Risultati per: L'imaging nella urolitiasi

Introduction
Postsurgical hypoparathyroidism (PoSH) is an iatrogenic condition that occurs as a complication of several different procedures with thyroid surgery being the most common. PoSH has significant short- and long-term morbidities. The volume of thyroid surgery is increasing, and PoSH is therefore likely to increase. Some studies have shown promising results using near-infrared fluorescence (NIRF) imaging in reducing the risk of PoSH which has the potential to significantly reduce morbidity and costs associated with monitoring and treatment.

Methods and analysis
NIFTy is an unblinded, parallel group, multicentre, seamless phase II/III randomised controlled trial in patients undergoing total or completion thyroidectomy. The trial incorporates a process evaluation (IDEAL (Idea, Development, Exploration, Assessment and Long-term follow-up framework) 2a) to inform the trial protocol, a phase II (IDEAL 2b) analysis using a surrogate primary outcome of 1 day transient hypocalcaemia to determine early futility and phase III (IDEAL 3) assessment of the primary outcome of PoSH at 6 months after surgery. 454 participants will be randomised on a 1:1 basis to evaluate thyroid surgery with NIRF and indocyanine green against standard thyroid surgery in reducing PoSH at 6 months after surgery, with the phase II analysis occurring once data are available for 200 participants. Analysis in both phases will be using multilevel logistic regression incorporating random effects with respect to surgeon and adjusting for minimisation factors. Phase III secondary outcomes include protracted hypoparathyroidism, hypercalcaemia, complications, length of stay, readmissions and patient reported quality of life using the Short Form 36 Health Survey Questionnaire and Hypoparathyroid Patient Questionnaire instruments.

Ethics and dissemination
NIFTy is funded by National Institute for Health and Care Research Efficacy and Mechanism Evaluation Programme (Grant Ref: 17/11/27) and approved by a Research Ethics Committee (reference: 21/WA/0375) and Health Research Authority (HRA). Trial results will be disseminated through conference presentations, peer-reviewed publication and through relevant patient groups.

Trial registration number
ISRCTN59074092.

Stroke, Volume 56, Issue Suppl_1, Page AWP185-AWP185, February 1, 2025. Introduction:Branch atheromatous disease involving the lenticulostriate artery (LSA) is strongly associated with early neurological deterioration. We aimed to investigate whether an apparent thalamostriate vein (TSV) or brush sign on susceptibility-weighted imaging (SWI) can predict infarct growth.Methods:Consecutive patients with the small subcortical infarction of the LSA presenting within 24 h of onset were retrospectively evaluated. MRI, including SWI, was performed on admission and within 1 week of admission. An apparent TSV was defined as a difference in the diameter of the TSV between the right and left sides on SWI upon admission. Infarct growth was defined as an increase in infarct size on axial or coronal diffusion-weighted imaging from 1 point.Results:Of the 76 patients (median age, 76 [67.25–82] years, 48 male) with the small subcortical infarction of the LSA, 22 (median age, 75.5 [64.75–82.5] years, 13 male) presented with an apparent TSV and/or brush sign. On univariable logistic analysis, only the presence of apparent TSV and/or brush sign (OR, 3.12; 95% CI, 1.11–8.73;p=0.03) was associated with infarct growth. In multivariable logistic regression analysis, age (OR, 1.07; 95% CI, 1.01–1.14;p=0.02) and infarct growth (OR, 4.46; 95% CI, 1.37–14.54;p=0.01) were independently associated with progressive paralysis.Conclusion:An apparent TSV or brush sign could indicate infarct growth in cases of the small subcortical infarction of the LSA.

Stroke, Volume 56, Issue Suppl_1, Page AWP181-AWP181, February 1, 2025. Background:Timely intervention is crucial for patients with acute ischemic stroke. The RapidAI imaging system (RAPID) was implemented to enhance the speed and efficiency of care delivery. We evaluated the impact of RAPID on various metrics in the patient care pathway.Methods:In this retrospective observational study, we analyzed consecutive patients who presented to our hospital ER with acute ischemic stroke and who were treated with Intravenous Thrombolysis (IVT) or mechanical thrombectomy between December 20, 2014, and April 20, 2024. Patients were divided into pre-RAPID (n =186) and post-RAPID (n =264) groups based on the implementation date of the RAPID system (September 1, 2019). We compared Door to Non-contrast CT (NCCT), Door to CT Angiography (CTA) / Perfusion Imaging, Door to IVT, and Door to Puncture / first pass for thrombectomy, between the two groups using Fisher’s exact test.Results:For Door to CT, no significant difference was observed between pre-RAPID and post-RAPID groups; 74% of patients in the post-RAPID group and 71% in the pre-RAPID group received NCCT within 45 minutes (p= 0.44). Significant improvements were observed in Door to CTA/Perfusion times; 90% of patients received vessel or perfusion imaging within 150 minutes post-RAPID compared to 70% pre-RAPID (p= 0.01), and 87% received imaging within 120 minutes post-RAPID compared to 70% pre-RAPID (p= 0.031). For Door to IVT, 96% of patients received treatment within 120 minutes post-RAPID compared to 82% pre-RAPID (p= 0.015). For thrombectomy, there was a trend toward faster door to puncture post-RAPID; 70% of patients were treated within 150 minutes post-RAPID compared to 62% pre-RAPID (p= 0.36), and 90% were treated within 210 minutes post-RAPID compared to 81% pre-RAPID (p= 0.12). Similarly, a trend toward faster Door to First Pass times was observed post-RAPID, with 88% treated within 240 minutes compared to 80% pre-RAPID (p= 0.20).Conclusions:RapidAI Implementation was associated with significant improvements in key workflow metrics, notably in Door to Vessel/Perfusion Imaging and Door to IVT. These findings suggest that RAPID enhances the efficiency of patient care delivery in acute ischemic stroke. Further studies with larger sample sizes are warranted.

Stroke, Volume 56, Issue Suppl_1, Page AWP184-AWP184, February 1, 2025. Objective:High calcium (Ca), low phosphate(P), and Ca-P product (CPP) levels are associated with cardiovascular disease and coronary artery atherosclerosis in patients with chronic kidney disease. However, whether this relationship persists in individuals with carotid artery atherosclerosis of acute ischemic stroke is unknown. We investigated the association of serum Ca, P, and CPP to carotid artery atherosclerotic plaque assessed by high-resolution MR vessel wall imaging in acute ischemic stroke patients.Methods:A total of 251 ischemic stroke participants with carotid artery atherosclerosis (mean age 68 years old, male 80.1%) were consecutively included in a comprehensive stroke center. Serum Ca, and P were obtained from blood tests after admission, and carotid artery plaque characteristics including plaque burden and vulnerability were evaluated using high-resolution MR vessel wall imaging, then the association between serum Ca, P, CPP, and atherosclerosis plaque characteristics was analyzed in multi-variate linear or logistic regression analysis； Finally, the consistency was also explored in different subgroups.Results:The mean±SD of serum Ca and P in this population is 2.26±0.11 and 1.16±0.19 individually. Serum P and CPP were associated with carotid artery plaque burden, presented as maximum wall thickness (max WT), wall area, and lipid-rich necrotic core (LRNC), in univariate analysis, with β=-0.205，95% CI (-0.348,-0.061), β=-0.258，95% CI (-0.405,-0.113), OR=0.182, 95% CI (0.034,0.975) for P, and β=-0.203，95% (-0.346,-0.059), β=-0.221，95% CI (-0.366,-0.074), OR=0.466, 95% CI (0.237,0.915) for CPP, respectively. In multivariate regression analysis, after further correction of age, sex in model 1 and cardiovascular risk factors in model 2, P level is associated with wall area independently, β=-0.211, 95% CI (-0.367, -0.052), while CPP is associated with wall area marginally, with β=-0.147, 95%CI (-0.300, 0.008) in model 1, and β=-0.157, 95%(-0.314, 0.004) in model 2. In subgroup analysis, the independent relationship between P and wall area can still be consistent in age＞65 years (β=-0.222, 95%CI [-0.400, -0.011]), male (β=-0.219， 95%CI [-0.446,-0.045], and hypertension (β=-0.314， 95%CI [-0.513, -0.130] subgroups.Conclusion:Lower serum P was associated with increased carotid artery plaque burden presented with wall area, and this relationship could differ in different age, sex, and hypertension subgroups.

Stroke, Volume 56, Issue Suppl_1, Page AWP195-AWP195, February 1, 2025. Introduction:Randomized clinical trials evaluating the effects of endovascular treatment (EVT) for medium vessel occlusion (MeVO) are ongoing. However, it remains unclear how clinicians determine the indication for EVT in MeVO cases in real-world practiceHypothesis:We hypothesize that in actual clinical practice, there is a threshold of clinical symptoms and perfusion imaging findings that guide the decision to intervene with EVT for MeVO.Methods:We conducted a single-center retrospective registry from April 2019 to April 2024, enrolling consecutive patients with acute ischemic stroke due to MeVO. We compared the outcomes of MeVO patients who received EVT with those who received medical treatment (MT). The primary outcome was defined as a good functional outcome, indicated by a modified Rankin scale score of 0-2 at 90 days post-stroke onset. Secondary outcomes included exploring the optimal thresholds for EVT intervention in real-world clinical practice, based on clinical symptoms indicated by the National Institutes of Health Stroke Scale and perfusion imaging using RAPID software.Results:We analyzed 162 patients (EVT, n = 102; MT, n = 60). The mean age was 80 years, with 53.7% being men. Recombinant tissue plasminogen activator was used more frequently in the EVT group (42.2% vs. 18.3%). The median NIHSS was higher in the EVT group (median [interquartile range, IQR]; 13 [6–19] vs. 7 [2–14]). In terms of perfusion imaging, there was no significant difference between the two groups in CBF < 30% (median [IQR]; 4 [0–17] vs. 4 [0–22]). However, the median T max > 6 sec and mismatch volume were significantly higher in the EVT group (median [IQR]; 44 [27–82] vs. 28 [6–49] and 35 [21–55] vs. 12 [2–28], respectively). The primary outcome was not significantly different between the EVT and MT groups (41 [40.2%] vs. 25 [41.7%]; adjusted odds ratio [aOR]: 1.10 [95% CI: 0.42–2.89]). Receiver-operating characteristic analyses showed that the areas under the curves for NIHSS, CBF < 30%, T max > 6 sec, and mismatch volume were 0.64, 0.49, 0.68, and 0.74, respectively. Mismatch volume had the best discriminatory power with respect to EVT intervention, with a threshold of 20 ml.Conclusions:A mismatch volume of ≥ 20 ml may be a useful criterion for determining EVT intervention in MeVO cases in real-world practice.

Stroke, Volume 56, Issue Suppl_1, Page ATMP11-ATMP11, February 1, 2025. Introduction:Moyamoya disease (MMD) is a rare cerebrovascular disease causing nonatherosclerotic intracranial arterial stenosis in children and young adults. TheRNF213gene variant plays an important role in the pathophysiology of MMD, particularly among East Asian populations. However, this variant is rarely found in patients of other ethnicity. Previous studies have shown thatRNF213gene variant is related to vascular structures such as the extent of moyamoya collaterals and posterior cerebral artery involvement. In this study, we utilize an imaging-based approach to investigate vascular structural features in MMD, which may offer novel insights into the pathophysiology of MMD.Methods:We retrospectively reviewed 770 patients with MMD or Moyamoya syndrome (MMS) from diverse ethnic backgrounds at Stanford University Medical Center treated between 2015 and 2024 (Fig. 1). After selecting sporadic non-hemorrhagic bilateral MMD patients aged 18-50 years old, the vascular structures acquired on MRA were visually assessed to evaluate the degree of intracranial arterial stenosis and basal moyamoya collaterals. T2 weighted images were reviewed to assess negative remodeling – shrinkage of the outer diameter of middle cerebral arteries (MCA) and internal cerebral arteries (ICA) as defined by Kuroda et al.2015, Neurol Med Chir (Tokyo).Results:Detailed demographic and clinical characteristics of 107 patients evaluated were listed in Table 1. By reviewing MRA, we have identified a subset of patients with unique imaging features characterized by ICA stenosis localized proximal to the terminal portion of ICA, differing from the typical lesion sites seen in MMD (Fig. 2). This non-terminal ICA stenosis was more frequently observed in Caucasian than in Asian patients (17.5% vs. 5.7%, P=0.007). Compared to patients with terminal ICA and/or MCA stenosis, patients with non-terminal ICA stenosis were older (P=0.03), had less advanced disease stages (P

Stroke, Volume 56, Issue Suppl_1, Page ATP303-ATP303, February 1, 2025. Background:Prior studies indicate a relationship between migraine and MACE. Here we assess whether brain white matter hyperintensities (WMH), which are a common imaging finding in patient with migraine, contribute to the risk of MACE above demographics and common risk factors for MACE.Methods:60,454 patients, ages 18-89, with a ICD-9 or ICD-10 migraine diagnosis code in 2010 or later were identified from the Mayo Clinic electronic health record. Only patients who were seen for migraine in the Neurology Department were included. Patients with a migraine diagnosis who did not have MACE were included only if they had at least two visits at Mayo Clinic during five years. Only patients with sex and race information were included. The final cohort included 577 migraine patients with and 598 migraine patients without MACE. Presence of WMH was determined from radiology notes. Individuals without a brain MRI were assumed not to have WMH. A logistic regression model that included sex, race, known lifetime MACE risk factors (atrial fibrillation, diabetes, hypertension, hyperlipidemia, tobacco use) and WMH as independent variables to predict MACE outcome was fit.Results:Significant factors that increased the risk of MACE in individuals with migraine included being Black or African American (adjusted OR: 2.9, 95% CI: 1.24-6.82, p = 0.014), presence of atrial fibrillation (adj. OR: 1.63, 95% CI: 1.23-2.17, p < 0.001), diabetes (adj. OR: 1.34, 95% CI: 1.02-1.75, p = 0.036), hypertension (adj. OR: 1.9, 95% CI: 1.39-2.6, p < 0.001), tobacco use (adj. OR: 1.66, 95% CI: 1.29-2.14, p < 0.001), and the presence of WMH (adj. OR: 1.43, 95% CI: 1.1-1.87, p = 0.008). Hyperlipidemia showed a marginal association (adj. OR: 1.34, 95% CI: 0.99-1.81, p = 0.061), while other variables such as sex and other racial/ethnic groups did not significantly alter the risk of MACE outcome.Discussion:Results indicate that African American race and presence of WMH in addition to common comorbidities independently increase the risk of MACE outcome.

Stroke, Volume 56, Issue Suppl_1, Page AWP177-AWP177, February 1, 2025. Introduction:Automated imaging analysis tools are increasingly used in clinical decision-making for stroke. Rapid ASPECTS (iSchemaView, Menlo Park, CA) assists physicians by automatically calculating Alberta Stroke Program Early CT Scores (ASPECTS) and reducing inter-reader variability. To understand why the tool’s performance in real-world settings sometimes varies compared to published literature, we investigated how different imaging acquisition protocols affect its performance.Materials&Methods:Consecutive code stroke NCCT scans with thin (1.25 mm slice; 0.625 mm spacing) and thick (5.0 mm slice; 3 mm spacing) series were collected from a retrospective database between February 2020 and May 2021. Ground truth ASPECTS reads were collected from radiology reports, which neuroradiologists determined in real-time. Automated reads were obtained using Rapid ASPECTS 1.0 and 3.0 (iSchemaView, Menlo Park, CA). Agreement between automated and manual reads was defined as ASPECTS scores within two points.Results:A total of 682 cases were included in this analysis. 67 cases were excluded for technical inadequacy (hemorrhages, tumors, and artifacts). A review of the source imaging revealed that many cases had thick overlapping slices and incorrect head positioning (neck extended instead of the standard neutral position). These cases required significant tilt correction to align the patient data with the Rapid ASPECTS regions template. These corrections led to partial voluming artifacts, which caused lower Hounsfield unit (HU) values and ASPECTS scores. When adjusting protocols from thick to thin slices, agreement between ASPECTS V1 and manual reads improved from 85% (581/682) to 89% (606/682). ASPECTS V3 showed further improvement, with agreements of 91% (619/682) and 95% (648/682) for thick and thin slice scans, respectively.Conclusion:The combination of neck extension head positioning and thick overlapping slices caused partial voluming artifacts, resulting in artificially low ASPECTS scores on automated software. Our findings indicate that adjusting imaging protocols and working with the AI provider can enhance an algorithm’s accuracy. To ensure that commercially available automated analysis tools deliver accurate results, it is crucial to follow the recommended imaging acquisition protocols.

Stroke, Volume 56, Issue Suppl_1, Page ATMP59-ATMP59, February 1, 2025. Introduction:Diffusion-weighted imaging (DWI) is key for detecting acute ischemic brain lesions but struggles with hyperacute or small lesions that mimic artifacts. This randomized crossover trial assessed whether an artificial intelligence (AI) solution enhances diagnostic accuracy for these challenging lesions compared to conventional interpretation.Methods:From February 2017 to November 2021, 4,071 suspected acute ischemic stroke patients underwent initial and follow-up DWI. A neurologist assessed ischemic stroke based on medical records, and a neuroradiologist established the ground truth using the neurologist’s evaluation, MRI reports, and AI-marked DWI images. The accuracy of AI and MRI reports was then evaluated against this ground truth.For a reader performance study, 874 challenging cases were selected: (1) infarct volume < 0.5 mL in the posterior circulation on follow-up DWI or (2) initial DWI within 3 hours of onset with infarct volume < 1.0 mL in the anterior circulation. Additionally, 80 negative and 40 positive control cases were included. Five readers (a neuroradiologist, two radiology residents, and two neurology residents) interpreted the DWIs, half with AI assistance and half without. After a 4-week washout, cases were re-evaluated with the groups reversed. We compared the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and Dice similarity coefficient (DSC) between readings with and without AI.Results:Of 3,981 patients, 3,465 had acute ischemic strokes, and 516 had MRI-negative transient ischemic attacks. The AI alone showed a positive predictive value (PPV) of 93.1% and a negative predictive value (NPV) of 81.3%. The PPV of AI varied significantly with predicted infarction volume: 81.7% for ≤ 0.5 mL vs. 99.5% for > 0.5 mL. With AI, the sensitivity of MRI reports could potentially increase from 98.5% to 99.7%, ensuring identification of all false negatives.In the challenging case reader study, AI significantly increased AUC (0.848 vs. 0.927; p < 0.001) and sensitivity (74.59% to 90.59%; p < 0.001), with minimal impact on specificity (88.75% vs. 84.00%; p = 0.0496). AI-assisted segmentation also showed higher DSC compared to non-AI segmentation (0.742 vs. 0.523; p < 0.001).Conclusions:AI significantly improved the diagnostic performance for challenging acute ischemic lesions on DWI, demonstrating the potential to enhance stroke care.

Stroke, Volume 56, Issue Suppl_1, Page A35-A35, February 1, 2025. Introduction:AI imaging decision support software is recommended by UK and USA stroke guidelines to facilitate identification and transfer of stroke patients eligible for endovascular therapy (EVT) but the impact on thrombectomy delivery is unclear. This prospective observational study evaluated the impact of Brainomix 360 Stroke software in four stroke networks (28 hospitals) in England’s National Health Service (NHS). The primary outcome was percentage of acute stroke patients receiving EVT (the EVT rate); door-in door-out (DIDO) times were assessed as a secondary outcome.Methods:Data were collected prospectively from the Sentinel Stroke National Audit Programme. The impact of Brainomix 360 Stroke software was assessed in two ways: comparison of EVT rates at the 28 evaluation sites and non-evaluation NHS sites before and after implementation (pre-implementation: Jan 2019-Feb 2020; post- : Jan 2022-Feb 2023); comparison of EVT rates and DIDO times at evaluation sites after implementation in patients for whom AI software was used and in those it was not. Multivariate regressions were used to evaluate whether AI use was a predictor of EVT or DIDO time, accounting for other clinical variables (e.g., age, NIHSS, day of week, time of day, time since onset).Results:The dataset included 71,327 patients from 28 evaluation hospitals. Figure 1 shows the change in EVT rates over time in evaluation (blue) and non-evaluation sites (yellow). EVT rate at evaluation sites increased from 2.3% pre-implementation to 4.6% post-implementation (p

Stroke, Volume 56, Issue Suppl_1, Page ATP160-ATP160, February 1, 2025. Background and Purpose:Deep tiny flow voids (DTFVs) are a specific type of collaterals surrounding chronic steno-occlusive middle cerebral artery (MCA), which can be identified on high-resolution magnetic resonance imaging (HR-MRI). This study aimed to investigate the presence of DTFVs in patients with acute MCA occlusion and their relevance to clinical outcomes.Methods:Using data from two multicenter cohort studies, we examined the presence of DTFVs in patients with acute MCA occlusion and analyzed their clinical and imaging characteristics. Univariable and multivariable logistic and linear regression analyses were conducted to assess the correlation between DTFVs and the 90-day modified Rankin Scale (mRS) scores. We further studied the mediating effect of residual flow distal to MCA occlusion on the relationship between DTFVs and 90-day mRS scores using mediation analysis.Results:One hundred and twenty-three patients with acute MCA occlusion were included. The median age was 61 years (interquartile range [IQR], 51-67 years), and 73.73% of the patients were male. The median time from symptom onset to imaging was 44 hours (IQR, 25-67 hours). Sixty-six patients (53.66%) exhibited DTFVs on HR-MRI. Lower baseline NIHSS scores (4.5 [2-8] vs. 10 [4-14]) and smaller infarct volumes (5.76 [2.79-15.34] cm3vs. 19.01 [7.16-83.59] cm3) were observed in patients with DTFVs compared to those without. Both multivariable logistic regression (odds ratio [OR]: 6.22, 95% confidence interval [CI]: 1.82 to 21.29, p = 0.004) and linear regression analysis (β: -0.60, 95% CI: -1.06 to -0.14, p = 0.012) indicated that patients with DTFVs exhibited better 90-day functional outcomes. The mediating effect analysis showed that the effect of DTFV on 90-day mRS scores was partially mediated by residual flow distal to MCA occlusion, with a proportion of 30.66% (95% CI: 8.97 to 69.29, p = 0.002).Conclusions:In our study population, the presence of DTFVs was associated with a favorable outcome in patients with acute MCA occlusion, which may exert a protective effect partly by contributing to the formation of distal residual flow at the occlusion sites. Future studies are needed to investigate the potential of DTFVs in guiding individualized treatment strategies.

Stroke, Volume 56, Issue Suppl_1, Page AWP95-AWP95, February 1, 2025. Introduction:The choice of initial imaging modality significantly impacts door-to-puncture time (DPT) in acute ischemic stroke (AIS) patients undergoing endovascular thrombectomy (EVT). Studies have shown that using CT as the first imaging modality can reduce DPT compared to MRI. In July 2023, we revised critical pathway (CP) protocols including first image modalities from MRI to CT regardless of last known normal time (LNT). Therefore, we evaluated the impact of process modification including first image modalities could reduce the DPT for the EVT candidates.Methods:Prior to July 2023, EVT candidate AIS patients who visited Seoul National University Bundang Hospital, comprehensive stroke center, received CT as the first imaging modality if they arrived within 6 hours after onset, while others underwent MRI. From July 2023, all patients with disabling symptoms or an NIHSS score of 6 or higher received CT as the initial imaging, irrespective of LNT. We retrospectively analyzed the single center quality indicators, including DPT, door-to-image time, door-to-reperfusion time, and proportion of symptomatic intracerebral hemorrhage (sICH) comparing outcomes before and after the protocol change.Results:The total number of AIS patients undergoing EVT increased from 396 in the first half of 2022 to 442 in the second half of 2023. Median DPT decreased from 71 minutes in early 2022 to 60 minutes after the protocol change, with a corresponding increase in the proportion of patients achieving DPT within 60 minutes from 37.5% to 52.2%. The median door-to-image time for patients receiving CT decreased from 27 minutes to 22.5 minutes, with 94% achieving imaging within 30 minutes post-change compared to 70% pre-change. MRI, on the other hand, showed a median door-to-image time reduction from 30 minutes to 28.5 minutes, but only 50% achieved imaging within 30 minutes. Overall, the median door-to-reperfusion time decreased from 130 minutes to 105 minutes, with the proportion of patients achieving reperfusion within 120 minutes increasing from 37.9% to 62.5%. There was no significant change in proportion of sICH.Conclusions:The protocol change to a CT-first approach significantly improved key EVT quality indicators, particularly in reducing door-to-puncture time. These findings underscore the importance of optimizing imaging strategies to enhance outcomes in AIS patients undergoing EVT.

Stroke, Volume 56, Issue Suppl_1, Page ATP165-ATP165, February 1, 2025. Background:Posterior circulation (PC) large-vessel occlusion (LVO) strokes have significant morbidity and mortality, but patient selection for acute interventions remains understudied. Multiple computed tomography (CT)-based scores exist, including the CT-perfusion-based CAPS score, CT-angiogram(CTA)-based BATMAN and PC-CTA scores, and CTA source image or non-contrast-CT-based PC-ASPECTS score, but their predictive values for long-term outcomes after thrombectomy have not been directly compared.Methods:We conducted a retrospective multicenter cohort study of patients with basilar artery occlusions treated with endovascular thrombectomy. Four CT-based scores were assessed: PC-ASPECTS, BATMAN, PC-CTA, and CAPS. The primary outcome of interest for the study was favourable functional outcome at 3 months (mRS of 0-3). We generated receiver operating characteristic curves measuring area under the curve (AUC) for poor functional outcomes and compared AUCs with non-parametric methods.Results:98 patients were included for analysis, with an average age of 64.9±15.6 years.The median National Institute of Health Stroke Severity Score (NIHSS) was 13.5 (IQR 7.0 – 23.0). AUC values were highest for the CAPS score (AUC 0.72 (95%CI 0.63 – 82)), and lowest for the pc-CTA score (AUC 0.57 (95%CI 0.45 – 0.68)), p=0.019. There was a trend towards the CAPS score outperforming the BATMAN (AUC 0.66 (95%CI 0.55 – 0.77) and PC-ASPECTS scores (AUC 0.63 (95%CI 0.52 – 0.75)), though this difference was not statistically significant (p=0.29 and p=0.23, respectively). However, the CAPS score was the only score with 100% specificity for predicting inability to achieve good functional outcome after thrombectomy: 0/12 patients with CAPS score of 4-6 went on to have a good functional outcome at 3 months after thrombectomy.Conclusion:Our analysis demonstrated that the CT-perfusion-based CAPS score outperformed three other imaging-based scores for predicting outcomes after 3 months. The CAPS score could be implemented to inform patient selection for endovascular thrombectomy in basilar artery occlusions.

Stroke, Volume 56, Issue Suppl_1, Page A33-A33, February 1, 2025. Introduction:Net water uptake (NWU) is a novel biomarker which measures edema and tissue injury from the degree of hypoattenuation on non-contrast CT and may serve as a precision tool for predicting outcomes after acute ischemic stroke (AIS). Using our recently developed algorithm, this study aimed to evaluate the relationship between NWU and post-stroke neurologic outcomes, including language impairment and motor weakness.Methods:Consecutive patients treated for AIS at certified stroke centers in Houston, TX were included. Patients’ precise functional outcomes at hospital discharge were recorded including decreased level of consciousness, presence of language impairment, visual deficit, arm and leg weakness, need for walking assistance, and gastrostomy placement. The primary outcome for this study was the performance of calculated NWU and clinical variables to predict language impairment at discharge. Baseline characteristics were compared, and then univariate and multivariate logistic regression were used to evaluate the association between clinical variables, imaging data, and the precise neurological outcomes.Results:Among 776 patients with AIS, average age was 67.0 +/- 14.8, 47.8% were female, median NIHSS was 10 [5,18], median ASPECTS was 9 [7,10], 42.6% received tPA, and 67.1% had a large vessel occlusion (see Table 1). In univariate logistic regression, higher NWU (OR 1.45, CI 1.30-1.63) and lower ASPECTS (OR 0.68, CI 0.63-0.74) were both significantly associated with higher likelihood of language impairment and other deficits at discharge (see Table 2). Additionally, higher NWU in all ten regions was significantly associated with deficit at discharge. In multivariate logistic regression, certain clinical and imaging variables remained significantly associated as described in Table 3. The ASPECTS and NWU-based regression models were directly compared when predicting language impairment using ROC curve analysis, and areas under the curve were 0.838 vs. 0.851 respectively (p = 0.152 with Delong test, see Figure 1).Conclusion:The novel NWU biomarker was significantly associated with precise post-AIS outcomes at discharge. When controlling for confounders, NWU was non-inferior to ASPECTS. Moving forward, region-based and overall NWU will need to be studied with long-term patient outcomes. Ultimately, this novel and open-access imaging biomarker could be used in the emergency setting to guide treatment decision-making and patient counseling.

Stroke, Volume 56, Issue Suppl_1, Page ATP164-ATP164, February 1, 2025. Background:Ischemic stroke is a leading causes of death and disability and imaging is essential when determining treatment. Currently, both computed tomography (CT) and magnetic resonance (MR) are accepted as options for first imaging of stroke. Whether MR or CT is more advantageous for first stroke imaging has yet to be determined in a randomized study. The goal of this study was to determine feasibility of randomizing code stroke patients to MR or CT.Methods:Multisite, randomized, prospective study of code stroke patients presenting within a 12-week window to 4 certified stroke centers. Hospital-level cluster randomization assigned each site 6 CT-first weeks, and 6 MR-first weeks. Patients ≥18 years presenting with stroke symptoms < 24 hours with active code strokes at time of first imaging were included. Patients transferred from another hospital or who received prior imaging at an outside facility were excluded. Demographics, clinical stroke variables, and workflow metrics were extracted from the local stroke database or patient electronic health records. A univariate logistic regression model was used to evaluate the primary outcome: compliance (i.e. proportion of patients scanned according to assigned imaging). We hypothesized compliance would be comparable to that seen when MR-first was the preferred standard of care, ≥60%, demonstrating feasibility.Results:406 patients (199 females; mean age 67 years, range 24 - 103) were included in the analysis (Table 1). Compliance with assignment to CT was 90%, compliance with MR was 66%. Those assigned to MR were significantly less likely to be scanned as assigned (OR: 0.21, 95% CI [0.12-0.36]). Reasons for non-compliance included both process-related (e.g. MR scanner in use) and patient-related reasons (e.g. medically unstable). Most frequently, the reason for non-compliance was not documented.Conclusion:This study is the first step in evaluating feasibility for a large-scale randomized clinical trial to determine whether MR or CT is preferable as the first stroke imaging modality. Compliance with assignment (MR or CT) our preset threshold of 60%, with significantly higher compliance when CT was assigned compared to MR. With mitigation of process-related barriers to randomization compliance, these results inform next steps in optimizing a future trial.

Stroke, Volume 56, Issue Suppl_1, Page A74-A74, February 1, 2025. Introduction:Endovascular thrombectomy (EVT) dramatically improves clinical outcomes, but the reduction in final infarct volume only accounts for a minority of the treatment effect. There is a need for surrogate imaging biomarkers that more strongly associate with functional outcome, to refine prognostication and facilitate development of EVT-adjuvant neuroprotective therapies. Our group recently developed a straightforward ADC-based metric of post-EVTinfarct density(i.e. a measure of infarct severity). We aimed to validate this novel metric in a multicenter study of EVT patients.Methods:A retrospective cohort included consecutive patients with anterior circulation LVO who underwent EVT at two stroke centers. MRI was performed 12–48 hours post-EVT. Good functional outcome was defined as a 90-day modified Rankin Scale score ≤2. MR imaging was processed via RAPID, and final infarct volume was based on the standard ADC