In April 2019, I came down with a nasty case of vertigo. The acute phase lasted a month, and after that it would come and go, never reaching the original peak but also never recovering fully. After a long journey with several specialists, I was seen by an otolaryngologist at Johns Hopkins Medicine, who cured me. Along the way, I learned a surprising amount of fun science. In this blog post, I’ll share a bit about how the episode felt and what I learned.
The main symptom of vertigo is dizziness. This can be fun when you induce it yourself, but it gets old quickly. When dizziness is chronic, it can be very difficult to get work done and to help with childcare. For me, driving was out of the question.
“Thanks, I hate it” is the correct reaction.
Even when the world was not spinning, my head never felt like it was perfectly fixed in space. The sensation is hard to describe, but, imagine that when you try to focus on something in the distance, that thing is always vibrating just a little bit, side-to-side and up-and-down, very quickly. Distant objects felt like they were spread out a little, not perfectly fixed in space. Being perfectly fixed in space is very much a feeling that we take for granted. You only recognize it after you lose it for a while.
The last symptom I felt is much harder to describe - something like the sensation of nails on a chalkboard (but silent), or at times, the feeling or a beam of corrupted data, eminating from the back of my head and toward the left. I haven’t heard others describe anything like this with their vertigo. But for me, it was correlated with times of dizziness, and very uncomfortable. In the early days before the dizziness got strong, there was a feeling of a very soft corkscrew slowly rotating in my skull - this was actually pleasant.
The inner ear
Several players from the anatomy of the inner ear came together to give me my vertigo. The way that they interact is interesting. Consider the hair cell, the cells in the cochlea that are excited by the fluid oscillations caused by sound waves. They have a lot of special adaptations that allow them to meet some difficult constraints - being sensitive enough to detect tiny vibrations, while remaining sensitive and not being torn to pieces by vibrations that are 10 orders of magnitude larger.
These cells’ mix of sensitivity and resilience is wild, and the mechanisms surely were not easy for evolution to come by. Naturally, other uses were found for them.
The same type of cell is used for two sensations that seem completely unrelated to hearing - head orientation and head motion.
To detect rotation of the head, each ear has three ring-shaped tracks, perpendicular to each other. The rings are filled with fluid, which has some inertia. Hair cells embedded in jelly sit at the base of the rings and are stimulated by the speed difference between the ring’s fluid and the ring wall. These rings are called the semicircular canals, and they are large enough to see in an MRI scan. If you’d like to see my semi-circular canals, feast your eyes.
To detect static head orientation, we need to make use of gravity. Imagine you are a Dutchman, you have your buttered toast with heavy chocolate sprinkles1 (above figure, right side). Lean your toast forward and the weight of sprinkles will pull them forward while putting a shearing force on the butter. In the inner ear, instead of sprinkles we have heavy calcium crystals called otoconia. And instead of butter, we have a kind of jelly. Hair cells line the tissue beneath the jelly (the toast in our metaphor) and send setsitive projections through the jelly to detect the sheer force.
Trouble in science paradise
Look back at the Britannica diagram, and notice the area colored pink. This includes both the utricle/saccule with their otoconia, and also the semicircular canals. Although they are separate organs, they are part of the same congiguous fluid-filled area. Part of the cochlea, too, lies in the same fluid bath.
Like any open office plan, this setup has problems. The otoconia crystals sometimes dislodge from their jelly and float into the semicircular canal. A crystal in the canal is not something that the vestibular system can easily cope with. The heavy crystals interfere with the motion of the fluid in the canals during head rotation. And when the head becomes stationary, a crystal under the force of gravity creates a ficticious sense of head movement.
One weird trick…
One of my common complaints about science is that we develop appealing models and simple stories, but they fall over for one reason on another in the face of simple predictions and extrapolations.
Loose crystals from one sensory organ tresspassing into the working end of another sesnory organ is a simple model. What made my vertigo story so delightful to me was the way the model works in practice, to suggest a cure that requires no drugs or prolonged therapy. The treatment is called the Epley Maneuver.
If (a) crystals can get into the semicircular canals, (b) this cause problems when crystals move and interfere with fluid sensors and (c) the shapes of the canals are well known, then perhaps by rotating the head a certain way we could coax the crystals back through the canals and into the utricle where they belong, a bit like the toy with a marble navigated through a maze on a balance board you control with knobs?
Well, for that subset of vertigo cases where loose crystals are the cause, it does work. And one has to wonder, when Epley first tried it successfully, was this a Eureka! moment for him, or with total confidence in the crystal hypothesis did he shrug the maneuver’s success off as trivial.
When the right side (most commonly, the hindmost of the three canals) is the problem, the crystals tend to settle at a low point in the ring, and we want to get them around the top of the ring and back into the utricle. The maneuver goes like this:
- Sit straight up
- Turn the head 45 degrees to the right
- Keeping the turn, lay back fairly quickly, letting the head hang below the sholders
- After the nystagmus subsides, remain lying down and turn the head toward the opposite side
- After the next wave of nystagmus subsides, roll onto your left side, keeping your head turned toward your left shoulder
- After the next wave of nystagmus subsides, lift your body to a sitting position
To see why this works, try the procedure on the model head below. The model has two loose crystals in his right canal. The controls are tricky, but if you get the sequence right, they will land on the green “utricle” and be stable there as long as the head stays upright.
If the head can bec back to the upright position without the red crystals falling back down, you win!
As you can see in the simulation, when the head is still, gravity brings the crystals to their lowest location. A few minutes after lying down in bed, things in the inner ear are settled down. The fluid motion sensors are not being activated. Everything feels back to normal.
Being still in bed is so comfortable, in fact, that you can start to wonder if the whole condition is clearing up and you can go back to normal activities soon. But, for quite some time, sitting up very reliably brings back the vertigo and all the discomfort. This ends up training you not to leave the bed, to spend a long time after waking up in an anxious state, temporarily cured and hoping that you will still be ok when you get up, but knowing that probably won’t happen. It’s emotionally hard, and during this episode, I gained a ton of sympathy for people with chronic illness.
Here is a rough breakdown of the medical care I received, with the cost after insurance.
|2019-06-02||Union Memorial Hospital||$800|
The first two trips happened because the dizziness came on so strongly that my wife and I thought there may be a serious issue. Urgent Care also didn’t want to rule anything out, and they urged us to go to the ER (it was fairly late at night, and I couldn’t reach my family physician).
I was perscribed nausea medicine and told that I probably had viral labrynthitis, which should resolve itself it 3 to 14 days. While the strongest phase did die down after a couple of weeks, I had the residual feelings mentioned above. They could come and go, maybe once a month I had a week of symptoms.
So I kept seeing other specialists. An otolaryngologist at Mercy Medical agreed that it was viral labrynthitis and prescribed low-dose valium and waiting. We decided not to take the valium - due to the wait times before our visits, the visit tended to happen on the tail end of a bout of vertigo, and I was scared of taking anything psychoactive when the symptoms were subsiding anyway.
The trip to Mercy Neurology was recommended because of the stranger symytoms I mentioned above. The nails-on-the-board, the beam of corrupt information - these things hinted that there may be something wrong with my noodle. But the battery of tests didn’t turn up anything, and my MRI scans looked normal.
In summary, the treatment from June through August was kind and caring, but didn’t make much progress in clearing up the symptoms.
As it happens, my wife studied the neurons of the vestibular system2 and the hair cells of the utricle3 in her doctoral and postdoc labs, which were hospital-affiliated. She managed to use some of her connections to get me an appointment at Johns Hopkins Otolaryngology. I’ll add that she did this without much help from me - in a typical partners dynamic, I was resistent to seeing more doctors after having had so little success in the past.
I’m grateful she did, though. Becuase the doctor I saw, Yuri Agarwal, finally diagnosed the issue and solved it during the office visit with the Epley maneuver.
I noticed the impact when I left the office and got into my car. I was between episodes at the time - I thought that I felt mostly fine, not dizzy. In truth, I had adapted to much of the vertigo. And after the treatment, all of the residual symptoms that I had gotten used to disappeared. I felt like I could perfectly focus on distant points. I could move my head around quickly and easily focus on several objects a second (during a dizziness episode, I couldn’t drive; between episodes, I drove rigidly, giving myself lots of extra time before making turns, since it took longer for me to look around at all the surroundings). The general sense of “displacement” was gone. It had been 5 months since I started feeling bad, and now, I felt like I had super-powers. There was a lot of happy giggling on my solo drive home from Hopkins Medical.
Thank you, Dr. Agarwal!
During my visit with Dr. Agarwal, which had the fast pacing of a doctor who leads a dual life as head of a research lab, she explained some of the inner ear biology that kicked off my exploration, and recommended I look up Richard Rabbitt, who has done really interesting physical simulation4 of the Epley maneuver.
There are a lot of inaccuracies in my simulation. To get a much better (though not interactive) view of how and why the Epley Maneuver works. You can also meet Dr. John Epley himself!5
I realize that a lot of this blog post sounds like medical advice. I really want to emphasize - I’m not a doctor. I have no idea how common BPPV is compared to other causes of vertigo, so I have no idea how likely the Epley maneuver is to work for you, if you’re having vertigo.
I wanted to share my story, and to try out some ideas that had gotten into my head (the vertigo simulator and the interactive Epley model above), in the context of this unpleasant episode in my life.
One takeaway - there can be light at the end of the tunnel, and sometimes although a partner’s involvement in your medical choices can feel a little overbearing, they may often be right. As I tearfully told her after my treatment, since I’m naturally reluctant to see doctors, if she hadn’t been so persistent then I might have gone the rest of my life with on-and-off BPPV.