- See Pupil
- Preparation
- Use a bright flashlight
- Perform in a semi-dark room (but light enough to see bilateral pupil reaction)
- Move the flashlight from directly in front of one eye, to directly in front of the other
- Maintain a constant distance between flashlight and eye
- Avoid maintaining a central point at nose (stimulates near response)
- Check left eye response (direct and consensual)
- Shine light on left eye for 3 seconds and check left pupil reflex
- Shine light on right eye for 3 seconds and check left pupil reflex
- Check right eye response (direct and consensual)
- Shine light on right eye for 3 seconds and check right pupil reflex
- Shine light on left eye for 3 seconds and check right pupil reflex
- Normal response
- Abnormal - Afferent lesion (RAFD, Marcus Gunn Pupil)
- Findings: Relative Afferent Pupillary Defect (RAFD)
- No pupil response to direct light
- Intact Consensual Light Reflex (when light shone in opposite eye)
- Paradoxical Pupil Dilation to direct light
- Occurs on moving light from opposite to affected eye (Swinging Flashlight Test)
- Causes: Optic Nerve Lesion (rarely at Retina)
- Ischemic Optic Neuropathy
- Optic Neuritis (e.g. Multiple Sclerosis)
- Optic Nerve compression or Trauma
- Glaucoma (asymmetric)
- Other Optic Neuropathy (e.g. infiltrative, radiation, infectious)
- References