Prescription Plan Research Articles

Ultrasound assessment of gastric emptying time in preterm infants: A prospective observational study.

In paediatric anaesthesia, pre-operative fasting should be short to prevent discomfort, hunger, thirst and metabolic disorders. Current European guidelines recommend pre-operative fasting times of 4 h for breast milk and 6 h for formula milk in infants, whereas some national guidelines allow both until 4 h before anaesthesia. We evaluated the gastric emptying times of preterm infants after breast milk and formula milk, hypothesising that the mean gastric emptying time would be less than 4 h. A prospective, observational, noninterventional cohort study. Neonatal ICU of a university hospital from August to September 2017. Twenty-two infants with a postmenstrual mean ± SD (range) age of 35 ± 2 (32 to 40) weeks were included. Based on their prescription plan, 10 infants received breast milk and 12 received formula milk with a total volume of 50 ± 16 (24 to 70) ml. Gastric emptying was examined by sonographic measurements of the gastric antral area (GAA) before (FT0) and hourly after breast milk or formula milk feeding (FT1 to FT3). Estimated gastric emptying time after enteral feeding with breast milk and formula milk in preterm infants. The GAA of the preterm infants initially increased and subsequently decreased after feeding. GAA correlated significantly with fasting time (r = -0.53, P < 0.0001). At FT3 [199 ± 16 (175 to 225) min], GAA was 0.57 (0.42 to 0.91) cm and showed no difference compared with FT0. Using a linear regression model, the calculated mean gastric emptying time was 218 min. The study shows that the mean gastric emptying time after enteral feeding with breast milk and formula milk is less than 4 h in preterm infants. These results support our current national fasting regimen of 4 h for any milk composition in infants before anaesthesia. German registry of clinical studies (DRKS-ID: DRKS 00013893).

Impact of TPS calculation algorithms on dose delivered to the patient in proton therapy treatments

To estimate the impact of dose calculation approaches adopted in different treatment planning systems (TPSs) on proton therapy dose delivered with pencil beam scanning (PBS).Treatment plans for six regular volumes in water and 15 clinical cases were optimized with Syngo-VC13 and exported for forward recalculation with Raystation-V7.0 pencil beam (RS-PBA) and Monte Carlo (RS-MC) algorithms and with the independent Fluka-MC engine. To verify clinical consistency between the two TPS dosimetric outcomes, the average percentage variations of clinical target volume (CTV) D98%, D50% and D2%, adopted for plan prescription and evaluation, were considered. Ionization chamber measurements served as a further reference for comparison in homogeneous conditions. CTV dose volume histogram (DVH) analysis and gamma evaluation with 3 mm—3% agreement criteria quantified the dose deviation of TPS calculation algorithms, in heterogeneous conditions, against the Fluka-MC code.CTV D50%, representing the plan dose prescription goal, was higher on average over H&N cases of (3.9 ± 0.9)% and (2.3 ± 0.6)% as calculated with RS-PBA and RS-MC, respectively, compared to Syngo. For tumors located in the pelvis district, average D50% variations of (1.6 ± 0.7)% and (1.2 ± 0.7)% were found. Syngo underestimated target near maximum doses with respect to all computation systems. Calculation accuracy in heterogeneous conditions of RS-PBA H&N plans resulted poor when a range shifter was required. Target DVH and γ-analysis showed excellent agreement between RS-MC and Fluka-MC, with γ-pass rates >98% for all patient groups.Different TPS dose calculation approaches mainly affected dose delivered in H&N proton treatments, while minor deviations were found for pelvic tumors. RS-MC proved to be the most accurate TPS dose calculation algorithm when compared to an independent MC simulation code.

On academic writing

This essay examines the literature related to the craft of academic writing, with a particular focus on four academic writing how-to books. Three of the books present prescriptive plans for becoming a productive academic writer, while the fourth is based on a qualitative study of 100 successful academic writers. The article examines the advice within these texts, comparing and contrasting the recommendations of each, and then discusses the applicability of the works to the profession of librarianship.

Impact of dosing frequency (once daily or twice daily) on patient adherence to oral targeted therapies for hematologic malignancies: a retrospective cohort study among managed care enrollees.

PurposeExisting studies evaluating patient adherence to oral targeted therapies such as tyrosine kinase inhibitors focus on small populations with single malignancies. This study evaluated patterns of use of oral agents in a larger population across multiple hematologic malignancies.MethodsAdult patients diagnosed with a hematologic malignancy and prescribed oral targeted therapy between 2011 and 2016 (N = 18,976) were identified from the MarketScan Commercial Claims and Encounters, and Medicare Supplemental databases. Eligible patients were enrolled in monthly prescription plans 6 months before and 12 months after the index date (date of first prescription claim; n = 2442). Multivariable logistic regressions were used to determine predictors of adherence using the medication possession ratio (MPR) and persistence through prescription refill gaps.ResultsThe overall median adherence was 0.9 (MPR ≥ 80%) and was comparable between once-daily (QD) and twice-daily (BID) groups. Overall, 59% of patients were persistent at 12 months. Patients on QD and BID products did not have any significant differences in adherence (fixed-interval MPR, odds ratio 0.94; 95% confidence interval (CI), 0.75–1.18) or persistence (odds ratio 0.93; 95% CI, 0.75–1.17) 12 months from index. Significant predictors of adherence and persistence included patient age, total inpatient admissions, number of adverse events, and total hospital visits.ConclusionPatient-specific clinical factors, rather than regimen-specific factors, were the main predictors of oral targeted therapy adherence and persistence. Adherence to oral targeted therapies appears to be similar for patients on QD and BID regimens in the real-world setting.

Linking dose delivery accuracy and planning target margin in radiosurgery based on dose-volume histograms derived from measurement-guided dose reconstruction

In radiosurgery (SRS), the geometric uncertainties of machine-related delivery including image-guidance and hence the planning target volume (PTV) are often evaluated by the end-to-end gamma (γ) comparison that carries no information about the clinical relevance of deviations of individual SRS plans during delivery quality assurance (DQA). A proof-of-concept method was proposed to derive the PTV against both the plan- and the machine-specific delivery errors directly from the clinically relevant dose-volume histograms (DVHs) using measured-guided dose reconstruction (MGDR) during DQA. A liquid-filled detector array and a rotating phantom were used to measure sixteen arc-based radiosurgery treatments with 1 and 2 mm gross tumor volume (GTV)-to-PTV margins, producing MGDR-3D dose distribution on both the phantom and the patient CT for γ index and clinical DVH evaluations, respectively. The PTV was considered optimal when the MGDR showed the desired prescription dose coverage (V pres ) of the GTV (100% in this study). Associations of the binary V pres outcomes (<or =100%) of the GTV with the acceptance level of percent γ pass rate (γPR%) at 90 versus 95% were assessed. Further receiver operator characteristic (ROC) analysis was performed to assess the distance-to-agreement (DTA) and local dose difference (ΔD) criteria that may be suitable for treatment acceptance. From the MGDR, 100% GTV V pres was achieved in 68.8% and 100% of plans with 1 and 2 mm PTV, respectively. V pres outcomes were neither associated with γPR% at 1–2 mm DTA and 1%–3% ΔD nor the acceptance level for MGDR in the patient CT. ROC analysis shows statistically significant AUC values from 0.78–0.84 and 0.79–0.80 for MGDR phantom and patient doses, respectively. DQA by MGDR-DVH objectives offers the unique opportunity of direct assessment of the dose delivery accuracy and hence the optimal PTV without subject to the statistical correlation between γPR% and clinical metrics. Based on multi-criteria DVH objectives, clinical decision can be instantly made to adjust the treatment plan prescription.

Development and piloting of a highly tailored digital intervention to support adherence to antihypertensive medications as an adjunct to primary care consultations

ObjectivesThis paper describes the systematic development and piloting of a highly tailored text and voice message intervention to increase adherence to medication in primary care.MethodsFollowing the Medical Research Council guidance,...

Patient Adherence and Persistence to Oral Targeted Therapies for Hematologic Malignancies: A Retrospective Cohort Study Among Managed Care Enrollees

Existing studies evaluating patient adherence to oral targeted therapies such as tyrosine kinase inhibitors focus on small populations with single malignancies. This study evaluated patterns of use of oral agents in a larger population across multiple hematologic malignancies.Adult patients diagnosed with a hematologic malignancy and prescribed oral targeted therapy between 2011 and 2016 (N = 18,976) were identified from the MarketScan Commercial Claims and Encounters, and Medicare Supplemental databases. Eligible patients were enrolled in monthly prescription plans 6 months before and 12 months after index date (date of first prescription claim) (n = 2,442). Multivariable logistic regressions were used to determine predictors of adherence using the medication possession ratio (MPR), and persistence through prescription refill gaps.The overall median adherence was 0.9 (MPR ≥ 80%) and was comparable between once-daily (QD) and twice-daily (BID) groups (Table). Overall, 59% of patients were persistent at 12 months (Table). Patients on QD and BID products did not have significant differences in adherence (fixed interval MPR, odds ratio, 0.94; 95% CI, 0.75 to 1.18) or persistence (odds ratio, 0.93; 95% CI, 0.75 to 1.17) 12 months from index (Figure). Significant predictors of adherence and persistence included patient age, total inpatient admissions, number of adverse events and total hospital visits (Figure).Patient-specific clinical factors, rather than regimen-specific factors, were the main predictors of oral targeted therapy adherence and persistence. Adherence to oral targeted therapies appears to be similar for patients on QD and BID regimens in the real-world setting. [Display omitted] DisclosuresPatel:Sunesis Pharmaceuticals: Consultancy; Pharmacyclics/Janssen: Speakers Bureau; AstraZeneca: Consultancy, Research Funding, Speakers Bureau; Genentech: Consultancy, Speakers Bureau; Juno Therapeutics: Consultancy; Celgene: Consultancy. Sudhir:ZS Associates: Employment. Kabadi:AstraZeneca: Employment. Huang:ZS Associates: Employment; Novo Nordisk Inc: Equity Ownership; AstraZeneca: Research Funding. Porwal:ZS Associates: Employment. Thakkar:ZS Associates: Employment. Pagel:Gilead: Consultancy; Pharmacyclics, an AbbVie Company: Consultancy.

A systematic review of clinical practice guidelines on the use of low molecular weight heparin and fondaparinux for the treatment and prevention of venous thromboembolism: Implications for research and policy decision-making.

BackgroundVenous thromboembolism (VTE) is a major global cause of morbidity and mortality. Low molecular weight heparin (LMWH) and fondaparinux (FDP) are frequently used to treat and prevent VTE and have a variety of safety and practical advantages over other anticoagulants, including use in outpatient settings. These medications are commonly listed on drug formularies, which act as a gateway for health plan prescription coverage by outlining the circumstances under which patients will be covered for specific drugs and drug products. Because patient access to medications is impacted by the nature of their listing on formularies, they must be rigorously reviewed and modernized as new evidence emerges.MethodsAs part of a broader drug class review team, we completed a systematic review of clinical practice guidelines to determine whether the recommendations they reported aligned with the indications listed for the coverage of LMWH and FDP in an outpatient drug formulary. Guideline quality was assessed using the Appraisal of Guidelines for Research & Evaluation (AGREE) II tool. Recommendation matrices were used to systematically compare, categorize, and summarize included recommendations.ResultsTwenty-seven guidelines were included from which 168 eligible recommendations were identified. Generally, AGREE II domains were adequately addressed; however, domain five (applicability) was poorly addressed. Most recommendations were based on moderate- to low-quality/limited evidence and reported on the use of LMWHs generally; few reported on specific agents.ConclusionsOur findings contributed to the recommendation that the formulary listing for LMWH and FDP be streamlined to include coverage for specific outpatient indications. The paucity of available evidence on the comparative efficacy of specific LMWH agents against each other and FDP limited agent-specific listing recommendations, highlighting the need for high-quality comparative studies on this topic.

Personalizing Prescription of Radiation Therapy Utilizing Genomic Markers of Radiosensitivity

In previous studies, we developed the radio-sensitivity index (RSI) and genomic adjusted radiation dose (GARD) to capture genomic heterogeneity and personalize radiation therapy (RT) prescription. We hypothesize that the current one-size fits-all paradigm to RT prescription is inefficient for individual patients given observed distributions of tumor RSI across large cohorts of patients. We demonstrate a workflow for clinical use of genomic features in RT prescription. We assessed tumor genomics in a cohort of 1229 patients with non-small lung cancer (NSCLC, Cohort 1) using RSI. To model the impact of genomic heterogeneity on RT dose prescription, we utilized a cohort of 60 NSCLC patients treated with surgery and postoperative RT (45 – 70 Gy, median 54 Gy, Cohort 2). For all analyses, expression data (Affymetrix Hu-RSTA-2a520709) were used to calculate RSI. Using RSI, we derive a patient specific alfa to calculate GARD. Previously we demonstrated that lung cancer patients in cohort 2 who achieved a GARD >= 33 had an improved local control (HR=3.4, 1.3, 9.1 p=0.02). We defined the personalized RSI/GARD RT dose prescription (RxRSI) as the physical dose in Gy required to achieve the GARD threshold of 33. We integrated GARD into the planning workflow of a commercial treatment planning system to create personalized genomic radiation treatment plans (pGRT) using standardized plan optimizations for both standard of care (SoC) and RxRSI doses. RxRSI plans were evaluated against standard planning criteria and normal tissue constraints, and compared with SoC prescription plans using biological effective voxel based dose scaling. In cohort 1, RSI demonstrated a bimodal distribution, indicating a uniform treatment dose may be sub-optimal. A similar heterogeneity was observed in cohort 2, (RSI (IQR: 0.25, 0.40), GARD (IQR: 24.7, 38.62)) where we calculated a personalized RxRSI dose for each patient. In 24% of cohort 2, RxRSI dose was lower than the prescribed dose by more than 10%, with median RxRSI at 47Gy. In 60% of the cohort, RxRSI dose was greater than prescribed dose by more than 10%, ranging from 62Gy to 95Gy. pGRT planning achieved both desired target coverage for RxRSI and normal tissue constraints for patients under 74Gy, with esophageal dose falling below clinically acceptable levels for 80% of plans at 88Gy and above. One-size fits-all RT dose prescription may be sub-optimal for some patients given the genomic heterogeneity observed. Using a clinically-validated model (RSI/GARD) we identify that in up to 84% of patients the prescribed dose and personalized RxRSI did not match, suggesting that there is a large opportunity to optimize dose with genomics. A novel pGRT function within a commercial system can effectively optimize plans to present a choice between a personalized RxRSI and SoC treatment plans for consideration. To our knowledge this is the first demonstration of a feasible clinical approach to precision medicine in radiation oncology.

PSMA-Directed Biologically-Guided Radiation Therapy of Castration-Sensitive Oligometastatic Prostate Cancer Patients

Local ablative treatment to oligometastatic (OM) patients can result in long term disease-free survival in cancer patients. The importance of consolidating all tumors in prostate cancer in the modern era is unknown. Stereotactic ablative radiation (SABR) is highly focused, high-dose radiation, but further dose escalation is still limited by target motion, localization uncertainties and difficultly irradiating multiple metastases simultaneously. Biology-guided radiotherapy (BgRT) is currently being developed to utilize PET emission data to guide radiotherapy delivery in real-time and to multiple targets. With this modality, the PET signals act as a biological fiducial that inherently tracks target motion and treatment setup uncertainties. Prostate membrane specific antigen (PSMA) is a cell surface protein that is overexpressed preferentially in prostate cancer and radiolabeled-ligands have been used for unprecedented molecular imaging in prostate cancer. Here we report on a pilot study examining PSMA-directed BgRT using a cohort from our Phase II randomized trial of SABR to men with recurrent low volume (1-3 metastases) metastatic hormone sensitive prostate cancer (HSPC) who have been imaged with PSMA PET-CT. Patients are randomized 2:1 to SABR:observation with minimization to balance assignment by primary intervention, prior hormonal therapy, and PSA doubling time. All men treated with SABR were imaged with PSMA PET-CT at day 1 prior to SABR and day 180 from randomization. Four patients from this trial were used for a proof-of-concept study to compare conventionally planned SABR treatments versus BgRT treatments generated from a prototype treatment planning system (TPS). BgRT treatment plan prescriptions were duplicated from the conventional SABR treatment plans and the dose constraints for organs-at-risk (OARs) followed AAPM TG101 guidelines. No additional dose shaping structures were used for the BgRT plans. All patients had one metastatic site (n= 2 node & n= 2 bone) with an average PTV of 5.1 cc (range = 1.8-9.5 cc). All four BgRT plans met pre-specified planning objectives and were qualitatively acceptable even without the use of optimization structures. The BgRT plans displayed better PTV coverage, V95=96.9±2% versus V95=95.6%±1 for conventional SABR planning, were more heterogeneous [average Dmax of the prescription dose was 149% (range = 137-164%) for BgRT versus 123% (112-131%) for the conventional SABR] and gave more dose on average [Dmean 123% (range = 117-127%) for BgRT versus 112% (range = 109-116%) for conventional SABR] but had similar and in many cases better avoidance of OARs. This is a pilot BgRT planning study from the first randomized Phase II study evaluating the safety and efficacy of SABR in OM HSPC who have been imaged with PSMA PET-CT. Our study suggests comparable treatment plans between conventional and BgRT planned SABR and demonstrates the feasibility of PSMA-directed BgRT-guided SABR for OM HSPC.

Projecting future land use/land cover by integrating drivers and plan prescriptions: the case for watershed applications

Watershed planning is a pivotal exercise for all jurisdictions irrespective of size, landscape complexity, or other nuances. As a result of the intricate relationship between land use/land cover (LULC) and water resources, it becomes prudent to not only develop historical and contemporary LULC data for watershed planning purposes, but more importantly, the production of future LULC datasets has the potential to better inform watershed planners. This study explored an optimal workflow that can be adopted for the production of baseline LULC input images from a moderate spatial resolution sensor such as Landsat, and the identification, translation, and configuration of land change drivers and regional comprehensive plan prescriptions in the creation of future LULC data for a regional watershed. The study conducted in the Lower Chippewa River Watershed, Wisconsin, USA demonstrated that an object-based hybrid classification approach resulted in the generation of improved projected images with a 15% increase in area under the curve (AUC) value compared to a pixel-based hybrid classification method even though both methods displayed comparable overall image classification accuracies (≤ 1.8%). Results further displayed that configuring anthropogenic drivers in a trend format rather than individual year values can result in a more efficient training of a multi-layer perceptron neural network – Markov Chain model. The calibrated and validated model demonstrated that on average, residential, commercial, institutional, green vegetation/shrub, and industrial LULC are expected to grow through 2050, though at a slower rate (12%) compared to contemporary period (39%), while forest and agricultural lands are slated to decline (−2%).

O uso do processo de enfermagem como ferramenta de apoio para o cuidado da criança na atenção domiciliar

Este estudo possui o objetivo de compartilhar a experiência no uso do Processo de Enfermagem como ferramenta de apoio para o cuidado da criança na atenção domiciliar. Trata-se de um estudo descritivo, tendo como participante uma criança e sua família, os quais foram acompanhados em domicílio por uma enfermeira durante alguns meses do ano de 2018, sendo assim, coletados os dados. Os resultados do estudo foram compilados confirme prevê o Processo de Enfermagem, seguindo as etapas de Histórico e Exame Físico, Diagnósticos de Enfermagem, Prescrição ou Plano de Cuidados, Implementação dos Cuidados e Avaliação da Assistência de Enfermagem. Considerou-se que a realização deste processo vislumbrou o levantamento de dados efetivo sobre a família, conduzindo assim, a um plano de cuidados integral e resolutivo em longo prazo. Este estudo possui importância ao demonstrar a utilização eficaz do Processo de Enfermagem em domicilio, conduzindo a uma demanda contemporânea crescente.

Clinical Results of Mean GTV Dose Optimized Robotic-Guided Stereotactic Body Radiation Therapy for Lung Tumors.

We retrospectively evaluated the efficacy and toxicity of gross tumor volume (GTV) mean dose optimized stereotactic body radiation therapy (SBRT) for primary and secondary lung tumors with and without robotic real-time motion compensation. Between 2011 and 2017, 208 patients were treated with SBRT for 111 primary lung tumors and 163 lung metastases with a median GTV of 8.2 cc (0.3-174.0 cc). Monte Carlo dose optimization was performed prioritizing GTV mean dose at the potential cost of planning target volume (PTV) coverage reduction while adhering to safe normal tissue constraints. The median GTV mean biological effective dose (BED)10 was 162.0 Gy10 (34.2-253.6 Gy10) and the prescribed PTV BED10 ranged 23.6-151.2 Gy10 (median, 100.8 Gy10). Motion compensation was realized through direct tracking (44.9%), fiducial tracking (4.4%), and internal target volume (ITV) concepts with small (≤5 mm, 33.2%) or large (>5 mm, 17.5%) motion. The local control (LC), progression-free survival (PFS), overall survival (OS), and toxicity were analyzed. Median follow-up was 14.5 months (1-72 months). The 2-year actuarial LC, PFS, and OS rates were 93.1, 43.2, and 62.4%, and the median PFS and OS were 18.0 and 39.8 months, respectively. In univariate analysis, prior local irradiation (hazard ratio (HR) 0.18, confidence interval (CI) 0.05-0.63, p = 0.01), GTV/PTV (HR 1.01-1.02, CI 1.01-1.04, p < 0.02), and PTV prescription, mean GTV, and maximum plan BED10 (HR 0.97-0.99, CI 0.96-0.99, p < 0.01) were predictive for LC while the tracking method was not (p = 0.97). For PFS and OS, multivariate analysis showed Karnofsky Index (p < 0.01) and tumor stage (p ≤ 0.02) to be significant factors for outcome prediction. Late radiation pneumonitis or chronic rip fractures grade 1-2 were observed in 5.3% of the patients. Grade ≥3 side effects did not occur. Robotic SBRT is a safe and effective treatment for lung tumors. Reducing the PTV prescription and keeping high GTV mean doses allowed the reduction of toxicity while maintaining high local tumor control. The use of real-time motion compensation is strongly advised, however, well-performed ITV motion compensation may be used alternatively when direct tracking is not feasible.

Association between Higher Generic Drug Use and Medicare Part D Star Ratings: An Observational Analysis

BackgroundIncreasing generic drug use, due to potential for cost savings and drug access, is a viable consideration for Medicare prescription drug plans to achieve high star ratings and improve quality of plan offerings for Medicare beneficiaries. ObjectiveTo examine the association between contract-level proportion of generic drugs dispensed (pGDD) and Medicare Part D star ratings. MethodsThis was a retrospective study of linked 2011 Medicare Part D star rating data with contract-level pGDD data. A total of 477 individual Medicare prescription contracts were included, representing 75% of total Prescription Drug Plans and more than 65% of total Medicare Advantage Prescription Drug Plans available by the end of 2010. Primary outcomes were Medicare Part D summary and domain star ratings (1–5 indicating lowest to highest performance), incorporating a range of quality measures for access, cost, beneficiary satisfaction, and health services outcomes and processes. Ordinal logistic regression models were used to examine associations between pGDD and Medicare Part D summary and domain star ratings, controlling for contract type and number of beneficiary enrollment. ResultsHigher pGDD was associated with higher summary star ratings (adjusted odds ratio 1.08 with 95% confidence interval 1.04–1.12) and higher “member experience with drug plan” domain ratings (adjusted odds ratio 1.07 with 95% confidence interval 1.03–1.11). ConclusionsPrescription formulary benefit design targeting increasing generic drug use appears to be associated with improved member experience and higher plan star ratings. Consideration may be given to incorporating pGDD into Medicare Part D star rating measures to improve quality of prescription plans.

The future of tropical forests under the United Nations Sustainable Development Goals

ABSTRACTIn September 2015, member states of the United Nations unanimously adopted the Sustainable Development Goals (SDGs)—a set of 17 ambitions for the post-2015 global development agenda. The goals do not offer a prescriptive plan but establish levers of policy action that seek to improve the three pillars of sustainable development: society, environment, and the economy. To facilitate achieving the SDGs, it will be critical to identify context-specific opportunities and challenges for implementation. Tropical regions of the world currently host not only the highest levels of biodiversity but also some of the highest rates of urbanization and development globally. Moreover, tropical forest deforestation is a globally significant issue; it has adverse impacts on biodiversity, climate systems, and socioeconomic equality. Here, we provide a rapid overview and qualitative assessment of the academic and policy literature on development and tropical forests, using the framework of the SDGs to examine issues broadly relevant to both tropical forests and sustainable development. Our assessment gathers existing knowledge and reveals critical knowledge gaps. In doing so, we identify key synergies between SDGs and tropical forests. We also suggest potential pathways of influence to improve social, environmental, and economic conditions in these rapidly developing regions of the world.

Auto-Contour Guided Prostate Patient Positioning

To use contours automatically generated on the pre-treatment cone-beam CT (CBCT) to improve the registration with the plan CT for prostate image-guided radiation therapy (IGRT). 10 patients, each with 10 to 28 daily kV-CBCTs, had their prostate manually contoured on the plan CT and daily CBCTs. Prostate contours were also automatically generated on the CBCTs. Auto-contours are produced by deformably registering prior CBCTs (atlases) to the current CBCT and deforming the prior contours with the resulting deformation field. This set of deformed prostate contours on the current CBCT is then combined using the STAPLE algorithm. The optimal IGRT shift is determined by comparing the centroid of the manual prostate contour in the CBCT and plan CT. This shift is compared both to the clinical shift that was based on qualitative alignment of the images, and to a centroid shift based on auto-contours. The dosimetric impact of the different shift methods is estimated by overlaying the plan prescription isodose line on the CBCT according to the shifts, and then determining the coverage of the manual prostate and PTV contours. On average there is a 2.3±1.5 mm difference in the superior/inferior (SI) direction between the clinical and centroid shifts. The difference is 0.9±0.7 mm in the left/right (LR) and 1.8±1.5 mm in the anterior/posterior (AP) directions. Using the clinical shifts gave on average 98.7±2.6% coverage of the prostate, and 89.6±3.8% coverage of the PTV by the prescription dose. Centroid based shifts gave significantly better coverage of 99.5±1.1% (P=0.0013) and 92.7±2.4% (P<0.00001) for the prostate and PTV respectively. The reduction in standard deviation also implies more consistent coverage day to day with the centroid shifts. The average dice similarity coefficient of prostate auto-contours to manual contours is 0.91, which equals our intra-observer error. The average time for auto-contouring was 90 seconds on a Tesla K20c GPU. Using auto-contours to determine the centroid produces equivalent shifts to the manual contour centroid shifts, with average differences of 0.8±0.6, 0.4±0.3 and 0.8±0.7 mm in SI, LR and AP directions, respectively. This is to be expected given the consistency of the manual and auto-contours. There are >2 mm differences between our new centroid based shifts and the current clinical, image based shifts, with centroid based shifts providing significantly higher prostate coverage. Auto-contouring provides equivalent shifts to manual centroid based shifts. IGRT can thus be fully automated, resulting in improved prostate coverage.

Deterministic direct aperture optimization using multiphase piecewise constant segmentation.

Direct aperture optimization (DAO) attempts to incorporate machine constraints in the inverse optimization to eliminate the post-processing steps in fluence map optimization (FMO) that degrade plan quality. Current commercial DAO methods utilize a stochastic or greedy approach to search a small aperture solution space. In this study, we propose a novel deterministic direct aperture optimization that integrates the segmentation of fluence map in the optimization problem using the multiphase piecewise constant Mumford-Shah formulation. The Mumford-Shah based direct aperture optimization problem was formulated to include an L2-norm dose fidelity term to penalize differences between the projected dose and the prescribed dose, an anisotropic total variation term to promote piecewise continuity in the fluence maps, and the multiphase piecewise constant Mumford-Shah function to partition the fluence into pairwise discrete segments. A proximal-class, first-order primal-dual solver was implemented to solve the large scale optimization problem, and an alternating module strategy was implemented to update fluence and delivery segments. Three patients of varying complexity-one glioblastoma multiforme (GBM) patient, one lung (LNG) patient, and one bilateral head and neck (H&N) patient with 3 PTVs-were selected to test the new DAO method. For each patient, 20 non-coplanar beams were first selected using column generation, followed by the Mumford-Shah based DAO (DAOMS ). For comparison, a popular and successful approach to DAO known as simulated annealing-a stochastic approach-was replicated. The simulated annealing DAO (DAOSA ) plans were then created using the same beam angles and maximum number of segments per beam. PTV coverage, PTV homogeneity D95D5, and OAR sparing were assessed for each plan. In addition, high dose spillage, defined as the 50% isodose volume divided by the tumor volume, as well as conformity, defined as the van't Riet conformation number, were evaluated. DAOMS achieved essentially the same OAR doses compared with the DAOSA plans for the GBM case. The average difference of OAR Dmax and Dmean between the two plans were within 0.05% of the plan prescription dose. The lung case showed slightly improved critical structure sparing using the DAOMS approach, where the average OAR Dmax and Dmean were reduced by 3.67% and 1.08%, respectively, of the prescription dose. The DAOMS plan substantially improved OAR dose sparing for the H&N patient, where the average OAR Dmax and Dmean were reduced by over 10% of the prescription dose. The DAOMS and DAOSA plans were comparable for the GBM and LNG PTV coverage, while the DAOMS plan substantially improved the H&N PTV coverage, increasing D99 by 6.98% of the prescription dose. For the GBM and LNG patients, the DAOMS and DAOSA plans had comparable high dose spillage but slightly worse conformity with the DAOMS approach. For the H&N plan, DAOMS was considerably superior in high dose spillage and conformity to the DAOSA . The deterministic approach is able to solve the DAO problem substantially faster than the simulated annealing approach, with a 9.5- to 40-fold decrease in total solve time, depending on the patient case. A novel deterministic direct aperture optimization formulation was developed and evaluated. It combines fluence map optimization and the multiphase piecewise constant Mumford-Shah segmentation into a unified framework, and the resulting optimization problem can be solved efficiently. Compared to the widely and commercially used simulated annealing DAO approach, it showed comparable dosimetry behavior for simple plans, and substantially improved OAR sparing, PTV coverage, PTV homogeneity, high dose spillage, and conformity for the more complex head and neck plan.

Modeling evacuation in institutional space: Linking three-dimensional data capture, simulation, analysis, and visualization workflows for risk assessment and communication

This article presents exploratory research to develop new workflows that address the challenges of adequately capturing the geometry and topology of complex institutional spaces, the analysis of prescriptive evacuation plans, and the simulation of human movement and behavior in emergency scenarios. We present a collection of geovisual analytical environments that were developed to permit new ways to view and assess risk, evacuation, and human movement. Part of this research considers how different approaches to the representation of complex institutional space, using three-dimensional capture technologies at multiple resolutions (or derived from conventional formats, such as building plans), have implicit advantages or liabilities in the analysis of risk and human evacuation. We combine three-dimensional data capture methods with geographical information science theory, three-dimensional game engines, three-dimensional evacuation simulations and spatial analyses that address the variability of campus populations, and draw upon three-dimensional modeling and photogrammetry for the assessment of real-world features in digital space. The outcome of this research demonstrates agile workflows that address emergency planning requirements, but could also enable enhanced visual analysis and interactive learning by all campus citizens. Furthermore, this work reveals key considerations and limitations associated with the dynamic nature of evacuation events and the static environments in which they have been simulated.

Impact of an open enrollment service on costs for Medicare Part D beneficiaries

ObjectiveThe primary objective was to determine total estimated cost savings based on a patient’s current medication regimen after comparing available Medicare Part D plans for the upcoming year by using a plan comparison platform. The secondary objective was to determine patient-centered concerns when considering a change in Part D plans. DesignReview of an open enrollment service that included a patient survey and a Part D plan comparison. SettingThis study took place at a single independent community pharmacy in northwest Alabama. ParticipantsFifty-four patients eligible for Medicare Part D were included in this study. Main outcome measuresThe study was a review of an open enrollment service that aids Medicare beneficiaries in selecting a Part D plan that best fits their needs. It included a patient survey and plan comparison using a plan comparison platform, during the 2015 Medicare open enrollment period (October 15 to December 7). The survey assessed patient demographics, pharmacy preferences, and cost concerns. Survey data were used to aid in plan selection and analysis to determine the most common patient-centered concerns when considering a change in plans. ResultsDuring the open enrollment period, 54 patients compared Medicare Part D plans. The majority of participants were female (57%) and ranged in age from 65-69 years (37%) to 70-74 years (25.9%). The majority of patients reported a preference for independent pharmacies (92.6%). Deductible (40.7%) was the biggest concern for patients when comparing the main cost variables for medication insurance. The average total cost difference per patient per year showed that each patient saved an average of $1166.46. ConclusionThe analysis of an independent pharmacy’s open enrollment service determined that a plan comparison platform is a valuable tool in helping patients to compare and select cost-effective Medicare Part D prescription plans and in helping patients save money.

An Evaluation of U.S. National Wildlife Refuge Planning for Off-Road Vehicle Use

AbstractOff-road vehicles (hereafter, ORVs) rank high among public-land management challenges because they are popular, often impair environmental conditions, and may cause conflicts with other recreational users. Unit-level planning for federal lands increasingly translates broad, system-wide objectives, such as maintenance of ecological integrity, into place-based limitations on ORV use to minimize and mitigate adverse impacts on wildlife. We reviewed 176 planning documents covering 313 National Wildlife Refuges (hereafter, Refuges) to understand how planning supports or undermines ORV recreation management. These plans offer an important perspective on ORV management because the Refuges are a large, diverse system of conservation lands where recreation may be permitted only where it is compatible with wildlife protection. Of the plans we evaluated, 24% mentioned ORV use and 12% prescribed some action related to ORVs. The most common prescriptions banned ORV use or limited it to mobility-impaired hunters. Many plans lacked clarity or documentation of analysis in discussing ORV recreation. When analyses grouped ORV use with other activities, such as hunting or other modes of transportation, they often failed to consider the characteristic effects of ORV use. Regardless of how ORV use was categorized, evaluation of its effects seldom considered the full range of environmental impacts documented in the scientific literature. Published research recommends many best practices for managing ORV use and impacts. Though some are habitat specific, five general best-practice categories highlight where planning connects with and diverges from common recommendations. Other land management agencies offer helpful models for implementing these practices in planning. We suggest that public land managers employ tools from each of the five categories: policy formation and public participation, spatial and temporal route planning, permitting, monitoring, and enforcement. The plan prescriptions we examined were strongest in their efforts at route planning. Refuge prescriptions have the most room to improve in detailing how they can work with neighbors and external stakeholders in formulating ORV-use rules.