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Treatment algorithms

W Abel Wright, Jack M Gorman, Melissa Odorzynski, Mark J Peterson, Carol Clayton
BACKGROUND: Patients receiving psychiatric services at community mental health centers (CMHCs) are often prescribed medication that is critical to the treatment of behavioral health conditions, including schizophrenia, bipolar disorder, anxiety, and depression. Previous studies have shown correlation between rates of medication adherence and risk of hospitalization, but potential differences in medication adherence and other outcomes for patients of CMHCs by pharmacy type have not been widely studied...
November 2016: Journal of Managed Care & Specialty Pharmacy
Andrew F Auld, Tefera Agizew, Sherri Pals, Alyssa Finlay, Ndwapi Ndwapi, Rosanna Boyd, Heather Alexander, Anikie Mathoma, Joyce Basotli, Sambayawo Gwebe-Nyirenda, James Shepherd, Tedd V Ellerbrock, Anand Date
BACKGROUND: In 2012, as a pilot for Botswana's national Xpert MTB/RIF (Xpert) rollout plans, intensified tuberculosis (TB) case finding (ICF) activities were strengthened at 22 HIV treatment clinics prior to phased activation of 13 Xpert instruments. Together, the strengthened ICF intervention and Xpert activation are referred to as the "Xpert package". METHODS: The evaluation, called the Xpert Package Rollout Evaluation using a Stepped-wedge design (XPRES), has two key objectives: (1) to compare sensitivity of microscopy-based and Xpert-based pulmonary TB diagnostic algorithms in diagnosing sputum culture-positive TB; and (2) to evaluate impact of the "Xpert package" on all-cause, 6-month, adult antiretroviral therapy (ART) mortality...
October 26, 2016: BMC Infectious Diseases
Antonella Fogliata, Francesca Lobefalo, Giacomo Reggiori, Antonella Stravato, Stefano Tomatis, Marta Scorsetti, Luca Cozzi
PURPOSE: Small field measurements are challenging, due to the physical characteristics coming from the lack of charged particle equilibrium, the partial occlusion of the finite radiation source, and to the detector response. These characteristics can be modeled in the dose calculations in the treatment planning systems. Aim of the present work is to evaluate the MU calculation accuracy for small fields, defined by jaw or MLC, for anisotropic analytical algorithm (AAA) and Acuros XB algorithms, relative to output measurements on the beam central axis...
October 2016: Medical Physics
A Neubert, Z Yang, C Engstrom, Y Xia, M W Strudwick, S S Chandra, J Fripp, S Crozier
PURPOSE: Magnetic resonance (MR) imaging plays a key role in investigating early degenerative disorders and traumatic injuries of the glenohumeral cartilages. Subtle morphometric and biochemical changes of potential relevance to clinical diagnosis, treatment planning, and evaluation can be assessed from measurements derived from in vivo MR segmentation of the cartilages. However, segmentation of the glenohumeral cartilages, using approaches spanning manual to automated methods, is technically challenging, due to their thin, curved structure and overlapping intensities of surrounding tissues...
October 2016: Medical Physics
Dan Nguyen, David Thomas, Minsong Cao, Daniel O'Connor, James Lamb, Ke Sheng
PURPOSE: Magnetic resonance imaging (MRI)-guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target and critical organ tracking. To increase delivery efficiency, the system uses three Co-60 sources at 120° apart, allowing up to 600 cGy combined dose rate at isocenter. Despite the potential tripling in output, creating a delivery plan that uses all three sources is considerably unintuitive. Here, the authors computerize the triplet orientation optimization using column generation, an approach that was demonstrated effective in integrated beam orientation and fluence optimization for noncoplanar therapies...
October 2016: Medical Physics
Qiang Liu, Jian Liang, Carl W Stanhope, Di Yan
PURPOSE: Inaccurate density information may introduce dose calculation errors when inhomogeneity correction is applied. The aim of the present study was to examine the effect of density variation on photon dose calculation accuracy using the convolution/superposition (CS) algorithm with the focus on newer treatment technologies including intensity modulated radiotherapy, volumetric modulated arc radiotherapy, and stereotactic body radiotherapy (SBRT). METHODS: Calculations were first performed using simple inhomogeneity phantoms in order to determine clinically relevant tolerance levels for different tissue types...
October 2016: Medical Physics
Christopher Kurz, Florian Kamp, Yang-Kyun Park, Christoph Zöllner, Simon Rit, David Hansen, Mark Podesta, Gregory C Sharp, Minglun Li, Michael Reiner, Jan Hofmaier, Sebastian Neppl, Christian Thieke, Reinoud Nijhuis, Ute Ganswindt, Claus Belka, Brian A Winey, Katia Parodi, Guillaume Landry
PURPOSE: This work aims at investigating intensity corrected cone-beam x-ray computed tomography (CBCT) images for accurate dose calculation in adaptive intensity modulated proton therapy (IMPT) for prostate and head and neck (H&N) cancer. A deformable image registration (DIR)-based method and a scatter correction approach using the image data obtained from DIR as prior are characterized and compared on the basis of the same clinical patient cohort for the first time. METHODS: Planning CT (pCT) and daily CBCT data (reconstructed images and measured projections) of four H&N and four prostate cancer patients have been considered in this study...
October 2016: Medical Physics
Bin Liang, Yongbao Li, Bo Liu, Fugen Zhou, Shouping Xu, Qiuwen Wu
PURPOSE: CyberKnife system is initially equipped with fixed circular cones for stereotactic radiosurgery. Two dose calculation algorithms, Ray-Tracing and Monte Carlo, are available in the supplied treatment planning system. A multileaf collimator system was recently introduced in the latest generation of system, capable of arbitrarily shaped treatment field. The purpose of this study is to develop a model based dose calculation algorithm to better handle the lateral scatter in an irregularly shaped small field for the CyberKnife system...
October 2016: Medical Physics
Seyoun Park, Todd McNutt, William Plishker, Harry Quon, John Wong, Raj Shekhar, Junghoon Lee
PURPOSE: Accurate tracking of anatomical changes and computation of actually delivered dose to the patient are critical for successful adaptive radiation therapy (ART). Additionally, efficient data management and fast processing are practically important for the adoption in clinic as ART involves a large amount of image and treatment data. The purpose of this study was to develop an accurate and efficient Software platform for CUmulative Dose Assessment (scuda) that can be seamlessly integrated into the clinical workflow...
October 2016: Medical Physics
Svenja Ipsen, Ralf Bruder, Rick O'Brien, Paul J Keall, Achim Schweikard, Per R Poulsen
PURPOSE: With the trend in radiotherapy moving toward dose escalation and hypofractionation, the need for highly accurate targeting increases. While MLC tracking is already being successfully used for motion compensation of moving targets in the prostate, current real-time target localization methods rely on repeated x-ray imaging and implanted fiducial markers or electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging can yield volumetric data in real-time (3D + time = 4D) without ionizing radiation...
October 2016: Medical Physics
Troy Long, Mingli Chen, Steve Jiang, Weiguo Lu
PURPOSE: Conventional step-and-shoot intensity modulated radiation therapy leaf sequencing methods, where a nonhomogeneous fluence map is converted to a set of apertures and associated intensities, assume that target fluence is stratified into a fixed number of discrete levels and/or aperture leaf positions are restricted to a discrete set of locations. These assumptions induce a deviation from the planned fluence map and/or reduce the feasible region of potential plans, respectively...
October 2016: Medical Physics
Olof Westin, Katarina Nilsson Helander, Karin Grävare Silbernagel, Michael Möller, Peter Kälebo, Jón Karlsson
BACKGROUND: The optimal treatment for acute Achilles tendon ruptures is still an ongoing debate. Acute ultrasonography (US) investigation to measure the diastasis between the tendon ends has previously been used to classify acute Achilles tendon ruptures; however, no study has used US to predict reruptures and functional outcomes. PURPOSE: To investigate whether acute US can be used to predict the risk of reruptures and outcomes after treatment of an acute Achilles tendon rupture...
October 2016: Orthopaedic Journal of Sports Medicine
Diogo C Haussen, Renato A C Oliveira, Vikas Patel, Raul G Nogueira
BACKGROUND AND PURPOSE: Extensive brainstem diffusion-weighted imaging (DWI) hyperintensity has been associated with poor outcomes. We aim at documenting a series of patients with extensive DWI pontine lesions who achieved independence following endovascular therapy and aggressive medical therapy in the setting of posterior circulation basilar artery occlusion (BAO). METHODS: This is a retrospective endovascular database review of a single-operator experience over a 9-year period for patients with (1) complete BAO, (2) extensive bilateral pontine DWI changes and (3) 90-day modified Rankin scale 0-2...
September 2016: Interventional Neurology
Thomas Peach, Katerina Spranger, Yiannis Ventikos
Bifurcation aneurysms account for a large fraction of cerebral aneurysms and often present morphologies that render traditional endovascular treatments, such as coiling, challenging and problematic. Flow-diverter stents offer a potentially elegant treatment option for such aneurysms, but clinical use of these devices remains controversial. Specifically, the deployment of a flow-diverter device in a bifurcation entails jailing one or more potentially vital vessels with a low-porosity mesh designed to restrict the flow...
October 25, 2016: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
Alice Kizny Gordon, Christopher McIver, Minhee Kim, Dedee F Murrell, Peter Taylor
The dermatophytoses are the most common superficial fungal infections worldwide. Clinical diagnosis is not reliable as there are many differentials, and laboratory diagnosis is required to gain access to treatment in more severe disease. Traditional diagnostic methods are limited by suboptimal sensitivity, specificity and prolonged turnaround times. Molecular methods are being used increasingly in the diagnostic algorithm in the clinical microbiology laboratory. The aim of this study was to evaluate a real-time polymerase chain reaction (RT-PCR) targeting the chitin synthase 1 gene (CHS1) of dermatophytes for analytical specificity, and to assess its clinical application by comparing it to the current methods of microscopy and culture...
October 22, 2016: Pathology
G K Nikolopoulos, A Katsoulidou, M Kantzanou, C Rokka, C Tsiara, V Sypsa, D Paraskevis, M Psichogiou, S Friedman, A Hatzakis
This analysis assessed the utility of the limiting antigen avidity assay (LAg). Samples of people who inject drugs (PWID) in Greece with documented duration of HIV-1 infection were tested by LAg. A LAg-normalized optical density (ODn) ⩽1·5 corresponds to a recency window period of 130 days. The proportion true recent (PTR) and proportion false recent (PFR) were estimated in 28 seroconverters and in 366 samples collected >6 months after HIV diagnosis, respectively. The association between LAg ODn and HIV RNA level was evaluated in 232 persons...
October 26, 2016: Epidemiology and Infection
Jaber Zafari, Fatemeh Javani Jouni, Ali Ahmadvand, Parviz Abdolmaleki, Malihe Soodi, Rezvan Zendehdel
A model was set up to predict the differentiation patterns based on the data extracted from FTIR spectroscopy. For this reason, bone marrow stem cells (BMSCs) were differentiated to primordial germ cells (PGCs). Changes in cellular macromolecules in the time of 0, 24, 48, 72, and 96h of differentiation, as different steps of the differentiation procedure were investigated by using FTIR spectroscopy. Also, the expression of pluripotency (Oct-4, Nanog and c-Myc) and specific genes (Mvh, Stella and Fragilis) were investigated by real-time PCR...
October 17, 2016: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Sebastian Schneeweiss, Wesley Eddings, Robert J Glynn, Elisabetta Patorno, Jeremy Rassen, Jessica M Franklin
BACKGROUND: Data-adaptive approaches to confounding adjustment may improve performance beyond expert knowledge when analyzing electronic healthcare databases and have additional practical advantages for analyzing multiple databases in rapid cycles. Improvements seemed possible if outcome predictors were reliably identified empirically and adjusted. METHODS: In five cohort studies from diverse healthcare databases, we implemented a base-case high-dimensional propensity score algorithm with propensity score decile-adjusted outcome models to estimate treatment effects among prescription drug initiators...
October 21, 2016: Epidemiology
Shekhar S Chandra, Jason A Dowling, Peter B Greer, Jarad Martin, Chris Wratten, Peter Pichler, Jurgen Fripp, Stuart Crozier
Active shape models (ASMs) have proved successful in automatic segmentation by using shape and appearance priors in a number of areas such as prostate segmentation, where accurate contouring is important in treatment planning for prostate cancer. The ASM approach however, is heavily reliant on a good initialisation for achieving high segmentation quality. This initialisation often requires algorithms with high computational complexity, such as three dimensional (3D) image registration. In this work, we present a fast, self-initialised ASM approach that simultaneously fits multiple objects hierarchically controlled by spatially weighted shape learning...
November 21, 2016: Physics in Medicine and Biology
S Ipsen, O Blanck, N J Lowther, G P Liney, R Rai, F Bode, J Dunst, A Schweikard, P J Keall
Radiosurgery to the pulmonary vein antrum in the left atrium (LA) has recently been proposed for non-invasive treatment of atrial fibrillation (AF). Precise real-time target localization during treatment is necessary due to complex respiratory and cardiac motion and high radiation doses. To determine the 3D position of the LA for motion compensation during radiosurgery, a tracking method based on orthogonal real-time MRI planes was developed for AF treatments with an MRI-guided radiotherapy system. Four healthy volunteers underwent cardiac MRI of the LA...
November 21, 2016: Physics in Medicine and Biology
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