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Abstract 14021: Angiographic and Hemodynamic Features of Symptomatic Vertebrobasilar Disease: Baseline Data from the VERiTAS Study

2014· article· en· W2197154445 on OpenAlexaff
Sepideh Amin‐Hanjani, Xinjian Du, Linda Rose‐Finnell, Dilip K. Pandey, DeJuran Richardson, Hui Xie, Keith R. Thulborn, Mitchell S.V. Elkind, Gregory J. Zipfel, David S. Liebeskind, Frank L. Silver, Jeffrey Kramer, Scott E. Kasner, Louis R. Caplan, Colin P. Derdeyn, Philip B. Gorelick, Fady T. Charbel

Bibliographic record

VenueCirculation · 2014
Typearticle
Languageen
FieldMedicine
TopicCerebrovascular and Carotid Artery Diseases
Canadian institutionsUniversity of Toronto
Fundersnot available
KeywordsMedicineStenosisStroke (engine)CardiologyVertebrobasilar insufficiencyBasilar arteryInternal medicineVertebral arteryHemodynamicsCohortRadiology

Abstract

fetched live from OpenAlex

Introduction: Atherosclerotic vertebrobasilar disease (VBD) is a significant etiology of posterior circulation stroke. In addition to thromboembolism, regional hypoperfusion is considered an important potential contributor to stroke risk. To examine the role of hemodynamic compromise in VBD, a prospective observational multi-center study, Vertebrobasilar Flow Evaluation and Risk of Transient Ischemic Attack and Stroke (VERiTAS), has recently been conducted. Here we report baseline features and vessel flow measurements from the study cohort. Methods: Baseline demographic and clinical data was collected in patients with recent vertebrobasilar TIA or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral and/or basilar arteries. Large vessel flow in the vertebrobasilar territory was assessed using quantitative MRA (QMRA). Results: The cohort (n=75, 56% male) had a mean age of 65.5 (range 40 to 90) years; two thirds presented with ischemic stroke. Hypertension (93%) and hyperlipidemia (79%) were the most prevalent vascular risk factors. Vertebral and basilar artery flows correlated negatively with degree of stenosis in the affected vessel, and positively to the minimal diameter at the site of stenosis (p<0.01). A threshold effect was evident, with affected vessel flows dropping significantly in patients with ≥70% stenosis or occlusion (p<0.05). Tandem disease involving the basilar and either or both the vertebrals had the greatest impact on immediate downstream flow in the basilar artery (38 ml/min vs. 74 ml/min, p<0.01). Assessment of distal flow status, incorporating collateral flow, however correlated neither with multifocality of disease nor severity of the maximal stenosis. Conclusions: Flow in stenotic posterior circulation vessels correlate with residual diameter and stenosis and drop significantly in the setting of tandem disease. However, distal flow status, incorporating collateral capacity, is not well predicted by the severity or location of the disease. Final clinical outcome results from the ongoing VERiTAS study will further clarify the relevance of anatomic stenosis and hemodynamic assessment to predicting stroke risk in patients with vertebrobasilar disease.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.002
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.011
Threshold uncertainty score0.021

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.002
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0010.001
Science and technology studies0.0000.000
Scholarly communication0.0010.000
Open science0.0000.000
Research integrity0.0010.000
Insufficient payload (model declined to judge)0.0020.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.016
GPT teacher head0.255
Teacher spread0.239 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations0
Published2014
Admission routes1
Has abstractyes

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