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.

Fracture of a Flow Diverter in the Cervical Internal Carotid Artery Due to Eagle Syndrome.

In Eagle syndrome, elongated styloid processes may provoke internal carotid dissection and pseudoaneurysm causing stroke and data regarding possible complications or long-term results of pseudoaneurysm treatment using a flow diverter are limited. We report a case of a dissection-related pseudoaneurysm in the left cervical carotid artery treated by implantation of a flow diverter. Follow-up imaging of the flow diverter showed fracture of a continuous radiopaque marker at 3 months and fracture of a second continuous radiopaque marker at 7 months, while contrasting of the vessel was preserved. At the time of angiographic control (8 months after implantation), the flow diverter and the extracranial left internal carotid artery were occluded, and the patient did not experience any symptoms throughout the period.

Comparison of the Contour Neurovascular System and Woven EndoBridge device for treatment of wide-necked cerebral aneurysms at a bifurcation or sidewall.

OBJECTIVE: The authors compared the Contour Neurovascular System (Contour) with the Woven EndoBridge (WEB) device for the treatment of wide-necked cerebral aneurysms at a bifurcation or sidewall. METHODS: Prospective clinical and radiological data were collected for all patients treated with either the Contour or WEB at a tertiary university hospital from May 2018 to June 2022. RESULTS: In patients who had at least 3 months of follow-up data available (median patient age 60.0 [IQR 51.8-67.0] years, male/female ratio 1:1.4), the authors compared 40 aneurysms in 34 patients treated with the Contour and 30 aneurysms in 30 patients treated with the WEB. Overall, 26 middle cerebral artery, 24 anterior communicating artery, 9 basilar artery tip, 4 posterior communicating artery, 4 internal carotid artery, 1 anterior cerebral artery, 1 posterior inferior cerebellar artery, and 1 superior cerebellar artery aneurysm were treated. In the Contour cohort, complete occlusion at last follow-up was achieved for 30 aneurysms (75%) and a small neck remnant was seen in 6 aneurysms (15%), summing up to an adequate occlusion rate of 90%. One aneurysm (2.5%) had to be retreated, and 1 symptomatic thromboembolic event (2.5%) was observed with complete remission at discharge. Three adjunctive stents (10%) had to be used due to branch occlusion. In the WEB cohort, adequate occlusion was also seen in 90% of aneurysms (complete occlusion in 19 [63.3%] and remnant neck in 8 [26.7%], with a retreatment rate of 20%). Four WEBs (13.3%) needed additional stent placement due to device protrusion into a branch, 2 asymptomatic thromboembolic events (6.7%) were noted, and 1 major ischemic event (3.3%) due to M2 occlusion was noted. One patient treated with the WEB died between follow-ups of causes unrelated to the aneurysm, treatment, or device. Time from first measurement to deployment and thus total treatment time was significantly shorter in the Contour group (p = 0.004), regardless of whether a prior angiogram was available for aneurysm measurement and device sizing. CONCLUSIONS: Results for the Contour were promising, although longer follow-up is necessary to draw more solid conclusions on the utility and risk profile of this new device compared with the already widely used WEB device. Adequate occlusion at last follow-up was the same for both devices, whereas the probability of complete occlusion at last follow-up was significantly higher for the Contour, and the WEB showed a significantly higher retreatment rate. Median deployment times were significantly shorter with the Contour than the WEB.

Unilateral delayed post-hypoxic leukoencephalopathy: a case report.

BACKGROUND: Delayed post-hypoxic leukoencephalopathy is a rare entity following hypoxia. Clinical and radiological signs of delayed post-hypoxic leukoencephalopathy have not previously been reported following acute ischemic stroke. CASE PRESENTATION: We report a case of an 81-year-old Central European man who presented with a dissection-related occlusion of the left carotid artery. He showed clinical improvement immediately after endovascular stroke therapy, followed by a significant clinical and especially cognitive deterioration thereafter and a clinical recovery after several weeks. The clinical course of the patient was accompanied by morphological changes on magnetic resonance imaging characteristic of delayed post-hypoxic leukoencephalopathy; that is, strictly limited and localized unilaterally to the left anterior circulation. CONCLUSION: This case demonstrates that clinical symptoms and morphological changes on magnetic resonance imaging compatible with delayed post-hypoxic leukoencephalopathy do not necessarily only occur with global hypoxia, but can also occur in patients with a large vessel occlusion in the corresponding vascular territories.

Meningeal Metastasis Causing Chronic Subdural Hematoma in a Cancer Patient with Bilateral Papilledema and Suspected Cerebral Venous Thrombosis: A Case Report.

Meningeal metastasis has been reported as a very rare cause of chronic subdural hematoma (CSH). Here, we report a female patient who had undergone initial burr hole drainage of a CSH at an outside hospital. Postoperatively, the patient additionally suffered from visual impairment due to bilateral papilledema and the patient was eventually transferred to our neurosurgical department for additional treatment. A craniotomy was performed and due to intraoperative suspicious findings, histopathologic samples were obtained that revealed a metastasis of thus far undiagnosed triple negative breast cancer. Furthermore, the patient was suspected to have a partial cerebral venous thrombosis (CVT). Our case report addresses this extremely rare clinical constellation. We provide a detailed overview on our patient's clinical and radiologic course, and discuss the potential association of CSH with meningeal metastasis and bilateral papilledema.

Spontaneous spinal cord infarction in Austria: a two-center comparative study.

Background: Spinal cord infarction (SCI) is a neurological emergency associated with high rates of persistent neurological deficits. Knowledge about this rare but potentially treatable condition needs to be expanded. Objective: To describe the characteristics of spontaneous SCI in a large retrospective series of patients treated at two tertiary care centers in Austria. Methods: We performed a descriptive and comparative analysis of spontaneous SCI treated at the University Hospitals of Salzburg and Graz between the years 2000 and 2020. The analysis included pre- and in-hospital procedures, clinical presentation, etiology, diagnostic certainty, reperfusion therapy, and functional outcome at discharge. Results: We identified 88 cases, 61% were ascertained in the second half of the study period. The median age was 65.5 years [interquartile range (IQR) = 56-74], 51.1% were women. Anterior spinal artery infarction was the predominant syndrome (82.9%). Demographics, vascular comorbidities, and clinical presentation did not differ between the centers. The most frequent etiology and level of diagnostic certainty were distinct, with atherosclerosis (50%) and definite SCI (42%), and unknown (52.5%) and probable SCI (60%) as front runners in Salzburg and Graz, respectively. Patients arrived after a median of 258.5 min (IQR = 110-528) at the emergency room. The first magnetic resonance imaging (MRI) of the spinal cord was performed after a median of 148 min (IQR = 90-312) from admission and was diagnostic for SCI in 45%. Two patients received intravenous thrombolysis (2.2%). The outcome was poor in 37/77 (48%). Conclusion: Demographics, clinical syndromes, and quality benchmarks for spontaneous SCI were consistent at two Austrian tertiary care centers. Our findings provide the foundation for establishing standards for pre- and in-hospital care to improve outcomes.

Direct to angiography suite approaches for the triage of suspected acute stroke patients: a systematic review and meta-analysis.

BACKGROUND: Increasing evidence suggests improved time metrics leading to better clinical outcomes when stroke patients with suspected large vessel occlusion (LVO) are transferred directly to the angiography suite (DTAS) compared with cross-sectional imaging followed by transfer to the angiography suite. We performed a systematic review and meta-analysis on the efficacy and safety of DTAS approaches. METHODS: We searched Embase, Medline, Scopus, and clinicaltrials.gov for studies comparing outcomes of DTAS and conventional triage. Eligible studies were assessed for risk of bias. We performed a random-effects meta-analysis on the differences of median door-to-groin and door-to-reperfusion times between intervention and control group. Secondary outcomes included good outcome at 90 days (modified Rankin Scale ⩽ 2) rate of symptomatic intracranial hemorrhage (sICH) and mortality within 90 days. RESULTS: Eight studies (one randomized, one cluster-randomized trial and six observational studies) with 1938 patients were included. Door-to-groin and door-to-reperfusion times in the intervention group were on median 29.0 min [95% confidence interval (CI): 14.3-43.6; p < 0.001] and 32.1 min (95% CI: 15.1-49.1; p < 0.001) shorter compared with controls. Prespecified subgroup analyses for transfer (n = 1753) and mothership patients (n = 185) showed similar reductions of the door-to-groin and door-to-reperfusion times in response to the intervention. The odds of good outcome did not differ significantly between both groups but were numerically higher in the intervention group (odds ratio: 1.38, 95% CI: 0.97-1.95; p = 0.07). There was no significant difference for mortality and sICH between the groups. CONCLUSION: DTAS approaches for the triage of suspected LVO patients led to a significant reduction in door-to-groin and door-to-reperfusion times but an effect on functional outcome was not detected. The subgroup analysis showed similar results for transfer and mothership patients.Registration: This study was registered in PROSPERO (CRD42020213621).

Variability of acquisition phase of computed tomography angiography in acute ischemic stroke in a real-world scenario.

OBJECTIVES: The informative value of computed tomography angiography (CTA) depends on the contrast phase in the vessels which may differ depending on the level of local expertise. METHODS: We retrospectively measured vessel contrast density from CTA scans in patients presenting with acute ischemic stroke to a comprehensive stroke center (CSC) or to one of eight primary stroke centers (PSC). CTAs were classified into arterial or venous phases as well as into 1 of 5 phases (early arterial, peak arterial, equilibrium, peak venous, and late venous). RESULTS: Overall, n = 871 CTAs (CSC: n = 431 (49.5%); PSC: n = 440 (50.5%)) were included in the final analysis. A higher venous than arterial contrast density at the level of the circle of Willis was only rarely observed (overall n = 13 (1.5%); CSC: n = 3/431 (0.7%); PCS: n = 10/440 (2.3%); p = 0.09). CTAs acquired in the CSC showed more often an early arterial contrast phase (CSC: n = 371 (86.1%); PSC: n = 153 (34.8%), p < 0.01). Equilibrium contrast phase, i.e., a slightly stronger arterial contrast with clear venous contrast filling, was more frequent in CTAs from the PSCs (CSC: n = 6 (1.4%); PSC: n = 47 (10.7%); p < 0.01). CONCLUSIONS: Despite different technical equipment and examination protocols, the overall number of CTAs with venous contrast was low and did not differ between the CSC and the PCSs. Differences between the further differentiated contrast phases indicate potential for further improvement of CTA acquisition protocols. KEY POINTS: • Despite different technical equipment and examination protocols in the diagnostic workup of acute ischemic stroke, the total number of computed tomography angiography (CTA) with venous contrast was low (n = 13/871; 1.5%). • A higher venous than arterial contrast density at the level of the circle of Willis was not more frequent in CTAs from the centers with a high patient volume (comprehensive stroke center) compared to the hospital with lower patient volume (primary stroke centers). • Differences between the further differentiated contrast phases indicate that there is potential for further improvement of CTA acquisition protocols.

Neuroradiological emergency consultations during the first year of the COVID-19 pandemic.

BACKGROUND: Measures taking aim at minimizing the risk of coronavirus transmission and fear of infection may affect decisions to seek care for other medical emergency conditions. The purpose of this analysis was to analyze intermediate-term effects of the COVID-19 pandemic on neuroradiological emergency consultations (NECs). METHODS: We conducted an ambispective study on NEC requests to a university hospital from a teleradiological network covering 13 hospitals in Germany. Weekly NEC rates for prepandemic calendar weeks (CW) 01/2019-09/2020 were compared with rates during first COVID-19 wave (CW 10-20/2020), first loosening of restrictions (CW 21-29/2020), intensified COVID-19 testing (CW 30-39/2020) and second COVID-19 wave (CW 40-53/2020), and contrasted with COVID-19 incidence in Germany. RESULTS: A total of n = 10 810 NECs were analyzed. Prepandemic NEC rates were stable over time (median: 103, IQR: 97-115). Upon the first COVID-19 wave in Germany, NEC rates declined sharply (median: 86, IQR: 69-92; p < 0.001) but recovered within weeks. Changes in NEC rates after first loosening of restrictions (median: 109, IQR: 98-127; p = 0. 188), a phase of intensified testing (median: 111, IQR: 101-114; p = 0.434) and as of a second COVID-19 wave (median: 102, IQR: 94-112; p = 0. 462) were not significant. Likewise, patient age and gender distribution remained constant. CONCLUSION: Upon the first pandemic COVID-19 wave in Germany, NEC rates declined but recovered within weeks. It is unknown whether this recovery reflects improved medical care and test capabilities or an adjustment of the patients' behaviour.

Emergency intubation during thrombectomy for acute ischemic stroke in patients under primary procedural sedation.

BACKGROUND: Emergency intubation is an inherent risk of procedural sedation regimens for endovascular treatment (EVT) of acute ischemic stroke. We aimed to characterize the subgroup of patients, who had to be emergently intubated, to identify predictors of the need for intubation and assess their outcomes. METHODS: This is a retrospective analysis of the single-center study KEEP SIMPLEST, which evaluated a new in-house SOP for EVT under primary procedural sedation. We used descriptive statistics and regression models to examine predictors and functional outcome of emergently intubated patients. RESULTS: Twenty of 160 (12.5%) patients were emergently intubated. National Institutes of Health Stroke Scale (NIHSS) on admission, premorbid modified Rankin scale (mRS), Alberta Stroke Program Early CT Score, age and side of occlusion were not associated with need for emergency intubation. Emergency intubation was associated with a lower rate of successful reperfusion (OR, 0.174; 95%-CI, 0.045 to 0.663; p = 0.01). Emergently intubated patients had higher in-house mortality (30% vs 6.4%; p = 0.001) and a lower rate of mRS 0-2 at 3 months was observed in those patients (10.5% vs 37%, p = 0.024). CONCLUSIONS: Emergency intubation during a primary procedural sedation regimen for EVT was associated with lower rate of successful reperfusion. Less favorable outcome was observed in the subgroup of emergently intubated patients. More research is required to find practical predictors of intubation need and to determine, whether emergency intubation is safe under strict primary procedural sedation regimens for EVT.

Variability of computed tomography angiography coverage of lung parenchyma in acute stroke.

BACKGROUND: Computed tomography angiography (CTA) of the head and neck during acute ischemic stroke (AIS) usually includes visualization of lung apices. The possibility to evaluate for pulmonary changes, e.g. peripheral ground-glass and consolidative opacities suggestive of coronavirus disease 2019 (COVID-19)-related pneumonia, depends on the area of the lung covered by CTA. METHODS: We performed an analysis of a real-world scenario assessing the variability of lung coverage on CTA in patients presenting with AIS to a comprehensive stroke center (CSC) or to one of eight primary stroke centers (PSC) within a teleradiological network covered by the comprehensive stroke center in 2019. RESULTS: Our final analysis included n = 940 CTA, and in n = 573 (61%) merely lung apices were covered. In 19/940 (2%) of patients no lung tissue was covered by CTA. CTA scanning protocols in the CSC began significantly more frequently at the level of the ascending aorta (CSC: n = 180 (38.2%), PSC: n = 127 (27.1%), p-value < 0.001) and the aortic arch (CSC: n = 140 (29.7%), PSC: n = 83 (17.7%), p-value < 0.001), and by this covered less frequently the lower lobes compared to CTA acquired in one of the PSC. CONCLUSIONS: In our pre-COVID-19 pandemic representative stroke patient cohort, CTA for AIS covered most often only lung apices. In 37% of the patients CTA visualized at least parts of the lower lobes, the lingula or the middle lobe allowing for a more extensive assessment of the lungs.

Combined Perfusion and Permeability Imaging Reveals Different Pathophysiologic Tissue Responses After Successful Thrombectomy.

Despite successful recanalization of large-vessel occlusions in acute ischemic stroke, individual patients profit to a varying degree. Dynamic susceptibility-weighted perfusion and dynamic T1-weighted contrast-enhanced blood-brain barrier permeability imaging may help to determine secondary stroke injury and predict clinical outcome. We prospectively performed perfusion and permeability imaging in 38 patients within 24 h after successful mechanical thrombectomy of an occlusion of the middle cerebral artery M1 segment. Perfusion alterations were evaluated on cerebral blood flow maps, blood-brain barrier disruption (BBBD) visually and quantitatively on ktrans maps and hemorrhagic transformation on susceptibility-weighted images. Visual BBBD within the DWI lesion corresponded to a median ktrans elevation (IQR) of 0.77 (0.41-1.4) min-1 and was found in all 7 cases of hypoperfusion (100%), in 10 of 16 cases of hyperperfusion (63%), and in only three of 13 cases with unaffected perfusion (23%). BBBD was significantly associated with hemorrhagic transformation (p < 0.001). While BBBD alone was not a predictor of clinical outcome at 3 months (positive predictive value (PPV) = 0.8 [0.56-0.94]), hypoperfusion occurred more often in patients with unfavorable clinical outcome (PPV = 0.43 [0.10-0.82]) compared to hyperperfusion (PPV = 0.93 [0.68-1.0]) or unaffected perfusion (PPV = 1.0 [0.75-1.0]). We show that combined perfusion and permeability imaging reveals distinct infarct signatures after recanalization, indicating the severity of prior ischemic damage. It assists in predicting clinical outcome and may identify patients at risk of stroke progression.

Reasons for Failed Mechanical Thrombectomy in Posterior Circulation Ischemic Stroke Patients.

BACKGROUND AND PURPOSE: To determine reasons for failed recanalization in mechanical thrombectomy (MT) of the posterior circulation. METHODS: Retrospective single center analysis of reasons for MT failure in the posterior circulation. Failed MTs were categorized according to the reason for procedure failure in failed vascular access, failed passage of the target vessel occlusion and MT failure after passing the occluded target vessel. Patient characteristics were compared between failed and successful MT. RESULTS: Patients with failed MT (30/218 patients, 13.8%) were categorized into futile vascular access (13/30, 43.3%), abortive passage of the target vessel occlusion (6/30, 20.0%) and MT failure after passing the vessel occlusion (11/30, 36.7%). In 188/218 (86.2%) successful MTs alternative vascular access, local intra-arterial (i.a.) thrombolysis and emergency stent-assisted PTA prevented 65 MT failures. Patients with failed MT showed a higher NIHSS at discharge, a higher pc-ASPECTS in follow-up imaging, a higher mRS 90 days after stroke onset and a high mortality rate of 77.0% (mRS at 90 days, median (IQR): 6 (6-6) vs. 4 (2-6) for successful MT, p-value < 0.001). Co-morbidities and stroke etiology were not different compared to sufficient recanalization with atherosclerotic disease as the leading stroke etiology in both groups. CONCLUSION: Failure of MT in posterior circulation ischemic stroke patients is associated with a high mortality rate. Reasons for MT failure are diverse with futile vascular access and MT failure after passing the vessel occlusion as the leading causes. Alternative vascular access, local i.a. thrombolysis and stent-assisted PTA can prevent MT failure.

Multimodal Predictive Modeling of Endovascular Treatment Outcome for Acute Ischemic Stroke Using Machine-Learning.

BACKGROUND AND PURPOSE: This study assessed the predictive performance and relative importance of clinical, multimodal imaging, and angiographic characteristics for predicting the clinical outcome of endovascular treatment for acute ischemic stroke. METHODS: A consecutive series of 246 patients with acute ischemic stroke and large vessel occlusion in the anterior circulation who underwent endovascular treatment between April 2014 and January 2018 was analyzed. Clinical, conventional imaging (electronic Alberta Stroke Program Early CT Score, acute ischemic volume, site of vessel occlusion, and collateral score), and advanced imaging characteristics (CT-perfusion with quantification of ischemic penumbra and infarct core volumes) before treatment as well as angiographic (interval groin puncture-recanalization, modified Thrombolysis in Cerebral Infarction score) and postinterventional clinical (National Institutes of Health Stroke Scale score after 24 hours) and imaging characteristics (electronic Alberta Stroke Program Early CT Score, final infarction volume after 18-36 hours) were assessed. The modified Rankin Scale (mRS) score at 90 days (mRS-90) was used to measure patient outcome (favorable outcome: mRS-90 ≤2 versus unfavorable outcome: mRS-90 >2). Machine-learning with gradient boosting classifiers was used to assess the performance and relative importance of the extracted characteristics for predicting mRS-90. RESULTS: Baseline clinical and conventional imaging characteristics predicted mRS-90 with an area under the receiver operating characteristics curve of 0.740 (95% CI, 0.733-0.747) and an accuracy of 0.711 (95% CI, 0.705-0.717). Advanced imaging with CT-perfusion did not improved the predictive performance (area under the receiver operating characteristics curve, 0.747 [95% CI, 0.740-0.755]; accuracy, 0.720 [95% CI, 0.714-0.727]; P=0.150). Further inclusion of angiographic and postinterventional characteristics significantly improved the predictive performance (area under the receiver operating characteristics curve, 0.856 [95% CI, 0.850-0.861]; accuracy, 0.804 [95% CI, 0.799-0.810]; P<0.001). The most important parameters for predicting mRS 90 were National Institutes of Health Stroke Scale score after 24 hours (importance =100%), premorbid mRS score (importance =44%) and final infarction volume on postinterventional CT after 18 to 36 hours (importance =32%). CONCLUSIONS: Integrative assessment of clinical, multimodal imaging, and angiographic characteristics with machine-learning allowed to accurately predict the clinical outcome following endovascular treatment for acute ischemic stroke. Thereby, premorbid mRS was the most important clinical predictor for mRS-90, and the final infarction volume was the most important imaging predictor, while the extent of hemodynamic impairment on CT-perfusion before treatment had limited importance.

Direct Transfer to Angio-Suite Versus Computed Tomography-Transit in Patients Receiving Mechanical Thrombectomy: A Randomized Trial.

BACKGROUND AND PURPOSE: To quantify workflow metrics in patients receiving stroke imaging (noncontrast-enhanced computed tomography [CT] and CT-angiography) in either a computed-tomography scanner suite (CT-Transit [CTT]) or an angio-suite (direct transfer to angio-suite-[DTAS]-using flat-panel CT) before undergoing mechanical thrombectomy. METHODS: Prospective, single-center investigator initiated randomized controlled trial in a comprehensive stroke center focusing on time from imaging to groin puncture (primary end point) and time from hospital admission to final angiographic result (secondary end point) in patients receiving mechanical thrombectomy for anterior circulation large vessel occlusion after randomization to the CTT or DTAS pathway. RESULTS: The trial was stopped early after the enrollment of n=60 patients (CTT: n=34/60 [56.7 %]; DTAS: n=26/60 [43.3%]) of n=110 planned patients because of a preplanned interim analysis. Time from imaging to groin puncture was shorter in DTAS-patients (in minutes, median [interquartile range]: CTT: 26 [23-32]; DTAS: 19 [15-23]; P value: 0.001). Time from hospital admission to stroke imaging was shorter in patients randomized to DTAS (CTT: 12 (7-18); DTAS: 21 (15-25), P value: 0.007). Time from hospital admission to final angiographic reperfusion was comparable between patient groups (CTT: 78 [58-92], DTAS: 80 [66-118]; P value: 0.067). CONCLUSIONS: This trial showed a reduction in time from imaging to groin-puncture when patients are transferred directly to the angiosuite for advanced stroke-imaging compared with imaging in a CT scanner suite. This time saving was outweighed by a longer admission to imaging time and could not translate into a shorter time to final angiographic reperfusion in this trial.

Radiation exposure in endovascular stroke treatment of acute basilar artery occlusions-a matched-pair analysis.

PURPOSE: To determine the radiation exposure in endovascular stroke treatment (EST) of acute basilar artery occlusions (BAO) and compare it with radiation exposure of EST for embolic middle cerebral artery occlusions (MCAO). METHODS: In this retrospective analysis of an institutional review board-approved prospective stroke database of a comprehensive stroke center, we focused on radiation exposure (as per dose area product in Gy × cm2, median (IQR)), procedure time, and fluoroscopy time (in minutes, median [IQR]) in patients receiving EST for BAO. Patients who received EST for BAO were matched case by case with patients who received EST for MCAO according to number of thrombectomy attempts, target vessel reperfusion result, and thrombectomy technique. RESULTS: Overall 180 patients (n = 90 in each group) were included in this analysis. General anesthesia was conducted more often during EST of BAO (BAO: 75 (83.3%); MCAO: 18 (31.1%), p < 0.001). Procedure time (BAO: 31 (20-43); MCAO: 27 (18-38); p value 0.226) and fluoroscopy time (BAO: 29 (20-59); MCAO: 29 (17-49), p value 0.317) were comparable. Radiation exposure was significantly higher in patients receiving EST for BAO (BAO: 123.4 (78.7-204.2); MCAO: 94.3 (65.5-163.7), p value 0.046), which represents an increase by 23.7%. CONCLUSION: Endovascular stroke treatment of basilar artery occlusions is associated with a higher radiation exposure compared with treatment of middle cerebral artery occlusions.

Radiation exposure per thrombectomy attempt in modern endovascular stroke treatment in the anterior circulation.

OBJECTIVE: To quantify radiation exposure (RE) of endovascular stroke treatment (EST) in the anterior circulation per thrombectomy attempt and determine causes for interventions associated with high RE. METHODS: A retrospective single-center study of an institutional review board-approved stroke database of patients receiving EST for large vessel occlusions in the anterior circulation between January 2013 and April 2018 to evaluate reference levels (RL) per thrombectomy attempt. ESTs with RE above the RL were analyzed to determine causes for high RE. RESULTS: Overall, n = 544 patients (occlusion location, M1 and M2 segments of the middle cerebral artery 53.5% and 27.2%, carotid artery 17.6%; successful recanalization rate 85.7%) were analyzed. In the overall population, DAP (in Gy cm2, median (IQR)) was 113.7 (68.9-181.7) with a median fluoroscopy time of 31 min (IQR, 17-53) and a median of 2 (IQR, 1-4) thrombectomy attempts. RE increased significantly with every thrombectomy attempt (DAP1, 68.7 (51.2-106.8); DAP2, 106.4 (84.8-115.6); p value1vs2, < 0.001; DAP3, 130.2 (89.1-183.6); p value2vs3, 0.044; DAP4, 169.9 (128.4-224.1); p value3vs4, 0.001; and DAP5, 227.6 (146.3-294.6); p value4vs5, 0.019). Procedures exceeding the 90th percentile of the attempt-dependent radiation exposure level were associated with procedural complications (n = 17/52, 29.8%) or a difficult vascular access (n = 8/52, 14%). CONCLUSIONS: Radiation exposure in endovascular stroke treatment is depending on the number of thrombectomy attempts. Radiation exposure doubles when three attempts and triples when five attempts are necessary compared with single-maneuver interventions. Procedural complications and difficult vascular access were associated with a high radiation exposure in this collective. KEY POINTS: • Radiation exposure of endovascular stroke treatment (EST) is dependent on the number of thrombectomy attempts. • Reference levels as means for quality control in hospitals performing endovascular stroke treatment should be defined by the number of thrombectomy attempts-we suggest 107 Gy cm2, 156 Gy cm2, 184 Gy cm2, 244 Gy cm2, and 295 Gy cm2 for 1 to 5 maneuvers, respectively, for EST of the anterior circulation • Cases with high rates of radiation exposure are associated with periprocedural complications and difficult anatomical access as a probable cause for a high radiation exposure.