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Artificial intelligence (AI) has made increasing inroads in clinical medicine. In surgery, machine learning-based algorithms are being studied for use as decision aids in risk prediction and even for intraoperative applications, including image recognition and video analysis. While AI has great promise in surgery, these algorithms come with a series of potential pitfalls that cannot be ignored as hospital systems and surgeons consider implementing these technologies. The aim of this review is to discuss the progress, promise, and pitfalls of AI in surgery.

In the merit-based incentive payment system (MIPS), quality measures are considered topped out if national median performance rates are ≥95%. Quality measures worth 10 points can be capped at 7 points if topped out for ≥2 years. This report compares the availability of diagnostic radiology (DR)-related and interventional radiology (IR)-related measures worth 10 points. A total of 196 MIPS clinical quality measures were reviewed on the Center for Medicare and Medicaid Services MIPS website. There are significantly more IR-related measures worth 10 points than DR measures (2/9 DR measures vs 9/12 IR measures; P = .03), demonstrating that clinical IR services can help mixed IR/DR groups maximize their Center for Medicare and Medicaid Services payment adjustment.

OBJECTIVE. The Baveno VI consensus established guidelines to reduce unnecessary screening esophagogastroduodenoscopy (EGD) for esophageal varices (EVs). We assessed whether EVs that would require intervention at EGD can be identified on CT and evaluated if recommending EGD on the basis of CT findings would result in unnecessary EGD according to the Baveno VI consensus guidelines. MATERIALS AND METHODS. This single-institution retrospective study identified 97 contrast-enhanced CT examinations within 3 months of EGD in 93 patients with cirrhosis from 2008 to 2018. Demographic information, EGD findings, interventions, and laboratory data were reviewed. CT scans were reviewed for EVs and compared with EGD findings. Var-ices that were 4 mm or larger were considered large, and those requiring intervention were considered high risk. RESULTS. The presence of large EVs on CT was 80% sensitive and 87% specific for high-risk varices at EGD. Large EVs on CT were associated with bleeding as the indication for EGD (p = 0.03) and the presence of high-risk varices at EGD (p < 0.001). The positive predictive value that a large EV on CT corresponded to a high-risk EV at EGD was 90.4% (95% CI, 0.78-0.96). Patients with large EVs on CT were 9.4 times more likely to have a grade III or grade IV EV at EGD. CONCLUSION. Large EVs on CT correlated with high-risk varices at EGD and may be a useful indicator that EGD should be considered for confirmatory diagnosis and treatment. Recommending EGD for patients with EVs of 4 mm or larger did not result in EGD that would be deemed unnecessary according to the Baveno VI consensus guidelines.

Purpose Obesity can make bone marrow biopsy using manual landmarks as guidance technically challenging. This retrospective review was performed to assess the safety and technical success of performing bone marrow biopsies with computed tomography (CT)–guidance in obese patients. Materials and Methods This single-institution, retrospective study included 1,016 CT-guided bone marrow biopsies performed between 2009 and 2016. Thirty-four percent (n = 348) were performed in patients with a body mass index (BMI) of 30 kg/m2 or greater, and 7% (n = 75) were performed in patients with a BMI greater than 40 kg/m2. Demographic information, BMI, and complications were reviewed. The primary endpoint was technical success and procedurally related hemorrhagic complication. The electronic medical record was reviewed to identify procedural related hemorrhagic complications, Common Terminology Criteria for Adverse Events (CTCAE) Grade 3 or above. The complication rates in obese patients were compared with patients with a BMI less than 30 kg/m2. Results Biopsy was successfully performed in all patients. No biopsies resulted in a CTCAE Grade 3 or above complication. There was no difference in complication rate (0%) based on BMI. For patients with a BMI < 30 kg/m2, BMI ≥ 30 kg/m2, and BMI > 40 kg/m2, complications rates were 0% (95% confidence interval [CI]: 0–0.4%), 0% (95% CI: 0–0.9%), and 0% (95% CI: 0–4%), respectively. Conclusions CT-guided bone marrow biopsy in obese patients can be performed with a high rate of technical success and is safe. If patient body habitus limits the ability to palpate physical landmarks needed to perform bone marrow biopsy without image guidance, CT-guided bone marrow biopsy should be considered.

Background The role of CT angiography-derived fractional flow reserve (CT-FFR) in pre-transcatheter aortic valve replacement (TAVR) assessment is uncertain. Purpose To evaluate the predictive value of on-site machine learning-based CT-FFR for adverse clinical outcomes in candidates for TAVR. Materials and Methods This observational retrospective study included patients with severe aortic stenosis referred to TAVR after coronary CT angiography (CCTA) between September 2014 and December 2019. Clinical end points comprised major adverse cardiac events (MACE) (nonfatal myocardial infarction, unstable angina, cardiac death, or heart failure admission) and all-cause mortality. CT-FFR was obtained semiautomatically using an on-site machine learning algorithm. The ability of CT-FFR (abnormal if ≤0.75) to predict outcomes and improve the predictive value of the current noninvasive work-up was assessed. Survival analysis was performed, and the C-index was used to assess the performance of each predictive model. To compare nested models, the likelihood ratio χ2 test was performed. Results A total of 196 patients (mean age ± standard deviation, 75 years ± 11; 110 women [56%]) were included; the median time of follow-up was 18 months. MACE occurred in 16% (31 of 196 patients) and all-cause mortality in 19% (38 of 196 patients). Univariable analysis revealed CT-FFR was predictive of MACE (hazard ratio [HR], 4.1; 95% CI: 1.6, 10.8; P = .01) but not all-cause mortality (HR, 1.2; 95% CI: 0.6, 2.2; P = .63). CT-FFR was independently associated with MACE (HR, 4.0; 95% CI: 1.5, 10.5; P = .01) when adjusting for potential confounders. Adding CT-FFR as a predictor to models that include CCTA and clinical data improved their predictive value for MACE (P = .002) but not all-cause mortality (P = .67), and it showed good discriminative ability for MACE (C-index, 0.71). Conclusion CT angiography-derived fractional flow reserve was associated with major adverse cardiac events in candidates for transcatheter aortic valve replacement and improved the predictive value of coronary CT angiography assessment. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Choe in this issue.

Although liver biopsies (LBs) are being increasingly performed under endoscopic ultrasound (EUS) guidance, there are limited data comparing outcomes with current standard-of-care, transabdominal ultrasound (US)-guided percutaneous (PC) methods. In a randomised trial, we observed that the PC, US-guided method yielded significantly more optimal specimens, defined as specimen length of 25 mm or greater and presence of at least 11 complete portal tracts, compared with the EUS-guided method (57.9% vs 23.8%, p=0.028). Also, the PC method resulted in worse initial postprocedural pain but was less costly (US$1824 vs US$3240, p

BackgroundThe growing interest in analysis of surgical video through machine learning has led to increased research efforts; however, common methods of annotating video data are lacking. There is a need to establish recommendations on the annotation of surgical video data to enable assessment of algorithms and multi-institutional collaboration.MethodsFour working groups were formed from a pool of participants that included clinicians, engineers, and data scientists. The working groups were focused on four themes: (1) temporal models, (2) actions and tasks, (3) tissue characteristics and general anatomy, and (4) software and data structure. A modified Delphi process was utilized to create a consensus survey based on suggested recommendations from each of the working groups.ResultsAfter three Delphi rounds, consensus was reached on recommendations for annotation within each of these domains. A hierarchy for annotation of temporal events in surgery was established.ConclusionsWhile additional work remains to achieve accepted standards for video annotation in surgery, the consensus recommendations on a general framework for annotation presented here lay the foundation for standardization. This type of framework is critical to enabling diverse datasets, performance benchmarks, and collaboration.

As the relationship between CT scout landmarks and chest CT boundaries is not known, the selected scan length is often greater than necessary for the CT scan, resulting in increased radiation dose to the neck and upper abdomen. The purpose of this study is to establish the relationship between CT scout landmarks with the superior and inferior boundaries of the lungs on chest CT. Retrospective comparison of the location of the top of the first rib on frontal scout and the most inferior costophrenic angle on lateral scout to the chest CT slice just above and below the lungs. The percent of scans that would exclude part of the lung based on CT initiated at several distances above or below these landmarks was calculated. There was 2.7 times greater variability between scout landmarks and lung boundaries inferiorly than superiorly on chest CT (p

In the recent decades, the design and development of biomimetic micro air vehicles have gained increased interest by the global scientific and engineering communities. This has given greater motivation to study and understand the aerodynamics involved with winged insects. Dragonflies demonstrate unique and superior flight performance than most of the other insect species and birds. They are capable of sustained gliding flight as well as hovering and able to change direction very rapidly. Pairs of independently controlled forewings and hindwings give them an agile flying ability. This article presents a review of all published journal articles, listed in the Thomson-Reuters Web-of-Science database (1985–2018), that are related to the flight aerodynamics of dragonflies or micro air vehicles that biomimic them. The effects of dragonfly wing motions and interactions (between forewing and hindwing) that are necessary to generate the appropriate aerodynamic forces in different flight modes are described. The associated power requirements of these modes are also addressed. This article aims to provide a valuable reference to the aerodynamic design and control of dragonfly-inspired biomimetic micro air vehicles.

Analyzing surgical workflow is crucial for surgical assistance robots to understand surgeries. With the understanding of the complete surgical workflow, the robots are able to assist the surgeons in intra-operative events, such as by giving a warning when the surgeon is entering specific keys or high-risk phases. Deep learning techniques have recently been widely applied to recognizing surgical workflows. Many of the existing temporal neural network models are limited in their capability to handle long-term dependencies in the data, instead, relying upon the strong performance of the underlying per-frame visual models. We propose a new temporal network structure that leverages task-specific network representation to collect long-term sufficient statistics that are propagated by a sufficient statistics model (SSM). We implement our approach within an LSTM backbone for the task of surgical phase recognition and explore several choices for propagated statistics. We demonstrate superior results over existing and novel state-of-the-art segmentation techniques on two laparoscopic cholecystectomy datasets: the publicly available Cholec80 dataset and MGH100, a novel dataset with more challenging and clinically meaningful segment labels.

Magnetic insulators are important materials for a range of next-generation memory and spintronic applications. Structural constraints in this class of devices generally require a clean heterointerface that allows effective magnetic coupling between the insulating layer and the conducting layer. However, there are relatively few examples of magnetic insulators that can be synthesized with surface qualities that would allow these smooth interfaces and precisely tuned interfacial magnetic exchange coupling, which might be applicable at room temperature. In this work, we demonstrate an example of how the configurational complexity in the magnetic insulator layer can be used to realize these properties. The entropy-assisted synthesis is used to create single-crystal (Mg

Surgical data science (SDS) aims to improve the quality of interventional healthcare and its value through the capture, organization, analysis, and modeling of procedural data. As data capture has increased and artificial intelligence (AI) has advanced, SDS can help to unlock augmented and automated coaching, feedback, assessment, and decision support in surgery. We review major concepts in SDS and AI as applied to surgical education and surgical oncology.

Background Artificial intelligence (AI) and computer vision (CV) have revolutionized image analysis. In surgery, CV applications have focused on surgical phase identification in laparoscopic videos. We proposed to apply CV techniques to identify phases in an endoscopic procedure, peroral endoscopic myotomy (POEM). Methods POEM videos were collected from Massachusetts General and Showa University Koto Toyosu Hospitals. Videos were labeled by surgeons with the following ground truth phases: (1) Submucosal injection, (2) Mucosotomy, (3) Submucosal tunnel, (4) Myotomy, and (5) Mucosotomy closure. The deep-learning CV model—Convolutional Neural Network (CNN) plus Long Short-Term Memory (LSTM)—was trained on 30 videos to create POEMNet. We then used POEMNet to identify operative phases in the remaining 20 videos. The model’s performance was compared to surgeon annotated ground truth. Results POEMNet’s overall phase identification accuracy was 87.6% (95% CI 87.4–87.9%). When evaluated on a per-phase basis, the model performed well, with mean unweighted and prevalence-weighted F1 scores of 0.766 and 0.875, respectively. The model performed best with longer phases, with 70.6% accuracy for phases that had a duration under 5 min and 88.3% accuracy for longer phases. Discussion A deep-learning-based approach to CV, previously successful in laparoscopic video phase identification, translates well to endoscopic procedures. With continued refinements, AI could contribute to intra-operative decision-support systems and post-operative risk prediction.

The fields of computer vision (CV) and artificial intelligence (AI) have undergone rapid advancements in the past decade, many of which have been applied to the analysis of intraoperative video. These advances are driven by wide-spread application of deep learning, which leverages multiple layers of neural networks to teach computers complex tasks. Prior to these advances, applications of AI in the operating room were limited by our relative inability to train computers to accurately understand images with traditional machine learning (ML) techniques. The development and refining of deep neural networks that can now accurately identify objects in images and remember past surgical events has sparked a surge in the applications of CV to analyze intraoperative video and has allowed for the accurate identification of surgical phases (steps) and instruments across a variety of procedures. In some cases, CV can even identify operative phases with accuracy similar to surgeons. Future research will likely expand on this foundation of surgical knowledge using larger video datasets and improved algorithms with greater accuracy and interpretability to create clinically useful AI models that gain widespread adoption and augment the surgeon's ability to provide safer care for patients everywhere.

The practice of surgery involves physical manipulation of tissue to treat disease. Over many centuries, surgical outcomes have improved with increasing human knowledge and the development of novel tools. Artificial intelligence (AI) has been defined as the study of algorithms that give machines the ability to reason and perform functions such as problem solving, object and word recognition, inference of world states, and decision-making. Surgery is therefore a natural and yet complex application for AI technologies. Operations require surgeons to synthesize data from multiple sources to make decisions, identify anatomy, and carry out physical tasks in rapidly changing scenarios. Outside of the operating room, components of surgical care include diagnosis, preoperative assessment, postoperative care, assessment of outcomes, and training of surgeons. AI promises to improve the quality and efficiency of perioperative care, improve surgical decision-making, augment the physical capabilities of human surgeons, and offer many exciting opportunities for future investigation. In this chapter, past, present, and future applications of AI in surgery are reviewed.

In electric double-layer transistors (EDLTs), it is well known that the EDL formed by ionic liquids (ILs) can induce an ultrahigh carrier density at the semiconductor surface, compared to solid dielectric. However, the mechanism of device performance is still not fully understood, especially at a molecular level. Here, we evaluate the gating performance of amorphous indium gallium zinc oxide (a-IGZO) transistor coupled with a series of imidazolium-based ILs, using an approach combining of molecular dynamics simulation and finite element modeling. Results reveal that the EDL with different ion structures could produce inhomogeneous electric fields at the solid-electrolyte interface, and the heterogeneity of electric field-induced charge distributions at semiconductor surface could reduce the electrical conductance of a-IGZO during gating process. Meanwhile, a resistance network analysis was adopted to bridge the nanoscopic data with the macroscopic transfer characteristics of IL-gated transistor, and showed that our theoretical results could well estimate the gating performance of practical devices. Thereby, our findings could provide both new concepts and modeling techniques for IL-gated transistors.

Little is known about the prevalence and risk factors for coronary artery disease (CAD) in young adults, possibly owing to the limited number of anatomic studies in this patient population. The Partners YOUNG MI Registry demonstrated that myocardial infarction rates among young adults have not

To test the hypothesis that computed tomography (CT)-guided bone marrow biopsy in patients with a platelet count between 20,000/uL and 50,000/uL is safe and that preprocedure platelet transfusion is unnecessary.This single-center retrospective study included bone marrow biopsies performed between May 2009 and May 2016. The study population included 981 patients-age range, 15-93 years; average age, 57 years; 505 (51.5%) men; and 476 (48.5%) women. One hundred eighty-seven biopsies were performed in patients with a platelet count of 20,000-50,000/μL; 33 were performed in patients with a platelet count of20,000/μL. The primary endpoint was hemorrhagic complications, Society of Interventional Radiology (SIR) complication class C or above. The complication rates in thrombocytopenic patients were compared to patients with a platelet count of ≥ 50,000/uL. Ninety-five percent confidence intervals (CIs) for the complication rate in each group were also calculated.There were no SIR class C or above postprocedure bleeding-related complications, including interventions or transfusions. For patients with a platelet count of20,000/μL and of 20,000-50,000/μL, hemorrhagic complications rates were 0% (95% CI: 0-9.1%) and 0% (95% CI: 0-1.6%), respectively.CT-guided bone marrow biopsy is safe in thrombocytopenic patients, with a hemorrhagic complication rate below 1.6% for patients with a platelet count of 20,000-50,000/μL. Routine preprocedure platelet transfusion may not be necessary for patients with a platelet count of 20,000-50,000/μL.

In this study, high-performance multilayer WSe2 field-effect transistor (FET) devices with carrier type control are demonstrated via thickness modulation and a remote oxygen plasma surface treatment. Carrier type control in multilayer WSe2 FET devices with Cr/Au contacts is initially demonstrated by modulating the WSe2 thickness. The carrier type evolves with increasing WSe2 channel thickness, being p-type, ambipolar, and n-type at thicknesses 5 nm, respectively. The thickness-dependent carrier type is attributed to changes in the bandgap of WSe2 as a function of the thickness and the carrier band offsets relative to the metal contacts. Furthermore, we present a strong hole carrier doping effect via remote oxygen plasma treatment. It non-degenerately converts n-type characteristics into p-type and enhances field-effect hole mobility by three orders of magnitude. This work demonstrates progress towards the realization of high-performance multilayer WSe2 FETs with carrier type control, potentially extendable to other transition metal dichalcogenides, for future electronic and optoelectronic applications.

Purpose To review a single-center experience with the cortical tangential approach during computed tomography (CT)-guided native medical renal biopsy and to evaluate its efficacy and safety compared with those of a non-cortical tangential approach. Materials and Methods This retrospective study received institutional review board approval, with a waiver of the HIPAA requirement for informed consent. The number of cores, glomeruli, and complications were reviewed in 431 CT-guided medical renal biopsies performed between July 2007 and September 2015. A biopsy followed a cortical tangential approach if the needle path was parallel to the renal cortical surface, at a depth closer to the renal capsule than the renal pelvic fat. A sample was considered adequate if the biopsy yielded at least 10 glomeruli at light microscopy, one glomerulus at immunofluorescence microscopy, and one glomerulus at electron microscopy. The χ

Coronary artery calcium (CAC) is often identified on routine chest computed tomography (CT). The purpose of our study was to evaluate whether ordinal scoring of CAC on non-gated, routine chest CT is an accurate predictor of Agatston score ranges in a community-based population, and in particular to determine the accuracy of an ordinal score of zero on routine chest CT.Two thoracic radiologists reviewed consecutive same-day ECG-gated and routine non-gated chest CT scans of 222 individuals. CAC was quantified using the Agatston scoring on the ECG-gated scans, and using an ordinal method on routine scans, with a score from 0 to 12. The pattern and distribution of CAC was assessed. The correlation between routine exam ordinal scores and Agatston scores in ECG-gated exams, as well as the accuracy of assigning a zero calcium score on routine chest CT was determined.CAC was most prevalent in the left anterior descending coronary artery in both single and multi-vessel coronary artery disease. There was a strong correlation between the non-gated ordinal and ECG-gated Agatston scores (r = 0.811, p 0.01). Excellent inter-reader agreement (k = 0.95) was shown for the presence (total ordinal score ≥1) or absence (total ordinal score = 0) of CAC on routine chest CT. The negative predictive value for a total ordinal score of zero on routine CT was 91.6% (95% CI, 85.1-95.9). Total ordinal scores of 0, 1-3, 4-5, and ≥6 corresponded to average Agatston scores of 0.52 (0.3-0.8), 98.7 (78.2-117.1), 350.6 (264.9-436.3) and 1925.4 (1526.9-2323.9).Visual assessment of CAC on non-gated routine chest CT accurately predicts Agatston score ranges, including the zero score, in ECG-gated CT. Inclusion of this information in radiology reports may be useful to convey important information on cardiovascular risk, particularly premature atherosclerosis in younger patients.

Due to the limit in computing power arising from the Von Neumann bottleneck, computational devices are being developed that mimic neuro-biological processing in the brain by correlating the device characteristics with the synaptic weight of neurons. This platform combines ionic liquid gating and electrowetting for programmable placement/connectivity of the ionic liquid. In this platform, both short-term potentiation (STP) and long-term potentiation (LTP) are realized via electrostatic and electrochemical doping of the amorphous indium gallium zinc oxide (aIGZO), respectively, and pulsed bias measurements are demonstrated for lower power considerations. While compatible with resistive elements, we demonstrate a platform based on transitive amorphous indium gallium zinc oxide (aIGZO) pixel elements. Using a lithium based ionic liquid, we demonstrate both potentiation (decrease in device resistance) and depression (increase in device resistance), and propose a 2D platform array that would enable a much higher pixel count via Active Matrix electrowetting.

To evaluate if sedation with propofol during catheter-directed thrombolysis (CDT) in patients with acute submassive pulmonary embolism (PE) affects survival.This single-institution, retrospective study identified 136 patients from 2011-2017 who underwent CDT for acute submassive PE. Patients were grouped based on procedural sedation-propofol versus fentanyl and/or midazolam. Groups were compared for differences in baseline characteristics. Primary endpoint was in-hospital mortality. Logistic regression analysis was performed to evaluate for independent variables predictive of mortality. Propensity-matched analysis was also performed.Propofol was given to 18% (n = 25) of patients, and fentanyl and/or midazolam was given to 82% (n = 111) of patients. Mortality was 28% (n = 7) in the propofol group versus 3% (n = 3) in the fentanyl/midazolam group (P = .0003). Patients receiving propofol had 10.4 times the risk of cardiopulmonary arrest or dying during hospitalization compared with patients receiving fentanyl and/or midazolam (95% confidence interval, 2.9-37.3, P = .0003). The number needed to harm was 4 (95% confidence interval, 2.8-6.8). Logistic regression model analysis including Pulmonary Embolism Severity Index score, right-to-left ventricle diameter ratio and age was not predictive of mortality (P = .19). Adding type of sedation made the model predictive of mortality (P.001). Propensity-matched analysis controlling for baseline differences in age, adjunctive maneuvers, American Society of Anesthesiologists class, and intubation before the procedure revealed that statistical significance between groups remained (P = .01).Sedation with propofol during CDT for acute submassive PE is associated with increased mortality and should be used with caution.

The transradial approach (TRA) has been shown to reduce the morbidity and mortality associated with arterial coronary interventions. Selective internal radiation therapy (SIRT) performed via the TRA can enhance patient comfort, compared with the traditional transfemoral approach (TFA), by allowing immediate ambulation and precluding potential complications associated with the TFA, such as closure device injury or retroperitoneal hematoma. We report our initial experience with and technique for using the TRA for SIRT.Between May 1, 2012, and April 30, 2015, a total of 574 procedures, including planning angiograms (n = 329) and infusions ofTechnical success was achieved in 561 of 574 cases (97.7%). The reasons for crossover to use of the TFA included an RA loop (n = 2), RA occlusion (n = 9), and type D response as determined by use of a Barbeau test (n = 2). Patients had undergone between zero and six previous TRA procedures. The mortality rate at 30 days was 0%. Superficial bruising occurred in 13 of 574 cases (2.3%). A grade 2 hematoma that required a second nonocclusive hemostasis cuff occurred in one case. Transient forearm numbness or pain occurred in two of 574 cases. One patient had a transient convulsive event occur after receiving intraarterial infusion of verapamil. RA occlusion occurred in nine of 574 cases (1.6%).Use of the TRA for SIRT is safe, feasible, and well tolerated and is associated with high rates of technical success and rare complications.

Thickness dependent strain relaxation effects are utilized to study the impact of crystal anisotropy on the optical band gap of epitaxial SnO2 films grown by pulsed laser deposition on (0001)-oriented sapphire substrates. An X-ray diffraction analysis reveals that all films are under tensile biaxial in-plane strain and that strain relaxation occurs with increasing thickness. Variable angle spectroscopic ellipsometry shows that the optical band gap of the SnO2 films continuously increases with increasing film thickness. This increase in the band gap is linearly related to the strain state of the films, which indicates that the main origin of the band gap change is strain relaxation. The experimental observation is in excellent agreement with results from density functional theory for biaxial in-plane strain. This work demonstrates that strain is an effective way to tune the band gap of SnO2 films and suggests that strain engineering is an appealing route to tailor the optical properties of oxide semiconductors.

Purpose To determine if recipients of bone marrow transplants (BMTs) are at increased risk of hemorrhagic complications following transjugular liver biopsy (TJLB). Materials and Methods TJLBs in BMT and non-BMT patients between January 2007 and July 2014 were reviewed. Patient demographic and pre- and postprocedural laboratory data were reviewed. Mean platelet count and International Normalized Ratio were 174,300 × 10 3 /µL ± 107.3 (standard deviation) and 1.2 ± 0.4, respectively, for BMT recipients, compared with 88,100 × 10 3 /µL ± 70.9 and 1.2 ± 0.5, respectively, for non-BMT. Patients in whom hemoglobin level decreased by > 1 g/dL and/or required transfusion within 15 days of TJLB were reviewed to determine the presence of a biopsy-related hemorrhagic complication. Results A total of 1,600 TJLBs in 1,120 patients were analyzed. Of these, 183 TJLBs in 159 BMT recipients and 1,417 TJLBs in 961 patients non-BMT patients were performed. Thirteen TJLBs were complicated by hemorrhage: five in BMT (2.9%) and eight in the non-BMT cohorts (0.6%; P 3 /µL) in all but one patient (8 × 10 3 /µL). BMT recipients had an odds ratio of 4.9 (95% confidence interval, 1.25–17.3) for post-TJLB bleeding/hemorrhage compared with those without BMTs ( P Conclusions TJLB continues to be a safe procedure in the vast majority of patients. However, hemorrhagic complications occurred at a rate of 2.9% in BMT recipients, compared with 0.6% in patients without BMTs, and therefore caution should be exercised when performing TJLB in this group.

Amorphous metal-oxide semiconductors offer the high carrier mobilities and excellent large-area uniformity required for high performance, transparent, flexible electronic devices; however, a critical bottleneck to their widespread implementation is the need to activate these materials at high temperatures which are not compatible with flexible polymer substrates. The highly controllable activation of amorphous indium gallium zinc oxide semiconductor channels using ionic liquid gating at room temperature is reported. Activation is controlled by electric field-induced oxygen migration across the ionic liquid-semiconductor interface. In addition to activation of unannealed devices, it is shown that threshold voltages of a transistor can be linearly tuned between the enhancement and depletion modes. Finally, the first ever example of transparent flexible thin film metal oxide transistor on a polyamide substrate created using this simple technique is demonstrated. This study demonstrates the potential of field-induced activation as a promising alternative to traditional postdeposition thermal annealing which opens the door to wide scale implementation into flexible electronic applications.

The optical band gap of the prototypical semiconducting oxide SnO2 is shown to be continuously controlled through single axis lattice expansion of nanometric films induced by low-energy helium implantation. While traditional epitaxy-induced strain results in Poisson driven multidirectional lattice changes shown to only allow discrete increases in bandgap, we find that a downward shift in the band gap can be linearly dictated as a function of out-of-plane lattice expansion. Our experimental observations closely match density functional theory that demonstrates that uniaxial strain provides a fundamentally different effect on the band structure than traditional epitaxy-induced multiaxes strain effects. Charge density calculations further support these findings and provide evidence that uniaxial strain can be used to drive orbital hybridization inaccessible with traditional strain engineering techniques.

The interventional radiologist has a diverse and expanding role to play in the management and treatment of patients with disorders of the gastrointestinal (GI) system. These patients generally fall into one of two broad categories. The first category includes patients who are unable to tolerate or achieve adequate nutrition by mouth. In these patients, the interventional radiologist may be consulted to obtain percutaneous enteral access so that nutrition or hydration may be administered. The second category includes patients with benign or malignant strictures or obstruction of a hollow viscus, be it the esophagus, stomach, or small or large bowel. In these patients, the goal is to treat the obstruction when possible, or else decompress proximal to the obstruction for palliation of symptoms.

Objective: Hepatitis C virus (HCV) infection is the leading cause of liver disease, and Taiwan has among the highest prevalence of HCV infection in the general population in Northeast Asia, estimated at between 2% and 4%. The aim of this study was to estimate the number of patients living with chronic HCV infection in Taiwan and quantify the expected numbers in each of the five Metavir fibrosis stages. Methods: We applied a back-projection approach, using observed hepatocellular carcinoma incidence between 1979 and 2008 and a smoothed Expectation-Maximization algorithm to maximize a Poisson likelihood to estimate the previous incidence of HCV infection. The algorithm was coded in Excel and combined with the MOdelling the NAtural histoRy and Cost-effectiveness of Hepatitis model (a hepatitis C natural history markov model) to predict the past and future numbers in each Metavir fibrosis stage. Results: Incident cases were predicted to have peaked in 1972 at 56,634 annually, with the prevalence peaking in 1986 at 763,737 infections and falling to 578,203 infections in 2012. It was estimated that in 2012, 127,795 (23.0%), 105,545 (19.0%), 81,211 (14.6%), 123,939 (22.3%), and 116,823 (21.1%) subjects were in fibrosis stages F0, F1, F2, F3, and F4, respectively. Discussion: Our study provides HCV infection prevalence estimates, stratified by Metavir fibrosis stage, in Taiwan for 2012. This has potential implications for budget planning, particularly with the availability of emerging therapies because fibrosis stage is predictive of both rapid and sustained virological response; therefore, planning expected treatment response in a given population could be enhanced with this additional information.

Purpose: To review the safety of hepatic radioembolization (RE) in patients with high (>= 10%) hepatopulmonary shunt fraction (HPSF) using various prophylactic techniques. Materials and Methods: A review was conducted of 409 patients who underwent technetium 99m-labeled macroaggregated albumin scintigraphy before planned RE. Estimated pulmonary absorbed radiation doses based on scintigraphy and hepatic administered activity were calculated. Outcomes from dose reductions and adjunctive catheter-based prophylactic techniques used to reduce lung exposure were assessed. Results: There were 80 patients with HPSF >= 10% who received RE treatment (41 resin microspheres for metastases, 39 glass microspheres for hepatocellular carcinoma). Resin microspheres were used in 17 patients according to consensus guideline-recommended dose reduction; 38 patients received no dose reduction because the expected lung dose was

Background Evaluation of the headache patient in the outpatient clinic and emergency department (ED) has different focuses and goals. The focus of this paper is to review the evaluation of patients in both settings with mention of evaluation in the pediatric and pregnant patient population. The patient's history should drive the practitioner's decision and evaluation choices. We review recommendations made by the American Board of Internal Medicine and American Headache Society through the Choosing Wisely Campaign, which has an emphasis on choosing the right imaging modality for the clinical situation and elimination/prevention of medication overuse headache, as well as the US Headache Consortium guidelines for migraine headache. We will also review focusing on ED evaluation of the pediatric patient and pregnant patient presenting with headache. Conclusion At the end of the review we hope to have provided you with a framework to think about the headache patient and what is the appropriate test in the given clinical setting in order to ensure that the patient gets the right diagnosis and is set on a path to the appropriate management plan.

Purpose To review the safety and effectiveness of direct intrahepatic portocaval shunt (DIPS) creation with variceal embolization for acute variceal hemorrhage after a failed transjugular intrahepatic portosystemic shunt (TIPS) creation attempt or in patients with prohibitive anatomy. Materials and Methods Transjugular intrahepatic portosystemic shunt and DIPS procedures performed for variceal hemorrhage between January 2008 and July 2014 were reviewed. The default procedure was TIPS creation, with DIPS creation reserved for patients with unfavorable anatomy or who had technically unsuccessful TIPS creation. Thirteen patients underwent DIPS creation (mean age, 60 y ± 12; Child–Pugh class A/B/C, 8%/62%/30%; Model for End-stage Liver Disease score, 15 ± 5; range, 8–26) and 117 underwent TIPS creation. Four patients underwent a TIPS attempt and were converted to DIPS creation upon technical failure; 9 were treated primarily with DIPS creation because of preprocedural imaging revealing unfavorable anatomy (intrahepatic portal thrombosis, n = 2; venous distortion from prior hepatic resections, n = 2; severely angulated hepatic veins, n = 5). Results Direct intrahepatic portocaval shunt creation with variceal embolization (six gastric or esophageal; seven stomal, duodenal, or rectal) was successful in all patients; 11 also had concomitant variceal sclerotherapy. Mean DIPS procedure time was less than 2 hours. There was 1 major procedural complication. During a mean follow-up of 13.0 months ± 15.5, 1 patient developed DIPS thrombosis and recurrent hemorrhage; 1 patient underwent successful transplantation. Two deaths were observed within 30 days, neither associated with recurrent hemorrhage. Conclusions Direct intrahepatic portocaval shunt creation appears to be a safe, expedient, and effective treatment for patients with acute variceal hemorrhage who are poor anatomic candidates for TIPS creation or who have undergone unsuccessful TIPS creation attempts.

The idiopathic interstitial pneumonias (IIPs) are a group of diffuse lung diseases that share many similar radiologic and pathologic features. According to the revised 2013 American Thoracic Society-European Respiratory Society classification system, these entities are now divided into major IIPs (idiopathic pulmonary fibrosis, idiopathic nonspecific interstitial pneumonia, respiratory bronchiolitis-associated interstitial lung disease, desquamative interstitial pneumonia, cryptogenic organizing pneumonia, and acute interstitial pneumonia), rare IIPs (idiopathic lymphoid interstitial pneumonia, idiopathic pleuroparenchymal fibroelastosis), and unclassifiable idiopathic interstitial pneumonias. Some of the encountered radiologic and histologic patterns can also be seen in the setting of other disorders, which makes them a diagnostic challenge. As such, the accurate classification of IIPs remains complex and is best approached through a collaboration among clinicians, radiologists, and pathologists, as the treatment and prognosis of these conditions vary greatly.

Atomic resolution imaging and spectroscopy suffers from inherently low signal to noise ratios often prohibiting the interpretation of single pixels or spectra. We introduce local low rank (LLR) denoising as tool for efficient noise removal in scanning transmission electron microscopy (STEM) images and electron energy-loss (EEL) spectrum images. LLR denoising utilizes tensor decomposition techniques, in particular the multilinear singular value decomposition (MLSVD), to achieve a denoising in a general setting largely independent of the signal features and data dimension, by assuming that the signal of interest is of low rank in segments of appropriately chosen size. When applied to STEM images of graphene, LLR denoising suppresses statistical noise while retaining fine image features such as scan row-wise distortions, possibly related to rippling of the graphene sheet and consequent motion of atoms. When applied to EEL spectra, LLR denoising reveals fine structures distinguishing different lattice sites in the spinel system CoFe

The purpose of this study is to evaluate the effectiveness of electromagnetic tracking in assisting CT-guided liver biopsies.This was a single-center prospective randomized controlled trial comparing nonfluoroscopic CT-guided liver biopsy using an advance-and-scan technique with and without electromagnetic tracking. Fifty patients with a liver lesion referred for biopsy (women, 52%; mean age, 59.7 years; mean lesion size, 3.6 cm) were enrolled in the study and were randomly assigned to either arm. The primary and secondary objectives were to assess and quantify differences in the number of intraprocedural scans, cumulative effective radiation dose, number of needle manipulations, and procedure time from skin-stick to the target lesion with and without assistance.Electromagnetic tracking significantly decreased the number of scans, effective radiation dose, number of manipulations per procedure, and time from skin-stick to the target lesion. The ratio of the number of scans (electromagnetic tracking to control) was 0.55 (95% CI, 0.42-0.73; p0.0001). The mean difference in effective radiation dose (electromagnetic tracking-control) was -4.7 mSv (95% CI, -7.01 to -2.44 mSv; p=0.0001), and the median difference was -5.1 mSv (95% CI, -7.01 to -3.56 mSv; p0.0001). The ratio of the number of manipulations (electromagnetic tracking to control) was 0.36 (95% CI, 0.24-0.54; p0.0001). The mean difference for the time from skin-stick to the target lesion was -247.6 seconds (95% CI, -394.34 to -100.83 seconds; p=0.0014) and the median difference was -253.0 seconds (95% CI, -325.00 to -124.00 seconds; p=0.0001).Electromagnetic tracking assistance has the potential to decrease the number of intraprocedural CT scans and needle manipulations and to reduce patient radiation dose during CT-guided liver biopsy.