Ghosting in vision refers to seeing a duplicate or overlapping image of a single object, often appearing as a faint shadow or halo. This differs from true double vision (diplopia), where two distinct images are perceived. Ghosting typically involves a less defined, shadowy replication that can make daily tasks challenging. Understanding its various causes is important for proper management.
Common Ocular Causes
Astigmatism stands as a frequent cause of ghosting, where the eye’s cornea or lens has an irregular, often football-like shape instead of a perfectly round one. This irregularity causes light to scatter unevenly as it enters the eye, preventing it from focusing precisely on the retina. As a result, a faint, shadowy duplicate of the image can appear next to the primary one.
Insufficient or poor-quality tear film, characteristic of dry eye syndrome, can also lead to ghosting. When the eye’s surface lacks proper lubrication, it becomes uneven, scattering light rays and creating a shadowy overlap. This ghosting often worsens during activities like reading or prolonged screen use, as blinking decreases. Uncorrected refractive errors, such as farsightedness or nearsightedness, can sometimes contribute to ghosting, especially when the eye strains to focus.
Simple eyewear issues can also induce ghosting. Dirty or scratched eyeglass lenses, or an outdated prescription, can distort light transmission. Similarly, contact lenses that do not fit properly, shift, or dry out can lead to blurred or ghosted vision. Prolonged digital device use can induce digital eye strain, which often includes dry eyes, temporarily contributing to ghosting.
Corneal and Lens-Related Conditions
Structural changes within the eye’s cornea or lens can contribute to ghosting. Keratoconus, a progressive eye disease, involves the thinning and outward bulging of the cornea into a cone-like shape. This altered shape distorts how light enters the eye, leading to significant and irregular ghosting, along with blurred vision.
Cataracts, the clouding of the eye’s natural lens, commonly cause ghosting. As proteins within the lens clump together, they scatter light rather than allowing it to pass clearly, projecting multiple incomplete images onto the retina. This effect is particularly noticeable around lights and can also manifest as glare or blurred vision, especially in early stages. Any irregularities or scars on the cornea, resulting from injuries, infections, or prior eye surgeries, can disrupt the passage of light. These imperfections can cause light to scatter or refract improperly, leading to ghosting by creating secondary, fainter images.
Neurological and Systemic Factors
Ghosting can stem from conditions beyond the eye, involving the nervous system or broader systemic health. Neurological conditions, such as multiple sclerosis, stroke, or brain tumors, can manifest with visual disturbances like ghosting. These issues often arise from impaired coordination of eye muscles or disruptions in nerve pathways that transmit visual information to the brain. While less common, these underlying neurological issues can affect how images are processed, leading to ghosting.
Systemic diseases can also influence vision. Uncontrolled diabetes, for instance, can damage retinal blood vessels or affect nerves controlling eye movements, potentially causing visual anomalies including ghosting. Thyroid eye disease, an autoimmune condition, can lead to inflammation and swelling around the eyes, impacting eye alignment and movement, which may result in ghosting. Some medications can also list visual disturbances, including ghosting, as a side effect.
When to Consult a Professional
Seek professional medical attention if ghosting appears suddenly or rapidly worsens. This is especially true if accompanied by other concerning symptoms such as severe eye pain, persistent headaches, or significant blurriness. Any new onset of ghosting that does not resolve quickly warrants evaluation.
Consult an eye care professional if ghosting persists despite addressing common issues like dry eyes or updating eyeglasses or contact lenses. Red flags necessitating immediate consultation include true double vision (diplopia), any loss of vision, changes in eye movement, nausea, vomiting, or signs of neurological dysfunction like weakness or numbness. A comprehensive eye examination can help determine the underlying cause and ensure appropriate management.