Our strategy consists of two phases. The first step is the nephrostomy that allows an external urinary diversion putting dry the damaged ureteral segment. The second step is the anterograde ureteral double-J stenting that keeps near the two stumps promoting the healing of the injured tract. In complete sections, when both retrograde and anterograde stenting singularly failed, we performed a rendez-vous technique with a combined radiological trans-nephrostomic access and urological cystoscopic approach to realign and catheterize the ureteral stumps. In patients with Bricker urinary diversion, peri-anastomotic leaks were treated by positioning a multi-hole pig-tail catheter with the inner end in the renal pelvis and the distal portion outgoing from the cutaneous stoma. Subsequent pyelographic controls demonstrated the resolution of the ureteral leak in all patients and none required a surgical re-intervention. Nephrostomies were removed and ureteral stents were regularly changed. We conclude that interventional uro-radiology may offer a valid conservative option in iatrogenic urinary injuries.

Introduction: Hemobilia represents only 6% of all causes of upper gastrointestinal bleeding., Presentation of Case: We report a rare case of a bleeding pseudoaneurysm of the cystic artery, due to a re-activation of a chronic cholecystitis, which arose with a mixed symptomatology: jaundices and hematemesis., Discussion: The rarity of our patient is increased for some vascular anatomic variations detected by Computed Tomography that influenced the management of the disease. Our patient was treated by endovascular embolization of the pseudoaneurysm and subsequent cholecystectomy., Conclusion: About pseudoaneurysm of the cystic artery only few cases have been already reported and to date there are no guidelines for its management. We describe both diagnostic features and therapeutic strategies in comparison to the most recent literature., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Extragastrointestinal stromal tumors (EGISTs) are a rare subgroup of gastrointestinal stromal tumors (GISTs), arising from outside the walls of gastrointestinal tubular organs. We report a case of an EGIST of the lesser omentum that represented a diagnostic challenge. Due to its atypical radiologic findings, it was preoperatively mistaken for pedunculated hepatic hemangioma. Histopathologically, it showed epithelioid structure and c-kit negative, very uncommon for GIST. Only a few cases of EGISTs have been previously reported. We discuss imaging and histological features, emphasizing potential pitfalls., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Introduction. Congenital portosystemic venous malformations are rare abnormalities in which the portal blood drains into a systemic vein and which are characterized by extreme clinical variability. Case Presentations. The authors present two case reports of a congenital extrahepatic portosystemic shunt (Type II). In the first patient, apparently nonspecific symptoms, such as headache and fatigue, proved to be secondary to hypoglycemic episodes related to the presence of a portosystemic shunt, later confirmed on imaging. During portal vein angiography, endovascular embolization of the portocaval fistula achieved occlusion of the anomalous venous tract. In the second patient, affected by Down's syndrome, the diagnosis of a portosystemic malformation was made by routine ultrasonography, performed to rule out concurrent congenital anomalies. Because of the absence of symptoms, we chose to observe this patient. Conclusions. These two case reports demonstrate the clinical heterogeneity of this malformation and the need for a multidisciplinary approach. As part of a proper workup, clinical evaluation must always be followed by radiographic diagnosis.

Intraductal papillary mucinous neoplasms (IPMNs) represent a group of cystic pancreatic neoplasms with large range of clinical behaviours, ranging from low-grade dysplasia or borderline lesions to invasive carcinomas. They can be grouped into lesions originating from the main pancreatic duct, main duct IPMNs (MD-IPMNs), and lesions which arise from secondary branches of parenchyma, denominated branch-duct IPMNs (BD-IPMNs). Management of these cystic lesions is essentially based on clinical and radiological features. The latter have been very well described in the last fifteen years, with many studies published in literature showing the main radiological features of IPMNs. Currently, the goal of imaging modalities is to identify "high-risk stigmata" or "worrisome feature" in the evaluation of pancreatic cysts. Marked dilatation of the main duct (>1 cm), large size (3-5 cm), and intramural nodules have been associated with increased risk of degeneration. BD-IPMNs could be observed as microcystic or macrocystic in appearance, with or without communication with main duct. Their imaging features are frequently overlapped with cystic neoplasms. The risk of progression for secondary IPMNs is lower, and subsequently an imaging based follow-up is very often proposed for these lesions.

The incidence of cystic pancreatic neoplasms increased in the past decade, due to the recent advances in multidetector computed tomography and magnetic resonance imaging; several pancreatic cysts are incidentally encountered during diagnostic exams performed for non-pancreatic diseases. Indeed, cystic pancreatic tumors are currently considered relatively rare, accounting for approximately 10% of all pancreatic neoplasms. Serous cystadenoma, mucinous cystadenoma, intraductal papillary mucinous neoplasms and solid-pseudopapillary tumor represent about 90% of all pancreatic primary cystic tumours. The non-optimal diagnostic preoperative accuracy in distinguishing benign from malignant cystic lesions ensures that up till now there are no well-defined guidelines regarding the management of cystic pancreatic neoplasms. Imaging findings often do not allow the diagnosis, because there is a considerable overlap among the cystic lesions; the best pre-operative characterization is obtained by the association of all diagnostic procedures available. For their different histology and behavior, cystic pancreatic neoplasms need to be managed according to various factors. In this review, the main elements necessary for their management are assessed--radiological features, tumour dimensions, patients' characteristics, the mode of clinical presentation and the associated oncologic markers. A multidisciplinary approach--including gastroenterologists, radiologists and surgeons--should be adopted in order to perform a differential diagnosis and a correct management.

Material of Study: We report a case of a 66-year-old man with a gastric schwannoma incidentally discovered during the treatment of a colon cancer. At the pre-operative computed tomography performed for the stadiation of the colonic tumor was incidentally noted the presence of a nodular tumor between the liver and the gastric wall., Result: A wedge resection of this gastic tumor and the surgical resection of the left colon were performed all at once. The pathological examination of the gastric neoplasia revealed a picture consistent with gastric schwannoma., Discussion: Gastrointestinal schwannomas are difficult but not impossible to diagnose preoperatively although they are often asymptomatic and radiologic findings are often nonspecific. Radiological features of Gastrointestinal schwannomas described in literature are reviewed., Conclusions: The treatment of choice is complete surgical excision with free margins because of diagnostic uncertainty, and the long-term outcome is excellent as these lesions are uniformly benign.