Based on symptom severity:
01. Mild: Patients exhibit mild subjective symptoms, sometimes unnoticed, with mild damage visible under slit lamp microscopy.
02. Moderate: Patients experience moderate to severe subjective symptoms, with visible damage to the ocular surface, but recovery is possible with treatment.
03. Severe: Patients have moderate to severe subjective symptoms and visible ocular surface damage. However, complete recovery of ocular surface damage may not be achievable after treatment.
