Fluid structure Interaction analysis for rupture risk assessment in patients with middle cerebral artery aneurysms.

Accurate rupture risk assessment is essential for optimizing treatment decisions in patients with cerebral aneurysms. While computational fluid dynamics (CFD) has provided critical insights into aneurysmal hemodynamics, most analyses focus on blood flow patterns, neglecting the biomechanical properties of the aneurysm wall. To address this limitation, we applied Fluid-Structure Interaction (FSI) analysis, an integrative approach that simulates the dynamic interplay between hemodynamics and wall mechanics, offering a more comprehensive risk assessment.

Fluid-Structure Interaction Simulations of the Initiation Process of Cerebral Aneurysms.

Hemodynamics during the growth process of cerebral aneurysms are incompletely understood. We developed a novel fluid-structure interaction analysis method for the identification of relevant scenarios of aneurysm onset. This method integrates both fluid dynamics and structural mechanics, as well as their mutual interaction, for a comprehensive analysis.

Machine Learning-Based Prediction of Chronic Shunt-Dependent Hydrocephalus After Spontaneous Subarachnoid Hemorrhage.

Background: Chronic posthemorrhagic hydrocephalus often arises following spontaneous subarachnoid hemorrhage (SAH). Timely identification of patients predisposed to develop chronic shunt-dependent hydrocephalus may significantly enhance clinical outcomes.

Methods: We performed an analysis of 510 SAH patients treated at our institution between 2013 and 2018.

Open Microsurgical Cerebral Aneurysm Treatment After Failed Endovascular Therapy: An Evaluation of Aneurysm Treatment Frequencies in All Neurovascular Centers Across Austria and the Czech Republic Over 20 Years.

Background And Objectives: Endovascular treatment of cerebral aneurysms has tremendously advanced over the past decades. Nevertheless, aneurysm residual and recurrence remain challenges after embolization. The objective of this study was to elucidate the portion of embolized aneurysms requiring open surgery and evaluate whether newer endovascular treatments have changed the need for open surgery after failed embolization.

Turning the operating room into a mixed-reality environment: a prospective clinical investigation for cerebral aneurysm clipping.

Objective: The overall aim of this study was to demonstrate the potential benefit of a novel mixed-reality-head-mounted display (MR-HMD) on the spatial orientation of surgeons.

Methods: In a prospective clinical investigation, the authors applied for the first time a new multicamera navigation technology in an operating room setting that allowed them to directly compare MR-HMD navigation to standard monitor navigation. In the study, which included 14 patients with nonruptured middle cerebral artery aneurysms, the authors investigated how intuitively and effectively surgical instruments could be guided in 5 different visual navigation conditions.

Feasibility, Clinical Potential, and Limitations of Trans-Burr Hole Ultrasound for Postoperative Evaluation of Chronic Subdural Hematoma: A Prospective Pilot Study.

Background And Objectives: Chronic subdural hematoma (CSDH) is commonly managed through burr hole surgery. Routine follow-up using computed tomography (CT) imaging is frequently used at many institutions, contributing to significant radiation exposure. This study evaluates the feasibility, safety, and reliability of trans-burr hole sonography as an alternative postoperative imaging modality, aiming to reduce radiation exposure by decreasing the frequency of CT scans.

From molecular signatures to radiomics: tailoring neurooncological strategies through forecasting of glioma growth.

Objective: Contemporary oncological paradigms for adjuvant treatment of low- and intermediate-grade gliomas are often guided by a limited array of parameters, overlooking the dynamic nature of the disease. The authors' aim was to develop a comprehensive multivariate glioma growth model based on multicentric data, to facilitate more individualized therapeutic strategies.

Methods: Random slope models with subject-specific random intercepts were fitted to a retrospective cohort of grade II and III gliomas from the database at Kepler University Hospital (n = 191) to predict future mean tumor diameters.

Microsurgical Clipping of Unruptured Anterior Circulation Aneurysms-A Global Multicenter Investigation of Perioperative Outcomes.

Background And Objectives: Microsurgical aneurysm repair by clipping continues to be highly important despite increasing endovascular treatment options, especially because of inferior occlusion rates. This study aimed to present current global microsurgical treatment practices and to identify risk factors for complications and neurological deterioration after clipping of unruptured anterior circulation aneurysms.

Methods: Fifteen centers from 4 continents participated in this retrospective cohort study.

Machine learning based outcome prediction of microsurgically treated unruptured intracranial aneurysms.

Machine learning (ML) has revolutionized data processing in recent years. This study presents the results of the first prediction models based on a long-term monocentric data registry of patients with microsurgically treated unruptured intracranial aneurysms (UIAs) using a temporal train-test split. Temporal train-test splits allow to simulate prospective validation, and therefore provide more accurate estimations of a model's predictive quality when applied to future patients.

Discovery and systematic assessment of early biomarkers that predict progression to severe COVID-19 disease.

Background: The clinical course of COVID-19 patients ranges from asymptomatic infection, via mild and moderate illness, to severe disease and even fatal outcome. Biomarkers which enable an early prediction of the severity of COVID-19 progression, would be enormously beneficial to guide patient care and early intervention prior to hospitalization.

Methods: Here we describe the identification of plasma protein biomarkers using an antibody microarray-based approach in order to predict a severe cause of a COVID-19 disease already in an early phase of SARS-CoV-2 infection.

Reduction of spondylolisthesis and restoration of lumbar lordosis after anterior lumbar interbody fusion (ALIF).

Background: Anterior lumbar interbody fusion (ALIF) is a well-established surgical treatment option for various diseases of the lumbar spine, including spondylolisthesis. This study aimed to evaluate the postoperative correction of spondylolisthesis and restoration of lumbar and segmental lordosis after ALIF.

Methods: Patients with spondylolisthesis who underwent ALIF between 2013 and 2019 were retrospectively assessed.

Frequency and characteristics of bacterial and viral low-grade infections of the intervertebral discs: a prospective, observational study.

Study Design: Monocentric, prospective, observational study.

Objective: The clinical relevance of bacterial colonization of intervertebral discs is controversial. This study aimed to determine a possible relationship between bacterial and viral colonization and low-grade infection of the discs.

Accidental Dural Tears in Minimally Invasive Spinal Surgery for Degenerative Lumbar Spine Disease.

One of the most frequent complications of spinal surgery is accidental dural tears (ADTs). Minimal access surgical techniques (MAST) have been described as a promising approach to minimizing such complications. ADTs have been studied extensively in connection with open spinal surgery, but there is less literature on minimally invasive spinal surgery (MISS).

The physical sacrifice of thinking: Investigating the relationship between thinking and physical activity in everyday life.

Physical activity level is an important contributor to overall human health and obesity. Research has shown that humans possess a number of traits that influence their physical activity level including social cognition. We examined whether the trait of "need for cognition" was associated with daily physical activity levels.

An investigation of measurement validity for a hemispheric activation scale.

In this paper we report the outcomes of two attempts to correlate the Zenhausern Preference Questionnaire (PT) with the Polarity Questionnaire (PQ). Across two laboratories we consistently found no correlation between these two scales. Our findings are consistent with a previous attempt to validate the PQ (Genovese, 2005).

Making estimates and sensitivity to anchors: exploring the role of hemispheric processing.

In this paper we set out to explore how the processing differences associated with the respective hemispheres would influence susceptibility to anchoring effects. To do so we provided participants with both a positive and negatively valenced anchoring task. Based on prior research, we predicted stronger anchoring effects under conditions of right hemisphere activation and relatively attenuated anchoring effects under left hemisphere activation.

Effects of turbidity and prey density on the foraging success of age 0 year yellow perch Perca flavescens.

Laboratory experiments were conducted to determine how larval and juvenile yellow perch Perca flavescens respond to changes in prey density when exposed to different levels and types of turbidity (phytoplanktonic or sedimentary). Across prey densities, consumption by P. flavescens tended to be less in phytoplanktonic turbidity compared with sedimentary turbidity.

Inhomogeneities in wall stress measured by microergometry in the heart muscle in situ.

Microergometry is a method which we have developed as a tool to measure local mesh-tension within the myocardial weave at any measuring site of both ventricles and the septum on the beating heart in situ. In a mapping procedure on pig and dog hearts, both in control conditions and in the hypertrophied state after aortic banding, local mesh-tension was measured in several areas and in up to eight depths proceeding from the epicardium to the endocardium: Probe-to-fibre coupling is definitely more stable in the canine myocardium than in the porcine heart muscle, probably due to a more effective connective tissue fettering of the canine myocardial weave. The observed longitudinal gradient, with the highest tension in the base, of control dog hearts was levelled out in the hypertrophied hearts.

The assessment of intramural stress alignment on the beating heart in situ using micro-ergometry: functional implications.

The main local stress transmission pathways in the left ventricular base, midportion and apex in up to seven layers have been assessed in normal dog and porcine hearts, in hypertrophied dog hearts, and in three pig hearts having undergone a temporary left ventricular outflow stricture. The rotational sensitivity of needle force probes was used to determine the focal surface-parallel direction of the myocardial tension vector. In all places investigated the orientation of the force transmission pathways differs slightly from the morphologically determined fibre alignment.

High-frequency oscillation in an adult porcine model.

Objective: Controversy exists as to whether high-frequency oscillatory ventilation can be used on babies and small laboratory animals only, or whether high-frequency oscillatory ventilation can also be efficient in the adult patient and large (> 65 kg body weight) laboratory animals. Moreover, controversy exists as to whether limitations in high-frequency oscillation efficiency are caused by the size and shape of the bronchial system, by the lack of low impedant intersegmental gas flow in lung parenchyma, or by inappropriate high-frequency ventilators and ancillary hardware. Therefore, our objective in this study using the adult pig as a model of the adult patient was to test whether the adult airway system is suited to the use of high-frequency oscillatory ventilation or whether there are geometrical, structural, or functional limitations to efficient ventilation by high-frequency oscillation.

[High-frequency artificial respiration. II. Intratracheal high-frequency pressure changes with a rotation-valve catheter].

From the history of ventilatory support, the early studies of Auer und Meltzer only now seem to find a functional explanation. A rotating valve mounted on the tip of an endotracheal tube delivers a widespread gas bolus. The turbulent flow acts as a stirring device on the intrapulmonary gas volume.