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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

Stimulation of the posterior semicircular canal during the right Dix-Hallpike maneuver (c). On (a,b), the semicircular canals of the left and right ears, respectively, are shown. When otoconia is present in the ipsilateral (right) posterior canal (b), the maneuver causes its movement along the lumen of the canal, inducing BPPV. When otoconia is present in the contralateral (left) posterior canal (a), the maneuver does not cause any movement of the otoconia, because the head rotates orthogonally to the plane of the involved canal and the maneuver is negative.
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fig1: Stimulation of the posterior semicircular canal during the right Dix-Hallpike maneuver (c). On (a,b), the semicircular canals of the left and right ears, respectively, are shown. When otoconia is present in the ipsilateral (right) posterior canal (b), the maneuver causes its movement along the lumen of the canal, inducing BPPV. When otoconia is present in the contralateral (left) posterior canal (a), the maneuver does not cause any movement of the otoconia, because the head rotates orthogonally to the plane of the involved canal and the maneuver is negative.

Mentions: The previously described profile of nystagmus correlates with the known neuromuscular pathways that arise from stimulation of the posterior canal ampullary nerves in animal models and humans [9, 10]. It should be noticed that the character of nystagmus changes with the direction of gaze, which is explained by contraction of the ipsilateral superior oblique and contralateral inferior rectus, following the stimulation of the posterior canal. When the patient lies in the lateral head hanging position, if he looks towards the uppermost unaffected ear, the axes of these two extraocular muscles nearly coincide, resulting in movement of the eyes in a vertical plane with predominance of the vertical component of the nystagmus. When looking towards the lowermost involved ear, the axes of these two muscles are nearly at right angles with the direction of the gaze, and their contraction results in apogeotropic rolling of the upper pole of the eye (slow phase) and predominance of the torsional component of the nystagmus with geotropic fast phase [11]. The Dix-Hallpike maneuver is usually positive only when performed with the involved ear undermost and negative on the contralateral side, permitting thus easy localization of the side of the lesion (Figure 1). It should be also noticed, that posterior canal paroxysmal positional nystagmus is dissociated, with the torsional component being more evident in the ipsilateral eye, and the vertical upbeating component more evident in the contralateral eye, which can be explained by different angle of insertion of the oblique and rectus muscles [12, 13]. In Table 1, the various types of BPPV nystagmus are described, according to the involved semicircular canal and the side of involvement.


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)

Stimulation of the posterior semicircular canal during the right Dix-Hallpike maneuver (c). On (a,b), the semicircular canals of the left and right ears, respectively, are shown. When otoconia is present in the ipsilateral (right) posterior canal (b), the maneuver causes its movement along the lumen of the canal, inducing BPPV. When otoconia is present in the contralateral (left) posterior canal (a), the maneuver does not cause any movement of the otoconia, because the head rotates orthogonally to the plane of the involved canal and the maneuver is negative.
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig1: Stimulation of the posterior semicircular canal during the right Dix-Hallpike maneuver (c). On (a,b), the semicircular canals of the left and right ears, respectively, are shown. When otoconia is present in the ipsilateral (right) posterior canal (b), the maneuver causes its movement along the lumen of the canal, inducing BPPV. When otoconia is present in the contralateral (left) posterior canal (a), the maneuver does not cause any movement of the otoconia, because the head rotates orthogonally to the plane of the involved canal and the maneuver is negative.
Mentions: The previously described profile of nystagmus correlates with the known neuromuscular pathways that arise from stimulation of the posterior canal ampullary nerves in animal models and humans [9, 10]. It should be noticed that the character of nystagmus changes with the direction of gaze, which is explained by contraction of the ipsilateral superior oblique and contralateral inferior rectus, following the stimulation of the posterior canal. When the patient lies in the lateral head hanging position, if he looks towards the uppermost unaffected ear, the axes of these two extraocular muscles nearly coincide, resulting in movement of the eyes in a vertical plane with predominance of the vertical component of the nystagmus. When looking towards the lowermost involved ear, the axes of these two muscles are nearly at right angles with the direction of the gaze, and their contraction results in apogeotropic rolling of the upper pole of the eye (slow phase) and predominance of the torsional component of the nystagmus with geotropic fast phase [11]. The Dix-Hallpike maneuver is usually positive only when performed with the involved ear undermost and negative on the contralateral side, permitting thus easy localization of the side of the lesion (Figure 1). It should be also noticed, that posterior canal paroxysmal positional nystagmus is dissociated, with the torsional component being more evident in the ipsilateral eye, and the vertical upbeating component more evident in the contralateral eye, which can be explained by different angle of insertion of the oblique and rectus muscles [12, 13]. In Table 1, the various types of BPPV nystagmus are described, according to the involved semicircular canal and the side of involvement.

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