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Record W4205812301 · doi:10.1002/alz.054582

A retinal deep phenotyping<sup>TM</sup> platform to predict the cerebral amyloid PET status in older adults

2021· article· en· W4205812301 on OpenAlexaff
Jean‐Paul Soucy, Claudia Chevrefils, Sam Osseiran, Jean‐Philippe Sylvestre, Frédéric Lesage, Sylvain Beaulieu, Tharick A. Pascoal, Karine Provost, Jean Daniel Arbour, Marc‐André Rhéaume, Sylvia Villeneuve, Ziad Nasreddine, Pedro Rosa‐Neto, Serge Gauthier, Alain Robillard, Céline Chayer, Sandra E. Black, Peter J. Kertes, Hossam El Shahawy, Christopher J.M. Scott, Aparna Bhan, Ralph N. Martins, Tejal Shah, Sunil M. Gupta, Kirsten Calvin, Gregory Hsu, Val J. Lowe, John J. Chen, Aaron Ritter

Bibliographic record

VenueAlzheimer s & Dementia · 2021
Typearticle
Languageen
FieldMedicine
TopicRetinal Imaging and Analysis
Canadian institutionsHealth Sciences CentreUniversity of TorontoClinique Paro ExcellenceDouglas Mental Health University InstituteHôpital Maisonneuve-RosemontPolytechnique MontréalConcordia UniversityCentre Hospitalier de l’Université de MontréalMcGill UniversitySunnybrook Health Science CentreOptina Diagnostics (Canada)Greenfield Research (Canada)Montreal Neurological Institute and Hospital
Fundersnot available
KeywordsRetinalHyperspectral imagingNeuroimagingArtificial intelligenceDementiaSupport vector machinePattern recognition (psychology)Positron emission tomographyRetinaComputer scienceClassifier (UML)NeurosciencePathologyMedicinePsychologyDiseaseOphthalmology

Abstract

fetched live from OpenAlex

Abstract Background As the only optically accessible part of the central nervous system, the retina represents an intriguing opportunity for the detection of biomarkers for Alzheimer’s disease (AD). This study evaluated the performance of the Retinal Deep Phenotyping TM platform, a digital biomarker platform comprising a hyperspectral retinal camera and image analysis algorithms, for the detection of likely positron‐emission tomography (PET) amyloid status (negative or positive) in older adults. A set of phenotypic features that correlates with the cerebral amyloid status as determined by amyloid PET scan were identified and used to train a classifying algorithm. Method Hyperspectral retinal images acquired with a Mydriatic Hyperspectral Retinal Camera from 194 participants (age ≥ 50 years), including cognitively normal and cognitively impaired (mild cognitive impairment and dementia) across 5 imaging sites were processed in order to train the model. Of these 194 participants, 73 individuals (38%) were amyloid‐positive, as confirmed by unanimous readings of PET scans by a panel of 3 expert reviewers. The pre‐processed hyperspectral images were segmented into various anatomical sites, and a texture‐based approach was used to extract several thousands of spatial‐spectral features. The most relevant features for the classification task were selected using a minimum redundancy maximum relevance (MRMR) algorithm and used to train a linear support vector machine (SVM) classifier. A nested, cross‐validation technique was used to evaluate the performance of the classifier. Result The resulting model based on the 17 most significant features showed high performance to discriminate between amyloid positive and negative subjects with an area under the receiver operating curve (AUC ROC ) of 0.87 (95% CI: 0.83 – 0.92). Conclusion The Retinal Deep Phenotyping TM platform shows promise for detecting the likely cerebral amyloid PET status in adults 50 years and older from a simple, non‐invasive retinal scan and could provide an accessible means to identify individuals with abnormal cerebral amyloid in a clinical or drug development context. This phenotyping platform provides a flexible approach that could also be used for the detection of multiple biomarkers involved in cognitive decline from the same hyperspectral images of the retina.

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 distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.193
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0010.000

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 head0.013
GPT teacher head0.260
Teacher spread0.247 · 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 teacher head, not a consensus.

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

Citations2
Published2021
Admission routes1
Has abstractyes

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