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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. In this study, we used advanced FSI techniques to investigate the rupture risk of middle cerebral artery bifurcation (MCA) aneurysms, analyzing a cohort of 125 patients treated for a MCA aneurysm at Kepler University Hospital, Linz, Austria. Multivariate analysis identified two significant rupture predictors: High Equivalent Stress Area (HESA; p = 0.049), which quantifies stress distribution relative to the aneurysm surface, and Gaussian curvature (GLN; p = 0.031), which captures geometric complexity. We also introduce the HGD index, a novel composite metric combining HESA, GLN, and Maximum Wall Displacement, designed to enhance predictive accuracy. With a threshold of 0.075, the HGD index exhibited excellent diagnostic performance; in internal validation, 24 of 25 ruptured aneurysms surpassed this threshold, yielding a sensitivity of 0.96. In a 5-fold cross validation the reliability of results was confirmed. Our findings demonstrate that the HGD index provides superior rupture risk stratification compared to conventional single-parameter models, offering a more robust tool for the assessment of complex aneurysmal structures. Further multicenter studies are warranted to refine and validate the HGD index, advancing its potential for clinical application and improving patient outcomes. [ABSTRACT FROM AUTHOR]

Surgical simulators are valuable educational tools for physicians, enhancing their proficiency and improving patient safety. However, they typically still suffer from a lack of realism as they do not emulate dynamic tissue biomechanics haptically and fail to convincingly mimic real‐time physiological reactions. This study presents a dynamic tactile synthetic tissue, integrating both sensory and actuatory capabilities within a fully soft unit, as a core component for soft robotics and future hybrid surgical simulators utilizing dynamic physical phantoms. The adaptive surface of the tissue replica, actuated via hydraulics, is assessed by an embedded carbon black silicone sensor layer using electrical impedance tomography to determine internally or externally induced deformations. The integrated fluid chambers enable pressure and force measurements. The combination of these principles enables real‐time tissue feedback as well as closed loop operation, allowing optimal interaction with the environment. Based on the concepts of soft robotics, such artificial tissues find broad applicability, demonstrated via a soft gripper and surgical simulation applications including a dynamic, artificial brain phantom as well as a synthetic, beating heart. These advancements pave the way toward enhanced realism in surgical simulators including reliable performance evaluation and bear the potential to transform the future of surgical training methodologies. [ABSTRACT FROM AUTHOR]

Background: It has long been known that thyroid disease can lead to changes in energy metabolism, thermoregulation, and anxiety behavior. While these actions have been partially attributed to thyroid hormone (TH) receptor α1 (TRα1) action in the brain, the precise neuroanatomical substrates have remain elusive. Methods: We used PET-CT scans to identify brain regions affected by TH. We then inhibited TRα1 signaling specifically in the most affected region, the zona incerta (ZI), a still mysterious region previously implicated in thermogenesis and anxiety. To this end, we used an adeno-associated virus (AAV) expressing a dominant-negative TRα1R384C in wild-type mice and phenotyped the animals. Finally, we used tyrosine hydroxylase-Cre mice to test specifically the contribution of ZI dopaminergic neurons. Results: Our data showed that AAV-mediated inhibition of TRα1 signaling in the ZI lead to increased energy expenditure at thermoneutrality, while body temperature regulation remained unaffected. Moreover, circulating glucocorticoid levels were increased, and a mild habituation problem was observed in the open field test. No effects were observed when TRα1 signaling was selectively inhibited in dopaminergic neurons. Conclusions: Our findings suggest that altered TH signaling in the ZI is not involved in body temperature regulation but can affect basal metabolism and modulates stress responses. [ABSTRACT FROM AUTHOR]

Background: 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. Method: This method integrates both fluid dynamics and structural mechanics, as well as their mutual interaction, for a comprehensive analysis. Patients with a single unruptured cerebral aneurysm were included. Results: Overall, three scenarios were identified. In scenario A, wall shear stress (WSS) was low, and the oscillatory shear index (OSI) was high in large areas within the region of aneurysm onset (RAO). In scenario B, the quantities indicated a reversed behavior, where WSS was high and OSI was low. In the last scenario C, a behavior in-between was found, with scenarios A and B coexisting simultaneously in the RAO. Structural mechanics demonstrated a similar but independent trend. Further, we analyzed the change in hemodynamics between the onset and a fully developed aneurysm. While scenarios A and C remained unchanged during aneurysm growth, 47% of aneurysms in scenario B changed into scenario A and 20% into scenario C. Conclusions: In conclusion, these findings suggest that WSS and the OSI are reciprocally regulated, and both low and high WSS/OSI conditions can lead to aneurysm onset. [ABSTRACT FROM AUTHOR]

Objective: Although inpatient treatment is highly effective for patients with bulimia nervosa (BN), some patients show a resurgence of symptoms and relapse after discharge. Therefore, the aim of this study is to evaluate the efficacy of a guided smartphone‐based aftercare intervention following inpatient treatment to support recovery. Method: 172 female patients with BN (DSM‐5: 307.51) will be randomized to receive a 16‐week smartphone‐based aftercare intervention (German version of 'Recovery Record') with therapist feedback as an add‐on element to treatment as usual (TAU) or TAU alone. Assessments will take place at baseline (discharge, T0), during the intervention (after 4 weeks, T1), post‐intervention (after 16 weeks, T2) and at 6‐month follow‐up (T3). Primary outcome will be remission at T2. Moderator and mediator analyses will investigate for whom the aftercare intervention suits best and how it works. Conclusions: This is the first randomized controlled trial to examine a guided smartphone‐based aftercare intervention following inpatient treatment of patients with BN. We expect that this innovative aftercare intervention is highly accepted by the patients and that it has the potential to support recovery after inpatient treatment and thereby could contribute to improving aftercare for patients with BN. Highlights: There are several studies reporting relapse rates for patients with bulimia nervosa (BN) after having received remission or abstinence at the end of treatment.This is the first randomized controlled trial (RCT) to investigate the effects of a guided smartphone‐based aftercare following inpatient treatment of patients with BN.If this innovative aftercare intervention is accepted by the patients and supports recovery after inpatient treatment for patients with BN, it could contribute to improving aftercare for patients with BN. [ABSTRACT FROM AUTHOR]