Correlation of Corneal and Scleral Topography in Cases with Ectasias and Normal Corneas
Bibliographic record
Abstract
Background and Objective To determine the relationships between corneal and scleral elevation topography in subjects with corneal ectasias and normal corneas. Material and Methods This is a multi-site retrospective study. Ocular surface topography (sMap3D, Precision Ocular Metrology, US) was collected on 115 eyes with prolate cornea profile (Group A) and 227 eyes showing corneal ectasia (Group B). Sagittal height (SAG 1) was measured in the axis of the highest elevated point of the cornea (apex), defined by the meridian joining this apex to the geometrical center of the cornea at an 16 mm chord diameter (8-mm radius). Another sag value was evaluated 180° away (SAG 2) at the same diameter/radius. The difference in height between SAG 1 and SAG 2 represents a quadrant specific effect (QSE). Conjunctival toricity is estimated by comparing the best fit of the conjunctival/scleral shape data to a toric (Sin2) curve; the root- mean-squared error (RMSE) of this curve, a measure of irregularity, was also calculated. Results The ectasia subjects demonstrated greater QSE, (p<0.001), standard toricity (p<0.001) and RMSE (p<0.001) on the sclera compared to normal cornea cases. If the apex of the ectasia was ≥1.25mm from the corneal center, the asymmetry was greater. Within the Group A, standard toricity was significantly higher than QSE (p<0.001) suggesting a more regular conjunctival pattern. As a proof, a significantly greater proportion of cases in Group B vs. Group A (57% vs. 26%, p<0.001) were found with conjunctival irregular shape, as previously defined. In both groups, subjects graded as having spherical/toric scleral shape had significantly lower RMSE values than those graded as having irregular shapes (p<0.001). Conclusion Subjects with corneal ectasia have a different scleral shape compared to those with normal corneal profiles, largely presenting as a quadrant specific effect along the same axis. This difference is higher if the apex of the ectasia is ≥1.25 mm from the corneal center. RMSE seems to correlate with scleral shape classification in both groups.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot 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.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
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.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
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".