Detecting blindness involves assessing a person’s ability to perceive light, shapes, and details. Here are key methods:
1. Observation of Symptoms
- Total blindness: No perception of light.
- Partial blindness: Blurry vision, tunnel vision, or difficulty seeing in low light.
- Signs in infants: No eye contact, lack of response to visual stimuli, unusual eye movements.
2. Simple Home Tests
- Light Perception Test: Shine a flashlight into the eye and check for a reaction.
- Object Tracking: Move an object in front of the person’s eyes and observe if they follow it.
3. Clinical Tests
- Visual Acuity Test: Uses an eye chart to measure clarity of vision.
- Pupillary Light Reflex Test: Checks if pupils respond to light.
- Electroretinogram (ERG): Measures electrical responses in the retina.
- Ophthalmoscopy: Examines the retina for damage.
- MRI or CT Scan: Detects brain or optic nerve issues affecting vision.
If blindness is suspected, an ophthalmologist should evaluate the condition immediately for diagnosis and possible treatment.