Double Vision

Nearly one million Americans seek medical care for double vision each year. If you’re seeing two images of a single object, experienced ophthalmologist Lori Dao, MD, can determine the underlying cause at the Adult Strabismus Institute in Plano, Texas. Dr. Dao brings years of expertise and specialized training in diagnosing and treating double vision to help protect your vision and overall eye health.
Call the office or book an appointment online today for timely evaluation and care.

Double Vision Q & A

What is double vision?

Double vision (diplopia) occurs when you see two images of a single object. The images may appear side by side (horizontal diplopia), one above the other (vertical diplopia), diagonally, or one image may appear tilted.
Because double vision can lead to eye pain, dizziness, headaches, or nausea, prompt evaluation is important.

Is double vision the same as blurry vision?

No. Blurry vision and double vision are different conditions.
However, very small eye misalignments may initially look more like blurry or shadowed vision. Over time, these misalignments often progress to two distinct images, revealing true double vision.

Double vision falls into two primary categories:

Binocular diplopia

This type resolves when either eye is covered. It is often caused by misaligned eyes or a muscle imbalance that prevents the eyes from working together properly.

Monocular diplopia

This type persists even when one eye is covered. It usually indicates a structural or optical issue within that eye.

What causes double vision?

Double vision can result from many different conditions—ranging from minor to serious. Determining the cause is essential for selecting the right treatment. Possible causes include:

• Refractive errors such as astigmatism

• Cranial nerve palsies

• Thyroid eye disease

• Stroke or neurological conditions

• Weak or imbalanced eye muscles

• Head injuries

While double vision can occur at any age, risk increases after age 60.

How is double vision treated?

Dr. Dao performs a comprehensive evaluation—including a visual acuity test and specialized eye alignment assessment—to determine whether your double vision is monocular or binocular and identify its underlying cause.

Treatment options may include:

Corrective lenses or prism glasses

These help align the images from each eye, reducing or eliminating double vision.

Medical or surgical management

Dr. Dao will determine the most effective treatment for your condition, which may include prism glasses, targeted eye exercises, or surgical correction when appropriate.

When should I seek emergency care?

Sudden-onset double vision—especially when paired with symptoms like a drooping eyelid, headache, weakness, or difficulty speaking—requires immediate emergency attention, as these signs may indicate a neurological emergency such as a stroke.

Persistent or newly developed double vision is never normal. Dr. Dao provides comprehensive evaluation and advanced treatment options at the Adult Strabismus Institute to help restore visual comfort and protect long-term eye health.

To schedule your appointment, call the office or book online today.