Persistent Geotropic Positional Nystagmus Research Articles

Less talked variants of benign paroxysmal positional vertigo

The diagnostic criteria were established for benign paroxysmal positional vertigo (BPPV), the most common vestibular disorder worldwide, by the Barany Society in 2015. This marked an important milestone in the diagnosis and treatment of BPPV. However, there still remain uncertainties and ambiguities regarding the clinical features and pathophysiology of BPPV, and its clinical variants. In this manuscript, we will discuss 1) the emerging and controversial syndromes of BPPV (i.e., canalolithiasis of the anterior canal, cupulolthiasis of the posterior canal, and lithiasis of multiple canals) with updates, 2) atypical nystagmus according to the canal involved (e.g., nystagmus induced by head position changes in the pitch plane in horizontal canal BPPV, and positional downbeat nystagmus in posterior canal BPPV), 3) persistent geotropic positional nystagmus. Consideration of these uncommon types and manifestations of BPPV would broaden our understanding of BPPV pathomechanisms and allow differentiation from central vertigo and nystagmus.

Clinical Characteristics of Patients With Benign Paroxysmal Positional Vertigo Diagnosed Based on the Diagnostic Criteria of the Bárány Society.

Objectives: To analyze the clinical characteristics of patients with benign paroxysmal positional vertigo (BPPV) diagnosed based on the diagnostic criteria of Bárány Society, verify the clinical application value of the diagnostic criteria, and further explore the clinical problems associated with the diagnosis of possible BPPV.Methods: A total of 481 patients with BPPV who were admitted from March 2016 to February 2019 were included. All patients were diagnosed by the Dix-Hallpike, straight head hanging and supine roll tests, the nystagmus was recorded using videonystagmography. For patients with possible BPPV (uncertain diagnosis), particle repositioning therapy and follow-up diagnosis were used to further clarify diagnosis.Results: Based on Bárány Society's diagnostic criteria for BPPV, the distribution characteristics of different BPPV types were as follows: 159 (33.1%) patients had posterior canal BPPV-canalolithiasis (PC-BPPV-ca), 70 (14.6%) patients had horizontal canal BPPV-ca (HC-BPPV-ca), 55 (11.4%) patients had spontaneously resolved-probable-BPPV (Pro-BPPV), and 53 (11.0%) patients had HC-BPPV-cupulolithiasis (HC-BPPV-cu). In emerging and controversial BPPV, 51 (10.6%) patients had multiple canal BPPV (MC-BPPV), 30 (6.2%) patients had PC-BPPV-cu, and 19 (4.0%) patients had anterior canal BPPV-ca (AC-BPPV-ca), 44 (9.1%) patients had possible-BPPV (Pos-BPPV). Among the 44 patients with Pos-BPPV, 23 patients showed dizziness/vertigo without nystagmus during the initial positional test, five patients were possible MC-BPPV, four patients had persistent geotropic positional nystagmus lasting > 1 min when lying on both sides, and were considered to have Pos-HC-BPPV, four patients showed apogeotropic nystagmus when lying on one side, and were considered to have possible short-arm HC-BPPV, four patients showed geotropic nystagmus when lying on one side, and were considered to have Pos-HC-BPPV, three patients had down-beating nystagmus, lasing > 1 min, were considered to have Pos-AC-BPPV-cu. One patient showed transient apogeotropic positional nystagmus on both sides during the supine roll test, and was diagnosed with possible anterior arm HC-BPPV.Conclusions: PC-BPPV-ca is the most common among patients with BPPV, followed by HC-BPPV-ca. In emerging and controversial BPPV, MC-BPPV, and Pos-BPPV were more common. For the diagnosis of Pos-BPPV, a combination of the history of typical BPPV, particle repositioning therapy and follow-up outcome is helpful to clarify the diagnosis.

Recurrence in patients with benign paroxysmal positional vertigo of the lateral semicircular canal

ObjectivesThere are 3 subtypes of lateral canal benign paroxysmal positional vertigo. Persistent geotropic positional nystagmus is due to a light cupula, heavy cupula produces apogeotropic positional nystagmus, and canalolithiasis accounts for transient geotropic positional nystagmus. The aims of this study were to determine the recurrence rate and to examine the number of times of recurrence in each of the 3 subtypes. MethodsSubjects were patients with light cupula (n = 47), heavy cupula (n = 48), and canalolithiasis (n = 45). We investigated the number of times of recurrence and determined the subtypes of a recurrent vertigo attack over the period of 5 years. ResultsThe subtype of a recurrent vertigo attack was not always the same as the subtype at the first visit. The recurrence rate of light cupula group was 72.3%, that of heavy cupula group was 20.8%, and that of canalolithiasis group was 28.9%. Some patients experienced recurrence more than once. The mean value and standard deviation of the number of times of recurrence in light cupula group was 2.5 ± 1.3 times, that in heavy cupula group was 1.5 ± 0.7 times, and that in canalolithiasis group was 1.5 ± 0.7 times. ConclusionsThe recurrence rate in patients with light cupula is much higher than that in patients with heavy cupula or canalolithiasis. The number of times of recurrence in patients with light cupula is greater than that in patients with heavy cupula or canalolithiasis.

Persistent geotropic positional nystagmus in unilateral cerebellar lesions.

To determine the prevalence of central lesions in persistent geotropic positional nystagmus, and characteristics and anatomical substrates of the nystagmus in cerebellar lesions. We prospectively recruited 58 patients with persistent geotropic positional nystagmus at the Dizziness Clinic of Pusan National University Hospital. Seven patients with unilateral cerebellar lesions were subjected to analysis of clinical characteristics, oculographic data, and MRI lesions. For comparison, we studied 37 cases of peripheral persistent geotropic positional nystagmus. The prevalence of central lesions in persistent geotropic positional nystagmus was 12% (7/58). Persistent geotropic positional nystagmus in cerebellar lesions was mostly asymmetrical. Horizontal nystagmus changed in direction during the bow-and-lean test with null positions. All patients showed impaired horizontal smooth pursuit bilaterally, and 3 of them also had positional downbeat nystagmus. The peak intensity and asymmetry of persistent geotropic positional nystagmus did not differ between central and peripheral groups (p > 0.05), while there was a difference in the maxima. Lesion overlays revealed that damage to the cerebellar tonsil was responsible for the generation of persistent geotropic positional nystagmus. Although persistent geotropic positional nystagmus in cerebellar lesions shares the characteristics of nystagmus measures with peripheral cases, accompanying central oculomotor signs can aid in differentiation. In tonsillar lesions, compensatory rotational feedback due to erroneous estimation of the direction of gravity may generate constant horizontal geotropic positional nystagmus.

Office-based differential diagnosis of transient and persistent geotropic positional nystagmus in patients with horizontal canal type of benign paroxysmal positional vertigo

Conclusion: A 30 s observation of geotropic positional nystagmus is sufficient to distinguish persistent geotropic positional nystagmus (PGPN) from transient geotropic positional nystagmus (TGPN) in patients with horizontal canal type of benign paroxysmal positional vertigo (H-BPPV) in ENT office.Objective: As a canalith repositioning procedure effectively treats H-BPPV with TGPN, but not PGPN, the differentiation between patients with PGPN and with TGPN is essential. The purpose of this study is to determine the observation period enough to distinguish TGPN from PGPN.Methods: This study first analyzed positional nystagmus images recorded with an infrared CCD camera three-dimensionally in 47 patients with H-BPPV. PGPN is distinguished from TGPN in patients with H-BPPV precisely by means of time constant calculated form analysis of positional nystagmus. Ten-second and 30-s movies were made of positional nystagmus of the all 47 patients. Ten independent otolaryngologists were then asked to distinguish TGPN from PGPN after a 10 s or 30 s observation of the geotropic positional nystagmus images in 47 patients with H-BPPV.Results: The sensitivity and specificity to distinguish TGPN from PGPN was 100% and 97% after 30 s observation, but 100% and 40% after 10 s observation, respectively.

Light cupula: the pathophysiological basis of persistent geotropic positional nystagmus

ObjectiveTo clarify the pathophysiological basis of persistent geotropic positional nystagmus (PGN) in patients with the horizontal canal type of benign paroxysmal positional vertigo (H-BPPV), the time constant (TC) of nystagmus...

Persistent geotropic nystagmus—a different kind of cupular pathology and its localizing signs

Conclusion. A persistent geotropic positional nystagmus indicates a dysfunction in the lateral semicircular canal with a cupula of less specific weight than the surrounding endolymph. It is possible to determine the side of the affected cupula by recording the nystagmus pattern in yaw and pitch plane. Objectives. To identify the clinical features in patients with a persistent geotropic positional nystagmus, establish lateralizing signs and relate the findings to a pathophysiologic mechanism. Patients and methods. Six patients with acute onset vertigo of a peripheral origin and persistent geotropic nystagmus were examined with videonystagmoscopy and the nystagmus characteristics in different positions of the head in yaw and pitch plane were studied. Results. Besides the persistent geotropic nystagmus, a zero zone was found with no nystagmus, beyond which the nystagmus changed direction when the head of the patient in supine position was gradually rotated from side to side. The zero zone was present when the head was turned slightly towards one side and is thought to represent a position where the affected cupula is aligned with the gravitational vertical. With the head bent forwards the nystagmus direction was to the non-affected side and when the head was bent backwards to the affected side.

Marriage of two complete albinos with normally pigmented offspring.

<h3>Objective</h3> To clarify the pathophysiological basis of persistent geotropic positional nystagmus (PGN) in patients with the horizontal canal type of benign paroxysmal positional vertigo (H-BPPV), the time constant (TC) of nystagmus and the relationship between its slow phase eye velocity (SPV) and the angle of head rotation in supine were defined. <h3>Methods</h3> Geotropic or apogeotropic positional nystagmus was recorded by video-oculography and analysed three-dimensionally. <h3>Results</h3> Geotropic positional nystagmuses in patients with H-BPPV were classified as transient geotropic positional nystagmus with a TC of ≤35 s or PGN with a TC of &gt;35 s. Alternatively, the TC of persistent apogeotropic positional nystagmus (AN) in patients with H-BPPV was &gt;35 s. The direction of the SPV of patients with PGN was opposite to that of patients with AN at each head position across the range of neutral head positions. The relationship between the SPV of patients with PGN and the angle of head rotation was linearly symmetrical against that of patients with AN with respect to a line drawn on the neutral head position. <h3>Conclusions</h3> Since its TC was &gt;35 s, it is suggested that PGN is induced by cupula deviation in response to gravity at each head position. It is also suggested that the direction of cupula deviation in patients with PGN is opposite to that of patients with AN across the neutral head positional range with no nystagmus where the long axis of cupula is in alignment with the axis of gravity. Since the pathophysiological basis of AN is considered a heavy cupula, it is suggested that PGN is conversely induced by a light cupula.