Brain tumors and Visual Disturbances

Both benign and malignant tumors can damage the optic nerves, directly or indirectly by compressing them through increased pressure inside the skull. This can cause problems with a patient’s vision clarity, color vision and visual fields sensitivity.

Brain tumors are categorized as either primary or secondary. A primary brain tumor originates in the brain itself and is often benign. A secondary brain tumor, also known as a metastatic brain tumor, occurs when cancer cells spread to the brain from another organ.

Unfortunately, some tumors may cause damage to the brain in such a way that even after or during removal of the tumor and extensive rehabilitation, the optic nerves remain damaged.

What are the most common types of sight problems from brain tumors?

If you have a problem with your vision because of your brain tumor or as a side effect of your treatment, you can ask to be referred to our Deidre de Jongh.   We will perform a complete neuro-vision assessment and develop a rehabilitation plan and offer advice to help you carry on with your daily activities.

Common side effects of a brain tumor or its treatment:

Visual field loss, blurred vision, color vision loss, double vision, sensitivity to light, facial palsy, dry eyes & abnormal eye movements.

Visual field loss: 

The visual field is the total area you can see while looking at one point. There are many different types of field loss.Everyday tasks, such as reading, watching television and travelling safely outdoors in new areas, can become difficult. You may often feel surprised by items or people suddenly appearing or be unaware of the field defect and unconsciously neglect the missing area of vision. This can lead to bumping into things on one side, eating half a plate of food only, or only reading half a line of print.

Double vision (diplopia):

Strain in the muscle system of the eyes may cause difficulty with keep the images of both eyes aligned. Intermittent spells of blurred and double vision is caused when you have difficulty keeping the two images of a single object together. The images may be side by side, one on top of the other, or diagonal to each other. It may happen all the time, or only in certain circumstances. Double vision has a severe impact on cognitive function, concentration, memory, balance and spatial orientation.

Sensitivity to light (photo-phobia):

Your vision may become sensitive to light due to the treatment for your tumor. This could be short term or long term. Light sensitivity is experienced when your brain struggles to adjust to different levels of light. You may need to allow extra time for your eyes to adjust when moving between areas of different levels of light. This may be very uncomfortable.  

Facial palsy and dry eyes:  

Some large tumors can cause facial palsy. This can lead to dry eyes or watery eyes, difficulty closing your eyes, redness, and blurring of vision. If you cannot close your eyes, the tears in your eyes can’t be spread over the eye and the surface of the eye can be exposed for long periods of time. This can cause dry, irritated eyes and increase the risk of infection.

Abnormal eye movements:

Abnormal eye movements can come in many forms. Both your eyes may not work together to look at the same point (squint), or your eyes may wobble out of control (nystagmus). Both of these will make it harder to focus, and can cause blurry or double vision, dizziness and disorientation.  

CLICK HERE  to find out how our Vision Rehabilitation programs can assist you or a loved one if you have been diagnosed or treated for a brain tumor.