Limits...
Diagnosis of Single- or Multiple-Canal Benign Paroxysmal Positional Vertigo according to the Type of Nystagmus.

Balatsouras DG, Koukoutsis G, Ganelis P, Korres GS, Kaberos A - Int J Otolaryngol (2011)

Bottom Line: Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics.It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test.Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers.

View Article: PubMed Central - PubMed

Affiliation: ENT Department, Tzanio General Hospital of Piraeus, Afentouli 1 and Zanni, 18536 Piraeus, Greece.

ABSTRACT
Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics. It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test. Current clinical research focused on diagnosing and treating various types of BPPV, according to the semicircular canal involved and according to the implicated pathogenetic mechanism. Cases of multiple-canal BPPV have been specifically investigated because until recently these were resistant to treatment with standard canalith repositioning procedures. Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers. We describe in detail the various types of nystagmus, according to the canals involved, which are the keypoint to accurate diagnosis.

No MeSH data available.


Related in: MedlinePlus

Mechanism of canalolithiasis of BPPV of the horizontal semicircular canal, when the left ear is affected (the involved left horizontal canal is colored black). (a) Patient in supine position with debris in the posterior part of the left horizontal canal. (b) When rotating the head towards the affected side, particles move towards the ampulla, producing an ampullopetal flow and triggering intense geotropic horizontal nystagmus. (c) When rotating the head towards the healthy side, particles fall in the opposite direction, causing an ampullofugal flow and triggering nystagmus beating again towards the ground, but less intense.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3139887&req=5

fig2: Mechanism of canalolithiasis of BPPV of the horizontal semicircular canal, when the left ear is affected (the involved left horizontal canal is colored black). (a) Patient in supine position with debris in the posterior part of the left horizontal canal. (b) When rotating the head towards the affected side, particles move towards the ampulla, producing an ampullopetal flow and triggering intense geotropic horizontal nystagmus. (c) When rotating the head towards the healthy side, particles fall in the opposite direction, causing an ampullofugal flow and triggering nystagmus beating again towards the ground, but less intense.

Mentions: This is the most common type of horizontal canal involvement, accounting for approximately 2/3 of the cases [2, 18]. The canalolithiasis theory can also explain this BPPV variant. Degenerative debris enter the nonampullary side of the pathological horizontal canal when the patient lies supine (Figure 2(a)). Diagnosis is made by the supine roll test, turning the head from the supine to either lateral position. When rotating the head to the pathological side (Figure 2(b)), gravity and the angular head acceleration make the mass descend in the canal towards the ampulla. The movement of the clot continues until the deepest position is reached and provokes an ampullopetal deviation of the cupula, resulting in a burst of nystagmus towards the ground. When maintaining the head rotation to the pathological side, a burst of nystagmus with opposite fast phase (away from the ground) can be seen. This may be attributed to short-term adaptation of the vestibule-ocular reflex [19] or to an inversion of the direction of clot movement, due to a spontaneous reflux of endolymph between debris in the canal and membranous walls, facilitated by the elastic forces of the cupula. Another possibility is mixed canalolithiasis-cupulolithiasis, which may initially manifest as intense paroxysmal geotropical nystagmus owed to canalolithiasis, superimposed over the opposite nystagmus of cupulolithiasis, followed by the apogeotropical persistent nystagmus of cupulolithiasis. The same type of nystagmus can also be obtained by returning the head to the original position. When the head is rotated to the healthy side (Figure 2(c)), the mass is displaced further towards the nonampullary end of the canal with an ampullofugal displacement of the cupula, resulting in a nystagmus of lower intensity, beating towards the ground. Latency is usually shorter in horizontal canal BPPV. To summarize, horizontal canal BPPV owed to canalolithiasis manifests as bilateral geotropic horizontal nystagmus, which is more pronounced in the pathological side. This type of nystagmus is characterized by a short latency, a very sudden onset, and a longer duration as compared with the paroxysmal nystagmus of the posterior canal.


Diagnosis of Single- or Multiple-Canal Benign Paroxysmal Positional Vertigo according to the Type of Nystagmus.

Balatsouras DG, Koukoutsis G, Ganelis P, Korres GS, Kaberos A - Int J Otolaryngol (2011)

Mechanism of canalolithiasis of BPPV of the horizontal semicircular canal, when the left ear is affected (the involved left horizontal canal is colored black). (a) Patient in supine position with debris in the posterior part of the left horizontal canal. (b) When rotating the head towards the affected side, particles move towards the ampulla, producing an ampullopetal flow and triggering intense geotropic horizontal nystagmus. (c) When rotating the head towards the healthy side, particles fall in the opposite direction, causing an ampullofugal flow and triggering nystagmus beating again towards the ground, but less intense.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3139887&req=5

fig2: Mechanism of canalolithiasis of BPPV of the horizontal semicircular canal, when the left ear is affected (the involved left horizontal canal is colored black). (a) Patient in supine position with debris in the posterior part of the left horizontal canal. (b) When rotating the head towards the affected side, particles move towards the ampulla, producing an ampullopetal flow and triggering intense geotropic horizontal nystagmus. (c) When rotating the head towards the healthy side, particles fall in the opposite direction, causing an ampullofugal flow and triggering nystagmus beating again towards the ground, but less intense.
Mentions: This is the most common type of horizontal canal involvement, accounting for approximately 2/3 of the cases [2, 18]. The canalolithiasis theory can also explain this BPPV variant. Degenerative debris enter the nonampullary side of the pathological horizontal canal when the patient lies supine (Figure 2(a)). Diagnosis is made by the supine roll test, turning the head from the supine to either lateral position. When rotating the head to the pathological side (Figure 2(b)), gravity and the angular head acceleration make the mass descend in the canal towards the ampulla. The movement of the clot continues until the deepest position is reached and provokes an ampullopetal deviation of the cupula, resulting in a burst of nystagmus towards the ground. When maintaining the head rotation to the pathological side, a burst of nystagmus with opposite fast phase (away from the ground) can be seen. This may be attributed to short-term adaptation of the vestibule-ocular reflex [19] or to an inversion of the direction of clot movement, due to a spontaneous reflux of endolymph between debris in the canal and membranous walls, facilitated by the elastic forces of the cupula. Another possibility is mixed canalolithiasis-cupulolithiasis, which may initially manifest as intense paroxysmal geotropical nystagmus owed to canalolithiasis, superimposed over the opposite nystagmus of cupulolithiasis, followed by the apogeotropical persistent nystagmus of cupulolithiasis. The same type of nystagmus can also be obtained by returning the head to the original position. When the head is rotated to the healthy side (Figure 2(c)), the mass is displaced further towards the nonampullary end of the canal with an ampullofugal displacement of the cupula, resulting in a nystagmus of lower intensity, beating towards the ground. Latency is usually shorter in horizontal canal BPPV. To summarize, horizontal canal BPPV owed to canalolithiasis manifests as bilateral geotropic horizontal nystagmus, which is more pronounced in the pathological side. This type of nystagmus is characterized by a short latency, a very sudden onset, and a longer duration as compared with the paroxysmal nystagmus of the posterior canal.

Bottom Line: Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics.It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test.Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers.

View Article: PubMed Central - PubMed

Affiliation: ENT Department, Tzanio General Hospital of Piraeus, Afentouli 1 and Zanni, 18536 Piraeus, Greece.

ABSTRACT
Benign paroxysmal positional vertigo (BPPV) is a common peripheral vestibular disorder encountered in primary care and specialist otolaryngology and neurology clinics. It is associated with a characteristic paroxysmal positional nystagmus, which can be elicited with specific diagnostic positional maneuvers, such as the Dix-Hallpike test and the supine roll test. Current clinical research focused on diagnosing and treating various types of BPPV, according to the semicircular canal involved and according to the implicated pathogenetic mechanism. Cases of multiple-canal BPPV have been specifically investigated because until recently these were resistant to treatment with standard canalith repositioning procedures. Probably, the most significant factor in diagnosis of the type of BPPV is observation of the provoked nystagmus, during the diagnostic positional maneuvers. We describe in detail the various types of nystagmus, according to the canals involved, which are the keypoint to accurate diagnosis.

No MeSH data available.


Related in: MedlinePlus