Repetitive Early Ga-FAPI PET Acquisition Comparing Ga-FAPI-02, Ga-FAPI-46, and Ga-FAPI-74: Methodologic and Diagnostic Implications for Malignant, Inflammatory/Reactive, and Degenerative Lesions.

Ga-labeled fibroblast activation protein (FAP) inhibitor (Ga-FAPI) PET targets Ga-FAPI-positive activated fibroblasts and is a promising imaging technique for various types of cancer and nonmalignant pathologies. However, discrimination between malignant and nonmalignant Ga-FAPI-positive lesions based on static PET with a single acquisition time point can be challenging. Additionally, the optimal imaging time point for Ga-FAPI PET has not been identified yet, and different Ga-FAPI tracer variants are currently used.

Neuroradiological emergency consultations during the first year of the COVID-19 pandemic.

Background: Measures taking aim at minimizing the risk of coronavirus transmission and fear of infection may affect decisions to seek care for other medical emergency conditions. The purpose of this analysis was to analyze intermediate-term effects of the COVID-19 pandemic on neuroradiological emergency consultations (NECs).

Methods: We conducted an ambispective study on NEC requests to a university hospital from a teleradiological network covering 13 hospitals in Germany.

Variability of acquisition phase of computed tomography angiography in acute ischemic stroke in a real-world scenario.

Objectives: The informative value of computed tomography angiography (CTA) depends on the contrast phase in the vessels which may differ depending on the level of local expertise.

Methods: We retrospectively measured vessel contrast density from CTA scans in patients presenting with acute ischemic stroke to a comprehensive stroke center (CSC) or to one of eight primary stroke centers (PSC). CTAs were classified into arterial or venous phases as well as into 1 of 5 phases (early arterial, peak arterial, equilibrium, peak venous, and late venous).

Variability of computed tomography angiography coverage of lung parenchyma in acute stroke.

Background: Computed tomography angiography (CTA) of the head and neck during acute ischemic stroke (AIS) usually includes visualization of lung apices. The possibility to evaluate for pulmonary changes, e.g.

Analysis of a Surgical Series of 21 Cerebral Radiation Necroses.

Background: There is no standard approach to differentiate cerebral radiation necrosis from tumor recurrence and no standard treatment pathway for symptomatic lesions. In addition, reports on histology-proven radiation necrosis and the underlying pathophysiology are scarce and highly relevant.

Methods: Our monocentric, retrospective analysis included 21 histology-proven cerebral radiation necroses.

Evaluation of three automatic brain vessel segmentation methods for stereotactical trajectory planning.

Background And Objective: Stereotactical procedures require exact trajectory planning to avoid blood vessels in the trajectory path. Innovation in imaging and image recognition techniques have facilitated the automatic detection of blood vessels during the planning process and may improve patient safety in the future. To assess the feasibility of a vessel detection and warning system using currently available imaging and vessel segmentation techniques.

Deep MRI brain extraction: A 3D convolutional neural network for skull stripping.

Brain extraction from magnetic resonance imaging (MRI) is crucial for many neuroimaging workflows. Current methods demonstrate good results on non-enhanced T1-weighted images, but struggle when confronted with other modalities and pathologically altered tissue. In this paper we present a 3D convolutional deep learning architecture to address these shortcomings.

Imaging cell size and permeability in biological tissue using the diffusion-time dependence of the apparent diffusion coefficient.

The purpose of this study was to analyze and evaluate a model of restricted water diffusion between equidistant permeable membranes for cell-size and permeability measurements in biological tissue. Based on the known probability distribution of diffusion distances after the diffusion time τ in a system of permeable membranes characterized by three parameters (membrane permeability P, membrane distance L, and free diffusivity D0), an equivalent dimensionless model was derived with a probability distribution characterized by only a single (dimensionless) tissue parameter [Formula: see text]. Evaluating this proposed model function, the dimensionless diffusion coefficient [Formula: see text] was numerically calculated for 60 values of the dimensionless diffusion time [Formula: see text] and 35 values of [Formula: see text].