Endovascular Treatment for Acute Ischemic Stroke With or Without General Anesthesia: A Matched Comparison.

BACKGROUND: Endovascular treatment in large artery occlusion stroke reduces disability. However, the impact of anesthesia type on clinical outcomes remains uncertain. METHODS: We compared consecutive patients in the Swiss Stroke Registry with anterior circulation stroke receiving endovascular treatment with or without general anesthesia (GA). The primary outcome was disability on the modified Rankin Scale after 3 months, analyzed with ordered logistic regression. Secondary outcomes included dependency or death (modified Rankin Scale score ≥3), National Institutes of Health Stroke Scale after 24 hours, symptomatic intracranial hemorrhage with ≥4 points worsening on National Institutes of Health Stroke Scale within 7 days, and mortality. Coarsened exact matching and propensity score matching were performed to adjust for indication bias. RESULTS: One thousand two hundred eighty-four patients (GA: n=851, non-GA: n=433) from 8 Stroke Centers were included. Patients treated with GA had higher modified Rankin Scale scores after 3 months than patients treated without GA, in the unmatched (odds ratio [OR], 1.75 [1.42-2.16]; P<0.001), the coarsened exact matching (n=332-524, using multiple imputations of missing values; OR, 1.60 [1.08-2.36]; P=0.020), and the propensity score matching analysis (n=568; OR, 1.61 [1.20-2.15]; P=0.001). In the coarsened exact matching analysis, there were no significant differences in National Institutes of Health Stroke Scale after 1 day (estimated coefficient 2.61 [0.59-4.64]), symptomatic intracranial hemorrhage (OR, 1.06 [0.30-3.75]), dependency or death (OR, 1.42 [0.91-2.23]), or mortality (OR, 1.65 [0.94-2.89]). In the propensity score matching analysis, National Institutes of Health Stroke Scale after 24 hours (estimated coefficient, 3.40 [1.76-5.04]), dependency or death (OR, 1.49 [1.07-2.07]), and mortality (OR, 1.65 [1.11-2.45]) were higher in the GA group, whereas symptomatic intracranial hemorrhage did not differ significantly (OR, 1.77 [0.73-4.29]). CONCLUSIONS: This large study showed worse functional outcome after endovascular treatment of anterior circulation stroke with GA than without GA in a real-world setting. This finding appears to be independent of known differences in patient characteristics between groups.

The Use of Contrast Agents in Interventional Pain Procedures: A Multispecialty and Multisociety Practice Advisory on Nephrogenic Systemic Fibrosis, Gadolinium Deposition in the Brain, Encephalopathy After Unintentional Intrathecal Gadolinium Injection, and Hypersensitivity Reactions.

This Practice Advisory presents a comprehensive and evidence-based set of position statements and recommendations for the use of contrast media in interventional pain procedures. The advisory was established by an international panel of experts under the auspices of 11 multinational and multispecialty organizations based on a comprehensive review of the literature up to December 31, 2019. The advisory discusses the risks of using gadolinium-based contrast agents. These include nephrogenic systemic fibrosis, gadolinium brain deposition/retention, and encephalopathy and death after an unintentional intrathecal gadolinium injection. The advisory provides recommendations on the selection of a specific gadolinium-based contrast agent in patients with renal insufficiency, those who had multiple gadolinium-enhanced magnetic resonance imaging examinations, and in cases of paraspinal injections. Additionally, recommendations are made for patients who have a history of mild, moderate, or severe hypersensitivity reactions to contrast medium.

Correction to: Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry.

The name of Roy Thomas Daniel was incorrectly captured in the original manuscript.

Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry.

BACKGROUND: The treatment of ruptured posterior circulation aneurysms remains challenging despite progresses in the endovascular and neurosurgical techniques. OBJECTIVE: To provide epidemiological characterization of subjects presenting with ruptured posterior circulation aneurysms in Switzerland and thereby assessing the treatment patterns and neurological outcomes. METHODS: This is a retrospective analysis of the Swiss SOS registry for patients with aneurysmal subarachnoid hemorrhage. Patients were divided in 3 groups (upper, lower, and middle third) according to aneurysm location. Clinical, radiological, and treatment-related variables were identified and their impact on the neurological outcome was determined. RESULTS: From 2009 to 2014, we included 264 patients with ruptured posterior circulation aneurysms. Endovascular occlusion was the most common treatment in all 3 groups (72% in the upper third, 68% in the middle third, and 58.8% in the lower third). Surgical treatment was performed in 11.3%. Favorable outcome (mRS ≤ 3) was found in 56% at discharge and 65.7% at 1 year. No significant difference in the neurological outcome were found among the three groups, in terms of mRS at discharge (p = 0.20) and at 1 year (p = 0.18). High WFNS grade, high Fisher grade at presentation, and rebleeding before aneurysm occlusion (p = 0.001) were all correlated with the risk of unfavorable neurological outcome (or death) at discharge and at 1 year. CONCLUSIONS: In this study, endovascular occlusion was the principal treatment, with a favorable outcome for two-thirds of patients at discharge and at long term. These results are similar to high volume neurovascular centers worldwide, reflecting the importance of centralized care at specialized neurovascular centers.

Ruptured PICA aneurysms: presentation and treatment outcomes compared to other posterior circulation aneurysms. A Swiss SOS study.

BACKGROUND AND PURPOSE: Aneurysms of the posterior inferior cerebellar artery (PICA) are relatively uncommon and evidence is sparse about patients presenting with ruptured PICA aneurysms. We performed an analysis of the Swiss SOS national registry to describe clinical presentation, treatment pattern, and neurological outcome of patients with ruptured PICA aneurysms compared with other ruptured posterior circulation (PC) aneurysms. METHODS: This was a retrospective analysis of anonymized data from the Swiss SOS registry (Swiss Study on Aneurysmal Subarachnoid Hemorrhage; 2009-2014). Patients with ruptured PC aneurysms were subdivided into a PICA and non-PICA group. Clinical, radiological, and treatment-related variables were identified, and their impact on the neurological outcome was determined in terms of modified Rankin score at discharge and at 1 year of follow-up for the two groups. RESULTS: Data from 1864 aneurysmal subarachnoid hemorrhage patients were reviewed. There were 264 patients with a ruptured PC aneurysm. Seventy-four PICA aneurysms represented 28% of the series; clinical and radiological characteristics at admission were comparable between the PICA and non-PICA group. Surgical treatment was accomplished in 28% of patients in the PICA group and in the 4.8% of patients in the non-PICA group. No statistically significant difference was found between the two groups in terms of complications after treatment. Hydrocephalus requiring definitive shunt was needed in 21.6% of PICA patients (p = 0.6); cranial nerve deficit was present in average a quarter of the patients in both PICA and non-PICA group with no statistical difference (p = 0.3). A more favorable outcome (66.2%) was reported in the PICA group at discharge (p < 0.05) but this difference faded over time with a similar neurological outcome at 1-year follow-up (p = 0.09) between both PICA and non-PICA group. The Kaplan-Meyer estimation showed no significant difference in the mortality rate between both groups (p = 0.08). CONCLUSIONS: In the present study, patients with ruptured PICA aneurysms had a favorable neurological outcome in more than two thirds of cases, similar to patients with other ruptured PC aneurysms. Surgical treatment remains a valid option in a third of cases with ruptured PICA aneurysms.

Correction to: Ruptured PICA aneurysms: presentation and treatment outcomes compared to other posterior circulation aneurysms. A Swiss SOS study.

Incorrect authorgroup and authorname.

Dose reduction in perfusion CT in stroke patients by lowering scan frequency does not affect automatically calculated infarct core volumes.

BACKGROUND AND PURPOSE: CT Perfusion technique (CTP) is a quantitative, easily performed, accepted and reliable method for detection of ischemic brain changes. Based on calculated parameters, the size of ischemic penumbra and irreversibly damaged infarct core can be determined which helps guide treatment decisions. However, due to the dynamic nature of the CTP study, it is dose intensive. This study determines the consequences of retrospectively reducing the number of scans in the dynamic acquisition by half on the volume of the automatically calculated infarct core (non-viable tissue) and penumbra (tissue at risk) volumes. Our hypothesis was that equivalent volumetric information could be obtained at a substantial dose savings. MATERIALS AND METHODS: Fifty one consecutive patients with occlusion of M1 and/or M2 segment of the middle cerebral artery and ischemic stroke proven by follow-up MRI were included. CTP scans were first analyzed in a standard fashion and automatically generated volumes measured in milliliters were recorded in a database. A second analysis was conducted after removing every second data acquisition from the sequential CTP scans. Automatic volume measurements were repeated, recorded and compared to the initial values obtained using the full dataset. RESULTS: The two CTP protocols were statistically equivalent pertaining to automatic infarct core volume calculation but a case-by-case analysis revealed substantial overestimation in some cases. CONCLUSION: Reduction of radiation exposure in CTP without objective loss of accuracy of automatically calculated infarct core volume is feasible but might lead to clinically relevant infarct core overestimation in individual cases.

Factors associated with clinical and radiological status on admission in patients with aneurysmal subarachnoid hemorrhage.

Grading scales yield objective measure of the severity of aneurysmal subarachnoid hemorrhage and serve as to guide treatment decisions and for prognostication. The purpose of this cohort study was to determine what factors govern a patient's disease-specific admission scores in a representative Central European cohort. The Swiss Study of Subarachnoid Hemorrhage includes anonymized data from all tertiary referral centers serving subarachnoid hemorrhage patients in Switzerland. The 2009-2014 dataset was used to evaluate the impact of patient and aneurysm characteristics on the patients' status at admission using descriptive and multivariate regression analysis. The primary/co-primary endpoints were the GCS and the WFNS grade. The secondary endpoints were the Fisher grade, the presence of a thick cisternal or ventricular clot, the presence of a new focal neurological deficit or cranial nerve palsy, and the patient's intubation status. In our cohort of 1787 consecutive patients, increasing patient age by 10 years and low pre-ictal functional status (mRS 3-5) were inversely correlated with "high" GCS score (GCS ≥ 13) (OR 0.91, 95% CI 0.84-0.97 and OR 0.67, 95% CI 0.31-1.46), "low" WFNS grade (grade VI-V) (OR 1.21, 95% CI 1.04-1.20 and OR 1.47, 95% CI 0.66-3.27), and high Fisher grade (grade III-IV) (OR 1.08, 95% CI 1.00-1.17 and OR 1.54, 95% CI 0.55-4.32). Other independent predictors for the patients' clinical and radiological condition at admission were the ruptured aneurysms' location and its size. In sum, chronological age and pre-ictal functional status, as well as the ruptured aneurysm's location and size, determine the patients' clinical and radiological condition at admission to the tertiary referral hospital.

Republished: Society for Neuroscience in Anesthesiology and Critical Care expert consensus statement: Anesthetic management of endovascular treatment for acute ischemic stroke.

Literature on the anesthetic management of endovascular treatment of acute ischemic stroke (AIS) is limited. Anesthetic management during these procedures is still mostly dependent on individual or institutional preferences. Thus, the Society of Neuroscience in Anesthesiology and Critical Care (SNACC) created a task force to provide expert consensus recommendations on anesthetic management of endovascular treatment of AIS. The task force conducted a systematic literature review (up to August 2012). Because of the limited number of research articles relating to this subject, the task force solicited opinions from experts in this area. The task force created a draft consensus statement based on the available data. Classes of recommendations and levels of evidence were assigned to articles specifically addressing anesthetic management during endovascular treatment of stroke using the standard American Heart Association evidence rating scheme. The draft consensus statement was reviewed by the Task Force, SNACC Executive Committee and representatives of Society of NeuroInterventional Surgery (SNIS) and Neurocritical Care Society (NCS) reaching consensus on the final document. For this consensus statement the anesthetic management of endovascular treatment of AIS was subdivided into 12 topics. Each topic includes a summary of available data followed by recommendations. This consensus statement is intended for use by individuals involved in the care of patients with acute ischemic stroke, such as anesthesiologists, interventional neuroradiologists, neurologists, neurointensivists and neurosurgeons.

Radiolabeled Somatostatin Receptor Antagonist Versus Agonist for Peptide Receptor Radionuclide Therapy in Patients with Therapy-Resistant Meningioma: PROMENADE Phase 0 Study.

Our primary aim was to compare the therapeutic index (tumor-to-bone marrow and tumor-to-kidney absorbed-dose ratios) of the new radiolabeled somatostatin receptor antagonist [177Lu]Lu-DOTA-JR11 with the established radiolabeled somatostatin receptor agonist [177Lu]Lu-DOTATOC in the same patients with progressive, standard therapy-refractory meningioma. Methods: In this prospective, single-center, open-label phase 0 study (NCT04997317), 6 consecutive patients were included: 3 men and 3 women (mean age, 63.5 y). Patients received 6.9-7.3 GBq (standard injected radioactivity) of [177Lu]Lu-DOTATOC followed by 3.3-4.9 GBq (2 GBq/m2 × body surface area) of [177Lu]Lu-DOTA-JR11 at an interval of 10 ± 1 wk. In total, 1 [177Lu]Lu-DOTATOC and 2-3 [177Lu]Lu-DOTA-JR11 treatment cycles were performed. Quantitative SPECT/CT was done at approximately 24, 48, and 168 h after injection of both radiopharmaceuticals to calculate meningioma and organ absorbed doses as well as tumor-to-organ absorbed-dose ratios (3-dimensional segmentation approach for meningioma, kidneys, liver, bone marrow, and spleen). Results: The median of the meningioma absorbed dose of 1 treatment cycle was 3.4 Gy (range, 0.8-10.2 Gy) for [177Lu]Lu-DOTATOC and 11.5 Gy (range, 4.7-22.7 Gy) for [177Lu]Lu-DOTA-JR11. The median bone marrow and kidney absorbed doses after 1 treatment cycle were 0.11 Gy (range, 0.05-0.17 Gy) and 2.7 Gy (range, 1.3-5.3 Gy) for [177Lu]Lu-DOTATOC and 0.29 Gy (range, 0.16-0.39 Gy) and 3.3 Gy (range, 1.6-5.9 Gy) for [177Lu]Lu-DOTA-JR11, resulting in a 1.4 (range, 0.9-1.9) times higher median tumor-to-bone marrow absorbed-dose ratio and a 2.9 (range, 2.0-4.8) times higher median tumor-to-kidney absorbed-dose ratio with [177Lu]Lu-DOTA-JR11. According to the Common Terminology Criteria for Adverse Events version 5.0, 2 patients developed reversible grade 2 lymphopenia after 1 cycle of [177Lu]Lu-DOTATOC. Afterward, 2 patients developed reversible grade 3 lymphopenia and 1 patient developed reversible grade 3 lymphopenia and neutropenia after 2-3 cycles of [177Lu]Lu-DOTA-JR11. No grade 4 or 5 adverse events were observed at 15 mo or more after the start of therapy. The disease control rate was 83% (95% CI, 53%-100%) at 12 mo or more after inclusion. Conclusion: Treatment with 1 cycle of [177Lu]Lu-DOTA-JR11 showed 2.2-5.7 times higher meningioma absorbed doses and a favorable therapeutic index compared with [177Lu]Lu-DOTATOC after injection of 1.4-2.1 times lower activities. The first efficacy results demonstrated a high disease control rate with an acceptable safety profile in the standard therapy for refractory meningioma patients. Therefore, larger studies with [177Lu]Lu-DOTA-JR11 are warranted in meningioma patients.

49-year-old woman • headache and neck pain radiating to ears and eyes • severe hypertension • Dx?

► headache and neck pain radiating to ears and eyes ► severe hypertension.

Quantifying the Effects of Structured Reporting on Report Turnaround Times and Proofreading Workload in Neuroradiology.

RATIONALE AND OBJECTIVES: To assess the effects of a change from free text reporting to structured reporting on resident reports, the proofreading workload and report turnaround times in the neuroradiology daily routine. MATERIALS AND METHODS: Our neuroradiology section introduced structured reporting templates in July 2019. Reports dictated by residents during dayshifts from January 2019 to March 2020 were retrospectively assessed using quantitative parameters from report comparison. Through automatic analysis of text-string differences between report states (i.e. draft, preliminary and final report), Jaccard similarities and edit distances of reports following read-out sessions as well as after report sign-off were calculated. Furthermore, turnaround times until preliminary and final report availability to clinicians were investigated. Parameters were visualized as trending line graphs and statistically compared between reporting standards. RESULTS: Three thousand five hundred thirty-eight reports were included into analysis. Mean Jaccard similarity of resident drafts and staff-reviewed final reports increased from 0.53 ± 0.37 to 0.79 ± 0.22 after the introduction of structured reporting (p < .001). Both mean overall edits on draft reports by residents following read-out sessions (0.30 ± 0.45 vs. 0.09 ± 0.29; p < .001) and by staff radiologists during report sign-off (0.17 ± 0.28 vs. 0.12 ± 0.23, p < .001) decreased. With structured reporting, mean turnaround time until preliminary report availability to clinicians decreased by 20.7 minutes (246.9 ± 207.0 vs. 226.2 ± 224.9; p < .001). Similarly, final reports were available 35.0 minutes faster on average (558.05 ± 15.1 vs. 523.0 ± 497.3; p = .002). CONCLUSION: Structured reporting is beneficial in the neuroradiology daily routine, as resident drafts require fewer edits in the report review process. This reduction in proofreading workload is likely responsible for lower report turnaround times.

Ultrasonography-guided radiofrequency ablation of vascular malformations-The moving shot technique.

Purpose: To describe a novel ultrasound-guided technique for percutaneous radiofrequency ablation of vascular malformations-the "moving shot technique." Methods: Preliminary observational cohort study, conducted from June 1, 2019, to January 31, 2021, including all consecutive patients diagnosed with vascular malformations who were treated with ultrasound-guided radiofrequency ablation using the moving shot technique. Only patients who had undergone at least one unsuccessful previous treatment were included (sclerotherapy with ethanol/aethoxysklerol or embolization/surgery). Results: Eight patients with a median age of 22 years (interquartile range, 13-31) were included. Patients had different vascular malformations consisting of 1 arteriovenous malformation, 4 venous malformations, and 1 each a mixed venous-lymphatic malformation, a glomuvenous malformation and a FAVA (fibroadipose vascular anomaly). Malformations were located at the limbs in 5 patients (62.5%), the subcutaneous/intramuscular tissue of the body in 2 patients (25%) and at the chin in 1 patient (12.5%). Clinical symptoms were pain in 8 patients (100%), swelling in 6 patients (75%), and partial immobility in 4 patients (50%). All patients showed an improvement of clinical symptoms after treatment with 7 (87.5%) being completely asymptomatic and 1 (12.5%) showing improvement of immobility and pain. No procedural complications, such as nerve damage or skin burns occurred. Conclusion: The moving shot technique using ultrasonography-guided radiofrequency ablation is a promising technique for the interventional treatment of vascular malformations and should be validated in multicenter-approaches.

Initial Experience with the Solitaire X 3 mm Stent Retriever for the Treatment of Distal Medium Vessel Occlusions.

Endovascular therapy (EVT) is the standard treatment for ischemic stroke caused by a large vessel occlusion (LVO). The effectiveness of EVT for distal medium vessel occlusions (MDVOs) is still uncertain, but newer, smaller devices show potential for EVT in MDVOs. The new Solitaire X 3 mm device offers a treatment option for MDVOs. Our study encompassed consecutive cases of primary and secondary MDVOs treated with the Solitaire X 3 mm stent-retriever as first-line EVT device between January and December 2022 at 12 European stroke centers. The primary endpoint was a first-pass near-complete or complete reperfusion, defined as a modified treatment in cerebral infarction (mTICI) score of 2c/3. Additionally, we examined reperfusion results, National Institutes of Health Stroke Scale (NIHSS) scores at 24 h and discharge, device malfunctions, complications and procedural technical parameters. Sixty-eight patients (38 women, mean age 72 ± 14 years) were included in our study. Median NIHSS at admission was 11 (IQR 6-16). In 53 (78%) cases, a primary combined approach was used as the frontline technique. Among all enrolled patients, first-pass mTICI 2c/3 was achieved in 22 (32%) and final mTICI 2c/3 in 46 (67.6%) patients after a median of 1.5 (IQR 1-2) passes. Final reperfusion mTICI 2b/3 was observed in 89.7% of our cases. We observed no device malfunctions. Median NIHSS at discharge was 2 (IQR 0-4), and no symptomatic intracranial hemorrhages were reported. Based on our analysis, the utilization of the Solitaire X 3 mm device appears to be both effective and safe for performing EVT in cases of MDVO stroke.

Impact of Very Small Aneurysm Size and Anterior Communicating Segment Location on Outcome after Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Very small anterior communicating artery aneurysms (vsACoA) of <5 mm in size are detected in a considerable number of patients with aneurysmal subarachnoid hemorrhage (aSAH). Single-center studies report that vsACoA harbor particular risks when treated. OBJECTIVE: To assess the clinical and radiological outcome(s) of patients with aSAH diagnosed with vsACoA after aneurysm treatment and at discharge. METHODS: Information on n = 1868 patients was collected in the Swiss Subarachnoid Hemorrhage Outcome Study registry between 2009 and 2014. The presence of a new focal neurological deficit at discharge, functional status (modified Rankin scale), mortality rates, and procedural complications (in-hospital rebleeding and presence of a new stroke on computed tomography) was assessed for vsACoA and compared with the results observed for aneurysms in other locations and with diameters of 5 to 25 mm. RESULTS: This study analyzed n = 1258 patients with aSAH, n = 439 of which had a documented ruptured ACoA. ACoA location was found in 38% (n = 144/384) of all very small ruptured aneurysms. A higher in-hospital bleeding rate was found in vsACoA compared with non-ACoA locations (2.8 vs 2.1%), especially when endovascularly treated (2.1% vs 0.5%). In multivariate analysis, aneurysm size of 5 to 25 mm, and not ACoA location, was an independent risk factor for a new focal neurological deficit and a higher modified Rankin scale at discharge. Neither very small aneurysm size nor ACoA location was associated with higher mortality rates at discharge or the occurrence of a peri-interventional stroke. CONCLUSION: Very small ruptured ACoA have a higher in-hospital rebleeding rate but are not associated with worse morbidity or mortality.

Incidence and outcome of perforations during medium vessel occlusion compared with large vessel occlusion thrombectomy.

BACKGROUND: Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation. METHODS: In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0-2) and all-cause mortality at 90 days. Binomial test, chi-squared test and t-test for unpaired samples were used for statistical analysis. RESULTS: During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%, p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%, p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation. CONCLUSIONS: In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

Utilization of Artificial Intelligence-based Intracranial Hemorrhage Detection on Emergent Noncontrast CT Images in Clinical Workflow.

Authors implemented an artificial intelligence (AI)-based detection tool for intracranial hemorrhage (ICH) on noncontrast CT images into an emergent workflow, evaluated its diagnostic performance, and assessed clinical workflow metrics compared with pre-AI implementation. The finalized radiology report constituted the ground truth for the analysis, and CT examinations (n = 4450) before and after implementation were retrieved using various keywords for ICH. Diagnostic performance was assessed, and mean values with their respective 95% CIs were reported to compare workflow metrics (report turnaround time, communication time of a finding, consultation time of another specialty, and turnaround time in the emergency department). Although practicable diagnostic performance was observed for overall ICH detection with 93.0% diagnostic accuracy, 87.2% sensitivity, and 97.8% negative predictive value, the tool yielded lower detection rates for specific subtypes of ICH (eg, 69.2% [74 of 107] for subdural hemorrhage and 77.4% [24 of 31] for acute subarachnoid hemorrhage). Common false-positive findings included postoperative and postischemic defects (23.6%, 37 of 157), artifacts (19.7%, 31 of 157), and tumors (15.3%, 24 of 157). Although workflow metrics such as communicating a critical finding (70 minutes [95% CI: 54, 85] vs 63 minutes [95% CI: 55, 71]) were on average reduced after implementation, future efforts are necessary to streamline the workflow all along the workflow chain. It is crucial to define a clear framework and recognize limitations as AI tools are only as reliable as the environment in which they are deployed. Keywords: CT, CNS, Stroke, Diagnosis, Classification, Application Domain © RSNA, 2022.

Applications of time-resolved MR angiography.

OBJECTIVE: The purpose of this essay is to describe the basic principles behind contrast-enhanced time-resolved MR angiography (MRA) performed with the time-resolved imaging with stochastic trajectories technique and to show examples of the versatile applications of this technique in the evaluation of pathologic conditions throughout the body. CONCLUSION: Time-resolved MR angiography is a versatile technique for vascular imaging throughout the body. It can be used to answer a variety of clinical questions; to acquire diagnostically useful information, even about complicated vascular lesions; and to overcome many of the limitations of bolus-chase contrast-enhanced MR angiography. The technique is particularly useful when the arterial arrival time is uncertain, the patient is freely breathing, or contrast dynamics are critical to a diagnosis.