Clinical Neuroradiology最新文献

Purpose: Emergent intracranial stenting (EICS) has demonstrated efficacy in managing intracranial stenosis in patients undergoing mechanical thrombectomy (MT) for acute ischemic stroke. However, an optimal pharmacological regimen balancing thrombosis prevention and hemorrhagic risk following stent deployment remains undefined. This study aimed to assess the safety and efficacy of prophylactic low-dose intra-arterial Eptifibatide following EICS.

Methods: This single-center retrospective study included 57 consecutive patients who underwent EICS following MT due to an underlying intracranial stenosis. Patients received intravenous heparin and Aspirin pre-stenting, followed by prophylactic low-dose intra-arterial Eptifibatide post-stenting. Univariate and multivariable logistic regression analyses were conducted to identify factors associated with 90-day functional outcomes, categorized as favorable (modified Rankin Scale [mRS] 0-2) and non-favorable (mRS 3-6).

Results: Among 57 patients who underwent EICS, 93.0% (n = 53) received a balloon-mounted coronary stent. Successful recanalization (TICI 2b/3) was achieved in 93.0% of cases. Intracranial hemorrhage was detected in 8.8% within 24 h post-procedure. The median mRS score at 90 days was 3.5 (IQR 1-6), with 40.4% of patients achieving favorable functional outcomes (mRS 0-2). Advanced age was independently associated with a non-favorable functional prognosis (OR = 1.06, 95% CI: 1.00-1.11, P = 0.034).

Conclusions: In cases of MT requiring EICS, the administration of low-dose intra-arterial Eptifibatide immediately post-stenting, in addition to post-procedure dual anti-platelet therapy, demonstrated high recanalization rates with a favorable safety profile.

Background and purpose: Endovascular thrombectomy is now the standard of care for large vessel occlusion acute ischemic stroke. However, acute stroke due to medium-vessel occlusions often result in unfavorable outcomes, and guidelines for thrombectomy are lacking. Moreover, nearly all clinical data and thrombectomy trials are based on biplane angiography systems. This study aims to compare the safety and efficacy of stroke thrombectomy procedures performed on single-plane versus biplane angiography systems in patients presenting with medium-vessel occlusions of the middle cerebral artery.

Materials and methods: This retrospective study included consecutive patients with acute ischemic stroke due to primary middle cerebral artery medium-vessel occlusions treated with thrombectomy between 7/1/2020 and 8/1/2022 at a single high-volume practice. Patients were dichotomized into those treated on single plane and biplane systems. Demographic, procedural, clinical and follow-up characteristics were compared.

Results: Among the 149 patients included, 44 underwent thrombectomy on single-plane systems, and 93 on biplane systems. No significant differences were detected in rates of good functional outcomes (mRS < 2; SP 54% vs BP 42%, p = 0.19), successful recanalization (TICI ≥ 2B; SP 91% vs BP 86%, p = 0.77), intra-procedural vascular injury (SP 0% vs BP 3%; p = 0.56), or time from groin puncture to reperfusion (SP 25 min vs BP 27 min; p = 0.97). No significant differences were detected in peri-procedural complications, or symptomatic intracerebral hemorrhage.

Conclusion: Thrombectomy for middle cerebral artery medium-vessel occlusions performed on single-plane angiography systems is as safe and efficacious as biplane procedures. Our results may have implications for increasing access to care, especially in regions with limited resources.

Background: The susceptibility vessel sign (SVS) on baseline MRI in acute ischemic stroke patients has been associated with better outcomes post-thrombectomy. This study aimed to investigate whether the presence of the SVS modifies the treatment effect of intravenous thrombolysis plus endovascular thrombectomy (IVT + EVT) versus thrombectomy alone (EVT alone).

Methods: In this secondary analysis of the SWIFT DIRECT trial, comparing IVT + EVT versus EVT alone, treatment effect and its heterogeneity were assessed with rates of pre-interventional reperfusion (eTICI 2a-3) and successful post-interventional reperfusion (eTICI of 2b-3) according to the SVS status using adjusted multivariable logistic regression. Secondary objectives were to analyze whether the presence of SVS or its individual characteristics (location, length, width, overestimation ratio, two-layered sign) were associated with outcomes.

Results: 197 of the initial 408 trial participants were included in this secondary analysis, of which 52% received IVT + EVT. SVS was present in 92% of the participants (n = 181). There was no evidence for treatment effect heterogeneity regarding the post-interventional radiological and clinical effects of IVT + EVT versus EVT alone with strata of SVS. In SVS+ participants, IVT favored pre-interventional reperfusion (aOR 7.95, 95% CI 1.42-44.46), whereas in SVS-patients, it did not (P for interaction = 0.02). The individual SVS characteristics showed no significant associations with outcomes.

Conclusion: Presence of SVS does not seem to modify the effect of IVT + EVT versus EVT alone. In SVS+ patients, IVT might improve pre-interventional reperfusion. There is insufficient evidence to recommend using SVS to inform IVT decisions prior to EVT.

Purpose: In vitro differentiation of iodine and tantalum-based liquid embolics post-embolization can be achieved using spectral computed tomography. This study evaluates the in vivo ability of clinical photon-counting computed tomography (PCD-CT) to distinguish these embolic agents in patients undergoing endovascular treatments for cerebrovascular and spinal pathologies.

Methods: This retrospective study included 25 patients treated between April 2021 and March 2024, who underwent PCD-CT imaging post-embolization for intracranial arteriovenous malformations (AVM), dural arteriovenous fistulas (dAVF), spinal tumors, or middle meningeal artery (MMA) embolization for chronic subdural hematomas (cSDH). Imaging analysis involved iterative reconstruction, using conventional images (CI), iodine maps (IM), and virtual non-contrast (VNC) series. Two blinded neuroradiologists assessed the suppression quality of the embolic agents on a Likert scale.

Results: Of the 25 patients, 22 underwent intracranial and 3 spinal embolizations. The differentiation between iodine and tantalum-based embolics achieved 92% accuracy for reader 1 and 88% for reader 2, with a Cohen's kappa coefficient of 0.92 indicating high inter-reader agreement. Iodine-based agents were moderately suppressed, whereas tantalum-based agents exhibited superior suppression. Errors arose from mistaking suppressed platinum coils for tantalum-based embolics. Hemorrhage detection accuracy was high, with a Cohen's kappa of 0.92.

Conclusions: PCD-CT effectively differentiates between iodine- and tantalum-based embolics in vivo, demonstrating high diagnostic accuracy and inter-reader reliability. This capability facilitates improved post-procedural assessment and may enhance the management of endovascularly treated patients by reducing imaging artifacts and aiding in hemorrhage detection.

Objectives: MRI is essential for monitoring multiple sclerosis (MS). Contrast-enhanced T1-weighted imaging (T1WI+C) detects active inflammatory lesions indicating blood-brain barrier breakdown and is relevant for disease monitoring and treatment optimization. Susceptibility-weighted imaging (SWI) may be included in the imaging protocol for detecting MS-specific features, such as the presence of central veins or paramagnetic rim lesions. However, post-contrast SWI (SWI+C) has an inherent "T1 shine-through effect" that enables the visualization of contrast-enhancing lesions. This study evaluates whether SWI+C in addition to standard T1WI+C improves the detection of enhancing lesions in patients with MS.

Materials and methods: The images of 310 patients with MS who underwent a standardized MRI protocol including T1WI+C and SWI+C using a 3T scanner were retrospectively reviewed. A neuroradiologist and radiology resident independently evaluated the images obtained on T1WI+C alone and T1WI+C plus SWI+C. The efficacy of T1WI+C alone was compared with that of T1WI+C plus SWI+C for detecting active enhancing MS lesions.

Results: The neuroradiologist detected 117 lesions on T1WI+C and 123 lesions on T1WI+C plus SWI+C. The resident detected 108 lesions on T1WI+C and 121 lesions on T1WI+C plus SWI+C. The interobserver agreement improved from 0.981 to 1.00 with the addition of SWI+C.

Conclusion: Adding SWI+C to standard T1WI+C consistently enhances the detection of active enhancing inflammatory MS lesions and the interobserver agreement. If standardized, this combined approach may allow for earlier detection of disease activity and improve monitoring of MS progression, potentially leading to optimized treatment decisions and improved patient outcomes.

Purpose: Diffusion Weighted Imaging (DWI) represents the infarct core in acute ischemic stroke. DWI reversibility is a phenomenon reported for the anterior circulation affecting small brain areas of the white matter. This study aims to define DWI reversibility in the posterior circulation after successful recanalization of basilar artery occlusion (BAO) and its influence on patient outcome.

Methods: This was a retrospective analysis of two tertiary stroke-centers analyzing stroke patients between January 2015 and December 2022. Inclusion criteria were available MRI before and after acute stroke treatment and successful BAO recanalization. Brain areas were defined as brainstem, cerebellum and supratentorial brain areas supplied by the posterior circulation. These areas were compared in univariate analysis. Secondarily, patient outcome was compared between patients with DWI reversibility and patients without in univariate analysis with good outcome as primary endpoint (mRS 90d 0 to 2).

Results: In total, 5/28 of included patients (21.74%) showed DWI reversibility, which was exclusively found in the brainstem. The overall extent of brainstem infarction correlated better with patient outcome compared to cerebellar or supratentorial infarction (Spearman's ρ = 0.757; p < 0.001). Good outcome was more frequent in patients with DWI reversibility compared to those without (mRS 0-2, DWI+ n = 4, 80% vs. DWI- n = 6, 26%, p = 0.023).

Conclusion: DWI restriction reversibility was observed in the brainstem of acute stroke patients with BAO. In this study, patient outcome correlates stronger with the extent of brainstem infarction compared to cerebellar or supratentorial infarction.

Background: De- and acceleration traumata can cause diffuse axonal injury (DAI) in patients with traumatic brain injury (TBI). The diagnosis of DAI on CT is challenging due to the lack of structural abnormalities. Radiomics, a method from the field of artificial intelligence (AI) offers the opportunity to extract additional information from imaging data. The purpose of this work was the evaluation of the feasibility of radiomics for an improved diagnosis of DAI in comparison to conventional radiological image assessment.

Methods: CT and MR imaging was performed in 42 patients suspicious of DAI due to the clinical state, and two control groups (n = 44;42). DAI was diagnosed by experienced neuroradiologists. Radiomics features were extracted using a standardized MRI-based atlas of the predilection areas for DAI. Different MRI and CT based models were trained and validated by five-fold cross validation. Diagnostic performance was compared to the reading of two experienced radiologists and further validated in an external test dataset.

Results: The MRI and CT models showed significant differences in radiomics features between patients with DAI and controls. The developed MRI based random forest classifier yielded an accuracy of 80-90%. The best performing CT model yielded an accuracy of 88% in the training data and 70% in the external test data. The results were comparable to conventional image analysis which achieved an accuracy of 70-81% for CT-based diagnosis.

Conclusion: MRI- and CT-based radiomics analysis is feasible for the assessment of DAI. The radiomics classifier achieved equivalent performance rates as visual radiological image diagnosis. Especially a radiomics based CT classifier can be of clinical value as a screening and AI-based decision support tool for patients with TBI.

Objectives: Throughout the pandemic, it has become evident that COVID-19 should be recognized as a systemic disease that can affect the coagulation system, potentially resulting in arterial thrombotic events (ATE) with partially bulky free-floating clots. This study aimed to investigate the incidence and imaging characteristics of ATE in hospitalized patients with COVID-19 using clinical and imaging data.

Methods: From January 2020 to May 2021, databases of five German tertiary care centers were retrospectively screened for COVID-19 patients with coincidental ATE. ATE were analyzed for localization, time of occurrence, imaging characteristics, and associations with clinical data and laboratory parameters.

Results: Out of 3267 patients, 110 ATE (102 patients, mean age, 72.01 ± 15.64 years; 63 men) were observed in the presence of COVID-19 (3.1%). ATE included ischemic stroke (40%), myocardial infarction (46.4%, %), peripheral infarction (3.6%), thrombi in precerebral arteries (3.6%), mesenteric ischemia (2.7%), thrombi in the aorta (1.8%), splenic infarction (0.9%), and kidney infarction (0.9%). The median time interval between the onset of typical respiratory COVID-19 symptoms and ATE was four days (range, -5-58, negative values indicate ATE prior to symptom onset). A significant percentage of patients exhibited ATEs with an atypical free-floating appearance (10.0%) and multiple occlusions (21.2%).

Conclusion: COVID-19 is a systemic disease associated with ATE in all vascular regions, with a predilection for the heart and brain. The incidence of ATE might be higher than in comparable viral infections and ATE possibly exhibit distinct imaging features rarely seen, such as bulky free-floating clot masses and multiple occlusions. ATE occur most frequently during the first week around the COVID-19 diagnosis.

Background and purpose: Venous outflow (VO) impairment predicts unfavorable outcomes in patients with acute ischemic stroke caused by large vessel occlusion (AIS-LVO). Prolonged venous transit (PVT), a visual qualitative VO marker on CT perfusion (CTP) time to maximum (Tmax) maps, has been associated with 90-day mortality despite successful reperfusion. This study investigates the association between PVT and modified Rankin Scale (mRS) score at discharge among AIS-LVO patients who have undergone successful reperfusion.

Methods: We performed a retrospective analysis of prospectively collected data from consecutive adult AIS-LVO patients with successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b/2c/3). PVT+ was defined as Tmax ≥ 10 s in at least one of the following locations: superior sagittal sinus and/or torcula. The primary outcome was dichotomous mRS scores at discharge (favorable: mRS 0-2; unfavorable: mRS 3-6). Regression analyses were performed to assess the effect of PVT on discharge mRS.

Results: In 119 patients of median (IQR) age 71 (63-81) years, a significantly higher proportion of PVT+ patients exhibited unfavorable mRS scores compared to PVT- patients (88.8% vs. 62.7%, p = 0.004). After adjusting for age, sex, hyperlipidemia, diabetes, history of stroke or transient ischemic attack (TIA), tobacco use, administration of intravenous thrombolysis (IVT), admission National Institutes of Health Stroke Scale (NIHSS), Alberta Stroke Program Early CT (ASPECTS) score, and ischemic core volume, the PVT+ remains significantly associated with unfavorable mRS (OR = 0.231, 95%CI 0.054-0.980, p = 0.047).

Conclusions: PVT+ was significantly associated with unfavorable mRS at discharge despite successful reperfusion in AIS-LVO patients, underscoring the importance of VO impairment in short-term functional outcomes. PVT serves as a valuable adjunct imaging biomarker derived from CTP for assessing VO profiles in AIS-LVO.