This is Only A Test

So, say you’re me and you’ve been experiencing freakish disturbances in your ability to walk straight or sit still for about two months (which puts us at around mid August 2010.) You’ve done the whole wait-and-see thing and yeah… it’s decidedly not working out. Now what?

Well if you’re healthily insured, you make a trip to see ol’ sawbones, also referred to as your general practitioner (GP.) The GP is like the receptionist of the medical field–they can patch up small little snaffus and hiccups in your well being and it’s good to check-in with the front desk, but for most intents and purposes, they’re going to direct you to the authority properly trained to handle your query. This is affectionately referred to (by myself) as “turfing” and the main goal of the first few weeks is to assess the basic systems and figure out whose turf you belong to. That brings us to the topic of this page.

Testing for Vestibular Problems

When you first wake up with vertigo, it is scary to downright terrifying. You have no vocabulary to properly describe the overwhelming sense of  “AAAAAAGGGGHHHHH!” so you sound a bit caveman-like (or cavewoman-like,) uttering proclamations of “me dizzy. room spinny. feel icky. make stop.” What is the GP to do? Answer: test everything.

This includes musculoskleletal reflexes (the rubber hammer tests) basic neurological screens (similar to your standard sobriety test,) basic psychology queries (of the “it’s all in your head” nature,) visual checks (check out those peepers for abnormalities,) and the pike test.

Pike test? What the heck’s the pike test? You may ask.  Glad youasked–it’s short for the Dix-Hallpike test, and it’s the simplest maneuver to test for benign paroxysmal positional vertigo, or BPPV (aka ear rocks, explained in the Vestibular System! page.) Essentially, the doctor asks you to sit, legs extended on the exam table. Then he (I’m not sexist–I’m just going to use male pronouns here because my doctor’s a guy) rotates your head to either the left or right and helps you lie back quickly. What he’s looking for is a delayed expression of nystagmus, where the eyes twitch back and forth in a characteristic motion. Then he sits you up, and looks for the reverse nystagmus (which is the the same as regular nystagmus, but in the opposite direction of what he just saw.) And then the test is repeated on the other side for comparison. The really cool thing about this test (if it’s positive) is that if the doctor’s good, he can tell from the specific type of pattern your eyes make whether this is vestibular or neurologic, and if it’s vestibular, he can tell you which canal in particular is the troublemaker.

If this test is positive, the patient is often sent for more specific angular testing with a tilt table. The tilt table technician can control the degree of inclination, the speed, and the direction while monitoring vitals of all sorts.

Draconian in its flippy design, the tilt table test is step one-ish in your journey of self-discovery

If this still indicates BPPV, then you’re golden! This type of vestibular problem is quite easily treated once diagnosed and it involves this crazy awesome horizontal dance (no not that horizontal dance) that will guide the particles in your ear causing dizziness back to the corral where they won’t be causing no more trouble now, y’hear? It’s actually a fairly specific exercise, and I’m not fully trained in the choreography, but the image below should give you an idea of  what it looks like.

Synchronized rolling! Like a dance! Like a log-rolling… dancey…dance… ok I tried; it’s just awkward.

Unfortunately we’re not all so lucky as to receive the benign graces of BPPV. In that case, things get more complicated. Since I’ve dedicated an entire blog to dizziness, you’d be safe in assuming that I was not lucky. So now we get into the expensive tests and specialists that make you glad you’ve been paying those insurance premiums.

Neurology

Alright, so extended periods of dizziness and running into walls and falling for no apparent reason isn’t normal. It’s, how do they say… abnormal. This makes medical professionals a bit nervous, like there’s some treachery of magnificent proportions afoot. This is when they bring out the sophisticated imaging technologies–better living through chemistry and physics!

The most oft prescribed doagnostic at this point becomes magnetic resonance imaging, or MRI for those in the know. (For those really in the know, you’ll realize that the MRI is a glorified NMR spectrometer where the magnet spins instead of the sample. Which is the patient. Yeah.. we don’t take too kindly to being rapidly spun at centrifuge speeds–tends to produce.. undesireable results.) The MRI is great for looking at the soft tissue from which your brain is composed. If you’ve got any sort of scarring, tumor, calcification, blood clot, etc, it will show up on the MRI as a dark splotch where there should be no dark splotch.

The basic MRI scan is a 20-40 minute procedure, and it’s absolutely painless. What people take offense to is the coffin-like accommodations of the machine–it’s pretty tight quarters to be sure. But remember, it’s not a vacuum–air is aplenty–and did I mention painless? The only truly annoying bit is that the MRI is a loud sonafabitch when it’s wailing. They call it resonance imaging for a reason–that magnet is singing to the tissues to make them dance just enough to be visible. It’d be romantic, except it sounds like really bad dubstep played on an old-fashioned glitcuy Nintendo during an air raid siren. Not really my jam, but my brain seems to dig it, because my scan came out clean, well-defined, and tumor-free.

But you don’t get off that easy–what the MRI doesn’t see, the CT will.

CT stands for x-ray Computed Axial Tomography, but XCAT is hard to pronounce, so  it’s usually just referred to as a CT scan. Where an MRI uses radio frequencies to image, CT uses x-rays–more ionizaion, more radiation, and more clarity if you want to see heavier elements. That’s why CT scans are usually used for hard things like bone, but sometimes they’ll use it because the methods involved in CT give clearer resoultion (less shadowing) on the image, and with an appropriate contrast material, the CT can outline organs and, more importantly, organ functions much better and more cheaply than MRI.

I underwent fCT of funtional CT, which means I was injected with a contrast material to better see me with, my dear. Turns out… that shit burns with a fierceness. Oh. My god. Not cool. Actually it was cool–too cool, like ice. Like a giant ice dagger shooting through my veins. Consequently, I passed out and the whole thing had to be redone. All in all, though, this scan came back negative for abberations as well.

Just as a reference, the left image would be CT, the right, MRI of the same slice o' brain (not mine.)

Just as a reference, the left image would be CT, the right, MRI of the same slice o’ brain (not mine.)

Both the MRI and the CT prep me for my first specialized visit with the neurologist. When there’s nothing to see here, neurology visits are frankly some of the most boring things out there. Basically none of my symptoms indicated neurologic defect (can I get a freakin’ HALLELUJAH for that!) and it’s time to turf to another specialist.

Optometry

I don’t have much to say about optometry–it’s good to check because a problem with the eyes can cause visual disturbances that can make you dizzy. However, nothing’s wrong with my eyes and we never thought there would be so I don’t really know much about what tests would’ve been done had this been the problem.

Physical Therapy

Another dead(ish) end, vertigo patients are often sent to physical therapy to tease out any problems in locomotion. Basically they do a detailed gait analysis and evaluate your coordination, compensation, and balance skills. From this area, I derived vestibular rehabilitation exercises, but because those become very important later on, I’ve dedicated an entire page to VRT.

ENT/Audiology

And now we’re getting to the good stuff. This is where the real detective work began. At this point, we’ve ruled out brain, muscles, and eyes. In terms of balance problems, that leaves inner ear problems to eliminate.

With ENT, the first visit consisted of looking at the ear with probes and scopes, which can get you to about middle ear no problem. However  all that balance stuff really happens in the inner ear, which makes it much harder to test. Still, there are some things we can do, the first of which is the audiogram. The audiogram is really a sophisticated scheme that uses what we know about how we hear and the materials involved in that hearing to manipulate sound waves in such a way that can objectively measure how well we hear.

The test takes place in a soundproof booth and there are various methodologies out there. The tests I had basically used a series of specialized headsets to measure the sensitivity of each ear, the degree to which sound propagated from one ear to the other though bone, the level of response to a given frequency, and the symmetry of my hearing. 

Audiogram 2010 (top): perfect. Audiogram 2011 (bottom): perfect-er.

My hearing is great according to these exams, which tells the otolaryngologist (ENT doctor) that my cochleae are healthy.

The other part of the inner ear, as you may remember  is the vestibular system which runs on a different set of circuits to some extent. To test the vestibular system, the ENT department has this fancy test called the VNG, or the videonystagmography. 

The test involves donning a set of gloriously heavy goggles equipped with an infrared camera meant to track the motions of your pupils.

Sexy, no? Yeah,it really isn't--I have no idea what she's smiling about.

Sexy, no? Yeah,it really isn’t–I have no idea what she’s smiling about.

In VNG testing, the technician shoots a steady flow of water into your ear–first cold, then warm, then cold. This stimulus will make a perfectly healthy human being dizzy–anybody with a remotely responsive vestibular system will exhibit nystagmus with this test. The key to targeting vestibular damage is the symmetry of the response (meaning the test is done for both ears and then compared.) If the response in one ear is significantly different (stronger, weaker, non-present, etc.) it is usually an indication that there is damage to the vestibular system.

In my case, my right ear was far weaker than my left. This makes sense, because all of the symptoms I feel stem from my right ear. With this last piece of evidence in tow, we ‘re now at a point where a pretty reliable diagnosis is possible.

Diagnosis

At this point, we are in late November of 2010 (about 4 months after I saw my GP.) Based on the lack of response to the Elpey maneuver, my normal response to the neurology screens, my stable walking gate, my clean brain scans, and my perfect audiogram(s) the only real evidence that there is a significant problem is in the VNG coupled with my past history of viral infection. However, that is really enough for a diagnosis of vestibular neuritis–in fact, vestibular neuritis is by nature a diagnosis of systematic elimination since there is no test as of today that specifically tests for it. 

My dizziness symptoms began a few months after I recovered form a particularly nasty upper respiratory infecti0n. The duration of that illness (3-4 weeks of bronchitis-level convalescence) was sufficient for the virus to migrate to my inner ear and set up camp. While there, it inflamed and ultimately damaged my vestibular nerve, leaving the cochlear nerve in tact. Thus I can hear, but my balance is screwed over. This is why the VNG showed asymmetric behavior. Unfortunately, because of the duration of the vertigo, the condition is now classified as permanent–I will always have some degree of dizziness.

That isn’t to say that I can’t augment the level of dizziness I experience! To that end, refer to the next three pages: I want a new drug (where I discuss ingestible and homeopathic treatments ) VRT (where I come back to vestibular rehabilitation therapy with dedication,) and DBT (where I do my best to discuss the basics of dialectic behavioral therapy with regards to vertigo.)

Back to the Deets!

Back to the Posts!

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