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Organ segmentation is a crucial task in various medical imaging applications. Many deep learning models have been developed to do this, but they are slow and require a lot of computational resources. To solve this problem, attention mechanisms are used which can locate important objects of interest within medical images, allowing the model to segment them accurately even when there is noise or artifact. By paying attention to specific anatomical regions, the model becomes better at segmentation. Medical images have unique features in the form of anatomical information, which makes them different from natural images. Unfortunately, most deep learning methods either ignore this information or do not use it effectively and explicitly. Combined natural intelligence with artificial intelligence, known as hybrid intelligence, has shown promising results in medical image segmentation, making models more robust and able to perform well in challenging situations. In this paper, we propose several methods and models to find attention regions in medical images for deep learning-based segmentation via non-deep-learning methods. We developed these models and trained them using hybrid intelligence concepts. To evaluate their performance, we tested the models on unique test data and analyzed metrics including false negatives quotient and false positives quotient. Our findings demonstrate that object shape and layout variations can be explicitly learned to create computational models that are suitable for each anatomic object. This work opens new possibilities for advancements in medical image segmentation and analysis.

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PURPOSE: Unstructured data are an untapped source for surgical prediction. Modern image analysis and machine learning (ML) can harness unstructured data in medical imaging. Incisional hernia (IH) is a pervasive surgical disease, well-suited for prediction using image analysis. Our objective was to identify optimal biomarkers (OBMs) from preoperative abdominopelvic computed tomography (CT) imaging which are most predictive of IH development. METHODS: Two hundred and twelve rigorously matched colorectal surgery patients at our institution were included. Preoperative abdominopelvic CT scans were segmented to derive linear, volumetric, intensity-based, and textural features. These features were analyzed to find a small subset of OBMs, which are maximally predictive of IH. Three ML classifiers (Ensemble Boosting, Random Forest, SVM) trained on these OBMs were used for prediction of IH. RESULTS: Altogether, 279 features were extracted from each CT scan. The most predictive OBMs found were: (1) abdominopelvic visceral adipose tissue (VAT) volume, normalized for height; (2) abdominopelvic skeletal muscle tissue volume, normalized for height; and (3) pelvic VAT volume to pelvic outer aspect of body wall skeletal musculature (OAM) volume ratio. Among ML prediction models, Ensemble Boosting produced the best performance with an AUC of 0.85, accuracy of 0.83, sensitivity of 0.86, and specificity of 0.81. CONCLUSION: These OBMs suggest increased intra-abdominopelvic volume/pressure as the salient pathophysiologic driver and likely mechanism for IH formation. ML models using these OBMs are highly predictive for IH development. The next generation of surgical prediction will maximize the utility of unstructured data using advanced image analysis and ML.

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AIM: To determine the computed tomography (CT) findings of primary and secondary achalasia and to assess the utility of CT for differentiating these conditions. METHODS: A computerized search revealed 13 patients with primary achalasia and 15 with secondary achalasia who underwent chest CT during a 10-year period. The images were reviewed to determine whether there was distal oesophageal narrowing (including the length/contour of narrowing), oesophageal dilation, oesophageal wall thickening (including degree/symmetry/pattern of thickening), a soft-tissue mass at the gastro-oesophageal junction, mediastinal adenopathy, or other findings of malignant tumour. RESULTS: Eleven (85%) of 13 patients with primary achalasia had distal oesophageal narrowing at CT that was smooth in all patients; four (31%) had oesophageal wall thickening that was smooth and symmetric in all patients; none had a soft-tissue mass at the gastro-oesophageal junction or mediastinal lymphadenopathy; and two (15%) had pulmonary metastases from unrelated lung cancers. In contrast, 12 (80%) of 15 patients with secondary achalasia had distal oesophageal narrowing at CT; 11 (73%) had distal oesophageal wall thickening that was nodular/lobulate and asymmetric in seven (64%) and smooth and symmetric in four (36%); six (40%) had a soft-tissue mass at the gastro-oesophageal junction; seven (47%) had mediastinal lymphadenopathy; and all 15 had other findings of malignant tumour. CONCLUSION: CT is a useful technique for differentiating primary and secondary achalasia. Distal oesophageal wall thickening that is nodular/lobulate and asymmetric, a soft-tissue mass at the gastro-oesophageal junction, mediastinal lymphadenopathy, and pulmonary, hepatic, or osseous metastases are findings that favour secondary achalasia.

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In patients with malignant pheochromocytoma and paraganglioma, 131I-MIBG radiotherapy can achieve an objective response rate of 30-50% with the dose limiting toxicity being hematologic. Patients with disseminated disease, who also have a few index bulky or symptomatic lesions, may benefit from the addition of targeted external beam radiotherapy alone or in combination with systemic 131I-MIBG. The records of patients with malignant paraganglioma who were treated with external beam radiotherapy at the University of Pennsylvania from February 1973 to February 2011 were reviewed in an institutional review board approved retrospective study. Of the 17 patients with tumors in the thorax, abdomen, or pelvis, 76% had local control or clinically significant symptomatic relief for at least 1 year or until death. As expected, the predominant toxicity was due to irradiation of tumor-adjacent normal tissues without clinically significant hematologic toxicity. Due to widespread systemic metastases with areas of bulky, symptomatic tumor, 5 of the 17 patients were treated with sequential 131I-MIBG (2 mCi/kg per treatment) and external beam radiotherapy to 9 sites. In these patients, all areas that were irradiated with external beam radiotherapy showed durable objective response despite all patients eventually experiencing out-of-field systemic progression requiring other treatment. Four of these patients remain alive with excellent performance status 16, 18, 23, and 24 months after external beam radiotherapy. External beam radiotherapy can be highly effective in local management of malignant paraganglioma and can be used in conjunction with 131I-MIBG due to nonoverlapping toxicities with excellent control of locally bulky tumors.

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Focal xanthogranulomatous pyelonephritis (XGP) is a chronic inflammatory condition that can mimic other disease conditions such as pyelonephritis, tuberculosis, renal abscess, renal cell carcinoma, and renal metastasis. Urinary tract infection and obstruction are considered to be predisposing factors. The clinical symptoms and imaging findings are often nonspecific so that an incorrect initial diagnosis is common. Here, we report a case of a patient with focal XGP with FDG PET/CT findings that mimic renal malignancy.

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Given the increasing complexity of both the modern health care environment and the overall patient population, reduction of medical errors is a high priority task for health policy makers and medical/surgical community alike. The problem of retained surgical foreign bodies (RSFB) has existed ever since the humans first performed surgical procedures. Retained surgical foreign bodies continue to be a significant problem with an incidence between 0.3 and 1.0 per 1,000 abdominal operations. Retained surgical foreign bodies have the potential to cause harm to the patient and carry profound professional and medico-legal consequences to surgical trainees, surgical practitioners, hospitals, and health systems. Currently, there are no known methods of entirely eliminating the occurrence of RSFB. In this manuscript, the authors discuss the available evidence with regards to risk factors associated with RSFB as well as methods of minimizing the incidence of RSFB. Modern technological advances designed to decrease the incidence of RSFB (radio-frequency tagging of surgical sponges) and improved perioperative patient processing (multiple 'checks and balances' and better provider-to-provider communication) are reviewed. The authors also explore the relationship between RSFB and surgical training with emphasis on education in early recognition, prevention, and focus on team-oriented training strategies.

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Care for the critically ill patient requires maintenance of adequate tissue perfusion/oxygenation. Continuous hemodynamic monitoring is frequently utilized to achieve these objectives. Pulmonary artery catheters (PAC) allow measurement of hemodynamic variables that cannot be measured reliably or continuously by less invasive means. Inherent to every medical intervention are risks associated with that intervention. This review categorizes complications associated with the PAC into four broad groups--complications of central venous access; complications related to PAC insertion and manipulation; complications associated with short- or long-term presence of the PAC in the cardiovascular system; and errors resulting from incorrect interpretation/use of PAC-derived data. We will discuss each of these four broad categories, followed by in-depth descriptions of the most common and most serious individual complications.

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Deep venous thrombosis and pulmonary embolism constitute common preventable causes of morbidity and mortality. The incidence of venous thromboembolism (VTE) continues to increase. Standard anticoagulation therapy may reduce the risk of fatal PE by 75% and that of recurrent VTE by over 90%. For patients who are not candidates for anticoagulation, a vena cava filter (VCF) may be beneficial. Despite a good overall safety record, significant complications related to VCF are occasionally seen. This review discusses both procedural and non-procedural complications associated with VCF placement and use. We will also discuss VCF use in the settings of pregnancy, malignancy, and the clinical need for more than one filter.

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AIM: To determine the frequency of left ventricular myocardial fat in patients with computed tomography (CT) findings of chronic left ventricular myocardial infarction, and to review the typical CT imaging features. MATERIALS AND METHODS: A retrospective search of the CT and nuclear scintigraphy reports from 1998-2005 for chronic left ventricular myocardial infarction was performed. The study group comprised those cases with available CT examinations revealing findings of chronic left ventricular myocardial infarction. Assessment for the presence of various imaging characteristics of left ventricular myocardial fat was performed in all cases. RESULTS: The frequency of left ventricular myocardial fat in 47 patients with CT evidence of chronic left ventricular myocardial infarction was 51%. Typical CT imaging features include thin linear or curvilinear fat attenuation within left ventricular myocardium, most commonly subendocardial, often associated with left ventricular wall thinning and/or calcification, predominantly in elderly men. CONCLUSIONS: Fat in the left ventricular myocardium is a common additional finding in patients with CT findings of chronic left ventricular myocardial infarction. The potential, but as yet unproven, use of this CT imaging finding is that the radiologist may be able to suggest a potential diagnosis of chronic left ventricular myocardial infarction on unenhanced, thick-section, non-gated or non-triggered chest CT imaging where identification of myocardial wall thinning may be difficult.

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Hematospermia is an anxiety provoking but otherwise generally benign and self-limited condition that is infrequently associated with significant underlying pathology, and is most often considered to be idiopathic in nature. Management with routine clinical evaluation, watchful waiting, and reassurance generally suffice without further diagnostic workup or treatment. Noninvasive imaging may play an important role in the diagnostic workup of men with hematospermia, particularly in those who are >40 years old, have other associated symptoms or signs of disease, or have persistence of hematospermia. Many entities may be encountered in association with hematospermia at imaging, and specific therapeutic interventions may be used if certain treatable underlying pathologies are coincidentally detected. In this comprehensive review, we discuss the potential etiologies, diagnostic workup, imaging techniques, relevant male pelvic anatomy, imaging appearance of specific associated pathologies, and treatment for hematospermia.

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OBJECTIVE: The purpose of this study was to assess the frequency of isolated small bowel dilatation on abdominal radiographs in patients with colonic fecal impaction and also to elucidate the cause of this finding. METHODS: A computerized search of radiology files revealed 515 patients with colonic fecal impaction on abdominal radiographs. The radiologic reports described isolated small bowel dilatation not related to other known causes of ileus or obstruction in 18 (3.5%) of the 515 patients. The films were reviewed to determine the distribution of fecal impaction and the degree and extent of small bowel dilatation. In 16 cases, medical records were reviewed to determine the clinical presentation, treatment, and course. Finally, follow-up radiographs were reviewed in four cases to determine the response to treatment of the impaction. RESULTS: All 16 patients with available medical records had abdominal symptoms. The average diameter of the dilated small bowel on abdominal radiographs was 3.7 cm. Fourteen patients (78%) had a diffuse colonic fecal impaction (nine) or a predominantly right-sided fecal impaction (five) that involved the cecum, and the remaining four (22%) had a left-sided colonic fecal impaction. All 12 patients with clinical follow-up had resolution of symptoms and all four with follow-up radiographs had resolution of small bowel dilatation after treatment of the underlying impaction. CONCLUSION: Fecal impaction should be considered in the differential diagnosis of small bowel dilatation on abdominal radiographs, as treatment of the underlying impaction usually produces a dramatic clinical response with resolution of the small bowel dilatation on follow-up radiographs.

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OBJECTIVE: The purpose of our study was to report the radiographic findings of biopsy-proven lymphoid hyperplasia of the stomach in five adult patients. CONCLUSION: Lymphoid hyperplasia of the stomach is characterized by distinctive findings on double-contrast upper gastrointestinal tract barium examinations; all five patients had innumerable tiny (1--3 mm in diameter) round frequently umbilicated nodules that carpeted the mucosa of the gastric antrum or antrum and body. Three of these five patients had associated Helicobacter pylori gastritis. The diagnosis of gastric lymphoid hyperplasia, therefore, can be suggested on the basis of the radiographic findings.

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Urologic complications of bladder-drained pancreas transplants include cystitis, duodenitis and urethritis; duodenal ulceration and perforation; and periallograft fluid collections. These complications are readily depicted radiographically, and their recognition may be crucial for patient management.

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