Clinical Neuroradiology最新文献

Objectives: To conduct a comprehensive comparative assessment of clinical performance between the novel TaminoVIA stent and the LVIS stent for endovascular treatment of unruptured intracranial aneurysms (UIAs).

Methods: This prospective, multi-center, randomized, open-label, parallel positive-controlled, non-inferiority trial was conducted by 13 centers in China. Patients with UIAs were randomized in a 1:1 ratio to receive endovascular treatment (EVT) with the TaminoVIA stent or the LVIS stent. The primary outcome was successful occlusion at 6‑month follow-up, assessed by a blinded core laboratory. The non-inferiority boundary was set at 12%. Secondary outcomes included immediate procedural success, recanalization rates, and safety endpoints.

Results: Between March 2022 and April 2024, 203 patients were enrolled and randomized. Full Analysis Set (FAS) analysis showed a 6-month successful occlusion rate of 89.90% (89/99) in the TaminoVIA stent group, compared to 87.00% (87/100) in the LVIS stent group, with a difference of +2.90% (95% CI, -5.97% to 11.77%; P < 0.01). Immediate occlusion rates were comparable (68.89% vs. 61.54%; P = 0.35), and recanalization rates at 6 months were identical (1.11% vs. 1.10%; P > 0.99). The incidence of severe adverse events (SAEs, 13.13% vs. 15.00%, P = 0.84), device-related complications (2.02% vs. 0%, P = 0.25) and procedure-related SAEs (2.02% vs. 2.00%, P > 0.99) were comparable between the two groups. Both PPS and FAS analyses exceeded the non-inferiority boundary.

Conclusions: The TaminoVIA stent demonstrated non-inferiority to LVIS in both efficacy and safety for IA embolization. These findings support its clinical adoption, though long-term durability requires further validation.

Clinical trial registration number: ChiCTR2400092436.

Background: Magnetic resonance imaging (MRI) is a crucial tool for visualizing orbital structures and detecting eye pathologies. However, manual segmentation of orbital anatomy is challenging due to the complexity and variability of the structures. Recent advancements in deep learning (DL), particularly convolutional neural networks (CNNs), offer promising solutions for automated segmentation in medical imaging. This study aimed to train and evaluate a U-Net-based model for the automated segmentation of key orbital structures.

Methods: This retrospective study included 117 patients with various orbital pathologies who underwent orbital MRI. Manual segmentation was performed on four anatomical structures: the ocular bulb, ocular tumors, retinal detachment, and the optic nerve. Following the UNet autoconfiguration by nnUNet, we conducted a five-fold cross-validation and evaluated the model's performances using Dice Similarity Coefficient (DSC) and Relative Absolute Volume Difference (RAVD) as metrics.

Results: nnU-Net achieved high segmentation performance for the ocular bulb (mean DSC: 0.931) and the optic nerve (mean DSC: 0.820). Segmentation of ocular tumors (mean DSC: 0.788) and retinal detachment (mean DSC: 0.550) showed greater variability, with performance declining in more challenging cases. Despite these challenges, the model achieved high detection rates, with ROC AUCs of 0.90 for ocular tumors and 0.78 for retinal detachment.

Conclusions: This study demonstrates nnU-Net's capability for accurate segmentation of orbital structures, particularly the ocular bulb and optic nerve. However, challenges remain in the segmentation of tumors and retinal detachment due to variability and artifacts. Future improvements in deep learning models and broader, more diverse datasets may enhance segmentation performance, ultimately aiding in the diagnosis and treatment of orbital pathologies.

Purpose: Bacterial contamination has been reported to occur during angiographies, although data on its frequency and relevance are limited. The purpose of our study was to determine whether angiographic materials such as catheters and guide wires remain sterile during angiographies. We sought to differentiate between different materials, and to detect the frequency, the extent and the spectrum of bacterial contamination.

Methods: We prospectively collected 698 fluid or material samples from 100 neuroangiographies. Per angiography we analyzed proximal ends and distal tips of catheters and guide wires, and fluid samples from the water container (working bowl) in which materials were stored during the angiography. We analyzed the frequency and extent of contamination and determined the bacterial spectrum.

Results: The majority of samples (51.4%) were contaminated. There was no angiography that showed no contamination (0%). The highest proportion of contaminated samples was found in the fluid from the working bowl after completion of the examination (92.9%). Catheters and wires were contaminated in 34.1-49.2% of samples. Contamination of the samples increased with longer duration of the angiographic procedures. Most of the bacterial species were environmental or skin contaminants (86.2%).

Conclusion: Bacterial contamination during diagnostic neuroangiographies or interventions is a frequent finding although its clinical significance is believed to be small. Bacterial contamination increases with longer duration of angiographic procedures.

Purpose: Modern endovascular techniques enable the treatment of various neurovascular diseases. Given the complexity of these interventions, a certification system was introduced to ensure standardized care at specialized treatment centers. We used a driving-time-based isochrone approach to identify care gaps in different German Society of Interventional Radiology (DeGIR) certified neurovascular treatment centers.

Methods: DeGIR-certified neurovascular centers for minimally invasive stroke care (module E), neurovascular vessel anomalies (module F), and neurovascular therapy (module EF) were geocoded and driving-time-based isochrones were calculated for 30, 60, 90, and 120 min. The resulting contours were aggregated and combined with the 2025 population estimates from the Global Human Settlement Layer to estimate residents' access.

Results: The analysis identified gaps in under-60-minute reachability, notably in northeastern Germany and parts of Rhineland-Palatinate, Saarland, and the southwest, with modules EF and F most affected, while module E fared better. Within 120 min, coverage was nearly complete across all modules. On a population level, 59.4% of residents lived within 30 min, 92.81% within 60 min, and 99.98% within 120 min of a module E center. Module F reached 45.8%, 84.26%, and 99.73%, respectively, with module EF showing intermediate accessibility.

Discussion: The driving-time-based isochrone approach identifies regions where access to specialized neurovascular care is limited-a critical issue in emergencies like stroke or aneurysm hemorrhage. Although immediate stroke care is generally more accessible than care for neurovascular anomalies, thrombectomy within an acceptable timeframe is not available to the entire population. These findings can guide strategies to enhance neurovascular care across Germany.

Introduction: Acute ischemic stroke (AIS) is the most common neurological complication of infective endocarditis (IE), occurring in 20-40% of patients. In this context, while mechanical thrombectomy (MT) is the standard treatment for patients with AIS due to large-vessel occlusion (LVO), its efficacy and safety in patients with stroke secondary to IE remain unclear.

Objective: Therefore, a more robust analysis of the efficacy and safety of MT in patients with AIS due to IE was conducted to address the gaps identified in previous studies.

Methods: An extensive search of PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases was conducted from inception to December 2024. The endpoints of interest were: (1) favorable functional outcomes at 90 days, (2) successful recanalization, (3) symptomatic intracranial hemorrhage (sICH), (4) any intracranial hemorrhage (aICH), and (5) overall mortality. The pooled proportion rates were employed with a random effects model with 95% Confidence Intervals (CI) and risk ratios (RR) for binary outcomes with 95% CI. I² statistics and Cochran Q test were performed to verify the heterogeneity.

Results: Eight studies published between 2017 and 2024 enrolled 2037 patients (mean age 57.9 years, 62.3% women), of whom 1401 (69%) received mechanical or endovascular thrombectomy for Infective Endocarditis-Related Large Vessel Occlusion (IE-LVO) stroke. A pooled proportion of 29.0% for favorable functional outcomes (mRS 0-2) was reported (95% CI 14.0-43.0%; I² = 65.7%). Successful recanalization (mTICI 2b-3) was observed in 76.0% of patients (95% CI 68.0-84.0%; I² = 23.6%). sICH was reported in 19.0% (95% CI 0.0-38.0%; I² = 49.2%) and aICH in 30.0% of the patients (95% CI 23.0-38.0%; I² = 78.3%). A pooled proportion of 33.0% for all-cause mortality was evidenced (95% CI 21.0-45.0%; I² = 90.4%). A significantly lower incidence of favorable functional outcomes (mRS 0-2) was observed in patients with IE-LVO who underwent MT compared to non-IE-LVO patients (RR 0.48; 95% CI 0.31-0.75; I² = 0.0%), and no significant difference in the incidence of aICH was found between patients with IE-LVO and those with non-IE-LVO who underwent MT (RR 1.38; 95% CI 0.96-1.98; I² = 62.4%).

Conclusion: High successful recanalization rates were achieved in this population through MT, demonstrating its potential as an effective treatment for IE-LVO. However, the clinical outcomes of patients with IE-LVO were significantly unfavorable compared with those of patients without IE-LVO.

Purpose: There is no dedicated stent for isolated venous pulsatile tinnitus (IVPT). This retrospective study aimed to evaluate the the clinical outcomes and associated factors of Precise stent (Cordis) implantation in the management of IVPT.

Methods: We analyzed data from IVPT patients treated at our center between December 2009 and August 2024. Baseline characteristics, venous sinus morphology, endovascular techniques, clinical outcomes, and follow-up data were reviewed.

Results: Among 111 IVPT patients, 64 (57.7%) underwent cranial venous sinus stenting (CVSS) using the Precise stent, with 59 (92.2%) being women. IVPT resolved immediately after CVSS in all cases. Over a mean follow-up of 90.9 ± 42.7 months, 18 patients (28.1%) experienced postoperative headaches, all female, with 61.1% reporting symptoms within the first week. Headaches had a mean duration of 44.9 ± 70.5 days and an average visual analog scale score of 3.4 ± 1.5, with 94.5% described as pressure-like. Younger age was significantly associated with headache occurrence (P < 0.05), while other factors, including stent size and operation time, showed no correlation.

Conclusion: Precise stent implantation in venous sinus is highly effective for treating IVPT, but postoperative headaches, particularly in younger women, are a common complication. Further research is needed to mitigate these side effects and enhance long-term patient outcomes.

Purpose: In outpatient settings, extensive patient records must frequently be reviewed under time constraints, making efficient extraction and summarization of key clinical information essential. Large language models (LLMs) are potentially useful for this task but require validation for clinical reliability. This study assesses OpenAI's GPT-4o for generating structured summaries to assist in neurovascular consultation preparation, aiming to increase efficiency by automating critical data extraction.

Methods: A prospective study was conducted from May to August 2024 at a tertiary care hospital, involving a total of 70 patients. Structured summaries were generated by GPT-4o using a predefined template. Extracted data were categorized into aneurysm-specific details, imaging summaries, and patient-specific clinical factors. Accuracy and completeness were assessed by clinicians, with performance measured using precision, recall, specificity, and accuracy.

Results: High accuracy (≥ 0.96) was measured across most categories. In aneurysm-and patient-specific data, extraction performance varied based on stability over time. Aneurysm location and other stable details were extracted consistently, while changes in aneurysm size and medication lists showed variations. In rare cases, aneurysm details were misattributed to a different aneurysm within the same patient. Imaging summaries were generally concise and clinically useful, though their effectiveness declined when summarizing multiple prior studies.

Conclusion: Neurovascular patient data was effectively structured by GPT-4o, demonstrating high accuracy with minimal errors. While occasional misattributions like outdated information were observed, reliable citation of sources facilitated easy verification. These findings support integrating LLM-generated summaries into neurovascular consultations, with further optimization needed for temporal data tracking and on-premise implementation to address privacy concerns.

Introduction: Emergent carotid artery stenting (eCAS) is frequently performed in acute ischemic stroke to restore cerebral perfusion in patients with high-grade carotid stenosis or dissection. In the absence of prior dual antiplatelet therapy (DAPT), these procedures carry a heightened risk of acute in-stent thrombosis. Tirofiban, an intravenous glycoprotein IIb/IIIa inhibitor with rapid onset of action, has been proposed as a bridging antiplatelet strategy, although its efficacy and safety in the neurovascular setting remain uncertain.

Objective: analysis to evaluate the efficacy and safety of prophylactic tirofiban administration in patients undergoing eCAS without prior DAPT.

Methods: A systematic review and meta-analysis were conducted according to PRISMA guidelines. Studies comparing intravenous tirofiban to control (no tirofiban or alternative agents) in patients undergoing eCAS were included. Risk ratios (RR) were calculated using a random-effects model.

Results: Four studies comprising 649 patients were included. Tirofiban use was associated with a lower incidence of acute in-stent thrombosis (RR 0.21; 95% CI 0.09-0.49; I² = 0%). No significant differences were found between tirofiban and control groups regarding sICH (RR 0.45; 95% CI 0.13-1.52; I² = 41.4%), aICH (RR 1.28; 95% CI 0.64-2.59; I² = 13.4%), or all-cause mortality (RR 0.72; 95% CI 0.41-1.26; I² = 34.7%).

Conclusion: Tirofiban appears to reduce the risk of acute in-stent thrombosis after eCAS without increasing the incidence of hemorrhagic complications or mortality. Further randomized trials are needed to validate these findings and define optimal periprocedural antiplatelet strategies.

Purpose: Functional MRI can be used to identify individual language-sensitive brain regions in the setting of presurgical diagnostics to improve functional postoperative outcome. In this study, a proven language task was adapted into German and tested with regard to its effectiveness, robustness and reliability in a time frame appropriate for the clinical setting. In addition, two different analysis approaches were compared to address the problem of arbitrary statistical thresholds commonly used in the clinical routine to derive contrast maps.

Methods: On two different days, 24 healthy volunteers were examined in a 3T MRI, whereby the task was run twice in each session. The fMRI included two conditions in a block design, reading of sentences and reading of pronounceable nonword lists. We quantified brain activity by using subject-specific, functionally defined ROIs on the one hand and standardized, anatomically defined ROIs on the other. We then tested, whether the two different analyses indicated robust activation of language-sensitive brain regions, and whether effect sizes were reliable across sessions.

Results: Subject-specific functional ROIs as well as anatomical ROIs led to significant positive effect sizes in the major language sensitive regions of the left hemisphere. However, subject-specific functional ROIs resulted in significantly larger effect sizes and a higher reliability in comparison to anatomical ROIs.

Conclusion: The choice of analysis method has a significant impact on the result. For paradigms with short measurement times and little signal change as common in clinical routine, it is highly recommended to use the subject-specific functional ROIs approach.