ABSTRACT
Backgrounds/Aims: Systematic investigations into the prognostic impact of the longitudinal tumor location in gallbladder cancer (GBC) remain insufficient. To address the limitations of our pilot study, we conducted a multicenter investigation to clarify the impact of the longitudinal tumor location on the oncological outcomes of GBC. Methods: A retrospective multicenter study was conducted on 372 patients undergoing radical resections for GBC from January 2010 to December 2019 across seven hospitals that belong to the Daejeon-Chungcheong branch of the Korean Association of Hepato-Biliary-Pancreatic Surgery. Patients were divided into GBC in the fundus/body (FB-GBC) and GBC in the neck/cystic duct (NC-GBC) groups, based on the longitudinal tumor location. Results: Of 372 patients, 282 had FB-GBC, while 90 had NC-GBC. NC-GBC was associated with more frequent elevation of preoperative carbohydrate antigen (CA) 19-9 levels, requirement for more extensive surgery, more advanced histologic grade and tumor stages, more frequent lymphovascular and perineural invasion, lower R0 resection rates, higher recurrence rates, and worse 5-year overall and disease-free survival rates. Propensity score matching analysis confirmed these findings, showing lower R0 resection rates, higher recurrence rates, and worse survival rates in the NC-GBC group. Multivariate analysis identified elevated preoperative CA 19-9 levels, lymph node metastasis, and non-R0 resection as independent prognostic factors, but not longitudinal tumor location. Conclusions: NC-GBC exhibits more frequent elevation of preoperative CA 19-9 levels, more advanced histologic grade and tumor stages, lower R0 resection rates, and poorer overall and disease-free survival rates, compared to FB-GBC. However, the longitudinal tumor location was not analyzed as an independent prognostic factor.
ABSTRACT
Spontaneously ruptured hepatocellular carcinoma (srHCC) is a life-threatening disease. The prognosis of patients with srHCC after hepatectomy remains unclear. This study aimed to investigate the prognosis and recurrence after hepatectomy in patients with srHCC. From 2015 to 2020, a retrospective analysis of patients with srHCC who underwent hepatectomy was performed, and compared with patients with unruptured HCC. Among the 86 patients with HCC who underwent hepatectomy, 11 had srHCC. The median tumor size in the ruptured group was significantly larger than that in the unruptured group (Pâ =â .001). The incidence rate of vascular invasion and Glisson capsule invasion in the ruptured group was significantly higher than that in the unruptured group. (Pâ =â .012 and Pâ <â .001, respectively). The American Joint Committee on Cancer was significantly higher in the ruptured group than in the unruptured group (Pâ <â .001). In total, 8 (73%) patients in the ruptured group experienced recurrence, whereas the median recurrence-free survival (RFS) and overall survival (OS) periods in the ruptured group were 15 (11-32) and 23 (17-38) months, respectively. In the unruptured group, 34 (45%) patients experienced recurrence, and the median RFS and OS periods were 20 (8-37, Pâ =â .099) and 33 (12-51, Pâ =â .394) months, respectively. Patients who developed peritoneal metastases were included in the ruptured group (nâ =â 3). Ruptured HCCs exhibit worse oncological outcomes have poorer survival and higher recurrence rates than unruptured HCCs.
Subject(s)
Carcinoma, Hepatocellular , Hepatectomy , Liver Neoplasms , Neoplasm Recurrence, Local , Humans , Liver Neoplasms/surgery , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/surgery , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Hepatectomy/methods , Male , Female , Middle Aged , Retrospective Studies , Neoplasm Recurrence, Local/epidemiology , Prognosis , Rupture, Spontaneous , Aged , AdultABSTRACT
We investigated the clinical implications of the mean corpuscular volume (MCV) in patients with major trauma. This single-center retrospective review included 2021 trauma patients admitted to the intensive care unit between January 2016 and June 2020. We included 1218 patients aged [Formula: see text] 18 years with an injury severity score [Formula: see text] 16 in the final analysis. The clinical and laboratory variables were compared between macrocytosis (defined as MCV [Formula: see text] 100 fL) and non-macrocytosis groups. Cox regression analysis was performed to calculate the hazard ratios (HRs) of variables for 30-day mortality, with adjustment for other potential confounding factors. The initial mean value of MCV was 102.7 fL in the macrocytosis group (n = 199) and 93.7 fL in the non-macrocytosis group (n = 1019). The macrocytosis group showed a significantly higher proportion of initial hypotension, transfusion within 4 and 24 h, and 30-day mortality than the non-macrocytosis group. Age ([Formula: see text] 65 years), hypotension (systolic blood pressure [Formula: see text] 90 mmHg), transfusion (within 4 h), anemia (Hb < 12 g/day in women, < 13 g/day in men), and macrocytosis were significantly associated with 30-day mortality (adjusted HR = 1.4; 95% confidence interval 1.01-1.94; p = 0.046) in major trauma patients. Thus, initial macrocytosis independently predicted 30-day mortality in patients with major trauma at a Level I trauma center.
Subject(s)
Anemia, Macrocytic , Anemia , Folic Acid Deficiency , Hypotension , Male , Humans , Female , Aged , Erythrocyte Indices , Retrospective Studies , PrognosisABSTRACT
Multi-agent systems are promising for applications in various fields. However, they require optimization algorithms that can handle large number of agents and heterogeneously connected networks in clustered environments. Planning algorithms performed in the decentralized communication model and clustered environment require precise knowledge about cluster information by compensating noise from other clusters. This article proposes a decentralized data aggregation algorithm using consensus method to perform COUNT and SUM aggregation in a clustered environment. The proposed algorithm introduces a trust value to perform accurate aggregation on cluster level. The correction parameter is used to adjust the accuracy of the solution and the computation time. The proposed algorithm is evaluated in simulations with large and sparse networks and small bandwidth. The results show that the proposed algorithm can achieve convergence on the aggregated data with reasonable accuracy and convergence time. In the future, the proposed tools will be useful for developing a robust decentralized task assignment algorithm in a heterogeneous multi-agent multi-task environment.
ABSTRACT
Acute kidney injury (AKI) is common in patients with trauma and is associated with poor outcomes. Therefore, early prediction of AKI in patients with trauma is important for risk stratification and the provision of optimal intensive care unit treatment. This study aimed to compare 2 models, machine learning (ML) techniques and logistic regression, in predicting AKI in patients with trauma. We retrospectively reviewed the charts of 400 patients who sustained torso injuries between January 2016 and June 2020. Patients were included if they were aged > 15 years, admitted to the intensive care unit, survived for > 48 hours, had thoracic and/or abdominal injuries, had no end-stage renal disease, and had no missing data. AKI was defined in accordance with the Kidney Disease Improving Global Outcomes definition and staging system. The patients were divided into 2 groups: AKI (n = 78) and non-AKI (n = 322). We divided the original dataset into a training (80%) and a test set (20%), and the logistic regression with stepwise selection and ML (decision tree with hyperparameter optimization using grid search and cross-validation) was used to build a model for predicting AKI. The models established using the training dataset were evaluated using a confusion matrix receiver operating characteristic curve with the test dataset. We included 400 patients with torso injury, of whom 78 (19.5%) progressed to AKI. Age, intestinal injury, cumulative fluid balance within 24 hours, and the use of vasopressors were independent risk factors for AKI in the logistic regression model. In the ML model, vasopressors were the most important feature, followed by cumulative fluid balance within 24 hours and packed red blood cell transfusion within 4 hours. The accuracy score showed no differences between the 2 groups; however, the recall and F1 score were significantly higher in the ML model (.94 vs 56 and.75 vs 64, respectively). The ML model performed better than the logistic regression model in predicting AKI in patients with trauma. ML techniques can aid in risk stratification and the provision of optimal care.
Subject(s)
Abdominal Injuries , Acute Kidney Injury , Humans , Logistic Models , Retrospective Studies , Acute Kidney Injury/diagnosis , Acute Kidney Injury/etiology , Machine LearningABSTRACT
The prognosis of early gastric cancer (EGC) with submucosal invasion is favorable; however, several cases of recurrence have been reported even after curative gastrectomy. This study aimed to investigate risk factors and evaluate the clinical significance of the number of retrieved lymph nodes (LNs) in EGC with submucosal invasion. We retrospectively analyzed the data of 443 patients with gastric cancer with submucosal invasion after curative gastrectomy for recurrent risk factors. Recurrence was observed in 22 of the 443 gastric cancer patients with submucosal invasion. In the univariate analysis, the risk factors for recurrence were the number of retrieved LNsâ ≤â 25 and node metastasis. In the multivariate analysis, retrieved LNsâ ≤â 25 (hazard ratio [HR]â =â 5.754, P-valueâ =â .001) and node metastasis (HRâ =â 3.031, P-valueâ =â .029) were independent risk factors for recurrence after curative gastrectomy. Body mass index was related to retrieved LNsâ ≤â 25 in univariate and multivariate analyses (HRâ =â .510, Pâ =â .002). The number of retrieved LNs and node metastases were independent risk factors for EGC with submucosal invasion. For EGC with submucosal invasion, retrieved LNsâ >â 25 are necessary for appropriate diagnosis and treatment.
Subject(s)
Stomach Neoplasms , Humans , Stomach Neoplasms/pathology , Lymphatic Metastasis/pathology , Retrospective Studies , Lymph Nodes/surgery , Lymph Nodes/pathology , GastrectomyABSTRACT
BACKGROUND: Aortic intramural hematoma (IMH) associated with aortic branch tear and intramurally located pseudoaneurysm after blunt trauma has not been reported. Here, we report a case of progressive type A aortic IMH associated with a pseudoaneurysm arising from the injured proximal renal artery after blunt trauma. CASE SUMMARY: During logging operations, a 66-year-old man experienced blunt force trauma after being injured by a fallen tree. He arrived at our trauma center with a left flank pain complaint. Computed tomography (CT) revealed a pseudoaneurysm arising from the proximal renal artery (localized within the aortic media) and Stanford type A IMH. A covered stent was deployed along the left main renal artery, bridging the pseudoaneurysm and covering the parent artery, successfully excluding the pseudoaneurysm as confirmed using aortography. However, although the degree of the pseudoaneurysm decreased, follow-up CT revealed remnant pseudoaneurysm, likely caused by an endoleak. Subsequently, a covered stent was additionally installed through the previously deployed covered stent. Successful exclusion of the pseudoaneurysm was confirmed using final aortography. In the 7-mo follow-up CT scan, the IMH and pseudoaneurysm completely disappeared with no evidence of stent-related complications. CONCLUSION: Endovascular treatment such as stent-graft placement can be an effective and safe treatment for traumatic renal artery injury.
ABSTRACT
Spontaneously ruptured hepatocellular carcinoma (srHCC) is a fatal complication of hepatocellular carcinoma (HCC). In addition, emergency treatment is frequently fraught with difficulties. This study aimed to investigate the prognosis and recurrence pattern in patients undergoing hepatectomy for the srHCC. This retrospective study included 11 patients with srHCC treated using either emergency hepatectomy or emergency transarterial embolization (TAE) followed by staged hepatectomy between January 2015 and December 2019. The patients visited the emergency room because of a sudden rupture of HCC without being diagnosed with HCC. We analyzed the prognosis, recurrence rate, and survival in these patients after hepatectomy. Four of the 11 patients in this study were classified as Child-Pugh class A and 7 as Child-Pugh class B. Nine patients visited for sudden onset of abdominal pain, and 2 for sudden onset of shock. The median hemoglobin level at the time of the visit was 11.5 g/dL (interquartile range: 9.8-12.7). Five patients underwent one-stage hepatectomy and 6 underwent emergency TAE hemostasis followed by staged hepatectomy. Median overall survival and recurrence-free survivals were 23 and 15 months, respectively. Recurrence occurred in 7 patients (4 in the one-stage group and 3 in the staged group). Among patients with recurrence, 6 had intrahepatic recurrence and 3 peritoneal metastases. Patients with srHCC who undergo staged hepatectomy can achieve a relatively good prognosis. The most common sites of recurrence after hepatectomy are intrahepatic and peritoneal. Peritoneal metastases are more likely to occur after one-stage hepatectomy.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Peritoneal Neoplasms , Hemoglobins , Humans , Liver Neoplasms/pathology , Peritoneal Neoplasms/complications , Retrospective Studies , Rupture/complications , Rupture, Spontaneous/complications , Rupture, Spontaneous/surgeryABSTRACT
Background: We aimed to investigate the outcomes after delayed management of ≥ Grade II blunt traumatic thoracic aortic injury (BTAI). Methods: Between January 2005 and December 2019, we retrospectively reviewed the medical records of 21 patients with ≥ Grade II thoracic aortic injury resulting from blunt trauma. Twelve patients underwent observation for the injury, whereas nine patients were transferred immediately after the diagnosis. Patients were divided into a nonoperative management group (n = 7) and delayed repair group (n = 5) based on whether they underwent thoracic endovascular aneurysm repair or surgery. Results: The most common dissection type was DeBakey classification IIIa (n = 9). Five patients underwent delayed surgery (including aneurysm repair), with observation periods ranging from 1 day to 36 months. The delayed repair group exhibited higher injury severity scores than the nonoperative management group (n = 7). The nonoperative management group was followed-up with blood pressure management without a change in status for a period ranging from 3 to 96 months. Conclusions: Our findings indicated that conservative management may be appropriate for select patients with Grade II/III BTAI, especially those exhibiting hemodynamic stability with anti-impulse therapy and minimally sized pseudoaneurysms. However, further studies are required to identify the risk factors for injury progression and long-term outcomes.
ABSTRACT
Duodenal stump fistula (DSF) is one of the most serious complications of gastrectomy. The mean time to diagnosis of DSF is approximately 9 days after operation. Our report describes an extremely rare case of delayed DSF 144 days after a laparoscopic distal gastrectomy. A 58-year-old man with drug-induced liver cirrhosis (Child-Pugh class A) underwent laparoscopic distal gastrectomy with Billroth-II reconstruction for early gastric cancer. On postoperative day 1, he underwent reoperation because of intra-abdominal bleeding. Ongoing bleeding was observed in the stapler line of the duodenal stump and was controlled using metallic surgical clips. The patient was discharged on postoperative day 14, without complications. After 144 days following the first operation, he visited the emergency room with right flank pain and high fever. Computed tomography revealed free air and abscess near the duodenal stump site. Emergency laparotomy, abscess unlooping, and drain insertion were performed. After surgery, bile was drained by intra-abdominal drainage, and fistulography showed a duodenal fistula. The patient was discharged 55 days after his third surgery. This is an extremely rare case of DSF, which may be caused by the metallic surgical clips used for hemostasis of the duodenal stump stapler line. We believe that the use of metallic surgical clips for hemostasis of the duodenal stump after Billroth-II reconstruction should be avoided.
Subject(s)
Duodenal Diseases , Intestinal Fistula , Laparoscopy , Stomach Neoplasms , Abscess/surgery , Duodenal Diseases/etiology , Duodenal Diseases/surgery , Gastrectomy/adverse effects , Gastrectomy/methods , Humans , Intestinal Fistula/complications , Intestinal Fistula/surgery , Laparoscopy/adverse effects , Male , Middle Aged , Postoperative Complications/etiology , Postoperative Complications/surgery , Stomach Neoplasms/complications , Stomach Neoplasms/surgeryABSTRACT
Although the mean corpuscular volume (MCV) has been associated with various diseases, these associations in relation to the age-related trends in MCV remain unclear. Therefore, we used a dataset with over one million values to identify the relationship between ageing and MCV changes. All laboratory data obtained between November 1998 and November 2019 at Chungbuk National University Hospital were retrospectively collected. After excluding cases with missing values for individual complete blood count parameters, outlier MCV values, and ages less than 1 year and more than 88 years, 977,335 MCV values were obtained from 309,393 patients. Principal component analysis of blood components with ages and analysis of the median value changes for each blood component across decade-wise age groups were conducted to identify relationships between ageing and changes in blood components. The median values of MCV showed gradual increments with age. The linear relationship for patients aged 1-25 years had a larger slope than that for patients aged 26-88 years. For MCV, the equation for patients aged 1-25 years was 0.40*(age) + 81.24 in females and 0.45*(age) + 79.58 in males. The equation for patients aged 26-90 years was 0.04*(age) + 88.97 in females and 0.06*age + 88.30 in males. Among patients aged >40 years, the MCV value was higher in men than in women. Analysis of a large dataset showed that the MCV gradually increased with age and the linear relationship differed between patients aged 1-25 and 26-88 years.
Subject(s)
Anemia , Erythrocyte Indices , Blood Cell Count , Female , Humans , Male , Retrospective StudiesABSTRACT
RATIONALE: Gangliocytic paraganglioma (GP) is a rare tumor that mostly develops in the duodenum and is composed of the following 3 cell types: epithelioid endocrine, spindle-like, and ganglion-like cells. It manifests as symptoms such as abdominal pain, gastrointestinal bleeding, and weight loss; however, occasionally, it is incidentally detected on endoscopic or radiologic examinations. Although GP is usually benign, it can metastasize to the lymph nodes, and distant metastases have been reported in some cases. PATIENT CONCERNS: A 46-year-old woman presented with anemia on health surveillance examination. She had no other specific symptoms, and her physical examination did not reveal any abnormal finding. DIAGNOSIS: Endoscopic ultrasound-guided fine-needle aspiration biopsy was performed, and the endoscopist obtained samples from the inner side of the ampullary mass. Pathological examination suggested GP or a neuroendocrine tumor. INTERVENTIONS: Initially, we planned transduodenal ampullectomy with lymph node excision. However, there was severe fibrosis around the duodenum, and an examination of a frozen biopsy sample from the periduodenal lymph node showed atypical cells in the lymph node. Therefore, we performed pylorus-preserving pancreaticoduodenectomy with lymph node dissection. OUTCOMES: The final pathological diagnosis was GP located in the ampulla of Vater. The GP showed lymphovascular and perineural invasion and invaded the duodenal wall. Furthermore, 4 out of 18 harvested lymph nodes showed metastasis. LESSONS: We described a case of GP confined to the ampulla with regional lymph node metastasis and reviewed published literature on ampullary GP with lymph node metastasis.
Subject(s)
Duodenal Neoplasms , Paraganglioma , Duodenal Neoplasms/pathology , Endoscopic Ultrasound-Guided Fine Needle Aspiration , Female , Humans , Lymphatic Metastasis , Middle Aged , Pancreaticoduodenectomy , Paraganglioma/diagnosis , Paraganglioma/pathology , Paraganglioma/surgeryABSTRACT
BACKGROUND: Patients on dialysis have numerous gastrointestinal problems related to uremia, which may represent concealed cholecystitis. We investigated the incidence and risk of acute cholecystitis in dialysis patients and used national health insurance data to identify acute cholecystitis in Korea. METHODS: The Korean National Health Insurance Database was used, with excerpted data from the insurance claim of the International Classification of Diseases code of dialysis and acute cholecystitis treated with cholecystectomy. We included all patients who commenced dialysis between 2004 and 2013 and selected the same number of controls via propensity score matching. RESULTS: A total of 59,999 dialysis and control patients were analyzed; of these, 3,940 dialysis patients (6.6%) and 647 controls (1.1%) developed acute cholecystitis. The overall incidence of acute cholecystitis was 8.04-fold higher in dialysis patients than in controls (95% confidence interval, 7.40-8.76). The acute cholecystitis incidence rate (incidence rate ratio, 23.13) was especially high in the oldest group of dialysis patients (aged ≥80 years) compared with that of controls. Dialysis was a significant risk factor for acute cholecystitis (adjusted hazard ratio, 8.94; 95% confidence interval, 8.19-9.76). Acute cholecystitis developed in 3,558 of 54,103 hemodialysis patients (6.6%) and in 382 of 5,896 patients (6.5%) undergoing peritoneal dialysis. CONCLUSION: Patients undergoing dialysis had a higher incidence and risk of acute cholecystitis than the general population. The possibility of a gallbladder disorder developing in patients with gastrointestinal problems should be considered in the dialysis clinic.
ABSTRACT
OBJECTIVE: We aimed to identify the risk factors for ventilator-associated pneumonia in patients admitted to critical care after a torso injury. METHODS: We retrospectively evaluated 178 patients with torso injury aged >15 years who were intubated in the emergency room and placed on a mechanical ventilator after intensive care unit (ICU) admission, survived for >48 hours, had thoracic and/or abdominal injuries, and had no end-stage renal disease. We compared clinico-laboratory variables between ventilator-associated pneumonia (n = 54, 30.3%) and non-ventilator-associated pneumonia (n = 124, 69.7%) groups. Risk factors for ventilator-associated pneumonia were assessed using multivariable logistic regression analysis. RESULTS: Ventilator-associated pneumonia was associated with a significantly longer stay in the ICU (11.3 vs. 6.8 days) and longer duration of mechanical ventilation (7 vs. 3 days). Injury Severity Score (adjusted odds ratio [AOR]: 1.048; 95% confidence interval [CI]: 1.008-1.090), use of vasopressors (AOR: 2.541; 95% CI: 1.121-5.758), and insertion of a nasogastric tube (AOR: 6.749; 95% CI: 2.397-18.999) were identified as independent risk factors of ventilator-associated pneumonia. CONCLUSION: Ventilator-associated pneumonia in patients with torso injury who were admitted to the ICU was highly correlated with Injury Severity Score, use of vasopressors, and insertion of a nasogastric tube.
Subject(s)
Pneumonia, Ventilator-Associated , Humans , Intensive Care Units , Pneumonia, Ventilator-Associated/epidemiology , Pneumonia, Ventilator-Associated/etiology , Retrospective Studies , Risk Factors , TorsoABSTRACT
INTRODUCTION AND IMPORTANCE: Fibrosarcoma is a rare malignant tumor comprising spindle-shaped fibroblasts exhibiting variable collagen production. Adult-type fibrosarcoma (AFS) mainly occurs in people aged between 30 and 80 years, primarily in the deep soft tissues of the trunk, neck, and extremities, especially in areas surrounding bones. Juvenile fibrosarcoma(JFS) is a type of AFS that occurs in adolescents and rarely develops in the abdominal cavity. CASE PRESENTATION: A 13-year-old girl presented with right upper quadrant pain for 5 days. Abdomen and pelvis computed tomography showed a 12 × 6-cm, ill-defined, lobulated, solid, cystic mass in the abdominal cavity. On laparoscopy, there were two masses in the abdominal cavity. One abutted the stomach and severely adhered to the gallbladder. The second mass was located between the transverse colon and duodenum, and it was surrounded by the omentum. The tissues surrounding the masses were finely dissected, and the two masses were excised completely. The patient was discharged without complications on post-operative day 7. CLINICAL DISCUSSION: JFS, AFS in adolescents, is a rare malignant tumor. And there have been no reported cases of multiple JFS in abdominal cavity. Surgical excision is the gold standard of treatment for localized AFS, and the laparoscopic approach for minimal tumor handling is beneficial. CONCLUSION: We describe a rare case of multiple intra-abdominal juvenile fibrosarcoma, managed through laparoscopic surgery.
ABSTRACT
This paper addresses ground target tracking (GTT) for airborne radar. Digital terrain elevation data (DTED) are widely used for GTT as prior information under the premise that ground targets are constrained on terrain. Existing works fuse DTED to a tracking filter in a way that adopts only the assumption that the position of the target is constrained on the terrain. However, by kinematics, it is natural that the velocity of the moving ground target is constrained as well. Furthermore, DTED provides neither continuous nor accurate measurement of terrain elevation. To overcome such limitations, we propose a novel soft terrain constraint and a constraint-aided particle filter. To resolve the difficulties in applying the DTED to the GTT, first, we reconstruct the ground-truth terrain elevation using a Gaussian process and treat DTED as a noisy observation of it. Then, terrain constraint is formulated as joint soft constraints of position and velocity. Finally, we derive a Soft Terrain Constrained Particle Filter (STC-PF) that propagates particles while approximately satisfying the terrain constraint in the prediction step. In the numerical simulations, STC-PF outperforms the Smoothly Constrained Kalman Filter (SCKF) in terms of tracking performance because SCKF can only incorporate hard constraints.
ABSTRACT
INTRODUCTION AND IMPORTANCE: Heterotopic mesenteric ossification (HMO) is a rare condition that can be hereditary or nonhereditary. It can lead to small bowel obstruction, which may require corrective surgery. Most affected patients have a history of abdominal surgery or trauma. Spontaneously occurring HMO is even rarer, with only 7 cases reported till date. There has been no previous report of spontaneous peripancreatic HMO. CASE PRESENTATION: A 60-year-old man presented with complaints of recurrent nausea and vomiting for 2 months. Esophagogastroduodenoscopy revealed luminal stenosis and edematous changes involving the second and third parts of the duodenum but not its complete obstruction. Abdominopelvic computed tomography showed faintly enhanced thickening of the involved duodenal walls along with mild dilatation of the common bile duct. Considering the possibility of periampullary cancer, we performed a pylorus-preserving pancreaticoduodenectomy. Histopathological examination confirmed the diagnosis of HMO with extensive fibrosis involving the peripancreatic soft tissue. CLINICAL DISCUSSION: The peripancreatic HMO with severe fibrosis can occur duodenal stenosis, and it is mimicking periampullary cancer. However, the preoperative diagnosis of spontaneous HMO is difficult, and a diagnosis confirmed after surgery. CONCLUSION: Herein, we described our experience of managing a rare case of duodenal stenosis due to spontaneous HMO involving peripancreatic tissue.
ABSTRACT
Pancreatic candidiasis can develop in patients with acute pancreatitis, compromised immune responses, or iatrogenic intervention. This paper reports a case of pancreatic candidiasis presenting as a solid pancreatic mass in a patient without the risk factors. A previously healthy 37-year-old man visited the emergency department with left flank pain. Abdominal CT revealed a 5 cm, irregular heterogeneous enhancing mass accompanied by a left adrenal mass. Positron emission tomography-computed tomography and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) could not discriminate pancreatic cancer from infectious disease. A laparoscopic exploration was performed for an accurate diagnosis. After distal pancreatectomy with splenectomy and left adrenalectomy, pancreatic candidiasis and adrenal cortical adenoma were diagnosed based on the pathology findings. His condition improved after the treatment with fluconazole. This paper reports a case of primary pancreatic candidiasis mimicking pancreatic cancer in an immunocompetent patient with a review of the relevant literature.
Subject(s)
Candidiasis, Invasive , Pancreatic Neoplasms/diagnosis , Pancreatitis, Acute Necrotizing , Adult , Antifungal Agents/therapeutic use , Candidiasis, Invasive/diagnosis , Candidiasis, Invasive/drug therapy , Candidiasis, Invasive/microbiology , Candidiasis, Invasive/surgery , Diagnosis, Differential , Endoscopic Ultrasound-Guided Fine Needle Aspiration , Fluconazole/therapeutic use , Humans , Male , Pancreas/diagnostic imaging , Pancreas/pathology , Pancreas/surgery , Pancreatectomy , Pancreatitis, Acute Necrotizing/diagnosis , Pancreatitis, Acute Necrotizing/drug therapy , Pancreatitis, Acute Necrotizing/microbiology , Pancreatitis, Acute Necrotizing/surgery , Positron Emission Tomography Computed Tomography , Tomography, X-Ray ComputedABSTRACT
This paper presents closed-form optimal cooperative guidance laws for two UAVs under information constraints that achieve the required relative approach angle. Two UAVs cooperate to optimize a common cost function under a coupled constraint on terminal velocity vectors and the information constraint which defines the sensor information availability. To handle the information constraint, a general two-player partially nested decentralized optimal control problem is considered in the continuous finite-horizon time domain. It is shown that under the state-separation principle the optimal solution of the decentralized control problem can be obtained by solving two centralized subproblems which cover the prediction problem for the information-deficient player and the prediction error minimization problem for the player with full information. Based on the solution of the decentralized optimal control problem, the explicit closed-form cooperative guidance laws that can be efficiently implemented on conventional guidance computers are derived. The performance of the proposed guidance laws is investigated on both centralized and decentralized cooperative scenarios with nonlinear engagement kinematics of networked two-UAV systems.
ABSTRACT
A spacecraft attitude control system provides mechanical and electrical control to achieve the required functions under various mission scenarios. Although generally designed to be highly reliable, mission failure can occur if anomalies occur and the attitude control system fails to properly orient and stabilize the spacecraft. Because accessing spacecraft to directly repair such problems is usually infeasible, developing a continuous condition monitoring model is necessary to detect anomalies and respond accordingly. In this study, a method for detecting anomalies and characterizing failures for spacecraft attitude control systems is proposed. Herein, features are extracted from multidimensional time-series data of a simulation of the attitude control system. Then, the artificial neural network learning algorithms based on two types of generation models are applied. A Bayesian optimization algorithm with a Gaussian process is used to optimize the hyperparameters for the neural network to improve the performance. The performance is evaluated based on the reconstruction error through the algorithm using the newly generated data not used for learning as input data. Results show that the detection performance depends on the operating characteristics of each submode in the operation scenarios and type of generation model. The diagnostic results are monitored to detect anomalies in operation modes and scenarios.