Gradient inflammation in the pancreatic stump after pancreaticoduodenectomy: Two case reports and review of literature.

BACKGROUND: Postoperative pancreatic fistula (POPF) contributes significantly to morbidity and mortality after pancreaticoduodenectomy (PD). However, the underlying mechanisms remain unclear. This study explored this pathology in the pancreatic stumps and elucidated the mechanisms of POPF following PD. CASE SUMMARY: Pathological analysis and 16S rRNA gene sequencing were performed on specimens obtained from two patients who underwent complete pancreatectomy for grade C POPF after PD. Gradient inflammation is present in the pancreatic stump. The apoptosis was lower than that in the normal pancreas. Moreover, neutrophil-dominated inflammatory cells are concentrated in the ductal system. Notably, neutrophils migrated through the ductal wall in acinar duct metaplasia-formed ducts. Additionally, evidence indicates that gut microbes migrate from the digestive tract. Gradient inflammation occurs in pancreatic stumps after PD. CONCLUSION: The mechanisms underlying POPF include high biochemical activity in the pancreas, mechanical injury, and digestive reflux. To prevent POPF and address pancreatic inflammation and reflux, breaking the link with anastomotic dehiscence is practical.

CT target scanning in the diagnosis of solid pseudopapillary tumor of the pancreas.

OBJECTIVE: To discuss the value of computed tomography (CT) iterative reconstruction technique combined with target scanning in the diagnosis of solid pseudopapillary tumor of the pancreas (SPTP). METHODS: The clinical information and CT examination data of 27 patients with SPTP were retrospectively analyzed, and the general condition and CT performance of the patients were observed. The CT image reconstruction algorithm of all patients used iterative reconstruction technique combined with the application of target scanning technique. RESULTS: A total of 27 patients were included in this study, including 6 males and 21 females, aged 14-72 years with a mean age of 39.6 ± 13.6 years. SPTP was more common in young and middle-aged females, with a low level of tumor markers, dominated by cystic-solid tumors. The combination of CT iterative reconstruction technology and targeted scanning revealed the following: the capsule of SPTP was clear and complete, where calcifications were visible, solid components were progressively enhanced, and rare pancreatic and bile duct dilation was seen. Tumors were cystic-solid in 18 of 27 patients with SPTP, of which the solid components showed isodensity or slightly low-density, with calcifications. The solid components and cyst walls were mildly enhanced during the arterial phase, and were progressively enhanced during the parenchymal phase, portal vein phase, and delayed phase, with their enhancement degree lower than that of normal pancreatic parenchyma, and pancreatic and bile duct dilation was rare. There were no statistical differences in tumor location, morphology, growth pattern, integrity of capsule, cystic or solid, calcifications, and enhancement features between the male group and the female group (P > 0.05). CONCLUSION: The iterative reconstruction combined with target scanning clearly displayed the CT features of tumors, helping the diagnosis and clinical treatment of the disease.

MRI-based radiomics approach for differentiation of hypovascular non-functional pancreatic neuroendocrine tumors and solid pseudopapillary neoplasms of the pancreas.

BACKGROUND: This study aims to investigate the value of radiomics parameters derived from contrast enhanced (CE) MRI in differentiation of hypovascular non-functional pancreatic neuroendocrine tumors (hypo-NF-pNETs) and solid pseudopapillary neoplasms of the pancreas (SPNs). METHODS: Fifty-seven SPN patients and twenty-two hypo-NF-pNET patients were enrolled. Radiomics features were extracted from T1WI, arterial, portal and delayed phase of MR images. The enrolled patients were divided into training cohort and validation cohort with the 7:3 ratio. We built four radiomics signatures for the four phases respectively and ROC analysis were used to select the best phase to discriminate SPNs from hypo-NF-pNETs. The chosen radiomics signature and clinical independent risk factors were integrated to construct a clinic-radiomics nomogram. RESULTS: SPNs occurred in younger age groups than hypo-NF-pNETs (P < 0.0001) and showed a clear preponderance in females (P = 0.0185). Age was a significant independent factor for the differentiation of SPNs and hypo-NF-pNETs revealed by logistic regression analysis. With AUC values above 0.900 in both training and validation cohort (0.978 [95% CI, 0.942-1.000] in the training set, 0.907 [95% CI, 0.765-1.000] in the validation set), the radiomics signature of the arterial phase was picked to build a clinic-radiomics nomogram. The nomogram, composed by age and radiomics signature of the arterial phase, showed sufficient performance for discriminating SPNs and hypo-NF-pNETs with AUC values of 0.965 (95% CI, 0.923-1.000) and 0.920 (95% CI, 0.796-1.000) in the training and validation cohorts, respectively. Delong Test did not demonstrate statistical significance between the AUC of the clinic-radiomics nomogram and radiomics signature of arterial phase. CONCLUSION: CE-MRI-based radiomics approach demonstrated great potential in the differentiation of hypo-NF-pNETs and SPNs.

110 Patients with adenosquamous carcinomas of the pancreas (PASC): imaging differentiation of small (≤ 3 cm) versus large (> 3 cm) tumors.

OBJECTIVE: This study examined radiological imaging features of small (≤ 3 cm) and large (> 3 cm) adenosquamous carcinomas of the pancreas (PASC) lesions to better understand the morphology of these lesions. METHODS: Images from 110 patients with pathologically proven PASC (80 males and 30 females, mean age: 62.6 years) were retrospectively reviewed. Two radiologists analyzed images and reached a consensus regarding the following features: location, shape, margins, presence of solid and necrotic components, rim enhancement, density/intensity during the portal venous phase, invasion of surrounding organs, vascular invasion, venous tumor thrombus formation, and enlarged lymph nodes. Differences in the imaging features between the two groups were evaluated with the Chi-square test or Fisher's exact test. RESULTS: There were 41 small PASC lesions (mean age: 60.59 years) and 69 large PASC lesions (63.74 years). Statistical analysis demonstrated significant differences in the location, shape, adjacent organ and vessel invasion, and venous tumor thrombus formation (P < 0.05). Small PASC lesions were more frequently detected in the pancreatic head and had an ovoid shape. There was no significant difference in the presence of solid and necrotic components (P = 0.090), including approximately 3/4 of the lesions with necrosis and 1/4 purely solid lesions, enlarged lymph nodes (P = 0.068) and other features. CONCLUSION: Regardless of the tumor size, 75% of PASC lesions present with central necrosis while 25% are purely solid. Small PASC lesions can be associated with lymph node metastasis at a relatively early stage. Large PASC lesions are likely to invade adjacent tissues and be associated with venous tumor thrombus formation.

Safety and Efficacy of a New Smartphone-controlled Vibrating Capsule on Defecation in Beagles.

Constipation, mainly manifesting as abdominal discomfort and painful defecation, is considered as a chronic disorder. Due to a lack of effective therapy, it imposes a significant economic burden and greatly impacts patients' quality of life which prompt searches for new, original approaches. Based on the research of vibrating capsule (VC) carried out by Ron et al., we investigated the safety and efficacy of an innovative, multi-mode VC in terms of its effect on defecation in animal studies. The parameters associated with different operation modes of VCs can be detected and adjusted by smartphone controlled external configuration device (ECD). The results of blood tests, physiological parameters, CT scan and pathological examination showed no significant abnormality, which undoubtedly confirmed the safety of VCs. For efficacy studies, defecation frequency of beagles increased after administration of these capsules without influence on stool characters. Meanwhile, the mean time of capsule evacuation tended to be reduced while showing no significant difference between different modes. In summary, this study elucidates the safety and effectiveness of VC in prompting the passage of gastrointestinal walls thus greatly increasing the defecation frequency. This study innovatively displays the promising application of VC in the treatment of constipation.

A temporary stent graft as a new shunt for juxtahepatic vena cava injury.

BACKGROUND: Juxtahepatic vena cava (JHC) injury is difficult to handle because of JHC injury's specific position and liver obstruction. The traditional shunt method initially appeared to be useful but ultimately failed. Simple and effective methods are needed to solve it. METHODS: Firstly, the clinical data, including the computed tomography images, of 120 patients were collected. In addition, a JHC digital model was constructed based on computed tomography images. According to the digital model data, a circulation loop simulating the blood flow in the JHC was established. Secondly, we analyzed the hemodynamics of a JHC shunt with pig blood. Finally, the new shunt was designed based on the data obtained. The shunt consists of a covered stent and transfer device and was tested. RESULTS: The JHC has a three-dimensional cylindrical structure. The mean (SD) length of the retrohepatic vena cava is 78.21 (9.83) mm, which shows correlations with the patient's age and weight (r = -0.343 and 0.271, respectively, p < 0.05). An equation is obtained as follows: retrohepatic vena cava (millimeter) = 71.23 - 0.293 × age (year) + 0.32 × weight (kilogram). The shunt diameters must be 10 mm and 12 mm to maintain the blood pressure difference Point a and Point b at approximately 3.75 mm Hg (5 cm H2O), when the flow rate is 3,000 mL/min and 5,000 mL/min, respectively. The stent graft showed effective hemostasis in tests. However, it failed when the inferior vena cava was pulled harder. CONCLUSION: A temporary stent graft as a new shunt for JHC injury has not been previously reported. It is a combination of both a traditional operation and a simple endovascular technique, which showed effective hemostasis in tests.