Demystifying dizziness

	Written by Eric Ikeda, O.D., F.C.O.V.D., DPNAP, a member of the AOA's Vision Rehabilitation Committee.

In recent years, it is apparent that both the medical community and the public have become increasingly concerned with traumatic brain injury, including sports-related injuries or concussions. As a result, optometrists have seen a significant number of patients who suspect their injury has resulted in their many visual symptoms, including blurred vision, double vision, difficulty reading or viewing their electronic device, problems with balance and movement, disorientation in busy environments, and dizziness.

The Centers for Disease Control and Prevention report that millions of Americans visit the emergency room due to traumatic brain injury. Many patients are subsequently admitted for care and often receive comprehensive rehabilitation therapy services, including occupational, physical, speech and cognitive therapy. Frequently during their therapies, many of these patients report having persistent symptoms of balance difficulties and dizziness. As a result, the patients are referred to the optometrist for a vision examination. Therefore, it is important for optometrists to become familiar with the various causes of dizziness and to understand the relationship between the visual, vestibular and somato-sensory systems. By asking the right questions during the case history, you can then effectively evaluate and manage these patients.

Questions to ask and considerations

Dizziness is not a disease. It is a form of physical impairment where a person's spatial perception and stability are compromised. It is often reported when there exists an abnormal spatial sense, which is commonly associated with brain injury and stroke, the latter frequently found to contribute to the sense of poor balance and visuo-spatial changes.

The following are common causes to consider when a patient complains of dizziness:

1. Vertigo.
2. Side effects of certain medications (anti-seizure and anti-depressants).
3. Anemia.
4. Hypotension.
5. Hypoglycemia.
6. Migraines.
7. Hormonal changes.
8. Pregnancy.
9. Motion sickness (motor vehicles, ships, airplanes).
10. Panic attack.
11. Heart attack (initial onset).
12. Disorientation with head movements.
13. Age-related changes.
14. Decompensating phoria.

As optometrists, we all recognize the importance of the visual system in every functional aspect of life. Vision requires a dynamic interaction with our environment that provides accurate feedback mechanisms that help guide our actions in all that we do. During your exam, always take a careful, detailed case history since it will certainly yield information that provides helpful differentials for dizziness.

1. Current medications being taken?
2. Any caffeine/alcohol intake or nicotine use?
3. Any known drug or environmental allergies?
4. Is there a history of migraines?
5. Any history of head trauma?
6. Any dizziness when walking in the store aisle, in crowds, large open spaces, moving vehicle, with repetitious patterns?
7. History of anxiety or depression?
8. Any hearing loss?

If the patient reports the "room is spinning" or having the "feeling in my head," consider vertigo (diagnosis code R42; benign paroxysmal positional vertigo vs. vestibular dysfunction). A feeling of loss of consciousness may indicate pre-syncope (diagnosis code R55). Any "unsteady or off-balance feeling" (feet vs. head), consider possible vestibular dysfunction. Any vague symptoms, such as feeling disconnected or light-headed, may possibly indicate anxiety or depression, which are commonly seen in mild traumatic brain injury.

Examination strategies

During your comprehensive vision examination, carefully observe the patient for any unusual head or body posture (when walking to your exam room and while seated). Try to remember that following a traumatic brain injury, many patients experience an abnormal spatial sense. The symptoms encountered include poor balance and posture (tendency to bump into objects, having a lateral bias while walking, dizziness, and a sense of feeling "out of sync" with their environment). Ciuffreda and Ludlam reported that patients with abnormal visual spatial sense have visuo-motor problems associated with walking and eye-hand coordination and a misperception of depth perception of objects in the environment due to abnormal egocentric localization. This abnormal visual spatial sense is one of the common sequelae in Post Trauma Vision Syndrome.

As optometrists, we are in a unique position to effectively manage many causes of dizziness. For example, there may be adverse effects of progressive lenses, particularly induced peripheral distortion, which significantly impacts patients who have had a traumatic brain injury. Consider alternatively prescribing single vision lenses. Also, when suspecting visual spatial difficulties, consider applying binasal occlusion and ask the patient to report what he/she observes while walking around your office. During binocular function testing, you may well find that the patient has a vertical heterophoria. Doble and Feinberg had found that at least 43 of their traumatic-brain-injured patients presented with vertical heterophoria that was effectively managed with vertical prism.

It is very likely that you will encounter a patient who complains of dizziness. A careful case history with straightforward examination strategies will help you feel more comfortable and confident to manage these patients effectively.

Disclaimer: The information contained in this article represents the opinion of the author and not the AOA. These are not clinical practice guidelines, nor has the evidence been peer reviewed.

There are additional aspects to this topic that may not be presented, or considered, based on the specifics of the case.