PupilMetrics Windows Versiondaprof2026-02-20T21:33:27+00:00
“PupilMetrics Research” and “PupilMetrics Neuro” implements Professor Bryan K. Marcia’s clinical and historical research protocols.
Core Algorithm Components
Iris Detection
Uses grayscale image processing to locate the iris boundary
Employs a circle-scoring algorithm that searches for the strongest edge gradient
Two-pass detection: coarse search followed by fine refinement
Returns center coordinates, radius, and confidence score
Pupil Detection
Searches within the inner portion of the detected iris
Uses adaptive thresholding based on the darkest 30% of pixels
Fits an ellipse to the dark region using covariance matrix eigenvalue decomposition
Extracts boundary points by ray-casting from center outward
Returns center, major/minor axes, orientation angle, and boundary points
Pupil Boundary Analysis
Analyzes 72 boundary points (every 5 degrees) around the pupil edge
Calculates deviation from the average radius at each clock position
Groups deviations by clock hour (12 zones)
Identifies flattenings (inward deviations) and protrusions (outward deviations)
Searches for gradient changes between pupil edge and mid-iris
Identifies the collarette boundary
Calculates ANW ratio relative to iris diameter
Algorithm updates include:
SHIFTS (Drawing Out)
Which zone the collarette bulges toward
Clinical correlation based on Velhover
CONSTRICTIONS (Drawing In) Frontal zone constricted S: Middle-temporal shift. ← Drawing OUT (protrusion), S: Frontal and basal zones are constricted. ← Drawing IN (narrowing) (ML detected 78% of pathological cases!)
Basal zone constricted
Combined “Frontal and basal” pattern
Both in Same Eye
Correctly reports both when present
Matches Bexel output format exactly
What We Now Have:
ANW Ratio – Bexel-compatible calculation (25-35% normal)
ANW Form Type – Regular, Drawn In, Drawn Out
ANW Asymmetry – Per-sector variance detection
Zone Constrictions – “Frontal zone constricted” style reporting
Pattern Correlation – Compare pupil and ANW findings by sector
Key Measurements Produced
Parameter
Description
Normal Range
P/I Ratio
Pupil diameter as % of iris diameter
20-30%
Ellipseness
Minor/major axis ratio
>95% normal
Circularity
How circular the pupil boundary is
>95% normal
Decentralization
Pupil center offset from iris center
<5% normal
Deformation
Maximum boundary deviation
<5% normal
ANW Ratio
Autonomic nerve wreath position
25-35% normal
Clinical Interpretation FeaturesPupil Form Types applied in Velchover system (PupilMetrics Neuro Version)
Circle – Normal
Oval-Vertical – Circulatory cerebral disturbances with danger of hemorrhage