Posturography --> another abnormal result

Hecox recently had me do 3 tests: tympanometry, acoustic reflexes, and posturography (EquiTest machine). The first two came back normal.

Posturography had two parts: Sensory Organization Test and Adaptation Test. The second one was normal. The SOT “isolates and quantifies abnormalities in the patient’s use of the three sensory systems that contribute to postural control (somatosensory, visual and vestibular), as well as the brain’s integration of these inputs.”

Now it gets interesting. “The following performance attributes were in the abnormal range:
(1) The PREF is the degree to which the patient usual visual information to maintain balance, even when it is incorrect or unstable (moving visual environments).
(2) SOT Conditions: 3, 6.
(3) COG position.”

COG is “center of gravity” (what they also call “cone of stability”). And by the way, here’s something I found that’s quite interesting about the implications of abnormalities in SOT parts 3 and 6:

“Abnormalities on SOT conditions 3 and 6 indicate a preference for accurate visual information (visual predominance). When a subject is given erroneous visual cues, the subject who is visually dominant (visual preference) cannot suppress inaccurate information, which means balance is disrupted.”

So presumably, I DO experience a problem with visual dependence. Is that not accurate?

Anyway, I am including a scan of the actual SOT results page, if anyone knows how to read or interpret this stuff.

Hi George,
Check out Dr. Hain’s view of the Posturography test:

tchain.com/otoneurology/test … raphy.html

I’m not sure what these results mean in the context of coming to a solid diagnosis for you. When will you be discussing this with your doc? Definitely keep us posted. Hang in there…

Best,
Lisa

Thanks Lisa, I’d already read Hain’s discussion of it but I appreciate you mentioning it nonetheless.

Interesting one-sentence summary of the SOT: The sensory organization test evaluates whether a patient with a balance disorder DOES utilize visual, vestibular and somatosensory cues, and picks the appropriate cue under conflicting conditions to maintain balance.

Also of significant interest to me in relation to my result: The vestibular dysfunction pattern is seen in bilateral vestibular loss or decompensated unilateral vestibular loss. In these cases, the equilibrium scores are expected to be within the normal range for conditions 1 through 4 [as it was with me] , but below the lower limit of the range for conditions 5 or 6 (or both) [may apply to me somewhat].

I don’t know what some portions of the raw data refer to, but I have found some more info. For example, in the 3rd subtest (Sensory condition 3), the support surface (the foot platforms) are kept fixed, but the visual surround is angled forward – sway-referenced. And the final and most challenging subtest, Sensory condition 6, uses both a tilted support-surface and a forward-tilted visual surround, so both are sway-referenced.

In the “Sensory Analysis” graph:
(1) The score is high for the Somatosensory ratio, which effectively means there’s no dysfunction of the somatosensory system.
(2) The score is high for the Visual ratio, and so this rules out the idea of poor processing of visual cues.
(3) The score for the Vestibular ratio is marginally high (about 65 or 70 out of 100), which makes it a bit difficult to determine what significance this figure has, if any. Low scores are thought to suggest a vestibular-system dysfunction.
(4) The Vision preference ratio is fairly high (about 85/100), though this result is, again, unclear in its implications. This ratio is a test of whether the patient uses inappropriate and inaccurate visual cues. Low ratios suggest an abnormal preference of visual inputs.

Since the brain integrates and compares input from all three sensory systems, my guess is that perhaps they are not being weighted equally (given the lower score for the Vestibular ratio), or the vestibular system is perhaps somewhat lessened in the sensory input it provides. (That would raise the question of whether the vestibular system itself is creating inaccurate input, or if that input is accurate but not being properly interpreted by the brain.)

Hi George,
I am very impressed with your tenacity to determine the meaning of the posturography test you had. I think the answers you are looking for you may not find by the results of this one test. This test unfortunately will not give you the specific information you are seeking. If you read Dr. Hain’s full description, it basically says that the test is not very useful and is best used to determine if someone is malingering (this means the patient is faking an illness for secondary gain). This test is not used by most docs unless it is used in the context of a battery of tests because it really doesn’t predict or determine very much. I am sorry you are struggling to get a good deal of meaning from this test, but I really wish you could talk to your doc so he can frame these results in the context of your entire picture. Releasing test results piecemeal to patients only causes more stress and confusion and I really wish you could sit down with your doc with all your results and then come to a conclusion.
I am sorry you have this information without appropriate explanantion by a trained professional.
Hang in there George. You are closer than farther away from getting to the bottom of your suffering.
Best,
Lisa

Hello,
I too failed every single portion of the posturagraphy test therefore I was told I have a balance disorder of unknown origin. It could be MAV or MdDS or something else. This was by a colleague of Dr. Rausch at MEEI. No treatment was indicated.

Sally

All in all, I think this would be more useful a test if I got an ENG or caloric test to go with it. As you [Lisa] have said, it’s not the most useful of tests.

I am sorry you are struggling to get a good deal of meaning from this test, but I really wish you could talk to your doc so he can frame these results in the context of your entire picture.

Yeah, well, I wish I knew for certain whether my doctor WILL be able to glean anything. I’m still not 100% sold on the idea that going to him was the right move, but he has some ideas, so at least we’ll disprove some things along the way.

Releasing test results piecemeal to patients only causes more stress and confusion and I really wish you could sit down with your doc with all your results and then come to a conclusion. I am sorry you have this information without appropriate explanantion by a trained professional.

They gave me all the results; I only uploaded one page. I insisted on a copy. Anyway, I for one am not sorry I got the info first. I want the chance to think about things and try to come to my own conclusions (or at least ideas). A few doctors have given me the “well, I’m the doctor, let ME interpret the results / let me do the figuring-out” line, and quite condescendingly – as though I’m too stupid to have done any relevant research on my own and figure things out.

Hang in there George. You are closer than farther away from getting to the bottom of your suffering.

I think I’m on the express train to Rock Bottom, but unfortunately, I don’t have a round-trip ticket. I see nothing to suggest this has a “bottoming-out” point at which time things can’t go down any farther.