Double vision does not always appear as two distinct objects to a person; instead, it can appear as shadows and sometimes visual blur. True double vision occurs when the eyes do not point at the same direction at the same time. Misalignment between the eyes can be a result from eye muscle weakness or imbalances, or difficulties from the nerve that controls the muscle. The nerves that control fine-tune eye muscle movement are small and can easily be affected by changes in systemic health, including diabetes, myasthenia gravis, multiple sclerosis. Patients can also get monocular or one-eyed double vision from retina problems or severe dry eye syndrome.
Signs and Symptoms often Associated with Double vision
- Awkward head tilts adapted by people to minimize the disruptive effect of seeing two images. This is a more common feature of people who have long-standing history of double vision. Some people have mild tilts but will complain about one-side neck pains.
- Visual fatigue or fluctuations which often increase with stress.
- Visual headaches or soreness around the eyes and frontal brow.
Our practice also frequently sees patients who have eye coordination difficulties following a stroke or concussion. A large portion of the brain’s surface is dedicated to eye movement, visual perception, and control so any compromises to the brain’s health can result in inconsistent and fluctuating vision. Double vision in these cases are typically a result of loss of general control to eye teaming or cranial nerve palsy (the nerves that control the eye muscles). It is important to rule out tumors and aneurysms as causes.
Treatment for Double Vision
Some causes of double vision, especially those cause by systemic health problems, may resolve on their own once the health concern is addressed. Close observation is frequently recommended so that we ensure that patients do not develop inefficient strategies for using their vision.
Long-term full opaque patching of one eye is not advised. Removing all input from the visual world of one eye makes it far more difficult for previous two-eyed individuals to judge depth and space resulting in much higher risk for falls and other complications.
Vision rehabilitation can be used as a tool to help patients develop more efficient eye movements and help their vision integrate more effectively with other sensory systems like the vestibular balance centers in their ear for orientation. It is an effective tool to train the visual system regardless of the cause of double vision. To read more about vision rehabilitation, please check out some of older blogs.
Prism glasses can be prescribed in some cases for double vision either to compensate and align images to where the eyes are pointing. Small amounts of vertical prism are incredibly effective at alleviating strain from vertical imbalances of eye muscles. Prism glasses can also be used as tools to disrupt the visual system and penalize certain aspects of processing giving patients an opportunity to develop an alternative strategy. It is important to note that prisms are used conservatively since they do cause optical blur.
It is important to be rule out all systemic causes of double vision even when seeking an eye care provider to manage double vision.