From molecular signatures to radiomics: tailoring neurooncological strategies through forecasting of glioma growth.

OBJECTIVE: Contemporary oncological paradigms for adjuvant treatment of low- and intermediate-grade gliomas are often guided by a limited array of parameters, overlooking the dynamic nature of the disease. The authors' aim was to develop a comprehensive multivariate glioma growth model based on multicentric data, to facilitate more individualized therapeutic strategies. METHODS: Random slope models with subject-specific random intercepts were fitted to a retrospective cohort of grade II and III gliomas from the database at Kepler University Hospital (n = 191) to predict future mean tumor diameters. Deep learning-based radiomics was used together with a comprehensive clinical dataset and evaluated on an external prospectively collected validation cohort from University Hospital Zurich (n = 9). Prediction quality was assessed via mean squared prediction error. RESULTS: A mean squared prediction error of 0.58 cm for the external validation cohort was achieved, indicating very good prognostic value. The mean ± SD time to adjuvant therapy was 28.7 ± 43.3 months and 16.1 ± 14.6 months for the training and validation cohort, respectively, with a mean of 6.2 ± 5 and 3.6 ± 0.7, respectively, for number of observations. The observed mean tumor diameter per year was 0.38 cm (95% CI 0.25-0.51) for the training cohort, and 1.02 cm (95% CI 0.78-2.82) for the validation cohort. Glioma of the superior frontal gyrus showed a higher rate of tumor growth than insular glioma. Oligodendroglioma showed less pronounced growth, anaplastic astrocytoma-unlike anaplastic oligodendroglioma-was associated with faster tumor growth. Unlike the impact of extent of resection, isocitrate dehydrogenase (IDH) had negligible influence on tumor growth. Inclusion of radiomics variables significantly enhanced the prediction performance of the random slope model used. CONCLUSIONS: The authors developed an advanced statistical model to predict tumor volumes both pre- and postoperatively, using comprehensive data prior to the initiation of adjuvant therapy. Using radiomics enhanced the precision of the prediction models. Whereas tumor extent of resection and topology emerged as influential factors in tumor growth, the IDH status did not. This study emphasizes the imperative of advanced computational methods in refining personalized low-grade glioma treatment, advocating a move beyond traditional paradigms.

Feasibility, Clinical Potential, and Limitations of Trans-Burr Hole Ultrasound for Postoperative Evaluation of Chronic Subdural Hematoma: A Prospective Pilot Study.

BACKGROUND AND OBJECTIVES: Chronic subdural hematoma (CSDH) is commonly managed through burr hole surgery. Routine follow-up using computed tomography (CT) imaging is frequently used at many institutions, contributing to significant radiation exposure. This study evaluates the feasibility, safety, and reliability of trans-burr hole sonography as an alternative postoperative imaging modality, aiming to reduce radiation exposure by decreasing the frequency of CT scans. METHODS: We conducted a prospective pilot study on 20 patients who underwent burr hole surgery for CSDH. Postoperative imaging included both CT and sonographic examinations through the burr hole. We assessed the ability to measure residual subdural fluid thickness under the burr hole sonographically compared with CT, the occurrence of complications, and the potential factors affecting sonographic image quality. The Pearson correlation coefficient was used to demonstrate relationships between CT and ultrasound and axial and coronal ultrasound. RESULTS: Sonography through the burr hole was feasible in 73.5% of cases, providing measurements of residual fluid that closely paralleled CT findings, with an average discrepancy of 1.2 mm for axial and 1.4 mm for coronal sonographic views. A strong positive correlation was found between axial and coronal ultrasound (r = 0.955), CT and axial ultrasound (r = 0.936), and CT and coronal ultrasound (r = 0.920). The primary obstacle for sonographic imaging was the presence of air within the burr hole or the subdural space, which typically resolved over time after surgery. CONCLUSION: Trans-burr hole sonography emerges as a promising technique for postoperative monitoring of CSDH, with the potential to safely reduce reliance on CT scans and associated radiation exposure in selected patients. Our results support further investigation into the extended use of sonography during the follow-up phase. Prospective multicenter studies are recommended to establish the method's efficacy and to explore strategies for minimizing air presence postsurgery.

Multiparametric Analysis Combining DSC-MR Perfusion and [18F]FET-PET is Superior to a Single Parameter Approach for Differentiation of Progressive Glioma from Radiation Necrosis.

PURPOSE: Perfusion-weighted (PWI) magnetic resonance imaging (MRI) and O­(2-[18F]fluoroethyl-)-l-tyrosine ([18F]FET) positron emission tomography (PET) are both useful for discrimination of progressive disease (PD) from radiation necrosis (RN) in patients with gliomas. Previous literature showed that the combined use of FET-PET and MRI-PWI is advantageous; hhowever the increased diagnostic performances were only modest compared to the use of a single modality. Hence, the goal of this study was to further explore the benefit of combining MRI-PWI and [18F]FET-PET for differentiation of PD from RN. Secondarily, we evaluated the usefulness of cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) as previous studies mainly examined cerebral blood volume (CBV). METHODS: In this single center study, we retrospectively identified patients with WHO grades II-IV gliomas with suspected tumor recurrence, presenting with ambiguous findings on structural MRI. For differentiation of PD from RN we used both MRI-PWI and [18F]FET-PET. Dynamic susceptibility contrast MRI-PWI provided normalized parameters derived from perfusion maps (r(relative)CBV, rCBF, rMTT, rTTP). Static [18F]FET-PET parameters including mean and maximum tumor to brain ratios (TBRmean, TBRmax) were calculated. Based on histopathology and radioclinical follow-up we diagnosed PD in 27 and RN in 10 cases. Using the receiver operating characteristic (ROC) analysis, area under the curve (AUC) values were calculated for single and multiparametric models. The performances of single and multiparametric approaches were assessed with analysis of variance and cross-validation. RESULTS: After application of inclusion and exclusion criteria, we included 37 patients in this study. Regarding the in-sample based approach, in single parameter analysis rTBRmean (AUC = 0.91, p < 0.001), rTBRmax (AUC = 0.89, p < 0.001), rTTP (AUC = 0.87, p < 0.001) and rCBVmean (AUC = 0.84, p < 0.001) were efficacious for discrimination of PD from RN. The rCBFmean and rMTT did not reach statistical significance. A classification model consisting of TBRmean, rCBVmean and rTTP achieved an AUC of 0.98 (p < 0.001), outperforming the use of rTBRmean alone, which was the single parametric approach with the highest AUC. Analysis of variance confirmed the superiority of the multiparametric approach over the single parameter one (p = 0.002). While cross-validation attributed the highest AUC value to the model consisting of TBRmean and rCBVmean, it also suggested that the addition of rTTP resulted in the highest accuracy. Overall, multiparametric models performed better than single parameter ones. CONCLUSION: A multiparametric MRI-PWI and [18F]FET-PET model consisting of TBRmean, rCBVmean and PWI rTTP significantly outperformed the use of rTBRmean alone, which was the best single parameter approach. Secondarily, we firstly report the potential usefulness of PWI rTTP for discrimination of PD from RN in patients with glioma; however, for validation of our findings the prospective studies with larger patient samples are necessary.

Effect of concomitant usage of alteplase and mechanical thrombectomy for M1 middle cerebral artery occlusion on clinical outcome: a retrospective analysis of 457 patients from two centers.

Introduction: Endovascular thrombectomy (EVT) and concomitant usage of intravenous alteplase (alteplase) in large vessel occlusion stroke may produce unwanted excess intracerebral hemorrhage (ICH). Whether this applies specifically to isolated occlusion of the M1 segment of the middle cerebral artery (MCA) is unknown. Methods: A retrospective study from two tertiary thrombectomy centers. ICH was determined according to Heidelberg Bleeding Classification (HBC). Factors associated with the occurrence of ICH in EVT alone vs. EVT with alteplase were evaluated using logistic regression analysis. Factors related to the clinical outcome as determined with a modified Rankin scale (mRS) were investigated with univariate and adjusted multivariate logistic regression analysis. The interaction between clinical variables and the usage of alteplase on the occurrence of ICH was evaluated. Results: Any ICH occurred in 156/457 (34.1%) patients Class 1a bleeding in 37 (8.1%), type 2 in 45 (9.8%) Class 1c in 22 (4.8%), Class 2 in 25 (5.5%), and Class 3 (extraparenchymal) in 27 (5.9%). ICH occurred in similar frequency between alteplase-treated patients vs. EVT alone (85/262 [32%] vs. 71/195 [36%]; OR 1.19 (95% CI 0.81-1.76). After adjustment, odds for clinical outcome were lower in ICH patients (OR 0.44 [95% CI 0.25-0.74]), p = 0.002). Higher ICH rate was associated with more EVT steps (p for interaction -0.005), and usage of only stent-retriever (p for interaction =0.005). Conclusion: Utilization of alteplase alongside EVT for MCA M1 occlusion did not result in excessive ICH occurrences or clinical deterioration.

Thrombus migration in emergent M1 middle cerebral artery occlusion.

BACKGROUND AND PURPOSE: Thrombus migration (TM) is a well-established phenomenon in patients with intracranial vessel occlusion, particularly in those who receive alteplase. However, the relationship between TM, reperfusion success, and clinic-radiological outcomes is still being determined. This study aimed to describe the various outcomes in the event of TM in patients with M1 middle cerebral artery (M1 MCA) occlusion. MATERIALS AND METHODS: The study involved a retrospective analysis of patients undergoing endovascular thrombectomy (EVT) due to M1 MCA occlusion from two tertiary centers between January 2015 and December 2020. The proximal positions of thrombi were measured using a curve tool on CT or MR angiography before EVT. Subsequently, measurements were taken on angiographic imaging. Patients were grouped based on the amount of difference between the two measurements: growth (≤ - 10 mm), stability (> -10 mm and ≤ 10 mm), migration (> 10 mm), and resolution. RESULTS: A total of 463 patients (266 [57%] females, median 76 [interquartile range IQR: 65-83] years) were analyzed. Of them, 106 (22.8%) expressed any degree of TM. In multivariate ordinal regression analysis, the alteplase was significantly associated with TM (t = 2.192, p = 0.028), as was the greater interval from first imaging to angiography (t = 2.574, p = 0.010). In multivariate logistical regression analysis, the good clinical outcome measured by the modified Rankin scale (0-2) was not associated with TM status. CONCLUSIONS: Thrombus migration within the M1 MCA segment occurs in almost a quarter of patients, is associated with alteplase administration, and is mainly irrelevant to radiological and clinical outcome.

Turning the operating room into a mixed-reality environment: a prospective clinical investigation for cerebral aneurysm clipping.

OBJECTIVE: The overall aim of this study was to demonstrate the potential benefit of a novel mixed-reality-head-mounted display (MR-HMD) on the spatial orientation of surgeons. METHODS: In a prospective clinical investigation, the authors applied for the first time a new multicamera navigation technology in an operating room setting that allowed them to directly compare MR-HMD navigation to standard monitor navigation. In the study, which included 14 patients with nonruptured middle cerebral artery aneurysms, the authors investigated how intuitively and effectively surgical instruments could be guided in 5 different visual navigation conditions. RESULTS: The authors demonstrate that multicamera tracking can be reliably integrated in a clinical setting (usability score 1.12 ± 0.31). Moreover, the technology captures large volumes of the operating room, allowing the team to track and integrate different devices and instruments, including MR-HMDs. Directly comparing mixed-reality navigation to standard monitor navigation revealed a significantly improved intuition in mixed reality, leading to navigation times that were twice as fast (2.1×, p ≤ 0.01). Despite the enhanced speed, the same targeting accuracy (approximately 2.5 mm, freehand tool use) in comparison to monitor navigation could be observed. Intraoperative planning strategies with mixed reality clearly outperformed classic preoperative planning: surgeons scored the mixed-reality plan as the best trajectory in 63% of the cases (chance level 33%). CONCLUSIONS: The incorporation of mixed reality in neurosurgical operations marks a significant advancement in the field. The use of mixed reality in brain surgery enhances the spatial awareness of surgeons, enabling more instinctive and precise surgical interventions. This technological integration promises to refine the execution of complex procedures without compromising accuracy.

Distance to thrombus, ischemic lesion volume and clinical outcome after thrombectomy for M1 middle cerebral artery occlusion.

BACKGROUND: Stroke resulting from occlusion of the middle cerebral artery (MCA) can have devastating consequences, potentially leading to a loss of independence. This study aimed to investigate the relationship between the distance to the thrombus (DT) and both ischemic lesion volume (ILV) and clinical outcomes. METHODS: We retrospectively evaluated patients with thromboembolic MCA M1 segment occlusion who underwent neurovascular imaging followed by endovascular thrombectomy (EVT) at two comprehensive stroke centers over a 3-year period (2018-2020). Preinterventional computed tomography (CT) or magnetic resonance (MR) angiography was used to measure DT, defined as the distance from the carotid­T bifurcation to the proximal surface of the M1 occlusion. Postinterventional CT or MR imaging was employed to determine the ILV and clinical outcomes were assessed using the modified Rankin scale (mRS) at 3 months. RESULTS: There were 346 patients evaluated. The median DT was 9.4 mm (interquartile range, IQR 6.0-13.7 mm) and the median ILV was 13.9 ml (IQR 2.2-53.1 ml). After adjustment, an increase in DT was associated with a decrease in odds for a larger ILV (odds ratio, OR 0.96, 95% confidence interval, CI 0.92-0.99, p = 0.041). Through this association, more distal thrombi were associated with good clinical outcome (mRS 0-2; clinical outcome available in 282 patients, p = 0.018). The ILV was inversely associated with better clinical outcome OR 0.52 (95% CI 0.40-0.67). CONCLUSION: Based on the findings, DT was identified as an independent albeit weak predictor for ILV and clinical outcomes in patients with MCA M1 occlusion who underwent EVT.

Frequency and predictors of poststroke epilepsy after mechanical thrombectomy for large vessel occlusion stroke: results from a multicenter cohort study.

BACKGROUND: Poststroke epilepsy (PSE) represents an important complication of stroke. Data regarding the frequency and predictors of PSE in patients with large-vessel occlusion stroke receiving mechanical thrombectomy (MT) are scarce. Furthermore, information on acute and preexisting lesion characteristics on brain MRI has not yet been systematically considered in risk prediction of PSE. This study thus aims to assess PSE risk after acute ischemic stroke treated with MT, based on clinical and MRI features. METHODS: In this multicenter study from two tertiary stroke centers, we included consecutive acute ischemic stroke patients who had received MT for acute intracranial large vessel occlusion (LVO) between 2011 and 2017, in whom post-interventional brain MRI and long term-follow-up data were available. Infarct size, affected cerebrovascular territory, hemorrhagic complications and chronic cerebrovascular disease features were assessed on MRI (blinded to clinical information). The primary outcome was the occurrence of PSE (> 7 days after stroke onset) assessed by systematic follow-up via phone interview or electronic records. RESULTS: Our final study cohort comprised 348 thrombectomy patients (median age: 67 years, 45% women) with a median long-term follow-up of 78 months (range 0-125). 32 patients (9%) developed PSE after a median of 477 days (range 9-2577 days). In univariable analyses, larger postinterventional infarct size, infarct location in the parietal, frontal or temporal lobes and cerebral microbleeds were associated with PSE. Multivariable Cox regression analysis confirmed larger infarct size (HR 3.49; 95% CI 1.67-7.30) and presence of cerebral microbleeds (HR 2.56; 95% CI 1.18-5.56) as independent predictors of PSE. CONCLUSION: In our study, patients with large vessel occlusion stroke receiving MT had a 9% prevalence of PSE over a median follow-up period of 6.5 years. Besides larger infarct size, presence of cerebral microbleeds on brain MRI predicted PSE occurrence.

Endovascular stroke therapy outside core working hours in a nationwide stroke system.

BACKGROUND: Endovascular therapy (EVT) has been established as a major component in the acute treatment of large vessel occlusion stroke. However, it is unclear whether outcome and other treatment-related factors differ if patients are treated within or outside core working hours. METHODS: We analyzed data from the prospective nationwide Austrian Stroke Unit Registry capturing all consecutive stroke patients treated with EVT between 2016 and 2020. Patients were trichotomized according to the time of groin puncture into treatment within regular working hours (08:00-13:59), afternoon/evening (14:00-21:59) and night-time (22:00-07:59). Additionally, we analyzed 12 EVT treatment windows with equal patient numbers. Main outcome variables included favorable outcome (modified Rankin Scale scores of 0-2) 3 months post-stroke as well as procedural time metrics, recanalization status and complications. RESULTS: We analyzed 2916 patients (median age 74 years, 50.7% female) who underwent EVT. Patients treated within core working hours more frequently had a favorable outcome (42.6% vs 36.1% treated in the afternoon/evening vs 35.8% treated at night-time; p=0.007). Similar results were found when analyzing 12 treatment windows. All these differences remained significant in multivariable analysis adjusting for outcome-relevant co-factors. Onset-to-recanalization time was considerably longer outside core working hours, which was mainly explained by longer door-to-groin time (p<0.001). There was no difference in the number of passes, recanalization status, groin-to-recanalization time and EVT-related complications. CONCLUSIONS: The findings of delayed intrahospital EVT workflows and worse functional outcomes outside core working hours in this nationwide registry are relevant for optimization of stroke care, and might be applicable to other countries with similar settings.

Complication rates using balloon-expandable and self-expanding stents for the treatment of intracranial atherosclerotic stenoses : analysis of the INTRASTENT multicentric registry.

INTRODUCTION: Using balloon-expandable stents (BES) for treatment of intracranial stenoses, high inflation pressures and rigidity of the device are regarded as major drawbacks limiting feasibility and safety of the procedure. Self-expanding stents (SES) were developed to facilitate lesion access and to allow for less aggressive dilatation. We analyzed data of the INTRASTENT multicentric registry to assess whether self-expanding stents significantly reduced peri-interventional complication rates. METHODS: Records of intracranial stent procedures were entered consecutively into the registry. Datasets were divided into two groups according to the type of stent used. For outcome measurement, we chose three categories: TIA/minor stroke [modified Rankin score (mRS) <2], disabling stroke, and patient death. Clinical outcome was compared between BES and SES. We analyzed types of adverse events occurring in each group in addition. RESULTS: Of 409 atherosclerotic lesions, 254 were treated with BES and 155 with SES. Technical success rates were 97.6% and 98.7%, respectively. Adverse event rates were 4.9%, 3.7%, and 0.8% for TIA/nondisabling stroke, disabling stroke, and death in the BES group compared with 5.3%, 6.0%, and 4.0% in the SES group. The differences were not statistically significant. We observed more perforator strokes after use of BES, but thromboembolic events occurred more often in the SES treatment group. CONCLUSION: Data of the INTRASTENT registry do not support the hypothesis that introduction of SES lowered the overall complication rate of intracranial stent procedures. There might be an advantage using self-expanding stents in vessel segments with important perforating arteries.

Giant silent corticotrope pituitary adenoma in a patient with complicated clinical course.

Not required for Clinical Vignette.

Somatostatin Receptor Subtype Expression in Patients with Acromegaly and Complicated Clinical Course.

Somatostatin analogues are considered to be the first line of treatment in acromegaly. Somatostatin analogues of the first generation mainly target the somatostatin receptor (SSTR) subtype 2 and have been proven efficient in the majority of patients with acromegaly. Pasireotide was the first somatostatin analogue also substantially targeting the SSTR subtype 5. An efficient drug for Cushing's disease tailored to suboptimal-responding patients with acromegaly then became available. We immunohistochemically investigated SSTR subtypes expression in pituitary adenomas from operated acromegaly patients with clinical relapse and a complicated clinical course. Patients received pasireotide in the course of their disease. The predictive value of SSTR subtypes immunhistochemical analysis for the therapeutic response is discussed.

Comparison of PED and FRED flow diverters for posterior circulation aneurysms: a propensity score matched cohort study.

BACKGROUND: Flow diversion is a common endovascular treatment for cerebral aneurysms, but studies comparing different types of flow diverters are scarce. OBJECTIVE: To perform a propensity score matched cohort study comparing the Pipeline Embolization Device (PED) and Flow Redirection Intraluminal Device (FRED) for posterior circulation aneurysms. METHODS: Consecutive aneurysms of the posterior circulation treated at 25 neurovascular centers with either PED or FRED were collected. Propensity score matching was used to control for age, duration of follow-up imaging, adjunctive coiling, and aneurysm location, size, and morphology; previously ruptured aneurysms were excluded. The two devices were compared for the following outcomes: procedural complications, aneurysm occlusion, and functional outcome. RESULTS: A total of 375 aneurysms of the posterior circulation were treated in 369 patients. The PED was used in 285 (77.2%) and FRED in 84 (22.8%) procedures. Aneurysms treated with the PED were more commonly fusiform and larger than those treated with FRED. To account for these important differences, propensity score matching was performed resulting in 33 PED and FRED unruptured aneurysm pairs. No differences were found in occlusion status and neurologic thromboembolic or hemorrhagic complications between the two devices. The proportion of patients with favorable functional outcome was higher with FRED (100% vs 87.9%, p=0.04). CONCLUSION: Comparative analysis of PED and FRED for the treatment of unruptured posterior circulation aneurysms did not identify significant differences in aneurysm occlusion or neurologic complications. Variations in functional outcomes warrant additional investigations.

In-hospital complication rates after stent treatment of 388 symptomatic intracranial stenoses: results from the INTRASTENT multicentric registry.

BACKGROUND AND PURPOSE: Stenting is increasingly used as an adjunct to medical therapy in symptomatic intracranial stenoses. High periprocedural adverse event rates are one of the limitations of endovascular treatment. Data from the INTRASTENT multicentric registry should demonstrate in-hospital complications at the current stage of clinical development of the stent procedure. METHODS: Participating centers entered the records of all their consecutive intracranial stent procedures into the database. To determine the clinical outcome in the acute phase, we distinguished transient ischemic attack/nondisabling stroke (modified Rankin Scale <2), disabling stroke, death, and intracranial hemorrhage as clinical complications and analyzed whether they were associated with patient- or stenosis-related risk factors. RESULTS: Data from 372 patients with 388 stenoses proved 4.8% disabling strokes and 2.2% deaths. Transient or minor events were detected in 5.4% of the cases. Hemorrhagic events (3.5%) occurred more frequently after treatment of middle cerebral artery stenoses (P=0.004) and were associated with significantly higher morbidity and mortality rates. Ischemic strokes by compromise of perforating branches were detected mainly in the posterior circulation. However, the overall rate of severe adverse events was not dependent from location, degree, and morphology of the stenosis or from patient's age, gender, vascular risk factors, or type of qualifying event. CONCLUSIONS: The complication rates within the registry are within the limits of previously published data. Severe adverse events were equally distributed between potential risk groups with similar rates but different types of main complications in the anterior and posterior circulation.

Segmental innervation in lumbosacral transitional vertebrae (LSTV): a comparative clinical and intraoperative EMG study.

BACKGROUND: Despite the high prevalence of lumbosacral transitional vertebrae (LSTV), little is known about the segmental innervation in this condition. METHODS: The authors performed a prospective comparative clinical evaluation and an intraoperative electromyographic (EMG) investigation on patients with six lumbar vertebral bodies (6LVB) and on patients with five lumbar vertebrae (5LVB). First, clinical pain distribution in 80 patients (46 patients with 6LVB, 34 patients with 5LVB) with degenerative lumbar diseases were analysed between patient groups. Intraoperative EMG monitoring of five lower-limb muscles was performed. Compound muscle action potentials were obtained from 100 nerve roots of our 80 patients. RESULTS: The EMG results compared fairly to the clinical findings: 40 CMAPs from 5LVB and 60 CMAPs from 6LVB patients were compared with each other within L3 to S levels. First, there was no difference between groups in the pattern of radicular pain and myotomal innervation at the level L3/4 and L4/5 (p=0.39-1.0). Second, the nerve root stimulated at the L5/6 level compares to the S1 root in 5LVB patients; the only difference was found in a coinnervation of the biceps femoris muscle that is less frequent in 6LVB patients (p=0.02). Third, the nerve root at the L6/S level corresponds to the S1 as well as to the S2 root in 5LVB patients. CONCLUSION: Intraoperative EMG monitoring of surgically decompressed nerve roots was found to be the ideal means of unequivocal determination of segmental innervation in LSTV patients.

Comparison of Pipeline Embolization Device and Flow Re-Direction Endoluminal Device Flow Diverters for Internal Carotid Artery Aneurysms: A Propensity Score-Matched Cohort Study.

BACKGROUND: Flow diversion has become an accepted endovascular treatment modality for intracranial aneurysms. Studies comparing different types of flow diverters are currently lacking. OBJECTIVE: To perform a propensity score-matched cohort study comparing the Pipeline Embolization Device (PED; Medtronic, Dublin, Ireland) and Flow Redirection Endoluminal Device (FRED; MicroVention, Aliso Viejo, California). METHODS: Aneurysms of the internal carotid artery proximal to the communicating segment treated with PED at 2 neurovascular centers in the United States were matched with aneurysms treated in the European FRED study using propensity scoring. Aneurysms treated in the setting of subarachnoid hemorrhage were excluded from matching. Occlusion rates and complications were evaluated. RESULTS: Two hundred twenty-one internal carotid artery aneurysms were treated with PED and 282 with FRED. Propensity score matching controlling for age, sex, aneurysm size, location, number of flow diverters, and adjunctive coiling resulted in 55 matched pairs. Median angiographic follow-up was nonsignificantly longer for FRED compared to PED (12.2 vs 7.5 mo, P = .28). The rate of complete occlusion did not differ between flow diverters (80% vs 80%, P > .99). Functional outcome and complications were comparable for PED and FRED. CONCLUSION: Propensity score-matched analysis of PED and FRED for internal carotid artery aneurysms revealed comparable angiographic complete occlusion and complication rates. Whether FRED has an advantage in terms of near complete aneurysm occlusion warrants further investigation. Limitations include the retrospective design and lack of an independent assessment of radiographic outcome in a core-laboratory and functional outcomes, among others, and the results should be interpreted as such.

Evaluation of Clinical and Paraclinical Findings for the Differential Diagnosis of Autoimmune and Infectious Encephalitis.

Background: The differential diagnosis of autoimmune and infectious encephalitis is notoriously difficult. For this study, we compare the presenting clinical symptoms and paraclinical test results of autoimmune and infectious encephalitis patients. A clinical algorithm for the diagnosis of autoimmune encephalitis has recently been published. We test these Graus criteria on our cohort for diagnostic sensitivity and specificity within the first week of presentation. Methods: We included all patients seen at our department within a 10-year-period who were diagnosed with encephalitis. The discharge diagnoses served as the reference standard for testing the clinical algorithm for two conditions: use of all the clinical information available on a patient during the first week of hospital admission assuming undefined autoantibody status and microbiological test results (C1) vs. consideration of all the information available on a patient, including the results of serological and microbiological testing (C2). Results: Eighty-four patients (33 autoimmune, 51 infectious encephalitis) were included in the study. Fifty-one (17 autoimmune, 34 infectious) had a definite clinical diagnosis. The two groups differed significantly for the presence of headache, fever, epileptic seizures, and CSF cell-count at presentation. Application of the clinical algorithm resulted in a low sensitivity (58%) and very low specificity (8%) for the diagnosis of possible autoimmune encephalitis. The latter increased considerably in the subgroups of probable and definite autoimmune encephalitis. Whereas the sensitivity of the individual diagnostic categories was clearly time-dependent, the specificity rested foremost on the knowledge of the results of microbiological testing. Anti-CASPR2- and -LGI1-associated autoimmune encephalitis and tick-borne virus encephalitis presented particular diagnostic pitfalls. Conclusions: We define clinical symptoms and paraclinical test results which prove valuable for the differentiation between infectious and autoimmune encephalitis. Sensitivity and specificity of the clinical algorithm clearly depended on the amount of time passed after hospital admission and knowledge of microbiological test results. Accepting this limitation for the acute setting, the algorithm remains a valuable diagnostic aid for antibody-negative autoimmune encephalitis or in resource-poor settings. The initiation of immune therapy however should not be delayed if an autoimmune etiology is considered likely, even if the diagnostic criteria of the algorithm are not (yet) fulfilled.