Micro-Twinning in IN738LC Manufactured with Laser Powder Bed Fusion.

Components manufactured with Metal Laser Powder Bed Fusion (PBF-LB/M) are built in a layerwise fashion. The PBF-LB/M build orientation affects grain morphology and orientation. Depending on the build orientation, microstructures from equiaxed to textured grains can develop.

Robust Determination of Fatigue Crack Propagation Thresholds from Crack Growth Data.

The robust determination of the threshold against fatigue crack propagation ΔKth is of paramount importance in fracture mechanics based fatigue assessment procedures. The standards ASTM E647 and ISO 12108 introduce operational definitions of ΔKth based on the crack propagation rate da/dN and suggest linear fits of logarithmic ΔK- da/dN test data to calculate ΔKth. Since these fits typically suffer from a poor representation of the actual curvature of the crack propagation curve, a method for evaluating ΔKth using a nonlinear function is proposed.

A New Method for the Calculation of Characteristics of Disc Springs with Trapezoidal Cross-Sections and Rounded Edges.

In the European standards specifying disc spring manufacturing, geometry, shape and characteristic, an edge rounding is prescribed. Common methods for the calculation of disc spring characteristics, even in these standards, are based on a rectangular cross-section. This discrepancy can lead to a considerable divergence of the computed characteristic from the characteristic determined by testing.

Comparison of the distribution of lymph node metastases compared to healthy lymph nodes in breast cancer.

Background: Current literature lacks a comparison of lymph node metastases and non-pathological lymph nodes distribution in breast cancer patients. The aim of the current retrospective study was to generate a comprehensive atlas of the lymph node system.

Methods: 143 breast cancer patients underwent F-18-FDG-PET/CT (PET/CT) imaging for staging purposes and were diagnosed with regional lymph node metastases.

Planning Benchmark Study for Stereotactic Body Radiation Therapy of Liver Metastases: Results of the DEGRO/DGMP Working Group on Stereotactic Radiation Therapy and Radiosurgery.

Purpose: Our purpose was to investigate whether liver stereotactic body radiation therapy treatment planning can be harmonized across different treatment planning systems, delivery techniques, and institutions by using a specific prescription method and to minimize the knowledge gap concerning intersystem and interuser differences. We provide best practice guidelines for all used techniques.

Methods And Materials: A multiparametric specification of target dose (gross target volume [GTV], GTV, GTV, planning target volume [PTV]) with a prescription dose of GTV = 3 × 20 Gy and organ-at-risk (OAR) limits were distributed with computed tomography and structure sets from 3 patients with liver metastases.

Impact of CBCT frequency on target coverage and dose to the organs at risk in adjuvant breast cancer radiotherapy.

The current study aims to assess the effect of cone beam computed tomography (CBCT) frequency during adjuvant breast cancer radiotherapy with simultaneous integrated boost (SIB) on target volume coverage and dose to the organs at risk (OAR). 50 breast cancer patients receiving either non-hypofractionated or hypofractionated radiotherapy after lumpectomy including a SIB to the tumor bed were selected for this study. All patients were treated in volumetric modulated arc therapy (VMAT) technique and underwent daily CBCT imaging.

Face Perception and Pareidolia Production in Patients With Parkinson's Disease.

In Parkinson's disease (PD) patients, visual misperceptions are a major problem within the non-motor symptoms. Pareidolia, i.e.

Assessment of the impact of multiple mild-steam decontaminations on the protection performance of disposable KN95 filtering facepiece respirators.

The COVID-19 pandemic caused tremendous supply bottlenecks of single-use filtering facepiece respirators (FFRs) leading to a growing need for a potential reuse. This study assesses the impact of multiple mild-steam decontaminations with 121 °C/2000 mbar/20 min on the protection performance of disposable FFRs. It focuses on FFRs of type KN95 that is recently dominating the markets, but its decontamination is not covered in the literature.

Analysis of using high-precision radiotherapy in the treatment of liver metastases regarding toxicity and survival.

Background: Hepatic metastases occur frequently in the context of many tumor entities. Patients with colorectal carcinoma have already developed liver metastases in 20% at the time of diagnosis, and 25-50% develop metastases in the further course of the disease and therapy. The frequent manifestation and the variable appearance of liver metastases result in an interdisciplinary challenge, regarding treatment management.

Excluding Lung Tissue from the PTV during Internal Mammary Irradiation. A Safe Technique for OAR-Sparing?

The current study aims to determine whether exclusion of lung tissue from planning treatment volume (PTV) is a valid organ at risk (OAR)-sparing technique during internal mammary irradiation (IMNI). Twenty patients with left-sided breast cancer undergoing adjuvant radiotherapy including IMNI after mastectomy or lumpectomy with daily ConeBeam CT (CBCT; median n = 28) were enrolled in the current study. The daily dose distribution of the patients was estimated by recalculating treatment plans on CBCT-scans based on a standard PTV (PTV margin: 5mm-STD) and a modified PTV, which excluded overlapping lung tissue (ExLung).

Patient individual phase gating for stereotactic radiation therapy of early stage non-small cell lung cancer (NSCLC).

Stereotactic body radiotherapy (SBRT) applies high doses and requires advanced techniques to spare surrounding tissue in the presence of organ motion. In this work patient individual phase gating is investigated. We studied peripheral and central primary lung tumors.

Report on planning comparison of VMAT, IMRT and helical tomotherapy for the ESCALOX-trial pre-study.

Background: The ESCALOX trial was designed as a multicenter, randomized prospective dose escalation study for head and neck cancer. Therefore, feasibility of treatment planning via different treatment planning systems (TPS) and radiotherapy (RT) techniques is essential. We hypothesized the comparability of dose distributions for simultaneous integrated boost (SIB) volumes respecting the constraints by different TPS and RT techniques.

The Parkinson disease pain classification system: results from an international mechanism-based classification approach.

Pain is a common nonmotor symptom in patients with Parkinson disease (PD) but the correct diagnosis of the respective cause remains difficult because suitable tools are lacking, so far. We developed a framework to differentiate PD- from non-PD-related pain and classify PD-related pain into 3 groups based on validated mechanistic pain descriptors (nociceptive, neuropathic, or nociplastic), which encompass all the previously described PD pain types. Severity of PD-related pain syndromes was scored by ratings of intensity, frequency, and interference with daily living activities.

An easy way to determine bone mineral density and predict pelvic insufficiency fractures in patients treated with radiotherapy for cervical cancer.

Purpose: The aim of this study was to investigate whether bone mineral density (BMD) as measured in planning computed tomographies (CTs) by a new method is a risk factor for pelvic insufficiency fractures (PIF) after radio(chemo)therapy (R(C)T) for cervical cancer.

Methods: 62 patients with cervical cancer who received definitive or adjuvant radio(chemo)therapy between 2013 and 2017 were reviewed. The PIF were detected on follow-up magntic resonance imaging (MRI).

Correlations of UICC tumor stage and tumor regression on T2-weighted MRI sequences during definitive radiotherapy of cervical cancer.

Background: The purpose of this study is to detect a correlation between the preradiation tumor staging and the relative volumetric regression of the primary tumor through external beam radiation therapy (EBRT).

Methods: Clinical data of 32 patients with a mean age of 60±12 years treated with primary radiation therapy (RT) of cervical carcinoma were analyzed. Union Internationale Contre le Cancer (UICC) stages were T1 = 4 patients, T2 = 15 patients, T3 = 8 patients, T4 = 5 patients; N1 = 26 patients, N0 = 6 patients; and M0 = 25 patients, M1 = 7 patients.

On the Influence of Ultimate Number of Cycles on Lifetime Prediction for Compression Springs Manufactured from VDSiCr Class Spring Wire.

For the generation of fatigue curves by means of fatigue tests, an ultimate number of cycles must be chosen. This ultimate number of cycles also limits the permissible range of the fatigue curve for the design of components. This introduces extremely high costs for testing components that are to be used in the Very High Cycle Fatigue regime.

Toxicity of internal mammary irradiation in breast cancer. Are concerns still justified in times of modern treatment techniques?

Background: The purpose of this study was to estimate the additional risk of side effects attributed to internal mammary node irradiation (IMNI) as part of regional lymph node irradiation (RNI) in breast cancer patients and to compare it with estimated overall survival (OS) benefit from IMNI.

Material And Methods: Treatment plans ( = 80) with volumetric modulated arc therapy (VMAT) were calculated for 20 patients (4 plans per patient) with left-sided breast cancer from the prospective GATTUM trial in free breathing (FB) and in deep inspiration breath hold (DIBH). We assessed doses to organs at risk ((OARs) lung, contralateral breast and heart) during RNI with and without additional IMNI.

Single-institutional outcome-analysis of low-dose stereotactic body radiation therapy (SBRT) of adrenal gland metastases.

Background: Adrenal gland metastases are a common diagnostic finding in various tumor diseases. Due to the increased use of imaging methods, they are diagnosed more frequently, especially in asymptomatic patients. SBRT has emerged as a new, alternative treatment option in the field of radiation oncology.

Effect of hypofractionation on the incidental axilla dose during tangential field radiotherapy in breast cancer.

Objective: Tangential field irradiation in breast cancer potentially treats residual tumor cells in the axilla after sentinel lymph node biopsy (SLNB). In recent years, hypofractionated radiotherapy has gained importance and currently represents the recommended standard in adjuvant breast cancer treatment for many patients. So far, the impact of hypofractionation on the effect of incidental lymph node irradiation has not be addressed.

The dosimetric impact of stabilizing spinal implants in radiotherapy treatment planning with protons and photons: standard titanium alloy vs. radiolucent carbon-fiber-reinforced PEEK systems.

Background: Throughout the last years, carbon-fibre-reinforced PEEK (CFP) pedicle screw systems were introduced to replace standard titanium alloy (Ti) implants for spinal instrumentation, promising improved radiotherapy (RT) treatment planning accuracy. We compared the dosimetric impact of both implants for intensity modulated proton (IMPT) and volumetric arc photon therapy (VMAT), with the focus on uncertainties in Hounsfield unit assignment of titanium alloy.

Methods: Retrospective planning was performed on CT data of five patients with Ti and five with CFP implants.

Stereotactic body radiotherapy (SBRT) in patients with lung metastases - prognostic factors and long-term survival using patient self-reported outcome (PRO).

Objectives: The present study aims to evaluate long-term side-effects and outcomes and confirm prognostic factors after stereotactic body radiotherapy (SBRT) of pulmonary lesions. This is the first work that combines the investigated data from patient charts and patient-reported outcome (PRO) up to 14 years after therapy.

Materials And Methods: We analyzed 219 patients and 316 lung metastases treated between 2004 and 2019.

A Novel Algorithm for the Determination of Walker Damage in Loaded Disc Springs.

In this paper, a novel algorithm for the determination of Walker damage in loaded disc springs is presented. The algorithm takes a 3D-scan of a disc spring, measured residual stresses, material parameters, and spring loads as inputs. It outputs a distribution of Walker damage over the surface area of the input disc spring.

Dosimetric comparison of organs at risk using different contouring guidelines for definition of the clinical target volume in anal cancer.

Background: There are different contouring guidelines for definition of the clinical target volume (CTV) for intensity-modulated radiation therapy (IMRT) of anal cancer (AC). We conducted a planning comparison study to evaluate and compare the dose to relevant organs at risk (OARs) while using different CTV definitions.

Methods: Twelve patients with a primary diagnosis of anal cancer, who were treated with primary chemoradiation (CRT), were selected.

Patient-Reported Outcome (PRO) as an Addition to Long-Term Results after High-Precision Stereotactic Radiotherapy in Patients with Secreting and Non-Secreting Pituitary Adenomas: A Retrospective Cohort Study up to 17-Years Follow-Up.

High-precision radiotherapy has been established as a valid and effective treatment option in patients with pituitary adenomas. We report on outcome after fractionated stereotactic radiotherapy (FSRT) in correlation with patient-reported outcomes (PROs). We analyzed 69 patients treated between 2000 and 2019.