What causes double vision in the eyes?

Under normal circumstances, double vision may be caused by astigmatism, medication side effects, macular edema, floaters, cataracts, or other reasons. If any discomfort occurs, it is recommended to seek immediate medical attention. Specific analysis is as follows:

1. Astigmatism: Astigmatism occurs when the cornea and lens have different refractive powers in different directions, causing incoming light to fail to focus precisely on the retina, instead forming a blurred spot of light. This typically causes patients to see double or blurry images when viewing objects. It can be improved by wearing appropriate corrective glasses or contact lenses.

2. Medication side effects: Certain medications affecting the nervous system may lead to visual abnormalities, including double vision. This could result from the drug affecting the coordination of eye muscles or the brain's ability to process visual information. Patients should consult their doctor promptly; dosage adjustments or alternative medications may be necessary.

3. Macular edema: Macular edema refers to swelling in the macula—the central area of the retina—resulting in impaired function of photoreceptor cells. This disrupts the transmission and processing of visual signals and may cause double vision. Follow medical advice to manage the condition with medications such as acetazolamide tablets, dexamethasone sodium phosphate injection, or triamcinolone acetonide acetic acid injection.

4. Floaters: Floaters are a common ophthalmic condition characterized by small moving dark spots in the field of vision, resembling flying mosquitoes. These may arise from vitreous opacity or liquefaction; the cloudy vitreous moves within the eye and casts shadows on the retina, creating the sensation described. Treatment under medical guidance may include polyvinyl iodine complex capsules, vancomycin hydrochloride for injection, or ceftazidime for injection to alleviate symptoms.

5. Cataracts: Cataracts occur due to clouding of the eye’s natural lens. As the degree of lens opacity increases, its refractive ability becomes compromised, preventing light from properly focusing on the retina and resulting in double vision. Management may include medications such as pirenoxine eye drops, phacolysin eye drops, or glutathione tablets, based on physician recommendations.

In daily life, maintain proper eye usage habits and adjust indoor lighting appropriately to avoid excessively bright or dim conditions that may irritate the eyes.