Eye charts measure visual acuity to determine whether glasses or contacts are needed. Visual acuity describes central vision's ability to see detail. Test typically performed 6 meters from chart with one eye covered
Eye floaters are deposits in the vitreous humor, appearing as moving spots in vision. Vitreous gel becomes clear at birth, but deposits develop with age. Floaters appear as black spots, lines, cobwebs or "O" or "C"-shaped blobs
Photopsia, or seeing stars, occurs when retina is compressed by eye pressure. Pressure from sneezing, coughing, or straining can trigger phosphenes. Posterior vitreous detachment is a normal aging-related condition. Migraine headaches often cause visual disturbances lasting 20-30 minutes. Stress can trigger photopsia through cortisol release and pupil dilation
Photopsia can cause flashes of light, streaks of lightning, or stars. Common causes include retinal detachment, vitreous detachment, and diabetic retinopathy. Some medications like digoxin and chloroquine can trigger flashes
Eye color changes are rare and can be influenced by environment and lighting. Changes can be harmless or indicate serious conditions
Funduscopy is the examination of the eye's posterior structures. It is a routine part of all eye examinations, not just ophthalmologists. Funduscopy can be performed directly (direct) or indirectly (indirect)