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*Only for medical professionals to read for reference attack time, attack frequency, nystagmus.
.
.
These points must be known! In the previous article, we introduced 3 cases of misdiagnosis and mistreatment (is positional vertigo necessarily "otolithiasis"? Click to view), and used data to show otolithiasis (BPPV) and vestibular The worrisome misdiagnosis and mistreatment of migraine (VM), initially clarifying the diversification of the clinical manifestations of VM is the key to the differential diagnosis
.
So, this article will show in-depth how to make a differential diagnosis of BPPV and VM, and what are the main points
.
Be familiar with the attack time and frequency of BPPV and VM.
In the overview of ICVD issued by the Barany Association, BPPV and VM belong to episodic vestibular syndrome (EVS)
.
EVS is defined as a group of syndromes characterized by brief episodes of vertigo/dizziness and unsteadiness
.
It is characterized by provoked or spontaneous repeated attacks lasting from seconds to hours and occasionally days
.
Both VM and BPPV belong to EVS, indicating that their clinical features have some commonalities, and they are easy to be misdiagnosed in an atypical state, which requires careful screening
.
Identification points: onset time
.
The duration of BPPV attacks is calculated in seconds and minutes; while VMs vary widely, generally ranging from 5 minutes to 72 hours, of which about 30% last for a few minutes, about 30% last for a few hours, about 30% last for a few days, and the remaining 10%.
% only lasts a few seconds
.
frequency of seizures
.
Some studies have shown that the frequency of VM vertigo attacks is significantly higher than that of BPPV.
The former is measured in days, and the latter is measured in weeks.
VM attacks are more frequent, especially in the case of repeated recurrence of suspected BPPV, which requires repeated reduction treatment, and even a single attack can be achieved by repeated reduction.
Patients with suboptimal response to treatment should consider excluding VM
.
Mastering the nystagmus characteristics of BPPV and VM Nystagmus is an important sign of vestibular disease and a key indicator for differential diagnosis of related diseases
.
Published online on June 14, 2019 in the Vestibular Research (J Ves Res) electronic edition, the Barani Society Classification Committee of Vestibular Disorders defines nystagmus as an involuntary, rapid rhythmic oscillating eye movement with at least 1 Slow phase
.
Nystagmus is divided into physiological nystagmus and pathological nystagmus, the latter including spontaneous nystagmus, gaze-evoked nystagmus, and triggered nystagmus
.
Triggered nystagmus includes benign paroxysmal positional nystagmus (BPPN) and central positional nystagmus (CPN)
.
BPPN is a specific nystagmus related to a specific semicircular canal plane induced by head movement to a new position.
It has the characteristics of short onset time, latency, fatigue, and angular acceleration movement correlation.
It is a peripheral vestibular disease nystagmus
.
The nystagmus of VM is CPN, which is characterized by diversity, variability, and not characterized by fixed semicircular canals.
It is a central vestibular disease nystagmus
.
The detection of nystagmus with different characteristics is an important basis for differentiating BPPV and VM, but nystagmus examination in clinical work will be limited by the examiner's experience and equipment, so correct clinical diagnosis ideas are needed in order to reduce deviations
.
Professor Jiang Zidong emphasized: "The judgment of BPPN must conform to the description of its diagnostic criteria", and also listed the detailed clinical diagnosis ideas for us: (1) BPPN has false negatives during the induction process, and the patient's head is placed on the patient's head at the beginning of the induction test.
It is in a vertical position parallel to the gravity line of the semicircular canal to be tested.
During the inspection, keep the head in the plane of the semicircular canal to be tested.
Only then can the maximum intensity of BPPN be recorded, which is helpful to identify the laterality of the BPPV and the semicircular canal responsible
.
(2) In the posterior semicircular canal BPPV position induction test, the patient had torsional nystagmus in the suspended head position, and the direction of the nystagmus was reversed when returning to the sitting position, that is, torsional nystagmus.
If the nystagmus does not reverse, it may be VM
.
(3) Spontaneous nystagmus does not occur in BPPV, and BPPV may produce nystagmus in the median gaze position during direct vision, which is called pseudo-spontaneous nystagmus
.
Tilt the head forward 30° and the nystagmus disappears.
When the head is tilted further forward, the direction of the nystagmus is reversed, which is essentially another form of triggered nystagmus
.
(4) In the horizontal semicircular canal BPPV position induction test, the patient presented with horizontal direction changing positional nystamus (DCPN).
The strength of the nystagmus assists in judging the side of the responsible semicircular canal and the direction of the nystagmus.
Determine whether a tube stone or a curled cap stone
.
If non-DCPN occurs during the diagnosis and treatment of BPPV, or the nystagmus changes from geotropism to epicenter, it may be related to otolith ectopic, and it may also indicate VM or light capping
.
(5) Anterior semicircular canal and multisemicircular canal BPPV are rare, especially in the face of poor effect of repeated reduction, inducing vertical nystagmus, and being diagnosed as refractory BPPV patients, it is necessary to exclude central diseases including VM, vestibular paroxysms, congenital Skull base malformations and fourth ventricle tumors
.
Other skills and key points The treatment of VM includes patient management and drug therapy, and the rational selection of therapeutic drugs is the key to the treatment and prevention of recurrent dizziness/vertigo in VM
.
Otolith repositioning therapy is ineffective for positional vertigo and nystagmus in patients with VM.
When it is clinically highly suspected that BPPV is ineffective for repeated treatment, or patients with repeated recurrence, careful evaluation is required to exclude VM
.
At the same time, in the process of BPPV diagnosis and treatment, standardized diagnosis and treatment is very important
.
In the 2015 version of the BPPV diagnostic criteria and the 2017 version of the BPPV clinical practice guidelines, there was no breakthrough in the understanding of the pathogenesis of BPPV, and the otolith theory (including the theory of canal and cap stones) is still a generally accepted theory.
The dislodged otolith falls into the semicircular canal or adheres to the cap of the ampulla ridge of the semicircular canal.
When the head moves in the plane of the involved semicircular canal, the otolith's gravitational direction changes and stimulates the vestibular terminal receptors, and the excitatory vestibular signal goes from the outer circumference to the outer circumference Central transmission, causing dizziness/vertigo and nystagmus
.
The presence of symptoms of dizziness/vertigo and the presence of nystagmus specific to the involved semicircular canals in a position-specific provocation test (Dix-hallpike or head roll test) are critical for the diagnosis of BPPV
.
The main points of BPPV treatment include: (1) During the repositioning process of BPPV, keeping the head rotating in the plane of the semicircular canal to be tested not only induces positional nystagmus of maximum intensity, but also is the key to the success of manual repositioning
.
(2) The treatment of BPPV needs to be standardized, that is, for typical BPPV, once the diagnosis is clear, manual reduction treatment can be performed in time, and pure tone audiometry, vestibular function, and inner ear and cranial imaging examinations are not considered for the time being
.
(3) The patient's original positional vertigo/dizziness and nystagmus disappeared after manual reduction treatment, which supports the diagnosis of BPPV
.
8 points for clinical practice according to the diagnosis and treatment guidelines 1.
During the diagnosis and treatment of BPPV, the concepts of atypical BPPV and subjective benign paroxysmal positional vertigo (SBPPV) that have appeared in the past are easily confused with VM
.
2.
Tirelli et al.
conducted a controlled study on dizziness patients without nystagmus and dizziness patients with typical nystagmus, and found that there is atypical BPPV, and its treatment is not significantly different from typical BPPV
.
3.
Haynes et al.
proposed the concept of subjective BPPV.
They called patients with typical symptoms, negative BPPN, but good effect of manual reduction as SBPPV; patients with typical symptoms, positive BPPN, and good effect of manual reduction were called objective BPPV ( objective benign paroxysmal positional vertigo, OBPPV)
.
4.
In the 2015 new version of BPPV diagnostic criteria, SBPPV with onset time less than 1 min and exclusion of other vestibular diseases was defined as spontaneous remission and possible BPPV
.
5.
The pathogenesis of BPPV is the otolith theory.
The current inspection methods cannot directly show how the otolith fall off and cause vertigo and nystagmus, and how the manipulation of the otolith can restore the otolith and cause the vertigo and nystagmus to disappear.
According to the position test The characteristics and direction of the induced nystagmus in the semicircular canal to determine the responsibility of the otolith fall off, so as to choose the correct reset method
.
Nystagmus is an objective basis for diagnosis and treatment, but the only objective indicator of BPPV subtypes with spontaneous remission and possible BPPV is missing, which easily affects the judgment of doctors, and clinical diagnosis and treatment are risky and challenging
.
In the annotations and comments of the 2015 version of the BPPV standard, the identification of this type of BPPV and VM is particularly emphasized to avoid misdiagnosis and mistreatment
.
6.
The frequency of dizziness/vertigo episodes is different between BPPV and VM patients.
The former is measured in weeks and the latter is in days.
VM attacks are more frequent, and BPPV with repeated otolith repositioning and treatment, or BPPV with poor repeated treatment effect needs to be treated.
Exclude VMs
.
7.
In the face of refractory BPPV, it is necessary to exclude VM before surgery, especially in patients with refractory BPPV who are going to undergo surgical treatment
.
Leveque et al.
found that the number of cases of refractory BPPV treated by surgery decreased significantly after 1990, because in the late 1980s, the existence of horizontal semicircular canal and superior semicircular canal BPPV was recognized, and their clinical characteristics were different from those of posterior semicircular canal BPPV.
And effective manual reduction method, so that those patients who were misdiagnosed as posterior semicircular canal BPPV due to the limited level of diagnosis and treatment are not difficult to treat
.
8.
Reflections and lessons from the clinical practice of BPPV are: for self-limiting diseases, especially for benign diseases, when the treatment plan may potentially harm the patient, sometimes it is worth waiting and observing, avoiding excessive surgical treatment or destructive treatment
.
This article is compiled from the wonderful lecture given by Professor Jiang Zidong of Peking Union Medical College Hospital at the 2021 Cerebrovascular Disease Beijing Forum - "Discussing Otolithiasis Repositioning Skills and Discrimination of Vestibular Migraine"
.
.
.
These points must be known! In the previous article, we introduced 3 cases of misdiagnosis and mistreatment (is positional vertigo necessarily "otolithiasis"? Click to view), and used data to show otolithiasis (BPPV) and vestibular The worrisome misdiagnosis and mistreatment of migraine (VM), initially clarifying the diversification of the clinical manifestations of VM is the key to the differential diagnosis
.
So, this article will show in-depth how to make a differential diagnosis of BPPV and VM, and what are the main points
.
Be familiar with the attack time and frequency of BPPV and VM.
In the overview of ICVD issued by the Barany Association, BPPV and VM belong to episodic vestibular syndrome (EVS)
.
EVS is defined as a group of syndromes characterized by brief episodes of vertigo/dizziness and unsteadiness
.
It is characterized by provoked or spontaneous repeated attacks lasting from seconds to hours and occasionally days
.
Both VM and BPPV belong to EVS, indicating that their clinical features have some commonalities, and they are easy to be misdiagnosed in an atypical state, which requires careful screening
.
Identification points: onset time
.
The duration of BPPV attacks is calculated in seconds and minutes; while VMs vary widely, generally ranging from 5 minutes to 72 hours, of which about 30% last for a few minutes, about 30% last for a few hours, about 30% last for a few days, and the remaining 10%.
% only lasts a few seconds
.
frequency of seizures
.
Some studies have shown that the frequency of VM vertigo attacks is significantly higher than that of BPPV.
The former is measured in days, and the latter is measured in weeks.
VM attacks are more frequent, especially in the case of repeated recurrence of suspected BPPV, which requires repeated reduction treatment, and even a single attack can be achieved by repeated reduction.
Patients with suboptimal response to treatment should consider excluding VM
.
Mastering the nystagmus characteristics of BPPV and VM Nystagmus is an important sign of vestibular disease and a key indicator for differential diagnosis of related diseases
.
Published online on June 14, 2019 in the Vestibular Research (J Ves Res) electronic edition, the Barani Society Classification Committee of Vestibular Disorders defines nystagmus as an involuntary, rapid rhythmic oscillating eye movement with at least 1 Slow phase
.
Nystagmus is divided into physiological nystagmus and pathological nystagmus, the latter including spontaneous nystagmus, gaze-evoked nystagmus, and triggered nystagmus
.
Triggered nystagmus includes benign paroxysmal positional nystagmus (BPPN) and central positional nystagmus (CPN)
.
BPPN is a specific nystagmus related to a specific semicircular canal plane induced by head movement to a new position.
It has the characteristics of short onset time, latency, fatigue, and angular acceleration movement correlation.
It is a peripheral vestibular disease nystagmus
.
The nystagmus of VM is CPN, which is characterized by diversity, variability, and not characterized by fixed semicircular canals.
It is a central vestibular disease nystagmus
.
The detection of nystagmus with different characteristics is an important basis for differentiating BPPV and VM, but nystagmus examination in clinical work will be limited by the examiner's experience and equipment, so correct clinical diagnosis ideas are needed in order to reduce deviations
.
Professor Jiang Zidong emphasized: "The judgment of BPPN must conform to the description of its diagnostic criteria", and also listed the detailed clinical diagnosis ideas for us: (1) BPPN has false negatives during the induction process, and the patient's head is placed on the patient's head at the beginning of the induction test.
It is in a vertical position parallel to the gravity line of the semicircular canal to be tested.
During the inspection, keep the head in the plane of the semicircular canal to be tested.
Only then can the maximum intensity of BPPN be recorded, which is helpful to identify the laterality of the BPPV and the semicircular canal responsible
.
(2) In the posterior semicircular canal BPPV position induction test, the patient had torsional nystagmus in the suspended head position, and the direction of the nystagmus was reversed when returning to the sitting position, that is, torsional nystagmus.
If the nystagmus does not reverse, it may be VM
.
(3) Spontaneous nystagmus does not occur in BPPV, and BPPV may produce nystagmus in the median gaze position during direct vision, which is called pseudo-spontaneous nystagmus
.
Tilt the head forward 30° and the nystagmus disappears.
When the head is tilted further forward, the direction of the nystagmus is reversed, which is essentially another form of triggered nystagmus
.
(4) In the horizontal semicircular canal BPPV position induction test, the patient presented with horizontal direction changing positional nystamus (DCPN).
The strength of the nystagmus assists in judging the side of the responsible semicircular canal and the direction of the nystagmus.
Determine whether a tube stone or a curled cap stone
.
If non-DCPN occurs during the diagnosis and treatment of BPPV, or the nystagmus changes from geotropism to epicenter, it may be related to otolith ectopic, and it may also indicate VM or light capping
.
(5) Anterior semicircular canal and multisemicircular canal BPPV are rare, especially in the face of poor effect of repeated reduction, inducing vertical nystagmus, and being diagnosed as refractory BPPV patients, it is necessary to exclude central diseases including VM, vestibular paroxysms, congenital Skull base malformations and fourth ventricle tumors
.
Other skills and key points The treatment of VM includes patient management and drug therapy, and the rational selection of therapeutic drugs is the key to the treatment and prevention of recurrent dizziness/vertigo in VM
.
Otolith repositioning therapy is ineffective for positional vertigo and nystagmus in patients with VM.
When it is clinically highly suspected that BPPV is ineffective for repeated treatment, or patients with repeated recurrence, careful evaluation is required to exclude VM
.
At the same time, in the process of BPPV diagnosis and treatment, standardized diagnosis and treatment is very important
.
In the 2015 version of the BPPV diagnostic criteria and the 2017 version of the BPPV clinical practice guidelines, there was no breakthrough in the understanding of the pathogenesis of BPPV, and the otolith theory (including the theory of canal and cap stones) is still a generally accepted theory.
The dislodged otolith falls into the semicircular canal or adheres to the cap of the ampulla ridge of the semicircular canal.
When the head moves in the plane of the involved semicircular canal, the otolith's gravitational direction changes and stimulates the vestibular terminal receptors, and the excitatory vestibular signal goes from the outer circumference to the outer circumference Central transmission, causing dizziness/vertigo and nystagmus
.
The presence of symptoms of dizziness/vertigo and the presence of nystagmus specific to the involved semicircular canals in a position-specific provocation test (Dix-hallpike or head roll test) are critical for the diagnosis of BPPV
.
The main points of BPPV treatment include: (1) During the repositioning process of BPPV, keeping the head rotating in the plane of the semicircular canal to be tested not only induces positional nystagmus of maximum intensity, but also is the key to the success of manual repositioning
.
(2) The treatment of BPPV needs to be standardized, that is, for typical BPPV, once the diagnosis is clear, manual reduction treatment can be performed in time, and pure tone audiometry, vestibular function, and inner ear and cranial imaging examinations are not considered for the time being
.
(3) The patient's original positional vertigo/dizziness and nystagmus disappeared after manual reduction treatment, which supports the diagnosis of BPPV
.
8 points for clinical practice according to the diagnosis and treatment guidelines 1.
During the diagnosis and treatment of BPPV, the concepts of atypical BPPV and subjective benign paroxysmal positional vertigo (SBPPV) that have appeared in the past are easily confused with VM
.
2.
Tirelli et al.
conducted a controlled study on dizziness patients without nystagmus and dizziness patients with typical nystagmus, and found that there is atypical BPPV, and its treatment is not significantly different from typical BPPV
.
3.
Haynes et al.
proposed the concept of subjective BPPV.
They called patients with typical symptoms, negative BPPN, but good effect of manual reduction as SBPPV; patients with typical symptoms, positive BPPN, and good effect of manual reduction were called objective BPPV ( objective benign paroxysmal positional vertigo, OBPPV)
.
4.
In the 2015 new version of BPPV diagnostic criteria, SBPPV with onset time less than 1 min and exclusion of other vestibular diseases was defined as spontaneous remission and possible BPPV
.
5.
The pathogenesis of BPPV is the otolith theory.
The current inspection methods cannot directly show how the otolith fall off and cause vertigo and nystagmus, and how the manipulation of the otolith can restore the otolith and cause the vertigo and nystagmus to disappear.
According to the position test The characteristics and direction of the induced nystagmus in the semicircular canal to determine the responsibility of the otolith fall off, so as to choose the correct reset method
.
Nystagmus is an objective basis for diagnosis and treatment, but the only objective indicator of BPPV subtypes with spontaneous remission and possible BPPV is missing, which easily affects the judgment of doctors, and clinical diagnosis and treatment are risky and challenging
.
In the annotations and comments of the 2015 version of the BPPV standard, the identification of this type of BPPV and VM is particularly emphasized to avoid misdiagnosis and mistreatment
.
6.
The frequency of dizziness/vertigo episodes is different between BPPV and VM patients.
The former is measured in weeks and the latter is in days.
VM attacks are more frequent, and BPPV with repeated otolith repositioning and treatment, or BPPV with poor repeated treatment effect needs to be treated.
Exclude VMs
.
7.
In the face of refractory BPPV, it is necessary to exclude VM before surgery, especially in patients with refractory BPPV who are going to undergo surgical treatment
.
Leveque et al.
found that the number of cases of refractory BPPV treated by surgery decreased significantly after 1990, because in the late 1980s, the existence of horizontal semicircular canal and superior semicircular canal BPPV was recognized, and their clinical characteristics were different from those of posterior semicircular canal BPPV.
And effective manual reduction method, so that those patients who were misdiagnosed as posterior semicircular canal BPPV due to the limited level of diagnosis and treatment are not difficult to treat
.
8.
Reflections and lessons from the clinical practice of BPPV are: for self-limiting diseases, especially for benign diseases, when the treatment plan may potentially harm the patient, sometimes it is worth waiting and observing, avoiding excessive surgical treatment or destructive treatment
.
This article is compiled from the wonderful lecture given by Professor Jiang Zidong of Peking Union Medical College Hospital at the 2021 Cerebrovascular Disease Beijing Forum - "Discussing Otolithiasis Repositioning Skills and Discrimination of Vestibular Migraine"
.
