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INTRODUCTION: There is a paucity of data in the literature regarding the diagnostic accuracy of perfusion (Q)-only studies in the absence of ventilation images. This study aims to assess the diagnostic accuracy of Q-only imaging in the pandemic era. METHODS: Patients who underwent Q-only imaging for pulmonary embolism between March 2020 and February 2021 were analyzed. Patients who underwent lung quantification analysis were excluded. Q-only test results were reported as per modified PIOPED II criteria and single positron emission tomography/computed tomography (SPECT/CT) imaging was performed as needed. Patients were considered concordant or discordant by correlating the Q-only results with CT angiogram (CTA) or clinical diagnosis made through chart review. The diagnostic accuracy was calculated after excluding intermediate probability and nondiagnostic studies. RESULTS: Four hundred and thirty-four patients were identified. One hundred and twenty-eight patients (29.4%) underwent ultrasound Doppler, 37 patients (8.5%) underwent CTA, and 16 patients (3.6%) underwent both. After excluding patients with intermediate probability or nondiagnostic studies and who did not have follow-up (a total of 87 patients [20%]), 347 patients were enrolled in the final analysis. The combined planar and SPECT/CT sensitivity and specificity were 85.4% (72.2%–93.9% confidence interval [CI]) and 98.7% (96.9%–98.6% CI), respectively. The positive predictive value (PPV) of the Q-only imaging was 89.1% (77.3%–95.1% CI) and the negative predictive value (NPV) was 98.2% (96.4%–99% CI). The sensitivity with SPECT/CT reached 100% (CI: 71.5%–100%) with a specificity of 92.3% (CI: 64%–99.8%). The PPV was 85.7% (CI: 62.1%–95.6%) and the NPV was 100%. CONCLUSION: Q-only imaging provides clinically acceptable results. The sensitivity of the Q-only scan is increased when coupled with SPECT/CT.

Abstract Background To compare image quality, lesion detection and patient comfort of 3T prostate MRI using a combined rigid two-channel phased-array endorectal coil and an external phased-array coil (ERC-PAC) compared to external PAC acquisition in the same patients. Methods Thirty three men (mean age 65.3y) with suspected (n = 15) or biopsy-proven prostate cancer (PCa, n = 18) were prospectively enrolled in this exploratory study. 3T prostate MRI including T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) was performed using an ERC-PAC versus PAC alone, in random order. Image quality, lesion detection and characterization (biparametric PI-RADSv2.1) were evaluated by 2 independent observers. Estimated signal-to-noise ratio (eSNR) was measured in identified lesions and the peripheral zone (PZ). Patient comfort was assessed using a questionnaire. Data were compared between sequences and acquisitions. Inter/intra-observer agreement for PI-RADS scores was evaluated. Results Twenty four prostate lesions (22 PCa) were identified in 20/33 men. Superior image quality was found for ERC-PAC compared to PAC for T2WI for one observer (Obs.1, p

In this paper, we present a novel approach that addresses the problem of large-scale network topology design and routing. There are research works that used exact methodologies based on Integer Linear Programming (ILP) models to develop potential solutions for this problem. However, this problem is computationally NP-hard, thus solving it is hugely demanding on computational power for large-scale networks, and in many cases, it is not even possible to generate a solution with a reasonable optimality gap. This paper presents a hybrid algorithm based on the Genetic Algorithm with efficiently designed genetic operators. This algorithm aims to design the topology of large-scale networks and generate a routing configuration for a set of predefined traffic demands on the networks while keeping the total cost of design and routing at a minimum. The results have been compared to an exact ILP model, a relaxed ILP model, and a customized GA as benchmarks for validation purposes. These comparisons showed that the proposed algorithm significantly outperforms the ILP solutions in all of the large-scale network configurations that were used as case studies.

This pilot study investigates the impact of active design (AD) strategies on physical activity (PA) among adults living in two Leadership in Energy and Environmental Design (LEED) certified affordable housing developments in the South Bronx, New York. One building incorporates LEED Innovation in Design (ID) Credit: Design for Health through Increased Physical Activity. Tenants in an affordable housing building (AH) incorporating active design strategies completed PA self-assessments at their lease signing and one year later in 2015. Trained research assistants obtained body measurements. Residents of neighboring non-AD affordable housing (MCV) served as a comparison. Thirty four adults were recruited from AH and 29 from MCV, retention was 56% (n = 19) and 52% (n = 15) respectively at one year. The two groups' body mass index (BMI) and high-risk waist-to-hip ratio (WHR) were not statistically significantly different when analyzed as continuous variables, although BMI category had a greater decline at AH than at MCV (p = 0.054). There was a 31.5% increase in AH participants meeting MPA requirements and a statistically significant improvement in females (p = 0.031); while there was no change in the MCV participants overall or when stratified by gender. AH participants were significantly more likely to have reported increased stair use and less likely to have reported no change or decreased stair use than participants from MCV participants (p = 0.033). Housing has a role in individual health outcomes and behavior change, broad adoption of active design strategies in affordable housing is warranted to improve physical activity measures. Keywords: Active design, Physical activity, Built environment, Affordable housing

Category: Midfoot/Forefoot Introduction/Purpose: Affecting an estimated 1 in 40 adults over the age of 50, hallux limitus is among the leading arthridites of the foot and ankle, with growing incidence reflecting an aging population. Despite its prevalence and disease burden, treatment of the condition remains equivocal. Many patients fail initial conservative measures (e.g., NSAIDs, physical therapy, corticosteroid injections) and may be averse to or ineligible for surgery. For others, there exists controversy surrounding the indications and outcomes of various surgical procedures. As such, there is demand for new means of non-operative management. The present study sought to examine the impact of a novel in-shoe device, the Hallux Limitus Forefoot Orthosis (HLFO), on plantar pressure, foot function, and pain in patients with hallux limitus. Methods: Twenty adult patients with symptomatic hallux limitus were recruited for the study. Diagnosis of hallux limitus was confirmed via physical exam and plain radiography. Patients with diabetes, pre-diabetes, peripheral artery disease (Ankle Brachial Index < 0.70), neuropathy (positive Semmes-Weinstein monofilament test), or lower extremity wounds were excluded. At baseline, participants completed the Foot Function Index (FFI) and reported foot pain on a visual analogue scale (VAS) from 0 to 10. Heat map profiles were also generated using a plantar pressure sensor. The HLFO was then issued to participants, who were instructed to wear it in standard athletic shoes. Participants were contacted by phone after 2 weeks for feedback and to inquire about any adverse events. One participant was lost to follow-up. At 4 weeks, participants returned, and FFI, VAS pain, and plantar pressure measurements were repeated with the HLFO on. Results: Mean FFI decreased significantly from 43.0% (± 18.8%) to 11.0% (± 9.8%) following use of the HLFO, t(18) = 6.78, p

Falls are common among older adults. However, not much is known about the prevalence of falls among older patients with cancer. In 2015, older patients with cancer referred to Geriatrics service for preoperative evaluation were assessed for fall history, basic and instrumental activities of daily living (ADL and IADL), KPS, and use of assistive device. Of 806 patients, 215 (26.7%) patients reported fall. Incidence of last fall inside and outside home was 54.4% and 45.5%, respectively. Among patients with no falls, 33.6% had KPS ≤ 80 compared to 59.6% with one-time fall and 60.7% with multiple falls (p

In modeling communication networks for simulation of survivability schemes, one goal is often to implement these schemes across varying degrees of nodal connectivity to get unbiased performance results. Abstractions of real networks, simple random networks, and families of networks are the most common categories of these sample networks. This paper looks at how using the network family concept provides a solid unbiased foundation to compare different network protection models. The network family provides an advantage over random networks by requiring one solution per average nodal degree, as opposed to having to solve many, which could take a significant amount of time. Also, because the network family looks at a protection scheme across a variety of average nodal connectivities, a clearer picture of the scheme’s performance is gained compared to just running the simulation on a single network or select few networks.

p-cycle networks have attracted a considerable interest in the network survivability literature in recent years. However, most of the existing work assumes a known network topology upon which to apply p-cycle restoration. In the present work, we develop an incremental topology optimization ILP for p-cycle network design, where a known topology can be amended with new fibre links selected from a set of eligible spans. The ILP proves to be relatively easy to solve for small test case instances but becomes computationally intensive on larger networks. We then follow with a relaxation-based decomposition approach to overcome this challenge. The decomposition approach significantly reduces computational complexity of the problem, allowing the ILP to be solved in reasonable time with no statistically significant impact on solution optimality.

Objective. The study objective was to examine relationships between different body size measurements and asthma in ethnic minority children. Methods. We used data from a community-based study of 505 children aged 6-to-8 years old to study the association of percent body fat, fat distribution, and BMI percentile with asthma diagnosis. Poisson regression models were used to compute prevalence ratios (PRs) for sex-specific quintiles of the body fat measures on the main outcome of asthma. Results. When comparing the highest quintile of each body fat measure to the combined lowest two quintiles, higher body mass index percentile, percent body fat, and waist circumference all were associated with a higher likelihood of physician-diagnosed asthma (PR = 1.63 (95% CI 1.12–2.39), 1.50 (95% CI 1.02–2.21), and 1.56 (95% CI 1.04–2.34), resp.). Conclusions. This study found a significant association between increased body size and asthma diagnosis, regardless of the measurement examined.

Our aging population has exacerbated strong and divergent trends between health human resource supply and demand. One way to mitigate future inequities is through the adoption of health information technology (HIT). Our previous research showed a number of risks and mitigating factors which affected HIT implementation success. We confirmed these findings through semistructured interviews with nine Alberta clinics. Sociotechnical factors significantly affected physicians' implementation success. Physicians reported that the time constraints limited their willingness to investigate, procure, and implement an EMR. The combination of antiquated exam room design, complex HIT user interfaces, insufficient physician computer skills, and the urgency in patient encounters precipitated by a fee-for-service remuneration model and long waitlists compromised the quantity, if not the quality, of the information exchange. Alternative remuneration and access to services plans might be considered to drive prudent behavior during physician office system implementation.

Abstract In an optical transport network distinct logical groups of lightwave channels between neighboring OXC nodes (called spans) may sometimes be realized over a common physical resource such as a duct or conduit, and hence share a common cause of failure. This is closely related to the concept of shared risk on individual channels or links, called SRLGs, which is relevant to pre-planned path protection schemes with shared capacity on backup paths. But when considering span-restorable networks, shared risk over logical spans (not individual channels) is the corresponding issue of concern. This work considers several aspect of how such shared-risk span groups (SRSG) affect the protection capacity design and other aspects of span-restorable mesh networks. We provide a model for capacity planning any span-restorable network in the presence of a known set of such shared-risk spans and study the relationship between capacity requirements and the number and placement of such situations. This provides guidelines as to how many SRSGs can be sustained before the capacity penalty becomes severe and methods to diagnose which of them are the most limiting to overall protection efficiency. One finding of interest is that if a given percentage of all possible dual-failure combinations incident to a common node are allowed for in the design, then nearly the same percentage of other dual-span failure combinations (any two spans in the network) will also be restorable. We also show that designing a network to withstand even a small number of multi-span co-incident spared-risk span groups will yield a significant improvement in overall dual-failure restorability and hence also in network availability. [ABSTRACT FROM AUTHOR]

Low dose rate (LDR) brachytherapy is a minimally invasive form of radiation therapy, used to treat prostate cancer, and it involves permanent implantation of radioactive sources (seeds) inside of the prostate gland. Treatment planning in brachytherapy involves a decision making process for the placement of the sources in order to deliver an effective dose of radiation to cancerous tissue in the prostate while sparing the surrounding healthy tissue. Such a decision making process can be modeled as a mixed-integer linear programming (MILP) problem. In this paper, we introduce a novel MILP optimization model framework for interstitial LDR prostate brachytherapy designed to explicitly mimic the qualities of treatment plans produced manually by expert planners. Our approach involves incorporating a unique set of clinically important constraints, called spatial constraints, into the optimization model. Computational results for an initial model reflecting clinical practice at our cancer center show that the treatment plans produced largely capture the spatial and dosimetric characteristics of manual plans created by expert planners. [ABSTRACT FROM AUTHOR]