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Background: The most frequent therapy of hydrocephalus is the implantation of ventriculoperitoneal shunts for diverting cerebrospinal fluid from the ventricles into the peritoneum. We compared two adjustable valves, the proGAV and proGAV 2.0, for complications which resulted in revision operations.
Methods: Four hundred patients who underwent primary shunt implantation between 2014 and 2020 were analyzed for overall revision rate, one-year revision rate, revision free survival and overall survival observing patient age group, gender, etiology of hydrocephalus, implantation site, prior diversion of cerebrospinal fluid and cause of revision.
Results: All data were available of all 400 patients (female/male 208/192). Overall, 99 patients underwent revision surgery after primary implantation. ProGAV valve was implanted in 283 patients, proGAV 2.0 in 117 patients. There was no significant difference between the two shunt valves concerning revision rate (p=0.8069), one-year revision rate (p=0.9077), revision free survival (p=0.6921) and overall survival (p=0.3232). Furthermore, regarding one-year revision rate, we observed no significant difference between the two shunt valves in pediatric patients (40.7% vs 27.6%; p=0.2247). Revision operation had to be performed more frequently in pediatric patients (46.6% vs 24.8%; p=0.0093) with a significant higher number of total revisions with proGAV than proGAV 2.0 (55.9% vs. 27.6%; p=0.0110) most likely due to longer follow up in the proGAV -group.
Conclusion: According to the target variables we analyzed, aside from lifetime revision rate in pediatric patients there is no significant difference between the two shunt valves. From our subjective point of view, implantation of the newer proGAV 2.0 valve is preferable due to higher adjustment comfort for both patients and physicians.
Background: The development of robotic systems has provided an alternative to frame-based stereotactic procedures. The aim of this experimental phantom study was to compare the mechanical accuracy of the Robotic Surgery Assistant (ROSA) and the Leksell stereotactic frame by reducing clinical and procedural factors to a minimum.
Methods: To precisely compare mechanical accuracy, a stereotactic system was chosen as reference for both methods. A thin layer CT scan with an acrylic phantom fixed to the frame and a localizer enabling the software to recognize the coordinate system was performed. For each of the five phantom targets, two different trajectories were planned, resulting in 10 trajectories. A series of five repetitions was performed, each time based on a new CT scan. Hence, 50 trajectories were analyzed for each method. X-rays of the final cannula position were fused with the planning data. The coordinates of the target point and the endpoint of the robot- or frame-guided probe were visually determined using the robotic software. The target point error (TPE) was calculated applying the Euclidian distance. The depth deviation along the trajectory and the lateral deviation were separately calculated.
Results: Robotics was significantly more accurate, with an arithmetic TPE mean of 0.53 mm (95% CI 0.41–0.55 mm) compared to 0.72 mm (95% CI 0.63–0.8 mm) in stereotaxy (p < 0.05). In robotics, the mean depth deviation along the trajectory was −0.22 mm (95% CI −0.25 to −0.14 mm). The mean lateral deviation was 0.43 mm (95% CI 0.32–0.49 mm). In frame-based stereotaxy, the mean depth deviation amounted to −0.20 mm (95% CI −0.26 to −0.14 mm), the mean lateral deviation to 0.65 mm (95% CI 0.55–0.74 mm).
Conclusion: Both the robotic and frame-based approach proved accurate. The robotic procedure showed significantly higher accuracy. For both methods, procedural factors occurring during surgery might have a more relevant impact on overall accuracy.
Vascular guidance is critical in developmental vasculogenesis and pathological angiogenesis. Brain tumors are strongly vascularized, and antiangiogenic therapy was anticipated to exhibit a strong anti-tumor effect in this tumor type. However, vascular endothelial growth factor A (VEGFA) specific inhibition had no significant impact in clinical practice of gliomas. More research is needed to understand the failure of this therapeutic approach. EphrinB2 has been found to directly interact with vascular endothelial growth factor receptor 2 (VEGFR2) and regulate its activity. Here we analyzed the expression of ephrinB2 and EphB4 in human glioma, we observed vascular localization of ephrinB2 in physiology and pathology and found a significant survival reduction in patients with elevated ephrinB2 tumor expression. Induced endothelial specific depletion of ephrinB2 in the adult mouse (efnb2i∆EC) had no effect on the quiescent vascular system of the brain. However, we found glioma growth and perfusion altered in efnb2i∆EC animals similar to the effects observed with antiangiogenic therapy. No additional anti-tumor effect was observed in efnb2i∆EC animals treated with antiangiogenic therapy. Our data indicate that ephrinB2 and VEGFR2 converge on the same pathway and intervention with either molecule results in a reduction in angiogenesis.
Anti-inflammatory response of Vitamin D on extracranial vessels after subarachnoid hemorrhage
(2023)
Oral e-Poster Presentations - Booth 1: Vascular A (Aneurysms), September 25, 2023, 1:00 PM - 2:30 PM
Background: Vitamin D has been promoted to vascular regeneration in non-cerebral arteries because of its anti-inflammatory properties. Systematic inflammatory reaction as a multifactorial complication after subarachnoid hemorrhage (SAH), correlated with higher mortality and poor outcome, is the result of a multifactorial mechanism with vasoactive inflammation on extracranial vessels. We therefore hypothesized that vitamin D attenuates the systemic vascular inflammatory reaction.
Methods: We investigated the effect of vitamin D pretreatment (100 ng/kg/d; 5 days) in a blood injection SAH model in adult male C57BL6 mice. Vasomotor function (via wire myograph) of carotid and femoral artery and neurological deficits were measured. Different inflammatory factors such as tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), vascular cell adhesion molecule (VCAM) and intercellular adhesion molecule (ICAM), were also tested.
Results: A significantly enhanced vasorelaxation was identified in Vitamin D pretreated mice (SAH-VitD versus SAH-control: p<0,001; n=10). Missing a relevant difference in vasocontraction of carotid and femoral artery comparing SAH mice with and without vitamin D treatment, there was a significantly higher endothelial related vasorelaxing effect in treated SAH mice (p<0,01, n=5). Neurological deficits in vitamin D pre-treated SAH mice were significantly decreased (p<0,05; n=10). All tested inflammatory factors were down-regulated in vitamin D pre-treated mice (SAH-VitD versus SAH-control: p<0,0001; n=10).
Conclusions: Extracranial vascular Inflammation after SAH, as one of the influencing components in the follow-up after SAH onset, was significantly attenuated by Vitamin D pretreatment. Furthermore, anti-inflammatory effect of vitamin D resulted in a decrease of extracranial vasoconstriction and neurological deficits. Further research should be focused on vitamin D to optimize therapeutic strategies for SAH patients in critical care units.
Background: Glioblastoma (GBM) patients are at particularly high risk for thrombotic complications. In the event of a postoperative pulmonary embolism, therapeutic anticoagulation (tAC) is indispensable. The impact of therapeutic anticoagulation on recurrence pattern in GBM is currently unknown. Methods: We conducted a matched-pair cohort analysis of 57 GBM patients with or without tAC that were matched for age, sex, gross total resection and MGMT methylation status in a ratio of 1:2. Patients’ characteristics and clinical course were evaluated using medical charts. MRI characteristics were evaluated by two independent authors blinded to the AC status. Results: The morphologic MRI appearance in first GBM recurrence showed a significantly higher presence of multifocal, midline crossing and sharp demarcated GBM recurrence patterns in patients with therapeutic tAC compared to the matched control group. Although statistically non-significant, the therapeutic tAC cohort showed increased survival. Conclusion: Therapeutic anticoagulation induced significant morphologic changes in GBM recurrences. The underlying pathophysiology is discussed in this article but remains to be further elucidated.
Despite intensive research, glioblastoma remains almost invariably fatal. Various promising drugs targeting specific aspects of glioma biology, in addition to or as an alternative to antiproliferative chemotherapy, were not successful in larger clinical trials. Further insights into the biology of glioma and the mechanisms behind the evasive-adaptive response to targeted therapies is needed to help identify new therapeutic targets, prognostics, or predictive biomarkers. As a modulator of the canonically oncogenic Rho-GTPase pathway, Lipid phosphate phosphatase-related protein type 5 (LPPR5) is pivotal in influencing growth, angiogenesis, and therapeutic resistance. We used a GL261 murine orthotopic allograft glioma model to quantify the tumor growth and to obtain tissue for histological and molecular analysis. Epicortical intravital epi-illumination fluorescence video microscopy of the tumor cell spheroids was used to characterize the neovascular architecture and hemodynamics. GL261-glioma growth was delayed and decelerated after LPPR5 overexpression (LPPR5OE). We observed increased tumor cell apoptosis and decreased expression and secretion of vascular endothelial growth factor A in LPPR5OE glioma. Hence, an altered micro-angioarchitecture consisting of dysfunctional small blood vessels was discovered in the LPPR5OE tumors. Sunitinib therapy eliminated these vessels but had no effect on tumor growth or apoptosis. In general, LPPR5 overexpression generated a more benign, proapoptotic glioma phenotype with delayed growth and a dysfunctional vascular architecture.
EphrinB2–EphB4 signaling is critical during embryogenesis for cardiovascular formation and neuronal guidance. Intriguingly, critical expression patterns have been discovered in cancer pathologies over the last two decades. Multiple connections to tumor migration, growth, angiogenesis, apoptosis, and metastasis have been identified in vitro and in vivo. However, the molecular signaling pathways are manifold and signaling of the EphB4 receptor or the ephrinB2 ligand is cancer type specific. Here we explore the impact of these signaling pathways in neurooncological disease, including glioma, brain metastasis, and spinal bone metastasis. We identify potential downstream pathways that mediate cancer suppression or progression and seek to understand it´s role in antiangiogenic therapy resistance in glioma. Despite the Janus-faced functions of ephrinB2–EphB4 signaling in cancer Eph signaling remains a promising clinical target.