Visual Impairment
Type: Symptom
Definition
A progressive, irreversible loss of sight leading ultimately to complete blindness.
Clinical Details
Microfilariae actively migrate into all structures of the eye, from the cornea to the optic nerve. Their eventual death in these avascular tissues releases highly inflammatory Wolbachia antigens, causing punctate keratitis, sclerosing keratitis, and profound optic neuritis. This cumulative, lifelong scarring process is the mechanism behind 'river blindness'.