MétaCan
Menu
← Back to cohort
Record W2911298539 · doi:10.1161/str.50.suppl_1.wmp23

Abstract WMP23: Automated Regional Density Measurements on Baseline Non-Contrast CT Predict Final Infarction in Acute Ischemic Stroke Patients

2019· article· en· W2911298539 on OpenAlexaffabout
Wolfgang G. Kunz, Nils D. Forkert, Steffen Tiedt, Frank A. Wollenweber, Lars Kellert, Thomas Liebig, André Kemmling, Paul Reidler

Bibliographic record

VenueStroke · 2019
Typearticle
Languageen
FieldMedicine
TopicAcute Ischemic Stroke Management
Canadian institutionsUniversity of Calgary
Fundersnot available
KeywordsMedicineHounsfield scaleInfarctionStroke (engine)Contrast (vision)Receiver operating characteristicCardiologyNuclear medicineLinear regressionRadiologyArea under the curveCohortInternal medicineComputed tomographyMyocardial infarctionArtificial intelligenceStatistics

Abstract

fetched live from OpenAlex

Introduction: Early ischemic changes on non-contrast CT (NCCT) can be visually assessed using the Alberta Stroke Program Early CT Score (ASPECTS). We sought to determine if automated regional density quantification provides additional information on the development of final infarction. Methods: We selected 121 patients with middle cerebral artery stroke due to large vessel occlusion out of a consecutive cohort. Densities in ASPECTS regions were quantified as average Hounsfield Unit (HU) values using automated segmentation (Fig. 1). Relative HU (rHU) values were calculated dividing absolute regional densities of ischemic by non-ischemic hemispheres. Final infarction was quantified semi-automatically as total volume and was defined visually per ASPECTS region in a dichotomized fashion. A composite rHU score incorporating values from all ASPECTS regions weighted by regional relevance was calculated. ROC analysis was performed to calculate AUC values. Linear regression analysis was used for multivariable adjustment. Results: Median visual ASPECTS on NCCT was 8 (IQR: 6-9). Automated density measurements were feasible in all 121 patients within one minute of post-processing time. rHU values yielded significant regional classification of final infarction in ROC analyses for all ASPECTS regions except M3 and M6. Best classifications were achieved for lentiform nucleus (AUC=0.810, p<0.001), caudate nucleus (AUC=0.777, p<0.001), and insula (AUC=0.764, p<0.001). The composite rHU score was independently associated with final infarction volume (β=-0.353, p<0.001), outperforming visual ASPECTS assessment (β=-0.190, p=0.062) in multivariable regression analysis. Conclusions: Automated NCCT density changes identify ASPECTS regions that develop final infarction in stroke patients. The composite rHU score outperformed visual ASPECTS interpretation in the prediction of final infarction volumes and may serve as an observer-independent imaging biomarker.

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)0.004
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 score0.002
Threshold uncertainty score0.006

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.004
Meta-epidemiology (narrow)0.0010.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0010.001
Science and technology studies0.0000.000
Scholarly communication0.0010.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0020.001

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 head0.020
GPT teacher head0.258
Teacher spread0.238 · 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
Published2019
Admission routes2
Has abstractyes

Explore more

Same venueStroke→Same topicAcute Ischemic Stroke Management→French-language works237,207→