27:37 Eli: Alright Miles, so we've covered BPPV pretty thoroughly, but what about when the Dix-Hallpike is negative and I'm still convinced the patient has vertigo? I feel like those are the cases where I sometimes get stuck.
27:49 Miles: Oh, those are some of the most interesting cases! And honestly, they're where a systematic approach really pays off. Let's talk about Ménière's disease first because it's probably the second most common peripheral cause you'll see.
16:14 Eli: Yes! I feel like I diagnose Ménière's less confidently than BPPV. The triad is vertigo, hearing loss, and tinnitus, but how do I know when those symptoms really add up to Ménière's?
28:12 Miles: The key is understanding the specific pattern. Ménière's episodes typically last 20 minutes to 12 hours—that's much longer than BPPV but shorter than vestibular neuritis. The hearing loss is characteristically low-frequency and fluctuating, especially early in the disease.
28:29 Eli: What do you mean by fluctuating?
28:31 Miles: Patients will notice their hearing gets worse during episodes and then improves between episodes, at least initially. Over time, the hearing loss tends to become more permanent. And the tinnitus often has a specific quality—patients describe it as roaring or like the ocean, not the high-pitched ringing you might hear with other causes.
28:52 Eli: And the aural fullness—that feeling like the ear is plugged?
3:23 Miles: Exactly! That sensation of pressure or fullness in the affected ear is really characteristic. Patients often describe it like being underwater or having their ear blocked. It's thought to be related to the increased endolymphatic pressure that's central to Ménière's pathophysiology.
29:11 Eli: So if I have someone with episodic vertigo lasting hours, low-frequency hearing loss, tinnitus, and ear fullness, that's pretty classic for Ménière's?
29:21 Miles: That's the classic presentation, but here's the thing—you need to document the hearing loss with formal audiometry to make a definitive diagnosis. The diagnostic criteria require objective evidence of sensorineural hearing loss on at least one occasion.
29:36 Eli: Right, so I should be referring these patients for audiology evaluation. What about treatment for Ménière's? I know it's more complex than just doing a repositioning maneuver.
29:44 Miles: Ménière's treatment is definitely more involved. The acute episodes can be treated symptomatically with antiemetics and vestibular suppressants, but the long-term management focuses on reducing the frequency and severity of episodes.
29:57 Eli: And that's where dietary modifications come in, right? I've heard about low-sodium diets.
30:02 Miles: Yes, though the evidence is actually pretty limited. The traditional recommendation is to limit sodium to less than 2 grams per day, based on the theory that reducing sodium might decrease endolymphatic fluid retention. But recent studies suggest the benefit might not be as clear as we once thought.
27:01 Eli: Interesting! What about diuretics? I've seen patients on hydrochlorothiazide for Ménière's.
30:25 Miles: Diuretics are commonly used, again based on the fluid retention theory, but the evidence is mixed. Some patients do seem to benefit, but it's not universal. The challenge with Ménière's is that it's a very heterogeneous condition—what works for one patient might not work for another.
30:40 Eli: That sounds frustrating for both patients and doctors! Now, let me ask about vestibular neuritis because that's another one I see but feel less confident about.
30:50 Miles: Vestibular neuritis is actually pretty distinctive once you know what to look for. It's typically a single episode of severe, continuous vertigo that lasts days to weeks. Patients are often completely incapacitated initially—they can't get out of bed because the vertigo is so severe.
31:06 Eli: And hearing is typically normal, right? That's how you distinguish it from labyrinthitis?
3:23 Miles: Exactly! Vestibular neuritis affects only the vestibular nerve, so hearing is preserved. If someone has the same clinical picture but with hearing loss, that's labyrinthitis—inflammation of both the vestibular and cochlear portions of the eighth cranial nerve.
31:26 Eli: And these patients often have a viral prodrome?
31:29 Miles: Often, yes. Many patients report having had a cold or flu-like illness in the weeks before the vertigo started. The theory is that viral inflammation affects the vestibular nerve, similar to how Bell's palsy affects the facial nerve.
31:42 Eli: How do I examine these patients? They're often too dizzy to do much testing.
31:47 Miles: That's where the HINTS exam we discussed earlier becomes crucial. These patients should have an abnormal head impulse test on the affected side—you'll see those catch-up saccades. The nystagmus should be horizontal with a torsional component, beating away from the affected side.
32:01 Eli: And it should be unidirectional and not change with gaze direction?
15:59 Miles: Right! That's key for distinguishing it from central causes. The nystagmus might be suppressed somewhat by visual fixation, which is another sign that it's peripheral rather than central.
32:14 Eli: What about treatment for vestibular neuritis?
32:17 Miles: The acute phase can be treated with vestibular suppressants—meclizine, diazepam, or antiemetics—but only for a few days. The key is early mobilization and vestibular rehabilitation exercises to promote central compensation.
32:30 Eli: I've heard about steroids for vestibular neuritis. Is that evidence-based?
32:35 Miles: The evidence is mixed. Some studies suggest that early corticosteroids might improve long-term outcomes, but the benefit isn't dramatic. If you're going to use steroids, they need to be started within the first few days, similar to Bell's palsy treatment.
32:50 Eli: Now, let me ask about vestibular migraine because that seems like it might be underdiagnosed. How do I recognize it?
32:57 Miles: Vestibular migraine is probably much more common than we used to think. The key is recognizing that the vertigo and the headache don't have to occur simultaneously. Patients might have episodes of vertigo that are temporally related to their migraine pattern, even if they don't have a headache during every vertigo episode.
33:15 Eli: So someone could have vertigo on Monday and a migraine on Wednesday, and that could still be vestibular migraine?
3:23 Miles: Exactly! The diagnostic criteria require at least five episodes of vestibular symptoms lasting 5 minutes to 72 hours, with migraine features during at least 50% of the episodes. But those migraine features could be headache, photophobia, phonophobia, or visual aura.
33:38 Eli: And presumably, these patients should have a history of migraines?
33:41 Miles: Yes, either current or past history of migraine. That's why taking a really detailed headache history is so important in anyone with unexplained vertigo episodes.
33:50 Eli: What about treatment for vestibular migraine?
33:53 Miles: It's similar to regular migraine treatment—identifying and avoiding triggers, acute treatment with triptans or NSAIDs if appropriate, and preventive medications for frequent episodes. The preventive medications are the same ones used for regular migraines—topiramate, propranolol, amitriptyline.
34:11 Miles: You know, one thing that ties all these conditions together is the importance of patient education. Whether it's BPPV, Ménière's, vestibular neuritis, or vestibular migraine, patients need to understand their condition, what to expect, and when to seek further care.