Hemodynamic Study of a Patient-Specific Intracranial Aneurysm: Comparative Assessment of Tomographic PIV, Stereoscopic PIV, In Vivo MRI and Computational Fluid Dynamics.

Introduction: Wall shear stress (WSS) is associated with the growth and rupture of an intracranial aneurysm. To reveal their underlying connections, many image-based computational fluid dynamics (CFD) studies have been conducted. However, the methodological validations using both in vivo medical imaging and in vitro optical flow measurements were rarely accompanied in such studies.

Patient-Reported Outcomes-Guided Adaptive Radiation Therapy for Head and Neck Cancer.

Purpose: To identify which patient-reported outcomes (PROs) may be most improved through adaptive radiation therapy (ART) with the goal of reducing toxicity incidence among head and neck cancer patients.

Methods: One hundred fifty-five head and neck cancer patients receiving radical VMAT (chemo)radiotherapy (66-70 Gy in 30-35 fractions) completed the MD Anderson Symptom Inventory, MD Anderson Dysphagia Inventory (MDADI), and Xerostomia Questionnaire while attending routine follow-up clinics between June-October 2019. Hierarchical clustering characterized symptom endorsement.

Determining Clinical Patient Selection Guidelines for Head and Neck Adaptive Radiation Therapy Using Random Forest Modelling and a Novel Simplification Heuristic.

Purpose: To determine which head and neck adaptive radiotherapy (ART) correction objectives are feasible and to derive efficient ART patient selection guidelines.

Methods: We considered various head and neck ART objectives including independent consideration of dose-sparing of the brainstem/spinal cord, parotid glands, and pharyngeal constrictor, as well as prediction of patient weight loss. Two-hundred head and neck cancer patients were used for model development and an additional 50 for model validation.

Multicenter evaluation of therapeutic strategies of inpatients with osteoporotic vertebral fractures in Germany.

Purpose: The aim of this study was to assess therapeutic strategies of inpatients with osteoporotic thoracolumbar fractures (OTF) in Germany.

Methods: Prospective multi-center study including 16 German-speaking trauma centers over a period of 7 months. All inpatients with OTF were included.

Lasso logistic regression to derive workflow-specific algorithm performance requirements as demonstrated for head and neck cancer deformable image registration in adaptive radiation therapy.

As automation in radiation oncology becomes more common, it is important to determine which algorithms are equivalent for a given workflow. Often, algorithm comparisons are performed in isolation; however, clinical context can provide valuable insight into the importance of algorithm features and error magnification in subsequent workflow steps. We propose a strategy for deriving workflow-specific algorithm performance requirements.

Epigenetic Patterns and Geographical Parthenogenesis in the Alpine Plant Species (Ranunculaceae).

Polyploidization and the shift to apomictic reproduction are connected to changes in DNA cytosine-methylation. Cytosine-methylation is further sensitive to environmental conditions. We, therefore, hypothesize that DNA methylation patterns would differentiate within species with geographical parthenogenesis, i.

Effects of Temperature Treatments on Cytosine-Methylation Profiles of Diploid and Autotetraploid Plants of the Alpine Species (Ranunculaceae).

The exposure to environmental stress can trigger epigenetic variation, which may have several evolutionary consequences. Polyploidy seems to affect the DNA methylation profiles. Nevertheless, it abides unclear whether temperature stress can induce methylations changes in different cytotypes and to what extent a treatment shift is translated to an epigenetic response.

Data clustering to select clinically-relevant test cases for algorithm benchmarking and characterization.

Algorithm benchmarking and characterization are an important part of algorithm development and validation prior to clinical implementation. However, benchmarking may be limited to a small collection of test cases due to the resource-intensive nature of establishing 'ground-truth' references. This study proposes a framework for selecting test cases to assess algorithm and workflow equivalence.

4-D Echo-Particle Image Velocimetry in a Left Ventricular Phantom.

Left ventricular (LV) blood flow is an inherently complex time-varying 3-D phenomenon, where 2-D quantification often ignores the effect of out-of-plane motion. In this study, we describe high frame rate 4-D echocardiographic particle image velocimetry (echo-PIV) using a prototype matrix transesophageal transducer and a dynamic LV phantom for testing the accuracy of echo-PIV in the presence of complex flow patterns. Optical time-resolved tomographic PIV (tomo-PIV) was used as a reference standard for comparison.

Radiation Oncology Device Approval in the United States and Canada.

Background Medical devices are a crucial component in the field of radiation oncology. The review and licensing of radiation oncology devices (RODs) is managed on a national basis in Canada by Health Canada and in the United States by the Food and Drug Administration (FDA). The purpose of this study was to examine differences in ROD licensing timelines between Health Canada and the FDA that may impact the ability of Canadians to access the most up-to-date radiation oncology care.

Tomographic PIV in a model of the left ventricle: 3D flow past biological and mechanical heart valves.

Left ventricular flow is intrinsically complex, three-dimensional and unsteady. Its features are susceptible to cardiovascular pathology and treatment, in particular to surgical interventions involving the valves (mitral valve replacement). To improve our understanding of intraventricular fluid mechanics and the impact of various types of prosthetic valves thereon, we have developed a custom-designed versatile left ventricular phantom with anatomically realistic moving left ventricular membrane.

Blood cytokine pattern and clinical outcome in knee arthroplasty patients: comparative analysis 5 years after standard versus "hypoallergenic" surface coated prosthesis implantation.

Background and purpose - Metal sensitivity might provoke complications after arthroplasty. Correspondingly, coated "hypoallergenic" implants are of interest but long-term follow-up data are missing. Thus, we assessed immunological and clinical parameters in such patients.

Classification of Osteoporotic Thoracolumbar Spine Fractures: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

Study Design: Expert opinion.

Objectives: Osteoporotic vertebral fractures are of increasing medical importance. For an adequate treatment strategy, an easy and reliable classification is needed.

Treatment of Fractures of the Thoracolumbar Spine: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

Study Design: consensus paper with systematic literature review.

Objective: The aim of this study was to establish recommendations for treatment of thoracolumbar spine fractures based on systematic review of current literature and consensus of several spine surgery experts.

Methods: The project was initiated in September 2008 and published in Germany in 2011.

Framework for the quantitative assessment of adaptive radiation therapy protocols.

Background: Adaptive radiation therapy (ART) "flags," such as change in external body contour or relative weight loss, are widely used to identify which head and neck cancer (HNC) patients may benefit from replanned treatment. Despite the popularity of ART, few published quantitative approaches verify the accuracy of replan candidate identification, especially with regards to the simple flagging approaches that are considered current standard of practice. We propose a quantitative evaluation framework, demonstrated through the assessment of a single institution's clinical ART flag: change in body contour exceeding 1.

Effects of cold treatments on fitness and mode of reproduction in the diploid and polyploid alpine plant Ranunculus kuepferi (Ranunculaceae).

Background And Aims: Alpine plants grow in harsh environments and are thought to face occasional frost during the sensitive reproductive phase. Apomixis (asexual reproduction via seed) can be advantageous when sexual reproduction is disturbed by cold stress. Apomictic polyploids tend to grow in colder climates than their sexual diploid relatives.

Reconstructing geographical parthenogenesis: effects of niche differentiation and reproductive mode on Holocene range expansion of an alpine plant.

Asexual taxa often have larger ranges than their sexual progenitors, particularly in areas affected by Pleistocene glaciations. The reasons given for this 'geographical parthenogenesis' are contentious, with expansion of the ecological niche or colonisation advantages of uniparental reproduction assumed most important in case of plants. Here, we parameterized a spread model for the alpine buttercup Ranunculus kuepferi and reconstructed the joint Holocene range expansion of its sexual and apomictic cytotype across the European Alps under different simulation settings.

Pathways to polyploidy: indications of a female triploid bridge in the alpine species (Ranunculaceae).

Polyploidy is one of the most important evolutionary processes in plants. In natural populations, polyploids usually emerge from unreduced gametes which either fuse with reduced ones, resulting in triploid offspring (triploid bridge), or with other unreduced gametes, resulting in tetraploid embryos. The frequencies of these two pathways, and male versus female gamete contributions, however, are largely unexplored.

Patient With Scald Burn of the Esophagus.

Burns of the esophagus are usually caused by chemical substances. In our report, we present a case of burn injury burn caused by swallowing boiling water under the influence of controlled substances. During the initial diagnostic procedures, a CT scan was performed.

Clinical implementation of an electron monitor unit dosimetry system based on task group 71 report and a commercial calculation program.

Many clinics still use monitor unit (MU) calculations for electron treatment planning and/or quality assurance (QA). This work (1) investigates the clinical implementation of a dosimetry system including a modified American Association of Physicists in Medicine-task group-71 (TG-71)-based electron MU calculation protocol (modified TG-71 electron [mTG-71E] and an independent commercial calculation program and (2) provides the practice recommendations for clinical usage. Following the recently published TG-71 guidance, an organized mTG-71E databook was developed to facilitate data access and subsequent MU computation according to our clinical need.

Correlations of polyploidy and apomixis with elevation and associated environmental gradients in an alpine plant.

Apomictic plants expand their geographical distributions more to higher elevations compared to their sexual progenitors. It was so far unclear whether this tendency is related to mode of reproduction itself or represents a side effect of polyploidy. Apomixis is advantageous for range expansions as no mating partners and pollinators are needed (Baker's rule).

A matter of scale: apparent niche differentiation of diploid and tetraploid plants may depend on extent and grain of analysis.

Aim: Emerging polyploids may depend on environmental niche shifts for successful establishment. Using the alpine plant as a model system, we explore the niche shift hypothesis at different spatial resolutions and in contrasting parts of the species range.

Location: European Alps.

Sofosbuvir plus simeprevir for the treatment of HCV genotype 4 patients with advanced fibrosis or compensated cirrhosis is highly efficacious in real life.

Chronic hepatitis C virus (HCV) infection is a major cause of chronic liver disease and liver-related death. Recently, multiple regimens of different direct-acting antiviral agents (DAAs) have been registered. Although treatment with sofosbuvir (SOF) and simeprevir (SMV) is registered for the treatment of genotype 4 patients in some countries, data on efficacy of this combination are lacking.

Early versus late surgery of thoracic spine fractures in multiple injured patients: is early stabilization always recommendable?

Background Context: Many institutions' retrospective studies investigated the effect of the timing of surgery on outcomes of polytraumatized patients with severe lesions of the thoracic spine and mainly found a better outcome for patients who were operated on less than 72 hours posttrauma.

Purpose: We conducted a prospective study in a Level I trauma center to validate the retrospective data and to investigate other variables, in addition to the timing of surgery that may influence patient outcomes.

Study Design: Prospective observational clinical study.