0000000000441134
AUTHOR
Darius Kalasauskas
showing 12 related works from this author
Identification of High-Risk Atypical Meningiomas According to Semantic and Radiomic Features
2020
Up to 60% of atypical meningiomas (World Health Organization (WHO) grade II) reoccur within 5 years after resection. However, no clear radiological criteria exist to identify tumors with higher risk of relapse. In this study, we aimed to assess the association of certain radiomic and semantic features of atypical meningiomas in MRI with tumor recurrence. We identified patients operated on primary atypical meningiomas in our department from 2007 to 2017. An analysis of 13 quantitatively defined radiomic and 11 qualitatively defined semantic criteria was performed based on preoperative MRI scans. Imaging characteristics were assessed along with clinical and survival data. The analysis include…
First multiphoton tomography of brain in man
2016
We report on the first two-photon in vivo brain tissue imaging study in man. High resolution in vivo histology by multiphoton tomography (MPT) including two-photon FLIM was performed in the operation theatre during neurosurgery to evaluate the feasibility to detect label-free tumor borders with subcellular resolution. This feasibility study demonstrates, that MPT has the potential to identify tumor borders on a cellular level in nearly real-time.
Diversity of Clinically Relevant Outcomes Resulting from Hypofractionated Radiation in Human Glioma Stem Cells Mirrors Distinct Patterns of Transcrip…
2020
Hypofractionated radiotherapy is the mainstay of the current treatment for glioblastoma. However, the efficacy of radiotherapy is hindered by the high degree of radioresistance associated with glioma stem cells comprising a heterogeneous compartment of cell lineages differing in their phenotypic characteristics, molecular signatures, and biological responses to external signals. Reconstruction of radiation responses in glioma stem cells is necessary for understanding the biological and molecular determinants of glioblastoma radioresistance. To date, there is a paucity of information on the longitudinal outcomes of hypofractionated radiation in glioma stem cells. This study addresses long-te…
Pharmacological Neuroenhancement, Perceived Stress, and Resilience in Spine Surgeons–A Cross-Sectional Survey
2022
Background Spine surgeons are usually exposed to high workload and demanding work conditions. Although the relationship between pharmacological neuroenhancement (PNE) and resilience (i.e., the ability to recover from stress), as well as perceived stress and resilience-enhancing factors, has been investigated in the general population, less is known about the impact of those factors in spine surgeons. This study aimed to close that gap by investigating the relationship between PNE use and resilience, perceived stress, or resilience-enhancing factors in spine surgeons. Methods We conducted a cross-sectional survey in a sample of 582 spine surgeons in German-speaking countries (Austria, German…
Evaluation of Resection Margin after Image-Guided Dural Tail Resection in Convexity Meningiomas
2021
Infiltration of adjacent dura with meningioma cells is a common phenomenon. Wide resection of the dural tail (DT) to achieve a gross total resection is a general recommendation. We aimed to investigate a tumor cell infiltration of the DT after image-guided resection of convexity meningiomas. The study’s inclusion criteria were the diagnosis of convexity meningioma, planned Simpson I° resection, and an identifiable DT. Intraoperative image-guidance was applied to identify the outer edge of the DT and to guide resection. After resection, en-bloc specimen or four samples of outermost pieces of DT in case of piecemeal resection were sent for histological analysis. In addition to resection margi…
Development and external validation of a clinical prediction model for functional impairment after intracranial tumor surgery
2021
OBJECTIVE Decision-making for intracranial tumor surgery requires balancing the oncological benefit against the risk for resection-related impairment. Risk estimates are commonly based on subjective experience and generalized numbers from the literature, but even experienced surgeons overestimate functional outcome after surgery. Today, there is no reliable and objective way to preoperatively predict an individual patient’s risk of experiencing any functional impairment. METHODS The authors developed a prediction model for functional impairment at 3 to 6 months after microsurgical resection, defined as a decrease in Karnofsky Performance Status of ≥ 10 points. Two prospective registries in…
Amphotericin B Penetrates into the Central Nervous System through Focal Disruption of the Blood-Brain Barrier in Experimental Hematogenous Candida Me…
2019
Hematogenous Candida meningoencephalitis (HCME) is a life-threatening complication of neonates and immunocompromised children. Amphotericin B (AmB) shows poor permeability and low cerebrospinal fluid (CSF) concentrations, but is effective in treatment of HCME. In order to better understand the mechanism of CNS penetration of AmB, we hypothesized that AmB may achieve focally higher concentrations in infected CNS lesions. An in vitro BBB model was serially infected with C. albicans. Liposomal AmB (LAMB) or deoxycholate AmB (DAMB) at 5 μg/ml were then provided, vascular and CNS compartments were sampled 4h later. For in vivo correlation, rabbits with experimental HCME received a single dose of…
The association of patient age with postoperative morbidity and mortality following resection of intracranial tumors
2021
Abstract Introduction The postoperative functional status of patients with intracranial tumors is influenced by patient-specific factors, including age. Research question This study aimed to elucidate the association between age and postoperative morbidity or mortality following the resection of brain tumors. Material and methods A multicenter database was retrospectively reviewed. Functional status was assessed before and 3–6 months after tumor resection by the Karnofsky Performance Scale (KPS). Uni- and multivariable linear regression were used to estimate the association of age with postoperative change in KPS. Logistic regression models for a ≥10-point decline in KPS or mortality were b…
Fungal Infections of the Central Nervous System in Children.
2017
Although uncommon in children, fungal infections of the central nervous system can be devastating and difficult to treat. A better understanding of basic mycologic, immunologic, and pharmacologic processes has led to important advances in the diagnosis and management of these diseases, but their mortality rates remain unacceptably high. In this focused review, we examine the epidemiology and clinical features of the most common fungal pathogens of the central nervous system in children and explore recent advances in diagnosis and antifungal therapy.
RNA-sequencing and bioinformatic analysis to pre-assess sensitivity to targeted therapeutics in recurrent glioblastoma.
2019
e13533 Background: This study developed molecular guided tools for individualized selection of chemotherapeutics for recurrent glioblastoma (rGB). A consortium involving clinical neurooncologists, molecular biologists and bioinformaticians identified gene expression patterns in rGB and quantitatively analyzed pathways involved in response to FDA approved oncodrugs. Methods: From2016 to 2018 biopsies from GB were collected using a multisampling approach. Biopsy material was used to isolate glioma stem-like cells and examined by RNA-sequencing. RNA-seq results were subjected to differential expression (DE) analysis and Oncobox analysis – a bioinformatic tool for quantitative pathway activati…
Psychological Burden in Meningioma Patients under a Wait-and-Watch Strategy and after Complete Resection Is High—Results of a Prospective Single Cent…
2020
The diagnosis of intracranial meningiomas as incidental findings is increasing by growing availability of MRI diagnostics. However, the psychological distress of patients with incidental meningiomas under a wait-and-watch strategy is unknown. Therefore, we aimed to compare the psychosocial situation of meningioma patients under wait-and-watch to patients after complete resection to bridge this gap. The inclusion criteria for the prospective monocenter study were either an incidental meningioma under a wait-and-watch strategy or no neurologic deficits after complete resection. Sociodemographic, clinical, and health-related quality of life and clinical data were assessed. Psychosocial factors…
Intratumoral Heterogeneity and Longitudinal Changes in Gene Expression Predict Differential Drug Sensitivity in Newly Diagnosed and Recurrent Gliobla…
2020
Background: Inevitable recurrence after radiochemotherapy is the major problem in the treatment of glioblastoma, the most prevalent type of adult brain malignancy. Glioblastomas are notorious for a high degree of intratumor heterogeneity manifest through a diversity of cell types and molecular patterns. The current paradigm of understanding glioblastoma recurrence is that cytotoxic therapy fails to target effectively glioma stem cells. Recent advances indicate that therapy-driven molecular evolution is a fundamental trait associated with glioblastoma recurrence. There is a growing body of evidence indicating that intratumor heterogeneity, longitudinal changes in molecular biomarkers and spe…