Objective
The aim of this article is to focus on etiology, risk factors, clinical presentation and classification systems of acute and chronic PVT as well as focusing on current diagnostic and ...therapeutic options for the management of acute and chronic PVT.
Results
PVT represents a serious clinical concern in cirrhotic patients and in those with specific local or systemic risk factors. The rate and extent of thrombus formation can significantly impact patient presentation and the resulting clinical outcomes. The presentation of acute PVT can range from abdominal pain to intestinal ischemia/infarction and even death, while chronic PVT can remain clinically silent. A number of imaging modalities including US, CT and MRI can be used to confirm the diagnosis. In addition to addressing underlying risk factors, AC therapy forms a cornerstone of treatment and has demonstrated efficacy in both acute and chronic settings. Proper caution should be used when initiating AC therapy in cirrhotic patients given their underlying coagulopathic status with attention now being paid to NOACs and LMWH. For patients with bowel ischemia, extensive thrombosis, contraindications or poor response to AC, or for those with co-morbidities that preclude AC, minimally invasive endovascular techniques offer alternative treatment options.
Conclusion
Familiarity with the etiology, clinical presentation and classification of PVT optimize early detection and incorporate effective therapeutic options, the management of these complex patients should be undertaken by a multidisciplinary team. Minimally invasive catheter-based therapies and endovascular portosystemic shunt creation demonstrated efficacy in the treatment of AC-resistant patients and for patients with extensive or complicated disease.
Objective Ischemia-reperfusion (IR) injury is a significant problem in the management of patients with acute limb ischemia. Despite rapid restoration of blood flow after technically successful open ...and endovascular revascularization, complications secondary to IR injury continue to occur and limit clinical success. Our aim was to create a murine model of hind limb IR injury to examine the role of Toll-like receptor-4 (TLR4) and to determine whether inactive TLR4 led to a decrease in the detection of neutrophil extracellular traps (NETs), which are known to be highly thrombogenic and may mediate microvascular injury. Methods A calibrated tension tourniquet was applied to unilateral hind limb of wild-type (WT) and TLR4 receptor mutant (TLR4m) mice for 1.5 hours to induce ischemia and then removed to initiate reperfusion. At the end of 48 hours of reperfusion, mice were euthanized and hind limb tissue and serum specimens were collected for analysis. Hematoxylin and eosin-stained sections of hind limb skeletal muscle tissue were examined for fiber injury. For immunohistochemistry, mouse monoclonal antihistone H2A/H2B/DNA complex antibody to detect NETs and rabbit polyclonal antimyeloperoxidase antibody were used to identify infiltrating cells containing myeloperoxidase. Muscle adenosine triphosphate levels, nuclear factor (NF)-κB activity, the α-subunit of inhibitor of NF-κB light polypeptide gene enhancer, poly (adenosine diphosphate-ribose) polymerase activity, and inducible nitric oxide synthase expression were measured. Systemic levels of keratinocyte-derived chemokine, monocyte chemotactic protein-1, and vascular endothelial growth factor in the serum samples were also examined. Results IR injury in the hind limb of WT mice demonstrated significant levels of muscle fiber injury, decreased energy substrates, increased NF-κB activation, decreased levels of α-subunit of inhibitor of NF-κB light polypeptide gene enhancer, increased inducible nitric oxide synthase expression, and increased poly (adenosine diphosphate-ribose) polymerase activity levels compared with the TLR4m samples. Additionally, there was marked decrease in the level of neutrophil and monocyte infiltration in the TLR4m mice, which corresponded to similar levels of decreased NET detection in the interstitial space and in microvascular thrombi. In situ nuclease treatment of WT tissue sections significantly diminished the level of NET immunostaining, demonstrating the specificity of the antibody to detect NETs and suggesting a potential role for nuclease treatment in IR injury. Conclusions These results suggest a pivotal role for TLR4 in mediating hind limb IR injury and suggest that NETs may contribute to muscle fiber injury.
To extend the investigation of price transparency and variability to medical imaging.
Eighteen upper-tier academic hospitals identified by U.S. News & World Report and 14 of the 100 largest private ...radiology practices in the country identified by the Radiology Business Journal were contacted by telephone between December 2013 and February 2014 to determine the cash price for a noncontrast head CT. The price for a noncontrast head CT was chosen to assess price transparency in medical imaging because it represents a standard imaging examination with minimal differences in quality.
Fourteen upper-tier academic hospitals (78%) and 11 private practices (79%) were able to provide prices for a noncontrast head CT. There was no significant difference between the proportions of upper-tier academic hospitals and private practices that were able to provide prices for a noncontrast head CT (P = .96). The average total price for the upper-tier academic hospitals was $1,390.12 ± $686.13, with the price ranging from $391.62 to $2,015. The average total price for the private practices was $681.60 ± $563.58, with the total price ranging from $211 to $2,200.
Prices for a noncontrast head CT study were readily available from the vast majority of upper-tier academic hospitals and private practices, although there was tremendous variation in the price estimates both within and between the upper-tier academic hospitals and private practices. Routine medical imaging thus appears to be more price transparent compared with other health care services.
Background/Objectives. Embolization of the left gastric artery (LGA), which preferentially supplies the gastric fundus, has been shown to produce weight loss in animal models. However, weight loss ...after LGA embolization in humans has not been previously established. The aim of this study was to evaluate postprocedural weight loss in patients following LGA embolization. Subjects/Methods. A retrospective analysis of the medical records of patients who underwent LGA embolization for upper gastrointestinal (GI) bleeding was performed. Postprocedural weight loss in this group was compared to a control group of patients who had undergone embolization of other arteries for upper GI bleeding. Results. The experimental group (N=19) lost an average of 7.3% of their initial body weight within three months of LGA embolization, which was significantly greater than the 2% weight loss observed in the control group (N=28) (P=0.006). No significant differences were seen between the groups in preprocedural body mass index (BMI), age, postprocedural care in the intensive care unit, history of malignancy, serum creatinine, or left ventricular ejection fraction. Conclusions. The current data suggest that body weight in humans may be modulated via LGA embolization. Continued research is warranted with prospective studies to further investigate this phenomenon.
May-Thurner syndrome(MTS) is the pathologic compression of the left common iliac vein by the right common iliac artery, resulting in left lower extremity pain, swelling, and deep venous thrombosis. ...Though this syndrome was first described in 1851, there are currently no standardized criteria to establish the diagnosis of MTS. Since MTS is treated by a wide array of specialties, including interventional radiology, vascular surgery, cardiology, and vascular medicine, the need for an established diagnostic criterion is imperative in order to reduce misdiagnosis and inappropriate treatment. Although MTS has historically been diagnosed by the presence of pathologic features, the use of dynamic imaging techniques has led to a more radiologic based diagnosis. Thus, imaging plays an integral part in screening patients for MTS, and the utility of a wide array of imaging modalities has been evaluated. Here, we summarize the historical aspects of the clinical features of this syndrome. We then provide a comprehensive assessment of the literature on the efficacy of imaging tools available to diagnose MTS. Lastly, we provide clinical pearls and recommendations to aid physicians in diagnosing the syndrome through the use of provocative measures.
Immunotherapy is a class of promising anticancer treatments that has recently gained attention due to surging numbers of FDA approvals and extensive preclinical studies demonstrating efficacy. ...Nevertheless, further clinical implementation has been limited by high variability in patient response to different immunotherapeutic agents. These treatments currently do not have reliable predictors of efficacy and may lead to side effects. The future development of additional immunotherapy options and the prediction of patient‐specific response to treatment require advanced screening platforms associated with accurate and rapid data interpretation. Advanced engineering approaches ranging from sequencing and gene editing, to tumor organoids engineering, bioprinted tissues, and organs‐on‐a‐chip systems facilitate the screening of cancer immunotherapies by recreating the intrinsic and extrinsic features of a tumor and its microenvironment. High‐throughput platform development and progress in artificial intelligence can also improve the efficiency and accuracy of screening methods. Here, these engineering approaches in screening cancer immunotherapies are highlighted, and a discussion of the future perspectives and challenges associated with these emerging fields to further advance the clinical use of state‐of‐the‐art cancer immunotherapies are provided.
Advanced engineering approaches and progress in artificial intelligence can contribute to the development of cancer immunotherapy by uncovering alternative treatment targets and identifying hallmarks of treatment response, efficacy, and side effects. Screening approaches, including sequencing, gene editing, tumor organoids engineering, bioprinting, and organs‐on‐a‐chip, combined with high‐throughput screening and artificial intelligence are promising in accelerating broader application of cancer immunotherapy for a larger population.
Air embolism is a rarely encountered but much dreaded complication of surgical procedures that can cause serious harm, including death. Cases that involve the use of endovascular techniques have a ...higher risk of air embolism; therefore, a heightened awareness of this complication is warranted. In particular, central venous catheters and arterial catheters that are often placed and removed in most hospitals by a variety of medical practitioners are at especially high risk for air embolism. With appropriate precautions and techniques it can be preventable. This article reviews the causes of air embolism, clinical management and prevention techniques.
Endovascular embolization to treat vascular hemorrhage involves pushing coil‐shaped metal wires into the artery repeatedly until they are densely packed to slow the blood flow and clot. However, coil ...embolization is associated with high rebleeding rates, unpredictable economics and, most importantly, they rely on the patient's ability to make a clot. These issues are exacerbated when the patient is anticoagulated or coagulopathic. A novel bioengineered tantalum‐loaded nanocomposite hydrogel for gel embolic material (Ta‐GEM) that can be rapidly delivered using clinical catheters for instant hemostasis regardless of the coagulopathic state is reported. Ta‐GEM formulation is visible by most of the clinically available imaging modalities including ultrasound, computed tomography, magnetic resonance imaging, and fluoroscopy without significant artifact. In addition, Ta‐GEM can be retrieved, allowing temporary vascular occlusion, and it can be used to rescue cases of failed coil embolization. Ta‐GEM occlusion of first‐order arteries such as the renal artery and iliac artery in a swine model is found to be safe and durable; by 28 days, 75% of the injected Ta‐GEM in the arterial lumen is replaced by dense connective tissue. Altogether, this study demonstrates that Ta‐GEM has many advantages over the current technologies and has potential applications in clinical practice.
Endovascular embolization is performed to treat various vascular diseases including hemorrhage, aneurysms, and vascular malformations. A tantalum microparticle‐loaded shear‐thinning gel embolic material (Ta‐GEM) that can be rapidly delivered into diseased arteries using clinical catheters to achieve rapid hemostasis is reported. In large animal models, Ta‐GEM leads to a durable occlusion without recanalization and outperforms coils and gelfoam under coagulopathic conditions.
Preoperative planning is critical for success in the surgical suite. Current techniques for surgical planning are limited; clinicians often rely on prior experience and medical imaging to guide the ...decision-making process. Furthermore, two-dimensional (2D) presentations of anatomical structures may not accurately portray their three-dimensional (3D) complexity, often leaving physicians ill-equipped for the procedure. Although 3D postprocessed images are an improvement on traditional 2D image sets, they are often inadequate for surgical simulation. Medical 3D printing is a rapidly expanding field and could provide an innovative solution to current constraints of preoperative planning. As 3D printing becomes more prevalent in medical settings, it is important that clinicians develop an understanding of the technologies, as well as its uses. Here, we review the fundamentals of 3D printing and key aspects of its workflow. The many applications of 3D printing for preoperative planning are discussed, along with their challenges.
Radiogenomics is a computational discipline that identifies correlations between cross-sectional imaging features and tissue-based molecular data. These imaging phenotypic correlations can then ...potentially be used to longitudinally and non-invasively predict a tumor's molecular profile. A different, but related field termed radiomics examines the extraction of quantitative data from imaging data and the subsequent combination of these data with clinical information in an attempt to provide prognostic information and guide clinical decision making. Together, these fields represent the evolution of biomedical imaging from a descriptive, qualitative specialty to a predictive, quantitative discipline. It is anticipated that radiomics and radiogenomics will not only identify pathologic processes, but also unveil their underlying pathophysiological mechanisms through clinical imaging alone. Here, we review recent studies on radiogenomics and radiomics in liver cancers, including hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and metastases to the liver.
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