Neuroradiology Journal最新文献

The safety and feasibility of using staged flow diverter (FD) for ruptured cerebral aneurysms, in which coil embolization is performed in the acute phase and FD is deployed in the subacute phase, has recently been reported. This strategy requires assuming the rupture point and performing coil embolization. Although vessel wall magnetic resonance imaging (VW-MRI) has been reported to be useful in predicting the rupture point of aneurysms, its use with staged FD has not yet been reported. We report the first case of staged FD with preoperative contrast-enhanced VW-MRI to predict the rupture point for partially thrombosed vertebral artery dissecting large aneurysm involving posterior inferior cerebellar artery (PICA) origin. This approach achieved a very good outcome, not only completely occluding the aneurysm, but also reconstructing the parent artery while maintaining the patency of the PICA.

Primary central nervous system lymphoma (PCNSL) represents 5% of malignant primary brain tumors. The clinical presentation typically includes focal neurological symptoms, increased intracranial pressure, seizures, and psychiatric symptoms. Although histological examination remains the gold standard for diagnostic confirmation, non-invasive imaging plays a crucial role for the diagnosis. In immunocompetent individuals, PCNSL usually appears as a single, well-defined, supratentorial lesion with a predilection for periventricular areas, iso- or hypointense on T1- and T2-weighted magnetic resonance imaging, with restricted diffusion, slightly increased perfusion, and homogenous gadolinium-enhancement. Differential diagnoses include high-grade glioma and pseudotumoral demyelinating disease. In immunocompromised patients, PCNSL may present as multiple lesions, with a higher likelihood of hemorrhage and necrosis and less restricted diffusion than immunocompetent individuals. Differential diagnoses include neurotoxoplasmosis, progressive multifocal leukoencephalopathy, and cerebral abscess. Atypical forms of lymphoma are characterized by extra-axial lymphoma, lymphomatosis cerebri, and intravascular lymphoma. Extra-axial lymphoma presents as single or multiple extra-axial dural lesions with diffuse leptomeningeal contrast-enhancement. Lymphomatosis cerebri appears as an infiltrative and symmetric lesion, primarily affecting deep white matter and basal ganglia, appearing hyperintense on T2-weighted imaging, without significant contrast-enhancement or perfusion changes. Intravascular lymphoma presents as multiple rounded or oval-shaped "infarct-like" lesions, located cortically or subcortically. This study aims to highlight the imaging characteristics of PCNSL, focusing on magnetic resonance imaging and its differential diagnosis.

Objective: To determine the frequency and accuracy of diffusion restriction (DR) of the retina and/or optic nerve (ON) detection on standard brain magnetic resonance diffusion-weighted imaging (DWI-MRI) in patients presenting with acute non-arteritic central retinal artery occlusion (CRAO).

Methods: This is a retrospective case-control study that includes all consecutive patients presenting to our tertiary academic center from 2013-2021 with acute non-arteritic CRAO (cases) or acute ischemic stroke syndrome (controls, age and gender-matched) that had brain MRI performed within 14 days from symptom onset. Two neurology residents (junior and senior), a vascular neurologist, and two neuroradiologists, blinded to the site of CRAO, independently reviewed the brain MRIs to assess for the presence of retina and ON DR. The consensus agreement between the two neuroradiologists was used to perform sensitivity and specificity analyses and calculate inter-rater reliability (prevalence-adjusted bias-adjusted kappa coefficient).

Results: A total of 128 patients with acute non-arteritic CRAO (mean (SD) age 69 (14) years; 50% female; median time from CRAO to DW-MRI 2 days (IQR 1-5)) and 128 age and gender-matched controls with acute cerebral ischemia were included. After the neuroradiologist consensus, DR was correctly identified in the retina or ON in 51/128 (39.8%) CRAO cases, retina alone 27.3%, ON alone 24.2%, and both retina and ON 11.7%, with almost perfect neuroradiologists' inter-rater reliability for retina (K = 0.91) and ON (K = 0.83). Among controls, the retina DR was identified in 1/128 (0.8%) and ON DR in 5/128 (3.9%). The sensitivity, specificity, positive predictive value, and negative predictive value were 28.1%, 99.2%, 97.3%, and 58.0% for retina DR, and 27.3%, 96.1%, 87.5%, and 56.9% for ON DR.

Conclusions: Though experienced neuroradiologists identified retina and ON DR with excellent inter-rater reliability, these are infrequent findings in real world CRAO practice, with excellent specificity but limited sensitivity. Prospective studies with larger cohort of patients, optimization of standardized orbit DWI-MRI protocols are needed to facilitate a more accurate and reliable identification of retina and ON DR in acute CRAO.

Introduction: Platelet function testing using serial VerifyNow P2Y12 platelet reactivity units (PRUs) is established for guiding clopidogrel antiplatelet therapy in cerebral aneurysm stenting procedures. However, for ticagrelor, the impact of serial PRU testing and the identification of safe PRU ranges remains unexplored.

Methods: Flow diversion stenting (n = 232) and stent-assisted coiling procedures (n = 83) performed 05/2017-12/2021 were reviewed. Out of these, 31 flow diversion and 18 stent-coiling procedures were performed on 44 patients using ticagrelor. Baseline demographics, ticagrelor PRUs, and clinical outcomes were assessed.

Results: Collectively, 257 ticagrelor P2Y12 PRUs were obtained. PRUs were <100 in 192/257 (74.7%) tests. Only 11/257 (4.3%) PRUs were >200. The overall median ticagrelor PRU was 38 (IQR 11-101). Among the 49 procedures, median PRUs before the procedure (25, IQR 10-67), on the day of the procedure (68, IQR 44-117), and on the day after the procedure (37, IQR 21-79) did not show the significant differences between the groups. A total of seven thromboembolic complications occurred. Median PRUs surrounding the thromboembolic complications (median 182, IQR 148-235) were significantly higher than preprocedural (p < .001), day of surgery (p < .01), and postprocedural PRUs (p < .01). All seven procedures harbored demographic, anatomic, or procedural features increasing the risk for thromboembolic complications.

Discussion: The majority of periprocedural ticagrelor PRUs were <100. PRUs at the time point of thromboembolic complications were >120. Despite procedure-complicating features in each thromboembolic case, it raises the question whether safe ticagrelor PRU levels might be lower than those commonly applied for clopidogrel.

Ecchordosis physaliphora (EP) is a benign notochordal remnant most commonly encountered in the skull base. In opposition to typical cases of its invasive counterpart, that is, chordoma, EP does not show T1-enhancement. Now, we describe three patients with EP, discovered on delayed contrast-enhanced 3D FLAIR performed for endolymphatic hydrops imaging in suspected Menière's disease. All EP cases demonstrated intense, delayed FLAIR-enhancement of the notochordal remnant. The importance of this new observation of FLAIR-enhancement in EP is threefold: (1) it may increase the detection rate of EP, (2) FLAIR-enhancement in EP should not be mistaken for T1-enhancement in chordoma, and (3) it may open a new window for future imaging studies aiming to better differentiate EP from chordoma.

Purpose: We aimed to investigate the external validation and performance of an FDA-approved deep learning model in labeling intracranial hemorrhage (ICH) cases on a real-world heterogeneous clinical dataset. Furthermore, we delved deeper into evaluating how patients' risk factors influenced the model's performance and gathered feedback on satisfaction from radiologists of varying ranks.

Methods: This prospective IRB approved study included 5600 non-contrast CT scans of the head in various clinical settings, that is, emergency, inpatient, and outpatient units. The patients' risk factors were collected and tested for impacting the performance of DL model utilizing univariate and multivariate regression analyses. The performance of DL model was contrasted to the radiologists' interpretation to determine the presence or absence of ICH with subsequent classification into subcategories of ICH. Key metrics, including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value, were calculated. Receiver operating characteristics curve, along with the area under the curve, were determined. Additionally, a questionnaire was conducted with radiologists of varying ranks to assess their experience with the model.

Results: The model exhibited outstanding performance, achieving a high sensitivity of 89% and specificity of 96%. Additional performance metrics, including positive predictive value (82%), negative predictive value (97%), and overall accuracy (94%), underscore its robust capabilities. The area under the ROC curve further demonstrated the model's efficacy, reaching 0.954. Multivariate logistic regression revealed statistical significance for age, sex, history of trauma, operative intervention, HTN, and smoking.

Conclusion: Our study highlights the satisfactory performance of the DL model on a diverse real-world dataset, garnering positive feedback from radiology trainees.

Background: The pRESET stent retriever is a self-expanding nitinol stent designed for mechanical thrombectomy in cases of large vessel occlusion during acute ischemic stroke. This systematic review and meta-analysis synthesize the available evidence on the safety and efficacy of the pRESET device.

Methods: This is a systematic review and meta-analysis study conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The electronic databases of PubMed, Embase, WoS, and Scopus were systematically reviewed from inception to 8 July 2024.

Results: A total of eight studies involving 1163 patients were included. The pooled mortality rate was 18% with a 95% CI of [12%, 25%]. The rates of any hemorrhagic complication, parenchymal hemorrhage, and subarachnoid hemorrhage were 22% with a 95% CI of [12%, 36%], 7% with a 95% CI of [4%, 13%], and 10% with a 95% CI of [5%, 17%], respectively. The rate of favorable functional outcome (modified Rankin Scale 0-2) at 90 days was 43% with a 95% CI of [34%, 52%]. Successful recanalization rates were 60% with a 95% CI of [52%, 67%] after the first pass and 90% with a 95% CI of [83%, 95%] after the final pass. Rescue devices were used in 13% with a 95% CI of [7%, 24%] of cases.

Conclusions: The pRESET stent retriever demonstrates high recanalization rates and reasonable safety outcomes in patients undergoing mechanical thrombectomy for acute ischemic stroke due to large vessel occlusion. Further randomized trials directly comparing pRESET to other stent retrievers are warranted.

Objective: This study aims to describe our experience and safety considerations associated with the use of the transulnar approach in neurointerventional procedures when radial access is not feasible.

Methods: A prospective exploratory analysis was conducted on 35 patients who underwent diagnostic or therapeutic neuroangiography via transulnar approach due to radial access limitations. Technical aspects of the transulnar approach, patient demographics, procedural details, and complications were documented. Statistical analysis was performed using SPSS Statistics software.

Results: Among the 35 procedures, the transulnar approach demonstrated a high success rate (97.14%), with only one procedural failure. Indications for transulnar access included larger ulnar artery caliber (46%), radial artery spasm (37%), severe tortuosity of the radial artery (17%), and other anatomical considerations. Complications were rare, with only two access-related complications observed: a type I hematoma and ulnar artery vasospasm. No major bleeding episodes occurred, highlighting the safety profile of transulnar access.

Conclusion: The transulnar approach represents a feasible alternative for neurointerventional procedures when radial access is not achievable. It offers high success rates and minimal complications, comparable to the radial approach. Anatomical considerations, safety profile, and patient preference support its consideration as a secondary option in neurointerventional practice. Further research and larger studies are warranted to validate its efficacy and safety in a broader patient population.

Purpose: This research seeks to investigate correlations between enlarged Perivascular Spaces (PVSs) and clinical/imaging data, such as information obtained through Doppler analysis, in a population with young and middle-age stroke. Materials and methods: We retrospectively reviewed demographics, clinical and MRI data, of 163 patients, with MRI confirmed stroke. All patients underwent ECD TSA (Eco-Color-Doppler of the Supra-aortic Trunks) and TCCD (Transcranial Eco-color-Doppler), to study extra or intracranial stenosis, presence and composition of plaques. Severity of PVS was evaluated on T2-weighted images according to the Potter scale. To identify potential predictors of PVSs, an exploratory backward stepwise ordinal regression model was developed, including clinical and Doppler US variables. Results: In the stepwise ordered logistic regression analysis with PVSs at BG (Basal Ganglia) as the outcome, hemodynamically significant stenosis in any vessel ipsilateral to the ischemic lesion displayed a significant positive association with a higher outcome value. Similar results were observed for ESUS (Embolic Stroke of Undetermined Source). Fibrolipid plaques in any vase exhibited a significant negative association. At MB (Midbrain), male patients and subjects with hypertension exhibited a higher value of PVSs. Dyslipidemia demonstrated a significant negative effect. When PVSs were investigated in the CS (Centrum Semiovale), no statistically significant association with the extent of PVSs emerged. Conclusion: These insights not only enhance our understanding of the role of PVSs in cerebrovascular health in a young and middle-age population but also highlight the potential of PVSs as a biomarker in neuroimaging studies, warranting further research to elucidate their clinical implications and underlying pathophysiological mechanisms.

Background and purpose: Mechanical thrombectomy (MT) is the treatment standard for large vessel occlusion (LVO) stroke. Under current guidelines, only patients with smaller ischemic core volumes (ICV) are eligible for MT. Thus, it is of interest to quickly estimate ICV in stroke patients. The Los Angeles Motor Scale (LAMS) is a validated tool used to assess stroke severity directly in the field. This study aims to determine whether LAMS score is also associated with ICV, as defined by the CBF <30% volume on CT perfusion imaging.

Methods: We performed a retrospective, multicenter cohort study of consecutive patients presenting with LVO stroke from 9/1/2017 to 10/1/2023. The inclusion criteria were patients with (1) stroke caused by large vessel occlusion confirmed on CTA and (2) diagnostically adequate, multimodal pretreatment CT imaging. Demographic, clinical, and imaging data was collected through manual chart review. Both univariate and multivariate analyses were applied to assess associations. A p-value <.05 was considered significant.

Results: A total of 283 patients (median age: 69, IQR: 61-78) were included in the study. On multivariate logistic regression analysis, we found that lower admission LAMS score (adjusted OR: 0.511, 95% CI: 0.313-0.834, p = .007) was independently associated with a CBF <30% volume of less than 50cc.

Conclusions: Admission LAMS is an independent predictor of a CBF <30% volume of less than 50cc. This demonstrates that LAMS can be used to estimate ICV, which will aid in the early triaging of LVO patients to thrombectomy-capable centers.