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Record W2138255487 · doi:10.1109/nssmic.1998.773925

Attenuation correction in SPECT using active surfaces

2002· article· en· W2138255487 on OpenAlexaff
Rita Noumeir, R. El-Daccache

Bibliographic record

Venue1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255) · 2002
Typearticle
Languageen
FieldMedicine
TopicMedical Imaging Techniques and Applications
Canadian institutionsÉcole de Technologie Supérieure
Fundersnot available
KeywordsAttenuationSingle-photon emission computed tomographyTomographyIterative reconstructionCorrection for attenuationSegmentationSurface reconstructionImage segmentationPhysicsBoundary (topology)SmoothnessSurface (topology)Computer visionOpticsComputer scienceMathematicsGeometryMathematical analysisNuclear medicine

Abstract

fetched live from OpenAlex

To compensate for the photon attenuation in SPECT, we propose to determine the boundary of the uniform attenuation map by detecting the surface of the patient body from the emission data. We use an active surface model which is a three dimensional generalisation of the active contour model known as snakes. The model is an elastic surface that is deformed under the action of internal and external forces. The internal forces model the smoothness constraints while the external forces model the image constraints. In our case, the image constraints are three-dimensional detected edges obtained using the Zucker and Hummel operator applied on the emission volume. The finite difference method is used to solve the energy-minimisation problem for a surface. The segmentation of the patient body from the emission tomography reconstruction is compared to the segmentation from the transmission tomography reconstruction. Moreover, tomography reconstruction corrected for the non-uniform attenuation is compared to the tomography reconstruction corrected for the uniform attenuation. Uniform attenuation correction is performed using the boundary detected from the emission data.

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: Bench or experimental · Consensus signal: none
GenreCandidate signal: Methods · Consensus signal: Methods
Teacher disagreement score0.001
Threshold uncertainty score0.005

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.004
Meta-epidemiology (narrow)0.0010.001
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0010.001
Science and technology studies0.0000.001
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0010.001

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 head0.028
GPT teacher head0.294
Teacher spread0.266 · 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 designBench or experimental
Domainnot available
GenreMethods

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

Citations7
Published2002
Admission routes1
Has abstractyes

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Same venue1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255)Same topicMedical Imaging Techniques and ApplicationsFrench-language works237,207