scholarly journals Real-World Comparison of Human and Software Image Assessment in Acute Ischemic Stroke Patients’ Qualification for Reperfusion Treatment

2020 ◽  
Vol 9 (11) ◽  
pp. 3383
Author(s):  
Bartlomiej Lasocha ◽  
Roman Pulyk ◽  
Pawel Brzegowy ◽  
Pawel Latacz ◽  
Agnieszka Slowik ◽  
...  
Keyword(s):  
Real World ◽  
Ct Perfusion ◽  
Reperfusion Therapy ◽  
Computer Algorithms ◽  
Stroke Patients ◽  
Volume Measurements ◽  
Manual Methods ◽  
Rapid Processing ◽  
Image Assessment

Our aim was to compare human and computer accuracy in reading medical images of acute stroke patients. We analyzed data of patients who underwent assessment of Alberta Stroke Program Early CT Score (ASPECTS) and CT Perfusion (CTP) via Rapid Processing of Perfusion and Diffusion (RAPID) software RAPID ASPECTS, and RAPID CTP), compared to radiologist reports and manual measurements. We compared volumes calculated by RAPID CTP software with those selected by scanner-equipped software (GE). For reference, follow-up images were manually assessed in accordance with the Alberta Stroke Program Early CT Score (ASPECTS) territories retrospectively. Although exact ASPECTS score agreement between the automatic and manual methods, and between each method and follow-up, was poor, crossing of the threshold for reperfusion therapy was characterized by an 80% match. CT perfusion analyses yielded only slight agreement (kappa = 0.193) in the qualification of patients for therapy. Either automatic or manual scoring methods of non-contrast images imply similar clinical decisions in real-world circumstances. However, volume measurements performed by fully automatic and manually assisted systems are not comparable. Thresholds devised and validated for computer algorithms are not compatible with measurements performed manually using other software and should not be applied to setups other than those with which they were developed.

Incorporation of relative cerebral blood flow into CT perfusion maps reduces false ’at risk' penumbra

2017 ◽  
Vol 10 (7) ◽  
pp. 657-662 ◽  
Author(s):  
Shlomi Peretz ◽  
David Orion ◽  
David Last ◽  
Yael Mardor ◽  
Yotam Kimmel ◽  
...  
Keyword(s):  
At Risk ◽  
Acute Stroke ◽  
Ct Perfusion ◽  
False Negative ◽  
Stroke Patients ◽  
True Negative ◽  
True Negative Rate ◽  
Negative Rate ◽  
Perfusion Maps

PurposeThe region defined as ‘at risk’ penumbra by current CT perfusion (CTP) maps is largely overestimated. We aimed to quantitate the portion of true ‘at risk’ tissue within CTP penumbra and to determine the parameter and threshold that would optimally distinguish it from false ‘at risk’ tissue, that is, benign oligaemia.MethodsAmong acute stroke patients evaluated by multimodal CT (NCCT/CTA/CTP) we identified those that had not undergone endovascular/thrombolytic treatment and had follow-up NCCT. Maps of absolute and relative CBF, CBV, MTT, TTP and Tmax as well as summary maps depicting infarcted and penumbral regions were generated using the Intellispace Portal (Philips Healthcare, Best, Netherlands). Follow-up CT was automatically co-registered to the CTP scan and the final infarct region was manually outlined. Perfusion parameters were systematically analysed – the parameter that resulted in the highest true-negative-rate (ie, proportion of benign oligaemia correctly identified) at a fixed, clinically relevant false-negative-rate (ie, proportion of ‘missed’ infarct) of 15%, was chosen as optimal. It was then re-applied to the CTP data to produce corrected perfusion maps.ResultsForty seven acute stroke patients met selection criteria. Average portion of infarcted tissue within CTP penumbra was 15%±2.2%. Relative CBF at a threshold of 0.65 yielded the highest average true-negative-rate (48%), enabling reduction of the false ‘at risk’ penumbral region by ~half.ConclusionsApplying a relative CBF threshold on relative MTT-based CTP maps can significantly reduce false ‘at risk’ penumbra. This step may help to avoid unnecessary endovascular interventions.

Abstract WMP15: A Simple Tool to Predict Target Mismatch in Ischemic Stroke Patients with Anterior Circulation Occlusion

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Adam de Havenon ◽  
Steve O’Donnell ◽  
Alex Linn ◽  
Scott McNally ◽  
Bailey Dunleavy ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Perfusion Imaging ◽  
Time Window ◽  
Ct Perfusion ◽  
Volumetric Analysis ◽  
Stroke Patients ◽  
Anterior Circulation ◽  
Ct Angiogram

Introduction: The efficacy of endovascular thrombectomy in an extended time window for acute ischemic stroke patients with Target Mismatch (TM) on perfusion imaging was shown in a recent study and the ongoing DEFUSE-3 trial is studying thrombectomy in a 6-16 hour window for TM patients. A limitation of TM is that perfusion imaging is not widely available. We sought to identify a tool to predict TM based on clinical factors and CT angiogram (CTA) imaging, which is available at most hospitals. Methods: We reviewed acute ischemic stroke patients from 2010-2014 with proximal middle cerebral artery occlusion, CTA and CT perfusion (CTP) at hospital admission. TM was identified on CTP using the Olea Sphere volumetric analysis software with Bayesian deconvolution. TM was defined by the DEFUSE-3 criteria. ASPECTS was derived from the non-contrast CT head and the CTA source images (CTA-ASPECTS). Two collateral scores were derived from CTA source images. Results: 61 patients met inclusion criteria. The mean±SD age was 61±18 years and 61% were male. Mean NIH Stroke Scale (NIHSS) was 14.1±8.0 and median (IQR) follow-up modified Rankin Scale was 3 (1,6). TM was present in 35/61 (57%), who had lower mRS at follow-up (z=3.5, p<0.001). The predictor variables are shown in Table 1. The best combination of predictors was CTA-ASPECTS >4 and NIHSS <16, which had a sensitivity of 80% and specificity of 85% for TM (Figure 1). Discussion: We report a reliable, accessible, and clinically useful tool for predicting TM. This score warrants further study as a tool to guide transfer decisions from primary or secondary stroke centers to tertiary centers where endovascular intervention would be possible for selected patients.

Abstract TP41: Perfusion CT Identifies Ischemic Stroke Patients With a Good Natural History Regardless of Treatment

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Andrew Bivard ◽  
Venkatesh Krishnamurthy ◽  
christopher Levi ◽  
Mark Parsons
Keyword(s):  
Ischemic Stroke ◽  
Natural History ◽  
Ct Perfusion ◽  
Reperfusion Therapy ◽  
Minor Stroke ◽  
Small Lesion ◽  
Stroke Patients ◽  
Primary Analysis ◽  
Eligibility Criteria ◽  
Vessel Occlusion

Introduction: There remains uncertainty about the benefits of reperfusion therapy in minor stroke. In this study we tested the hypothesis that patients with a small perfusion lesions do not show clinical benefit from reperfusion therapy when using conventional outcome scores such as the modified Rankin scale. Methods: A prospective cohort of consecutive ischemic stroke patients who fulfilled standard clinical/NCCT eligibility criteria with additional perfusion and angiography CT before treatment with iv alteplase were collected. Volumetric CT perfusion was retrospectively analysed to identify patients with a small perfusion lesion (defined as a delay time lesion 3 seconds <15mL). The primary analysis compared 3-month mRS as well as acute and 24 hour NIHSS scores in patients with a small perfusion lesion who were treated with rtPA against those who were not using linear regression to generate and odds ratios (OR). Results: Of the 1526 patients who were potentially eligible for alteplase therapy, 356 had a perfusion lesion <15mL with 211 being treated and 145 not treated with rtPA. Patients with a small perfusion lesion had similar NIHSS between those who were treated and those not treated (rtPA treated small lesion patients acute NIHSS, 8.2, untreated 8.9, p=0.71). The odds of small lesion patients achieving mRS 0-1 with alteplase was 0.614 (p<0.001). Average 24 hour DWI lesion in treated small perfusion lesion patients 3mL with alteplase treatment and 2.1mL without, p=0.081. The subgroup of patients with a small perfusion lesion associated with a vessel occlusion did however show an improvement in functional outcome (mRS 0-1OR 1.21, p=0.012). Conclusion: Ischemic stroke patients with a small perfusion lesion appear to have an excellent natural history regardless of alteplase treatment. Patients with a visible vessel occlusion may have a slight benefit from treatment.

Abstract WMP11: Interhospital Transfer versus Direct Admission of Acute Stroke Patients Undergoing Endovascular Reperfusion Therapy: A Real-World Experience in Japan

Stroke ◽  
2019 ◽  
Vol 50 (Suppl_1) ◽  
Author(s):  
Mikito Hayakawa ◽  
Masayuki Sato ◽  
Masataka Yoshimura ◽  
Arihito Tsurumi ◽  
Takuya Kawai ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Real World ◽  
Reperfusion Therapy ◽  
Stroke Patients ◽  
Interhospital Transfer ◽  
Direct Admission

scholarly journals Relationship between the degree of recanalization and functional outcome in acute ischemic stroke is mediated by penumbra salvage volume

2021 ◽  
Author(s):  
Gabriel Broocks ◽  
Hashim Jafarov ◽  
Rosalie McDonough ◽  
Friederike Austein ◽  
Lukas Meyer ◽  
...  
Keyword(s):  
Functional Outcome ◽  
Ct Perfusion ◽  
Reperfusion Therapy ◽  
Anterior Circulation ◽  
Vessel Occlusion ◽  
Important Mediator ◽  
Flow Restoration ◽  
Relationship Of ◽  
The Relationship

Abstract Background The presence of metabolically viable brain tissue that may be salvageable with rapid cerebral blood flow restoration is the fundament rationale for reperfusion therapy in patients with large vessel occlusion stroke. The effect of endovascular treatment (EVT) on functional outcome largely depends on the degree of recanalization. However, the relationship of recanalization degree and penumbra salvage has not yet been investigated. We hypothesized that penumbra salvage volume mediates the effect of thrombectomy on functional outcome. Methods 99 acute anterior circulation stroke patients who received multimodal CT and underwent thrombectomy with resulting partial to complete reperfusion (modified thrombolysis in cerebral infarction scale (mTICI) ≥ 2a) were retrospectively analyzed. Penumbra volume was quantified on CT perfusion and penumbra salvage volume (PSV) was calculated as difference of penumbra and net infarct growth from admission to follow-up imaging. Results In patients with complete reperfusion (mTICI ≥ 2c), the median PSV was significantly higher than the median PSV in patients with partial or incomplete (mTICI 2a–2b) reperfusion (median 224 mL, IQR: 168–303 versus 158 mL, IQR: 129–225; p < 0.01). A higher degree of recanalization was associated with increased PSV (+ 63 mL per grade, 95% CI: 17–110; p < 0.01). Higher PSV was also associated with improved functional outcome (OR/mRS shift: 0.89; 95% CI: 0.85–0.95, p < 0.0001). Conclusions PSV may be an important mediator between functional outcome and recanalization degree in EVT patients and could serve as a more accurate instrument to compare treatment effects than infarct volumes.

scholarly journals CT perfusion in hyper-acute ischemic stroke: the acid test for COVID-19 fear

2021 ◽  
Author(s):  
Giovanni Furlanis ◽  
Miloš Ajčević ◽  
Ilario Scali ◽  
Alex Buoite Stella ◽  
Sasha Olivo ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Clinical Presentation ◽  
Ct Perfusion ◽  
Infarct Volume ◽  
Sudden Onset ◽  
Stroke Patients ◽  
Severe Clinical Presentation ◽  
Acid Test ◽  
Core Volume

Abstract Purpose The fear of COVID-19 infection may discourage patients from going to the hospital even in case of sudden onset of disabling symptoms. There is growing evidence of the reduction of stroke admissions and higher prevalence of severe clinical presentation. Yet, no studies have investigated the perfusion pattern of acute strokes admitted during the lockdown. We aimed to evaluate the effects of the COVID-19 pandemic on hyper-acute stroke CT perfusion (CTP) pattern during the first months of the pandemic in Italy. Methods In this retrospective observational study, we analyzed CTP images and clinical data of ischemic stroke patients admitted between 9 March and 2 June 2020 that underwent CTP (n = 30), to compare ischemic volumes and clinical features with stroke patients admitted during the same period in 2019 (n = 51). In particular, CTP images were processed to calculate total hypoperfused volumes, core volumes, and mismatch. The final infarct volumes were calculated on follow-up CT. Results Significantly higher total CTP hypoperfused volume (83.3 vs 18.5 ml, p = 0.003), core volume (27.8 vs 1.0 ml, p < 0.001), and unfavorable mismatch (0.51 vs 0.91, p < 0.001) were found during the COVID-19 period compared to no-COVID-19 one. The more unfavorable perfusion pattern at admission resulted in higher infarct volume on follow-up CT during COVID-19 (35.5 vs 3.0 ml, p < 0.001). During lockdown, a reduction of stroke admissions (− 37%) and a higher prevalence of severe clinical presentation (NIHSS ≥ 10; 53% vs 36%, p = 0.029) were observed. Conclusion The results of CTP analysis provided a better insight in the higher prevalence of major severity stroke patients during the COVID-19 period.

928-P: Dulaglutide Has Higher Adherence and Persistence than Semaglutide and Exenatide QW: 6-Month Follow-Up from U.S. Real-World Data

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 928-P
Author(s):  
REEMA MODY ◽  
MARIA YU ◽  
BAL K. NEPAL ◽  
MANIGE KONIG ◽  
MICHAEL GRABNER
Keyword(s):  
Real World ◽  
Real World Data ◽  
World Data ◽  
Exenatide Qw

Prior real-world experience influences non-linguistic statistical learning

2020 ◽  
Author(s):  
Stephen Charles Van Hedger ◽  
Ingrid Johnsrude ◽  
Laura Batterink
Keyword(s):  
Statistical Learning ◽  
Real World ◽  
Language Experience ◽  
Pitch Range ◽  
Test Items ◽  
Instrument Measuring ◽  
Statistical Regularities ◽  
Context Free ◽  
Specific Learning

Listeners are adept at extracting regularities from the environment, a process known as statistical learning (SL). SL has been generally assumed to be a form of “context-free” learning that occurs independently of prior knowledge, and SL experiments typically involve exposing participants to presumed novel regularities, such as repeating nonsense words. However, recent work has called this assumption into question, demonstrating that learners’ previous language experience can considerably influence SL performance. In the present experiment, we tested whether previous knowledge also shapes SL in a non-linguistic domain, using a paradigm that involves extracting regularities over tone sequences. Participants learned novel tone sequences, which consisted of pitch intervals not typically found in Western music. For one group of participants, the tone sequences used artificial, computerized instrument sounds. For the other group, the same tone sequences used familiar instrument sounds (piano or violin). Knowledge of the statistical regularities was assessed using both trained sounds (measuring specific learning) and sounds that differed in pitch range and/or instrument (measuring transfer learning). In a follow-up experiment, two additional testing sessions were administered to gauge retention of learning (one day and approximately one-week post-training). Compared to artificial instruments, training on sequences played by familiar instruments resulted in reduced correlations among test items, reflecting more idiosyncratic performance. Across all three testing sessions, learning of novel regularities presented with familiar instruments was worse compared to unfamiliar instruments, suggesting that prior exposure to music produced by familiar instruments interfered with new sequence learning. Overall, these results demonstrate that real-world experience influences SL in a non-linguistic domain, supporting the view that SL involves the continuous updating of existing representations, rather than the establishment of entirely novel ones.

Effectiveness of Dulaglutide in the Real World and in Special Populations of Type 2 Diabetic Patients

2020 ◽  
Vol 105 (7) ◽  
pp. e2617-e2625 ◽  
Author(s):  
Mario Luca Morieri ◽  
Vera Frison ◽  
Mauro Rigato ◽  
Michele D’Ambrosio ◽  
Federica Tadiotto ◽  
...  
Keyword(s):  
Body Weight ◽  
Real World ◽  
Disease Duration ◽  
Diabetic Patients ◽  
Type 2 Diabetic Patients ◽  
Body Weight Reduction ◽  
Background Population ◽  
Glucagon Like Peptide 1

Abstract Context In randomized controlled trials (RCTs) on type 2 diabetes (T2D) patients, the glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-RA) dulaglutide reduced HbA1c and body weight, but generalizability of such findings to real-world T2D patients is challenging. Objective We evaluated effectiveness of dulaglutide in routine clinical practice, especially in subgroups of patient that are underrepresented in RCTs. Design Retrospective multicenter study. Setting Diabetes outpatient clinics. Patients and intervention All consecutive patients who initiated dulaglutide between 2015 and 2018. Main outcome measures Changes in HbA1c and body weight were assessed up to 30 months after baseline. Effectiveness was analyzed in patient subgroups according to: prior use of GLP-1RA, persistence on treatment and dose, age, sex, disease duration, renal function, obesity, cardiovascular disease, or concomitant use of insulin or sulphonylurea. Results From a background population of 83,116 patients, 2084 initiated dulaglutide (15.3% switching from another GLP-1RA), 1307 of whom had at least 1 follow-up visit. Overall, dulaglutide reduced HbA1c by 1.0% and body weight by 2.9 kg at the end of observation. These effects were more pronounced in GLP-1RA-naïve patients and in those with shorter disease duration. Improvement in HbA1c was highly significant and consistent across all subgroups, including those aged ≥ 75 years, nonobese, or with chronic kidney disease. Body weight declined in all subgroups and significantly more with the 1.5-mg versus 0.75-mg dose. Conclusions In real-world T2D patients, effectiveness of dulaglutide on HbA1c and body weight reduction was highly consistent and significant even in subgroups of patients poorly represented in RCTs.

scholarly journals Real-World Outcomes of Ivacaftor Treatment in People with Cystic Fibrosis: A Systematic Review

2021 ◽  
Vol 10 (7) ◽  
pp. 1527
Author(s):  
Jamie Duckers ◽  
Beth Lesher ◽  
Teja Thorat ◽  
Eleanor Lucas ◽  
Lisa J. McGarry ◽  
...  
Keyword(s):  
Systematic Review ◽  
Cystic Fibrosis ◽  
Real World ◽  
Safety Profile ◽  
Clinical Trial Data ◽  
Patient Characteristics ◽  
Healthcare Resource Utilization ◽  
Patient Reported ◽  
Clinical Benefits

Cystic fibrosis (CF) is a rare, progressive, multi-organ genetic disease. Ivacaftor, a small-molecule CF transmembrane conductance regulator modulator, was the first medication to treat the underlying cause of CF. Since its approval, real-world clinical experience on the use of ivacaftor has been documented in large registries and smaller studies. Here, we systematically review data from real-world observational studies of ivacaftor treatment in people with CF (pwCF). Searches of MEDLINE and Embase identified 368 publications reporting real-world studies that enrolled six or more pwCF treated with ivacaftor published between January 2012 and September 2019. Overall, 75 publications providing data from 57 unique studies met inclusion criteria and were reviewed. Studies reporting within-group change for pwCF treated with ivacaftor consistently showed improvements in lung function, nutritional parameters, and patient-reported respiratory and sino-nasal symptoms. Benefits were evident as early as 1 month following ivacaftor initiation and were sustained over long-term follow-up. Decreases in pulmonary exacerbations, Pseudomonas aeruginosa prevalence, and healthcare resource utilization also were reported for up to 66 months following ivacaftor initiation. In studies comparing ivacaftor treatment to modulator untreated comparator groups, clinical benefits similarly were reported as were decreases in mortality, organ-transplantation, and CF-related complications. The safety profile of ivacaftor observed in these real-world studies was consistent with the well-established safety profile based on clinical trial data. Our systematic review of real-world studies shows ivacaftor treatment in pwCF results in highly consistent and sustained clinical benefit in both pulmonary and non-pulmonary outcomes across various geographies, study designs, patient characteristics, and follow-up durations, confirming and expanding upon evidence from clinical trials.

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