More recently, a growing number of clinicians are utilizing the VOR Cancellation test. As we discussed last week, the VOR stabilizes our vision on a target during head movement. However, there are times when the brain needs to suppress or “cancel” the VOR, during times of combined tracking and VOR tasks. An example of this would be tracking an object at the same time the individual is rotating the eyes and head together.
The VOR Cancellation test is associated with cerebellar function1. More recently, however, it has been associated with provocation of symptoms following a concussion in a study at UPMC2 as well as in preliminary findings by the Banner Concussion Center in Phoenix, AZ3.
How is it tested? This test is typically performed in sitting but it is recommended that the athletic population perform in standing with feet together. The arms are outstretched, hands clasp together and “thumbs up.” The patient is asked to visually fixate on their thumbs while rotating their trunk side to side; their eyes, head and trunk moving together. Ask the patient to perform 10 times moving in a range of 30 degrees side to side, completing a full 60 degree sweep at 40 bpm or in about 1.5 seconds.
*The course Bridgett Wallace, PT, DPT refers to in the video is the
Visual Vestibular Functional Integration (V2FIT) Certification Course
Keep in mind that this test is considered a cerebellar test and typically athletes post-concussion will be able to smoothly and timely follow the target (without corrective saccades) but frequently have an increase in symptoms. This test can be made more difficult by performing on an unstable surface (e.g., foam) or at faster and bigger speeds4.
Note: No provocation of symptoms was noted in the balance test of the VOMS4. Keep in mind, however, that balance testing with the head still is less sensitive to peripheral vestibular (inner ear) dysfunction, while the head shake test with eyes closed during postural stability testing (e.g., feet together on firm and foam) does require a higher demand on the inner ear5.
1. Leigh R and Zee D. The Neurology of Eye Movements. 4th ed. New York: Oxford University Press; 2006.
2. Mucha A, Collins M, Elbin R, Furman J and et al. A brief Vestibular/Ocular Motor Screening (VOMS) assessment to evaluate concussions: preliminary findings. American Journal of Sports Medicine 2014;42(10):2479-86.
3. Concussion Balance Test (COBALT). Unpublished raw data. Banner Concussion Center, Phoenix, AZ.
4. Mucha A, Collins M, Elbin R, Furman J and et al. A brief Vestibular/Ocular Motor Screening (VOMS) assessment to evaluate concussions: preliminary findings. American Journal of Sports Medicine 2014;42(10):2479-86.
5. Honaker J, Converse C and Shepard N. Modified head shake computerized dynamic posturography. American Journal of Audiology 2009;18(2):108-13.
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