Clinical Neuroradiology最新文献

Selection of appropriate imaging sequences protocols for cranial magnetic resonance imaging (MRI) is crucial to address the medical question and adequately support patient care. Inappropriate protocol selection can compromise diagnostic accuracy, extend scan duration, and increase the risk of misdiagnosis. Typically, radiologists determine scanning protocols based on their expertise, a process that can be time-consuming and subject to variability. Language models offer the potential to streamline this process. This study investigates the capability of bidirectional encoder representations from transformers (BERT)-based models to suggest appropriate MRI protocols based on referral information.A total of 410 anonymized electronic referrals for cranial MRI from a local order-entry system were categorized into nine protocol classes by an experienced neuroradiologist. A locally hosted instance of four different, pre-trained BERT-based classifiers (BERT, ModernBERT, GottBERT, and medBERT.de) were trained to classify protocols based on referral entries, including preliminary diagnoses, prior treatment history, and clinical questions. Each model was additionally fine-tuned for local language on a large dataset of electronic referrals.The model based on medBERT.de with local language fine-tuning was the best-performing model and correctly predicted 81% of all protocols, achieving a macro-F1 score of 0.71, macro-precision and macro-recall values of 0.73 and 0.71, respectively. Moreover, we were able to show that local language fine-tuning led to performance improvements across all models.These results demonstrate the potential of language models to predict MRI protocols, even with limited training data. This approach could accelerate and standardize radiological protocol selection, offering significant benefits for clinical workflows.

Background: Embolization of the middle meningeal artery (EMMA) is a promising novel technique for the treatment of patients with chronic subdural hematomas (cSDH).

Methods: After a nationwide query in Germany, patients with cSDH, treated with EMMA were retrospectively analyzed. Patient and cSDH characteristics, procedural parameters, complications, and rates of treatment failure (TF; residual cSDH > 10 mm, cSDH progression or requirement of rescue surgery) were investigated. TF rates were compared between first-time treatments and treatments of recurrent cSDH, patients receiving embolization and surgery and those being embolized only, different types of embolic agents (particles vs. liquid agents) and between patients with and without antithrombotic medication.

Results: 718 EMMAs (420 unilateral, 149 bilateral) were performed in 569 patients in 30 German neurovascular centers. 57.1% were first-time treatments and 42.9% were treatments of recurrent cSDHs. The most frequently used embolic agents were particles (56.2%), followed by copolymer-based liquid embolic agents (19.6%). The rate of symptomatic procedure-related complications was 2.5%. After a mean follow-up of 6.5 months, TF was observed in 16.2% across all treatments and was more frequent after the treatment of recurrent cSDHs (19.8% vs. 13.5%, p = 0.045) and in patients taking antithrombotic drugs (17.7% vs. 11.5%; p = 0.044). TF was not significantly different regarding the type of embolic agent or additional surgery.

Conclusions: In this nationwide multi-center study, EMMA was associated with favorable clinical outcomes and a low complication rate, supporting the results of recently published randomized controlled trials. TF was more frequent in recurrent cSDH treatments and in patients taking antithrombotic drugs.

Purpose: This study aimed to characterize spinal cord microstructure in healthy subjects using high angular resolution diffusion imaging (HARDI) and tractography.

Methods: Forty-nine healthy subjects (18-50 years, divided into 2 age groups) were included in a prospective study. HARDI of the cervical spinal cord were acquired using a 3T MRI scanner with: 64 directions, b‑value: 1000s/mm², reduced field-of-view (zonally magnified oblique multi-slice), and opposed phase-encoding directions. Distortions were corrected using the FSL software package. Fiber tracking was performed using a deterministic approach with DSI-Studio software. Tensor metrics-fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD)-and tractography statistics were then extracted, at each spine level, and after grey-white matter segmentation.

Results: The microstructural organization of the spinal cord differed between upper and lower cervical spine levels: FA, and AD significantly decreased (p < 0.001); and RD significantly increased (p < 0.05) in lower levels, demonstrating changes in axonal density and myelinated fibers according to a cranio-caudal axis. FA, MD, AD, and RD values were significantly higher in spinal cord white matter (p < 0.0001), compared to grey matter. Age was not associated with a significant change in FA, while there is for MD, AD and RD (p < 0.05). Spinal cord tractography may provide information on the architectural organization of fibers and spinal tracts.

Conclusion: This study proposes a database in cervical spinal cord HARDI, allowing to study the microstructural organization of the spinal cord in healthy subjects, and providing a foundation for comparison with patients presenting spinal cord pathologies.

Purpose: The aim of our study was to assess the mid-term efficacy and safety of the FRED X flow diverting stent (FDS) in the treatment of intracranial aneurysms. The FRED X FDS is relatively new with limited data on its longer-term effectiveness and safety profile.

Methods: Patients with intracranial aneurysms treated with the FRED X FDS at two UK centres, between March 2021 and July 2022 with at least 18 months follow-up, were retrospectively reviewed. Clinical, procedural and imaging data was analyzed.

Results: Twenty-two patients with 24 aneurysms treated with the FRED X device, and had completed at least 18 months of follow-up, were included in this study. The rate of complete aneurysm occlusion (Raymond-Roy Class I) was 83.3% at a mean follow-up duration of 21.5 months. One case of major adverse event (4.3%) related to a post-procedural stroke which is also the only case of permanent neurological deficit (4.3%) in our cohort. Three cases of minor adverse events (13.0%) and 2 cases of asymptomatic adverse events (8.7%) were also recorded.

Conclusion: Use of the FRED X FDS to treat intracranial aneurysms has acceptable safety profile and efficacy in the mid-term.

Background: The Hyperdense Middle Cerebral Artery Sign (HMCAS) is an early marker of acute MCA occlusion on non-contrast CT (NCCT), which has been linked with stroke type and thrombus composition.

Aims: To assess the prognostic value of HMCAS in M1 occlusion patients treated with endovascular thrombectomy and explore its predictive value across different patients.

Methods: Patients with M1 occlusion were selected from the ANGEL-ACT registry, which comprised 1793 individuals. Cohorts were divided based on the presence of HMCAS. The primary outcome was functional independence (mRS 0-2) at 90 days. Secondary outcomes included excellent outcome (mRS 0-1), good functional outcome (mRS 0-3), modified first pass effect (mFPE), successful recanalization, intracranial hemorrhage, and 90-day mortality. Propensity score matching (PSM) was employed to adjust for confounders, with 96 patients in each matched group. Subgroup analysis was performed to determine whether the effect of HMCAS on clinical outcomes differed between groups.

Results: Among 714 acute M1 occlusion patients, 96 (13.4%) had HMCAS. PSM analysis showed that HMCAS was independently associated with mFPE (OR: 1.97, 95% CI: 1.04-3.75, p = 0.038) but had no significant effects on other clinical outcomes. There was a significant association between HMCAS and functional independence for patients who underwent direct thrombectomy but not for patients who underwent bridging therapy (P for interaction = 0.033).

Conclusion: This study indicates that in patients with acute M1 occlusion undergoing EVT, HMCAS on pretreatment NCCT is not significantly associated with functional independence but is linked to a higher first-pass recanalization rate. Its clinical impact on outcomes depends on whether intravenous thrombolysis is administered before thrombectomy.

Purpose: This study aimed to investigate the factors influencing favourable clinical outcomes in idiopathic intracranial hypertension (IIH) patients with venous sinus stenosis (VSS) who received stenting treatment.

Methods: In this prospective cohort study, we analyzed a total of 172 IIH patients with VSS treated with venous sinus stenting. Clinical outcomes were categorized as either "complete resolved" or "improved". We employed multivariable logistic regression modeling to identify independent factors associated with the clinical outcomes. The predictive accuracy of the model was assessed using receiver operating characteristic (ROC) analysis.

Results: Out of the total cohort, 126 patients exhibited asymptomatic clinical outcomes, while 46 patients showed improved clinical outcomes. Patients with asymptomatic clinical outcomes demonstrated notably lower preoperative BMI (26.8 kg/m² versus 28.7 kg/m², P = 0.013). In multivariate analysis, preoperative BMI (odds ratio [OR] = 1.108, 95% confidence interval [CI] = 1.009-1.216) was an independent factor of complete resolution of the symptoms. In the receiver operating characteristic (ROC) analysis, the identified cut-off BMI for the highest sensitivity (0.5) and specificity (0.754) was determined to be 29.3 kg/m².

Conclusion: Lower BMI may be associated with the complete resolution of symptoms in IIH patients with VSS who received venous sinus stenting treatment.

Introduction: Although stentrievers (SRs) are widely used for mechanical thrombectomy (MT), the impact of device dimensions on optimizing reperfusion outcomes in high clot burden cases is unclear. Our study aimed to investigate the effect of SR size on angiographic and clinical outcomes in patients with acute terminal internal cerebral artery (TICA) occlusion.

Methods: We analyzed ROSSETTI registry data to compare technical and clinical outcomes of TICA occlusion patients treated with MT without rescue therapy, according to SR diameter and length: 6 × 41-50 mm, 6 × 20-40 mm, and <6 × 20-50 mm. The first-pass effect (FPE) was defined as achieving a TICI2c‑3 after a single pass.

Results: We included 491 patients, 240 (41.5%) in 6 × 41-50 group, 117 (20.2%) in 6 × 20-40 group, and 134 (23.2%) in < 6 × 20-50 group. The MT procedure time for the 6 × 41-50 group was shorter, but the FPE rate was similar across all groups. The highest final mTICI 2c‑3 rate was in 6 × 41-50 group (81.2%), compared to 6 × 20-40 group (68.4%) and 4-6 × 20-50 group (72.4%) (p = 0.016). Distal catheter use was associated with final mTICI 0-2b (62% of patients). Clinical outcomes were similar between the groups. Larger diameter and longer length of the SR, as well as not using an intermediate catheter, were independent predictors of final mTICI 2c‑3. The use of 6 × 41-50 SRs (OR 1.64, 95% CI 1.06-2.52; p = 0.024) and distal catheter use (OR 0.62, 95%CI 0.40-0.96; p = 0.034) were independent predictors of final mTICI 2c‑3.

Conclusions: Use of longer and larger SRs in acute intracranial TICA occlusion improves final reperfusion rate.

Background & purpose: Non-stenotic (< 50%) carotid plaques are increasingly recognized as a potential mechanism for ischemic stroke. We assessed the prevalence of such plaques in patients with low-risk neurologic events and evidence of DWI (Diffusion Weighted Imaging)-positive ischemia.

Methods: This is a post-hoc exploratory analysis from the DOUBT study, a prospective, observational, multicenter study of patients with low-risk transient or persistent minor focal neurological symptoms. Patients who had baseline CT angiography (CTA) and an MRI within 8 days of their event were included in the study. We aimed to assess the prevalence of non-stenotic carotid disease in patients with versus without DWI-positive events, and in patients with ipsilateral DWI-positive events. A carotid-level analysis with univariable logistic regression analysis was performed to assess whether any of the assessed plaque features were associated with ipsilateral stroke.

Results: Of the 334 patients (mean age 62.7 years, 50.4% females) with available vascular neuroimaging, 153 (45.9%) had non-stenotic carotid plaques (≤50% stenosis), 174 (52.1%) had no stenosis and 7 (2.1%) patients had >50% stenosis. Of those with non-stenotic carotid plaques, 31/153 (20.3%) had evidence of DWI-positive ischemia, approximately half (15/31; 48.4%) of which was in the territory of the carotid plaque. Amongst patients with DWI-positive ischemia, non-stenotic plaques were significantly more common on the side of DWI-positive lesions [31/49 (63.3%) versus 18/49(36.7%)]. Presence of non-stenotic plaque was a risk marker for DWI-positive events (RR 1.4, 95% CI 1.1-1.8, p 0.012). On matched analysis, non-stenotic plaques were more likely on the side of DWI+ ischemia (odds ratio 1.14, 95% CI 0.36-3.70, McNemar's p value 0.80). Plaque features, including hypodensity, irregularity and greater plaque thickness were significantly associated with a higher likelihood of ipsilateral DWI+ ischemia.

Conclusion: In patients with low-risk transient or persistent neurologic events, non-stenotic carotid plaques are more common in patients with DWI-positive ischemia. Plaque features like hypodense and irregular plaque were more common with DWI-positive changes in the territory of the affected carotid.