Introduction: Computed tomography perfusion (CTP) is variably considered to assess eligibility for endovascular thrombectomy (EVT) in acute ischemic (AIS) stroke patients. Although CTP is recommended for patient selection in later (6–24 h) time window, it is currently not recommended in the earlier (0–6 h) time window and the costs and health effects of including CTP for EVT selection remain unknown. We aim to estimate the costs and health effects of using CTP for EVT selection in AIS patients compared to conventional selection. Patients and methods: CLEOPATRA is a healthcare evaluation study using clinical and imaging data from multiple, prospective EVT trials and registries in both the earlier and later time windows. To study the long-term health and cost effects, we will construct a (“Markov”) health state transition model simulating the clinical outcome over a 5-year follow-up period for CTP-based and conventional selection for EVT. Clinical data acquired within the current study and estimates from the literature will be used as input for probabilities of events, costs, and Quality-Adjusted Life Years (QALYs) per modified Rankin Scale (mRS) subscore. Primary outcome for the cost-effectiveness analysis will be the Incremental Cost-Effectiveness Ratio (ICER) in terms of costs per QALY gained over the simulated follow-up period. Study outcomes: Outcome measures will be reported as cumulative values over a 5-year follow-up period. Discussion: This study will provide preliminary insight into costs and health effects of including CTP in the selection for EVT for AIS patients, presenting between 0 and 24 h after time last known well. The results may be used to develop recommendations and inform further implementation projects and studies.

Background: It is unknown if ambulance paramedics adequately assess neurological deficits used for prehospital stroke scales to detect anterior large-vessel occlusions. We aimed to compare prehospital assessment of these stroke-related deficits by paramedics with in-hospital assessment by physicians. Methods: We used data from 2 prospective cohort studies: the LPSS (Leiden Prehospital Stroke Study) and PRESTO study (Prehospital Triage of Patients With Suspected Stroke). In both studies, paramedics scored 9 neurological deficits in stroke code patients in the field. Trained physicians scored the National Institutes of Health Stroke Scale (NIHSS) at hospital presentation. Patients with transient ischemic attack were excluded because of the transient nature of symptoms. Spearman rank correlation coefficient (r s ) was used to assess correlation between the total prehospital assessment score, defined as the sum of all prehospital items, and the total NIHSS score. Correlation, sensitivity and specificity were calculated for each prehospital item with the corresponding NIHSS item as reference. Results: We included 2850 stroke code patients. Of these, 1528 had ischemic stroke, 243 intracranial hemorrhage, and 1079 stroke mimics. Correlation between the total prehospital assessment score and NIHSS score was strong (r s =0.70 [95% CI, 0.68–0.72]). Concerning individual items, prehospital assessment of arm (r s =0.68) and leg (r s =0.64) motor function correlated strongest with corresponding NIHSS items, and had highest sensitivity (arm 95%, leg 93%) and moderate specificity (arm 71%, leg 70%). Neglect (r s =0.31), abnormal speech (r s =0.50), and gaze deviation (r s =0.51) had weakest correlations. Neglect and gaze deviation had lowest sensitivity (52% and 66%) but high specificity (84% and 89%), while abnormal speech had high sensitivity (85%) but lowest specificity (65%). Conclusions: The overall prehospital assessment of stroke code patients correlates strongly with in-hospital assessment. Prehospital assessment of neglect, abnormal speech, and gaze deviation differed most from in-hospital assessment. Focused training on these deficits may improve prehospital triage.

Purpose Intravenous alteplase (IVT) prior to endovascular treatment (EVT) is neither superior nor noninferior to EVT alone in acute ischemic stroke patients. We aim to assess whether the effect of IVT prior to EVT differs according to CT perfusion (CTP)–based imaging parameters. Methods In this retrospective post hoc analysis, we included patients from the MR CLEAN-NO IV with available CTP data. CTP data were processed using syngo.via (version VB40). We performed multivariable logistic regression to obtain the effect size estimates (adjusted common odds ratio a[c]OR) on 90-day functional outcome (modified Rankin Scale [mRS]) and functional independence (mRS 0-2) for CTP parameters with two-way multiplicative interaction terms between IVT administration and the studied parameters. Results In 227 patients, median CTP-estimated core volume was 13 (IQR 5–35) mL. The treatment effect of IVT prior to EVT on outcome was not altered by CTP-estimated ischemic core volume, penumbral volume, mismatch ratio, and presence of a target mismatch profile. None of the CTP parameters was significantly associated with functional outcome after adjusting for confounders. Conclusion In directly admitted patients with limited CTP-estimated ischemic core volumes who presented within 4.5 h after symptom onset, CTP parameters did not statistically significantly alter the treatment effect of IVT prior to EVT. Further studies are needed to confirm these results in patients with larger core volumes and more unfavorable baseline perfusion profiles on CTP imaging.

Introduction: Current stroke guidelines do not give uniform recommendations regarding the use of CT perfusion (CTP) for the selection of patients presenting within six hours after symptom onset for endovascular treatment (EVT). Model-based analyses can be used to estimate the potential long-term costs and health effects of CTP for patient selection. Methods: In this nationwide retrospective cohort study with model-based health economic evaluation, 703 large vessel occlusion acute ischemic stroke patients with CTP imaging and EVT within six hours after symptom were included (Inclusion: January 2018 - March 2022; trialsearch.who.int:NL7974). CTP-based EVT patient selection using varying ischemic core volumes (ICV) and core-penumbra mismatch ratios (MMR) was compared with providing EVT to all patients. Net monetary benefit (NMB) at a willingness to pay of 80,000 Euro per quality-adjusted life year, the incremental cost-effectiveness ratio (ICER), the difference in costs (dCosts), and quality-adjusted life years (dQALY) per 1000 patients were the outcome measures. Results: The cohort of patients with CTP and EVT used for simulations consisted of 391/703 males with a median age of 72 (IQR:62;81). Considering the most optimal ICV (>110mL) and MMR (<1.4) thresholds, CTP-based selection for EVT resulted in a loss of health (dQALYs: ICV-median:-3.3[IQR:-5.9;-1.1], MMR median:0.0 [IQR:-1.3;0.0]), limited additional costs or cost savings (dCosts: ICV-median:-348,966[IQR:-712,406;-51,158], MMR-median:266,336[IQR:229,403;380,095]), and an ICER and NMB with a wide IQR (ICER ICV-median:71,346[IQR:-16,517;181,241], MMR-median:312,955[IQR:-141,379;infinite]) (NMB ICV-median:102,227[IQR:-282,942;431,923], MMR-median:-278,850[IQR:-457,097:-229,403]). Conclusion: In EVT-eligible patients presenting within six hours after symptom onset, excluding patients based on CTP parameters was not cost-effective and could potentially harm patients.

Background: CT perfusion (CTP) has been suggested to increase the rate of large vessel occlusion (LVO) detection in patients suspected of acute ischemic stroke (AIS) if used in addition to a standard diagnostic imaging regime of CT angiography (CTA) and non-contrast CT (NCCT). The aim of this study was to estimate the costs and health effects of additional CTP for endovascular treatment (EVT)-eligible occlusion detection using model-based analyses. Methods: In this Dutch, nationwide retrospective cohort study with model-based health economic evaluation, data from 701 EVT-treated patients with available CTP results were included (January 2018 - March 2022; trialregister.nl:NL7974). We compared a cohort undergoing NCCT, CTA, and CTP (NCCT+CTA+CTP) with a generated counterfactual where NCCT and CTA (NCCT+CTA) were used for LVO detection. The NCCT+CTA strategy was simulated using diagnostic accuracy values and EVT effects from the literature. A Markov model was used to simulate 10-year follow-up. We adopted a healthcare payer perspective for costs in euros and health gains in quality-adjusted life years (QALYs). The primary outcome was the net monetary benefit (NMB) at a willingness to pay of 80,000 Euro, secondary outcomes were the difference between LVO detection strategies in QALYs (dQALY) and costs (dCosts). Results: We included 701 patients (median age:72 IQR:[62-81]) years). Per LVO patient, CTP-based occlusion detection resulted in cost savings (dCosts median:-2671 IQR:[-4721;-731] Euro), a health gain (dQALY median:0.073 IQR:[0.044;0.104]), and a positive NMB (median:8436 IQR:[5565;11876]) per LVO patient. Conclusion: Adding CTP to NCCT and CTA for EVT-eligible LVO detection resulted in cost savings and health gains.