Ep. 224: Vertigo, Dizziness and Traumatic Brain Injury

00:00:00: Welcome to ENcast, your weekly source for education research and updates from the European Academy of Neurology.

00:00:16: Hello!

00:00:17: And welcome to EN cast neurology.

00:00:20: this month's topic is neurotraumatology.

00:00:32: My name is Marius Siemenski and I am a specialist in neurology, and an emergency medicine.

00:00:39: And i'm working as the head of emergency department at Medical University of Gdańsk in Poland.

00:00:45: And had great honor to have my guest here today which is Barry Simongal from London UK specialist in Neurology with special interest and huge experience in disorders of balance, dizziness and vertigo.

00:01:05: Barry works at Imperial College London.

00:01:11: Hello

00:01:11: Barry!

00:01:12: It's great to have you here.

00:01:15: I'm extremely happy that we accepted the invitation for this podcast recording because it is a huge epidemiological problem but unfortunately quite often neglected in the curricula of neurology, which is Neurotraumatology and on a specific part off this area.

00:01:39: Which is traumatic brain injury related vertigo dizziness or problems in control of balance.

00:01:47: TBI is problem for many patients.

00:01:54: The first question is with such a numerous population of patients, whether we shall consider them as one group or should we divide the patient into some subclasses of risk for developing vertigo or dizziness in relation to DBI.

00:02:13: Shall we talk about low-risk patients and high-risk people?

00:02:18: How do you feel?

00:02:20: First of all Marius it's my pleasure speaking today.

00:02:24: It was great to meet recently online, and then previous to that it was great.

00:02:28: To meet up in the previous year meeting early this summer.

00:02:34: so yes balance problems are very common following a traumatic brain injury And The approach of the patient depends on several factors.

00:02:48: and you hinted On different patients may respond in different ways, given the same head injury.

00:02:58: And so if we split up the types of brain injury let's say into severity or brain injury and also to that particular cause Let us talk about mild traumatic brain injury for a start.

00:03:13: Mild Traumatic Brain Injury obviously covers quite very wide gamut on severities.

00:03:20: So from patient who may have lost consciousness momentarily for seconds to someone was being confused.

00:03:32: Following the head injury four baby twenty hours which is quite a big difference from the patient recovers within a minute or two.

00:03:40: and so you already had this difficulty with in the category mild traumatic brain injury of large differences in force applied ahead, If we talk about, let's say sports setting which I think is a separate setting from the non-sports setting.

00:04:00: And I think sportsmen in contact sports for example rugby players or American football players they have repetitive head impacts and many of these impacts do not result in an obvious brain dysfunction.

00:04:20: but the emerging data suggests that each of these impacts which are significant can produce some small level.

00:04:30: Let's say brain injury, which may not manifest acutely but accumulates over time.

00:04:37: and on top that slow accumulation you have this more significant impact with the particular sports person me then present to their doctors, for example with a significant impact leading to loss of consciousness.

00:04:56: For ten or fifteen seconds often with posturing this particular impact.

00:05:03: recent research shows that the midbrain is particularly vulnerable and mid brain structures are important for balance control as well control or the modulation of consciousness.

00:05:20: So you have obviously patients losing consciousness and following this impact is standard protocol to assess balance empirically, This has been observed to be an important feature of sports mild traumatic brain injury until good reason because of being involvement with midbrain which affects a balanced in that acute setting.

00:05:45: On top of what I alluded to earlier on, this repetitive injury which causes a more diffuse.

00:05:51: Injury and damage in dysfunction which accumulates over time Which we think potentially increases the risk of neurodegeneration after several decades.

00:06:03: However as doctors will have to remind patients that there are many factors That lead to neuro degeneration not just brain injury But lifestyle factors like inactivity, obesity diabetes hypertension smoking etc.

00:06:20: And so sports people are not immune to all of these factors that promote dementia.

00:06:28: That affects us all.

00:06:30: So quite separate from the issue Of sporting injury No regeneration and balance our lifestyle factors sports people should continue in the decades after the end of their professional or high-level career.

00:06:49: But coming back to the balance issue, if we split up this sporting injury into two components... The acute imbalance is something that has been observed and it definitely involves brain stem structures.

00:07:10: But also in the long term, we know that neurogenerative disease is linked to imbalance.

00:07:17: And we can talk a little bit later about that.

00:07:20: and apart from subcortical structures at an important balance control In The Human with unique bipedal upright stance which develops late actually relatively late, let's say.

00:07:39: Because it takes a human similar period of time to acquire good postural control over the same period that you acquire language.

00:07:48: and is interesting too.

00:07:50: consider the fact as we evolved from quadrupeds to bipeds this was when the human brain developed quite significantly in tandem with prehensile control.

00:08:04: so you know that there is a very intimate link necessary in humans between cognition and balance.

00:08:12: And, in fact, imbalance control we've shown in moderate to severe brain injury patients.

00:08:17: it's critically dependent on biohemispheric connectivity so this can be affected both acutely but one would also predict that patients with subacute chronic development of brain conditions would also have bound problems.

00:08:42: And then just the last thing to say, because we focus on mild traumatic brain injury and we can talk about other components later on or the severities.

00:08:52: but the balance control mechanism is an early warning system for brain dysfunction Because it's so precarious because it's easy to fall standing on two feet.

00:09:07: I mean, I say the patients When was the last time you saw a two-legged chair?

00:09:14: They do exist but with special structures But its very precarous and balance is something that we should pay more attention too And can talk about that component later About the link between imbalance And the subjective complaint of Vertigo.

00:09:34: Yes, I think in your response some elements appear which relate to my next question because from my experience as a neurologist and an emergency physician i know that in civilian settings most patients coming to emergency department with head injury mild traumatic brain injuries frequently are elderly patients, usually with some neurodegenerative problems or vascular problems who already suffer from chronic dizziness or impaired balance control.

00:10:14: And this chronic problem is the cause of falls at home and then experiencing a head trauma.

00:10:23: do you think that we have any area for prevention?

00:10:28: in that population, leading to diminishing the incidence of head injuries in those populations.

00:10:37: Marius said an excellent and important question because what we are talking about is modifiable risk factors for falls... ...and therefore modifiable risks factors for mobility and mortality.

00:10:51: There was a paper published in JAMA neurology i believe in twenty twenty four isla et al.

00:10:59: i could be corrected.

00:11:02: if i remember correctly this was a thirty year prospective study with fifteen thousand participants and they separated patients into mild traumatic brain injury moderate to severe traumatic brain injuries, any control group at the end of the fifteen years fifty percent off control group.

00:11:25: Had died because we all have an expiry date and there was a significant but important difference in mortality for mild traumatic brain injury patients, they still had the higher mortality rate than controls.

00:11:42: Increased again for moderate to severe traumatic brain injuries.

00:11:45: that's supposed no surprise.

00:11:48: however what is important?

00:11:52: they looked at the causes of excess mortality between the three groups and that included things like endocrine causes, cardiovascular causes cancer causes.

00:12:06: Then there were two features that stood out that predicted mortality And one was neurodegeneration.

00:12:15: So no surprise that a traumatic brain injury if fifteen years before let's say on average increase the probability of mortality over that period and that was an ink again more obvious in a mother to spend on the mild, but the other thing was recurrent trauma.

00:12:34: so if you have one trauma.

00:12:37: You increased the risk of further trauma.

00:12:41: and what is the modifiable risks?

00:12:44: Of trauma are preventable balance disorders.

00:12:49: so whilst at the moment We do not have direct intervention for no generation as we previously described and discussed.

00:12:59: There are modifiable risk factors like style, diet, hypertension and so forth.

00:13:05: keeping your friends and making sure that you're a cognitive reactive person being happy is important but in terms of balance this is critical.

00:13:18: Let's go back specifically to your question.

00:13:21: What can we do about this?

00:13:24: So first of all, one very common feature consequence of a traumatic brain injury is an inner ear problem called benign paroxysmal positional vertigo and this is treatable.

00:13:41: in fact it's curable.

00:13:47: In fact, the prevalence of BPPV is the acronym increases with the severity.

00:13:54: Of the head injury.

00:13:56: so the more severe your traumatic brain injury that more likely you are to have BPPV in fact be patients without a mild mild traumatic brain injuries With imbalance I certainly much more likely to have brain injury then ear problems, because the ear mechanism is quite robust.

00:14:21: And in some regards I believe based on data we've got that the brain is more vulnerable to an injury first and here second.

00:14:34: so when you go obvious ear manifestations of a of an injury it suggests at the force has been quiet significant.

00:14:46: However, coming back to the treatable feature of BPPV.

00:14:50: This is a diagnosable by a Dix-hole pipe manoeuvre which will produce illicit anesthagmas and it can identify that particular canal in two canals at the commonly affected other posterior canal And they horizontal canal and each have their specific maneuvers for treating and curing.

00:15:14: The last thing to say about The vulnerable group in terms of acute treatment is that they may not complain about vertigo.

00:15:23: Now, we demonstrated this phenomenon which we call vestibular agnosia and it's a higher order vestibulocognitive syndrome which is linked to brain disconnection.

00:15:35: so infact turns out there isn't one brain region that mediates vertical perception is dependent on brain networks and that network involves by hemispheric connectivity apart in addition to some cortical circuit, quite a diffuse mechanism.

00:15:56: Now following brain injury in healthy young adults if the more surveyed the brain injuries are less likely our patients to complain of vertigo dpv and we publish some initial results over the last five years about these data.

00:16:16: so that way to diagnose bppb following a head injury in healthy adults who may not complain of vertigo.

00:16:24: It's too examine them.

00:16:26: now.

00:16:27: talking on the elderly patients from recent data shows that i am in a group of two hundred community dwelling healthy elderly subjects over age.

00:16:37: sixty-five, of these individuals have another tundered vestibular perception.

00:16:44: when measured objectively in the laboratory.

00:16:47: So if an individual in that twenty percent has a fall and had BPPV, they already are unlikely to complain or traditional vertical symptoms let alone somebody who has a significant brain injury then there also not going to complain about.

00:17:07: it goes so at point being.

00:17:09: Some of the elderly patients may fall with or without a head injury due to BPV.

00:17:17: Without vertigo and this is a problem because it's the latest world falls.

00:17:23: guidelines finally and got to find me in talk about vertigo, and then need to screen for BPV in patience with symptoms on vertigo.

00:17:37: however our call is a bit more than that.

00:17:40: since at least a quarter of healthy community-dwelling elderly patients do have an impaired vestibule perception, then patients can have BPPV in the community with falls and nowhere to go.

00:17:55: So really that guidelines are missing for potential patient who has fall from BPV.

00:18:03: so what we would say is to screen these patients irrespective our head injury or not everybody who has a fall when I see them, be they eighteen or eighty-eight.

00:18:17: I perform position maneuver looking for positional nystagmus and we can talk about that in the next question.

00:18:27: but for me positional Nystagmus provides lots of information.

00:18:32: Okay so definitely have large area potential preventive interventions based on proper diagnosis of, well BPV without clinically overt vertigo.

00:18:46: Now coming from prevention chronic conditions to acute situation let's imagine situations which is quite frequent in emergency department a patient who experienced head injury or even mild traumatic brain injuries and Clinically seems to be neurologically intact without any neurological deficit, meanwhile claiming to suffer from let's say subjective feeling of dizziness or vertigo.

00:19:16: patients may call it.

00:19:18: Do you believe that all patients with such complaints require neuroimaging CT scan?

00:19:25: Or maybe just clinical testing but will good enough solve any diagnostic issues in?

00:19:33: Okay, another great question and important question because it's a common scenario in the emergency room.

00:19:40: So assuming that patient has not had any alcohol Because with alcohol you will have abnormal examination findings And then difficult to interpret what you found.

00:19:53: but in the patient who is not intoxicated I think there's value.

00:19:57: first of all looking at balance.

00:19:59: so sports people professionals understood that balance is very susceptible to mild traumatic brain injury.

00:20:08: That's why the SCAT test has a balanced assessment as being really core part of your assessment, and I think this probably relates at least in the sporting situation or mid-brain structures.

00:20:30: so tandem standing, which is actually challenging for many elderly patients.

00:20:38: But in a young subject they should be able to do twenty seconds of tandem standing without any difficulty.

00:20:45: Tandem walking and I objectify the tandem walking just like an objectified tandem standing requires twenty second.

00:20:53: I'll do ten steps and in healthy young person there no mistakes make a mistake.

00:21:00: i get them to repeat it and i really am only satisfied when they do ten out of ten tandem steps without ever.

00:21:07: I also do the rhomburg.

00:21:08: actually you know in there in a traumatic, mild minded brain injury would not expect the rhomber be abnormal.

00:21:15: if that were it may suggest is some other predisposing problem for the fall.

00:21:20: then i will assess my movements with patient sitting on side The trolley in the emergency room and then a healthy young individual.

00:21:30: This is quite an easy task because you would expect normal gays, normal smooth pursuit, normal circuits.

00:21:39: um And if you found any abnormality than that would be significant.

00:21:43: obviously In L-vitations seventy five and over You will have abnormalities such as abnormal smooth pursuit occasional mild secadic dysmetry and i didn't mention but convergence insufficiency is almost ubiquitous above the age of seventeen.

00:22:02: so it doesn't have much doesn't come very much information.

00:22:05: Obviously a young person who can converge assuming they are always had three divisions.

00:22:13: to good question ask you know when u go to cinema any put those special glasses on dc three v?

00:22:19: if, They don't, it means they've had a problem with binocular vision for a long time.

00:22:23: And this is not new funding.

00:22:25: but normally if you can't converge and there are twenty five that's the problem.

00:22:30: so those all of these features for me indicate some central problems.

00:22:34: I mean lastly But at least i do position testing and position testing from me as useful now appreciate clinicians who are not accustomed to doing a Dixhole pike or central head position test.

00:22:50: Any may not be comfortable, particularly with respect to concern of neck injuries.

00:22:55: and I agree this should only be done by individuals who were comfortable an expert in the assessment.

00:23:02: but as an expert i don't have much concerned because they do not move their necks into position tests.

00:23:08: it's head-in space And that even done this position test with a subject in the wheelchair without moving their neck.

00:23:16: so it is possible but you obviously need significant experience now.

00:23:21: why do i do this?

00:23:22: first of all as we mentioned already.

00:23:25: If there's bpv present in a patient head injury.

00:23:29: my interpretation is either this cause default and if isn't treated at risk or more falls, So when you send them home, they will have another fall.

00:23:40: Another fall... They might come back this time with a more severe head injury because BPPV which is untreated definitely causes falls and the data show treating BPPP reduces faults.

00:23:52: then that second thing is if there was no suggestion of BPPB before the fall particularly for their young person saying I never had vertigo before Then it implies to me force of the head injury was significant.

00:24:09: because we've published in a hundred and fifty, albeit hospitalized TBI patients that the rate of BPV with a skull fracture is sixty-six percent.

00:24:19: And brain entry without the skull fracture it's thirty three percent.

00:24:24: so there are fours dependent factor there.

00:24:27: So if some suggestion that BPD occurs In more severe head injuries?

00:24:33: So I would consider this patient may need a brain scan because it's suggesting that there maybe at least the skull fracture, given the connection between BPP and skull fracture.

00:24:44: And potentially an underlying brain injury.

00:24:47: then The last thing is positional nystagmus might be central.

00:24:51: not all positions nystagmuses BPPV.

00:24:54: now when I see a central position of stagmas in the immodestinal setting It is often related to alcohol probably most commonly.

00:25:06: So assuming there's no alcohol and no other cause of intoxication, then this is telling me that it has a central cerebellar dysfunction.

00:25:14: It means either the patient had pre-existing cerebellary dysfunction or they've had TDI with disruption of cerebellum mechanisms like a cerebellic contusion... Or occasionally we see head injury was incidental and they have had dissection vertebral artery dissection, with an embolic stroke causing a cerebellar infarct and therefore causing imbalance in business.

00:25:44: And clearly neuroimaging is required.

00:25:46: that case I would say for head injury severe cerebellary syndrome over brain stem signs are red flag without intoxication.

00:25:59: this is telling me either.

00:26:00: as patient has pre-existing cerebellum syndrome All they may certainly have had a stroke and that was manifesting as a fall on the TBI, I've seen more than one case like this.

00:26:13: And so...I do look for these signs.

00:26:17: In that case obviously if it's hypercutone set get a CT because you're looking for hemorrhage to begin with.

00:26:23: but even though the CT is negative in acute Stroke presenting an acute vestibular syndrome up Twenty percent of hypercute MRI scans can be negative, falsely negative.

00:26:39: So certainly the clinical assessment for me is critically important.

00:26:45: so maybe I've extolled a bit too much there on let's say less usual cases that have seen over-the years cases very much like that including stroke masquerading as a head injury and requiring the patient to be transferred from the major trauma ward A hypercute stroking.

00:27:04: Thank you very much, Barry.

00:27:05: the area we challenged to cover in this podcast is extremely large TBI as such and balance disorders that take home a message one it's extremely clear from your talk but nothing more important than precise clinical examination based upon good understanding of anatomy especially posture control and that is something essential in everyday neurological practice.

00:27:36: so first we must.

00:27:39: Precisely examine our patients when connected to the anatomy.

00:27:44: on that way one side we may discover the patient's requiring a prophylaxis due two very chronic problems with posture control or in acute settings you do that, we may identify the patients requiring escalation in terms of neuroimaging.

00:28:04: Thank you very much for this talk, once again I had an honor to talk with Barry Simmengel from Imperial College in London.

00:28:12: thank you all listeners and please take care your vertigo and injured patient.

00:28:18: Thank You Very Much!

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