Anisocoria is the difference in pupil size between the right and left eye, expressed as an absolute percentage difference in PI ratio.
| Absolute difference | Severity | Clinical note |
|——————–|———-|————–|
| < 2% | **None** — within normal limits | Physiologically symmetric |
| 2–4% | **Mild** | May be physiological; monitor |
| 4–8% | **Moderate** | Notable asymmetry; flagged for observation |
| > 8% | **Severe** | Significant asymmetry; research observation flagged |
Moderate and severe anisocoria activates a TBI (Traumatic Brain Injury) indicator flag, which is noted in the results and PDF report. This flag is a research observation reference, not a diagnostic finding.
The larger pupil (OD or OS) and the absolute difference are displayed in the bilateral comparison card.
