Benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is characterized by positional vertigo (brief attacks of rotatory vertigo triggered by head position changes in the direction of gravity) and is the most common peripheral cause of vertigo. There are two types of BPPV pathophysiology: canalolithiasis and cupulolithiasis. In canalolithiasis, otoconial debris is detached from the otolithic membrane and floats freely within the endolymph of the canal. In cupulolithiasis, the otoconial debris released from the otolithic membrane settles on the cupula of the semicircular canal and the specific gravity of the cupula is increased. Consensus has been reached regarding three subtypes of BPPV: posterior-canal-type BPPV (canalolithiasis), lateral-canal-type BPPV (canalolithiasis) and lateral-canal-type BPPV (cupulolithiasis). In the interview-based medical examination of BPPV, questions regarding the characteristics of vertigo, triggered movement of vertigo, duration of vertigo and cochlear symptoms during vertigo attacks are important for the diagnosis of BPPV. The Dix–Hallpike test is a positioning nystagmus test used for diagnosis of posterior-canal-type BPPV. The head roll test is a positional nystagmus test used for diagnosis of lateral-canal-type BPPV. When the Dix–Hallpike test is repeated, positional nystagmus and the feeling of vertigo typically become weaker. This phenomenon is called BPPV fatigue. The effect of BPPV fatigue typically disappears within 30 min, at which point the Dix–Hallpike test again induces clear positional nystagmus even though BPPV fatigue had previously caused the positional nystagmus to disappear. For the treatment of BPPV, sequential head movements of patients can cause the otoconial debris in the semicircular canal to move to the utricle. This series of head movements is called the canalith repositioning procedure (CRP). The appropriate type of CRP depends on the semicircular canal in which the otoconial debris is located. The CRP for posterior-canal-type BPPV is called the Epley maneuver, and the CRP for lateral-canal-type BPPV is called the Gufoni maneuver. Including a time interval between each head position in the Epley maneuver reduces the immediate effect of the maneuver. This finding can inform the development of methods for reducing the effort exerted by doctors and the discomfort experienced by patients with posterior-canal-type BPPV during the Epley maneuver.     

Horizontal canal type BPPV: bilaterally affected case treated with canal plugging and Lempert's maneuver

A 54-year-old woman complained of positional vertigo. During 3 months' observation, the patient showed mostly geotropic or apogeotropic nystagmus due to right canalolithiasis or cupulolithiasis, however, she sometimes showed nystagmus which suggested left horizontal canalolithiasis. We suspected that she suffered from bilateral horizontal canal type benign paroxysmal positional vertigo (BPPV) and performed Lempert's maneuver for both directions, however, they were ineffective. She underwent canal plugging for right horizontal canal. After surgery she showed no positional nystagmus of right horizontal canal origin. However, apogeotropic nystagmus of the left horizontal canal origin was still observed. This nystagmus changed to geotropic nystagmus and finally disappeared following Lempert's maneuver for the left side. Bilateral horizontal canal BPPV is difficult to be resolved, probably because physical treatment for one side would move debris to the cupula in the other canal. Canal plugging combined with Lempert's maneuver to the other side is one treatment option for intractable bilateral horizontal canal BPPV.     

Conversion of canalolithiasis to cupulolithiasis in the course of a horizontal benign paroxysmal positional vertigo case

The benign paroxysmal positional vertigo of the horizontal semicircular canal is manifested with either geotropic or apogeotropic horizontal nystagmus. A 61-year-old male patient who experienced repeated episodes of positional vertigo is presented in this study. The vertigo was reported to be more severe while rotating his head to the left and then to the right. The initial examination revealed a geotropic purely horizontal nystagmus at the lateral positions of the head compatible with canalolithiasis of the left horizontal semicircular canal. In this case, the otoconia debris migrates from the vestibule into the horizontal semicircular canal through its nonampullary end, where they float freely (canalolithiasis). Five days later, the geotropic nystagmus transformed to apogeotropic. Thus, it may be assumed that the otoconia debris adhered to the cupula and converted the canalolithiasis to cupulolithiasis of the horizontal semicircular canal on the same side. With rotation of the head to the left while the patient was in the supine position, gravity causes the weighted cupula to deflect ampullofugally, resulting in apogeotropic nystagmus; the opposite was noticed when the head was rotated to the right. The so-called barbecue maneuver was initially effective curing the geotropic form of the condition and consequently the modified Semont maneuver for the apogeotropic form.     

Benign paroxysmal positional vertigo showing sequential translations of four types of nystagmus

Objective

We report a case of benign paroxysmal positional vertigo (BPPV) showing sequential translation of four types of nystagmus and discuss its pathophysiology.

Methods

The case was 65-year-old female. We analyzed her nystagmus three-dimensionally.

Results

At the first visit, she showed vertical-torsio nystagmus of the posterior canal type of BPPV (P-BPPV) and subsequently showed recently reported geotropic nystagmus with a long time constant. Two weeks later, she showed apogeotropic nystagmus of the horizontal canal type of BPPV (AH-BPPV) and subsequently a geotropic nystagmus with a short time constant of the horizontal canal type of BPPV (GH-BPPV).

Conclusions

Three kind of nystagmus, namely P-BPPV, AH-BPPV and GH-BPPV can be explained by the otoconial debris hypothesis of the same ear. Finally, the recently reported geotropic nystagmus with a long time constant may be explained by a reversible lesion such as the denatured cupula or utricular imbalance of the same ear.     

Clinical effect of canal plugging on paroxysmal positional vertigo

A 63-year-old woman had disabling positional vertigo for four months. She showed intense direction-changing apogeotropic nystagmus. Conservative treatment failed to resolve her vertigo. From the findings of the nystagmus, cupulolithiasis of the right lateral canal was suspected. Plugging of this canal successfully eliminated the nystagmus and positional vertigo. Positional vertigo can sometimes be disabling and unresponsive to conservative therapy. Careful analysis of the nystagmus may allow selection of the most appropriate treatment.     

外半规管良性阵发性位置性眩晕的诊疗

良性阵发性位置性眩晕(benign paroxysmal positional vertigo,BPPV)是最常见的周围性眩晕,主要表现为随头位变化出现的短暂性眩晕发作,该病分为后半规管型、外半规管型、上半规管型及多半规管.其中后半规管BPPV最常见,其次为外半规管BPPVo外半规管BPPV根据发病机制、原理、眼震方向等有多种分类方法.近年来外半规管BPPV的手法复位逐渐被熟悉,但一些患者复位后效果不佳,如外半规管嵴帽结石症,部分患者行常规手法复位后发作性眩晕仍然存在.我们将这部分手法复位后眩晕症状改善不明显的类型归结为难治型外半规管嵴帽结石症.本文主要围绕外半规管BPPV的概念及分类、流行病学、病因、发病机制、诊断及复位方法,尤其对于难治型外半规管嵴帽结石症的复位方法做一综述.     

A cupulolith repositioning maneuver in the treatment of horizontal canal cupulolithiasis

Objective

We evaluated outcomes and their significance of a new treatment method for horizontal canal cupulolithiasis that could be applied regardless of the side of the cupula where otoliths are attached.

Methods

Consecutive 78 patients who showed persistent apogeotropic horizontal canal positional vertigo (horizontal canal cupulolithiasis) were enrolled, and they were treated with the new cupulolith repositioning maneuver.

Results

Horizontal semicircular canal cupulolithiasis was alleviated in 97.4% of patients, after an average of 2.1 repetitions of the maneuver. Otoliths were suspected to be attached to the canal side of the cupula in 30 cases and the utricular side in 44 cases.

Conclusion

The cupulolith repositioning maneuver is an effective method for treating horizontal canal cupulolithiasis. It may also provide an insight into the side of the cupula where otoliths are attached.     

Combined horizontal and posterior canal benign paroxysmal positional vertigo in three patients with head trauma

We report 3 patients who complained of positional vertigo shortly after head trauma. Positional maneuvers performed in the plane of the posterior canal (PC; Dix-Hallpike maneuver) and the horizontal canal (HC; patients were rolled to either side in a supine position with the head raised 30 degrees) revealed a complex positional nystagmus that could only be interpreted as the result of combined PC and HC benign paroxysmal positional vertigo (BPPV). Two patients had a right PC BPPV and an ageotropic HC BPPV, and 1 patient had a bilateral PC BPPV and a left geotropic HC BPPV. All 3 patients were rapidly free of vertigo after the PC BPPV was cured by the Epley maneuver and the geotropic HC BPPV was cured by the Vannucchi method. The ageotropic HC BPPV resolved spontaneously. Neuroimaging (brain computed tomography and/or magnetic resonance imaging scans) findings were normal in all 3 patients. From a physiopathological viewpoint, it is easy to conceive that head trauma could throw otoconial debris into different canals of each labyrinth and be responsible for these combined forms of BPPV. Consequently, in trauma patients with vertigo, it is mandatory to perform the Dix-Hallpike maneuver, as well as supine lateral head turns, in order to diagnose PC BPPV, HC BPPV, or the association of both. Early diagnosis and treatment of BPPV may help to reduce the postconcussion syndrome.     

“Sitting-up vertigo as an expression of posterior semicircular canal heavy cupula and posterior semicircular canal short arm canalolithiasis”

BackgroundVestibular symptoms on sitting-up are frequent on patients seen by vestibular specialists. Recently, a benign paroxysmal positional vertigo (BPPV) variant which elicits vestibular symptoms with oculomotor evidence of posterior semicircular canal (P-SCC) cupula stimulation on sitting-up was described and named sitting-up vertigo BPPV. A periampullar restricted P-SCC canalolithiasis was proposed as a causal mechanism.ObjectiveTo describe new mechanisms of action for the sitting-up vertigo BPPV variant.MethodsEighteen patients with sitting-up vertigo BPPV were examined with a pre-established set of positional maneuvers and follow-up until they resolved their symptoms and clinical findings.ResultsAll patients showed up-beating torsional nystagmus (UBTN) and vestibular symptoms on coming up from either Dix-Hallpike (DHM) or straight head-hanging maneuver. Sixteen out of 18 patients presented a sustained UBTN with an ipsitorsional component to the tested side on half-Hallpike maneuver (HH). A slower persistent contratorsional down-beating nystagmus was found in eleven out 18 patients tested on nose down position (ND).ConclusionsPersistent direction changing positional nystagmus on HH and ND positions indicative of P-SCC heavy cupula was found in 11 patients. A sustained UBTN on HH with the absence of findings on ND, which is suggestive of the presence of P-SCC short arm canalolithiasis, was found on 5 patients. All patients were treated with canalith repositioning maneuvers without success, but they resolved their findings by means of Brandt-Daroff exercises. We propose P-SCC heavy cupula and P-SCC short arm canalolithiasis as two new putative mechanisms for the sitting-up vertigo BPPV variant.     

Benign paroxysmal positional vertigo due to a simultaneous involvement of both horizontal and posterior semicircular canals

From April 2001 to November 2003, we investigated 8 patients with benign paroxysmal positional vertigo (BPPV) that was suspected to simultaneously affect both the horizontal and posterior semicircular canals (HSCC and PSCC). These cases showed typical vertical-torsional nystagmus induced by the Dix-Hallpike maneuver, followed by a horizontal nystagmus. They also showed a direction-changing geotropic or apogeotropic positional nystagmus triggered by lateral head rotations in the supine position. Using the three-dimensional analysis of the positional nystagmus, the rotation axis of the positional nystagmus had a component perpendicular to the plane of PSCC and another component perpendicular to the plane of HSCC. All these findings suggest that BPPV in these patients was a combination of posterior and horizontal canal BPPV. The observation of a vertical-torsional positional nystagmus should prompt the specialist to perform not only the canalith repositioning procedure, but also to execute lateral head turns in the supine position.     

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.     

Dynamics of the vestibulo-ocular reflex in patients with the horizontal semicircular canal variant of benign paroxysmal positional vertigo

Objective Two types of direction-changing positional nystagmus, the geotropic and apogeotropic variants, are observed in patients with the horizontal semicircular canal (HSCC) type of benign paroxysmal positional vertigo (H-BPPV). In this study, we assessed the dynamics of the vestibulo-ocular reflex (VOR) of the HSCC in patients with H-BPPV.

Material and Methods Patients were rotated about the earth-vertical axis at frequencies of 0.1, 0.3, 0.5, 0.7 and 1.0 Hz with a maximum angular velocity of 50°/s. Eye movements were recorded on a video imaging system using an infrared charge-coupled device (CCD) camera, and our new technique for analyzing the rotation vector of eye movements in three dimensions was used.

Results In the patients with geotropic positional nystagmus, there were no differences in VOR gain between rotation to the affected and unaffected sides at frequencies of 0.1–1.0 Hz. Although no differences in VOR gain at frequencies of 0.3–1.0 Hz were noticed in patients with apogeotropic positional nystagmus, the VOR gain at 0.1 Hz was significantly smaller on rotation to the affected compared to the unaffected side.

Conclusion The results indicate that cupulolithiasis in the HSCC affected the dynamics of the HSCC-ocular reflex at 0.1 Hz, but not at higher frequencies, and that canalolithiasis in the HSCC does not change the VOR gain of the HSCC at any frequency. It is suggested that cupulolithiasis causes transient impairment of HSCC function by means of its mechanical restriction of movements of the cupula.     

Dynamics of the vestibulo-ocular reflex in patients with the horizontal semicircular canal variant of benign paroxysmal positional vertigo

OBJECTIVE: Two types of direction-changing positional nystagmus, the geotropic and apogeotropic variants, are observed in patients with the horizontal semicircular canal (HSCC) type of benign paroxysmal positional vertigo (H-BPPV). In this study, we assessed the dynamics of the vestibulo-ocular reflex (VOR) of the HSCC in patients with H-BPPV. MATERIAL AND METHODS: Patients were rotated about the earth-vertical axis at frequencies of 0.1, 0.3, 0.5, 0.7 and 1.0 Hz with a maximum angular velocity of 50 degrees/s. Eye movements were recorded on a video imaging system using an infrared charge-coupled device (CCD) camera, and our new technique for analyzing the rotation vector of eye movements in three dimensions was used. RESULTS: In the patients with geotropic positional nystagmus, there were no differences in VOR gain between rotation to the affected and unaffected sides at frequencies of 0.1-1.0 Hz. Although no differences in VOR gain at frequencies of 0.3-1.0 Hz were noticed in patients with apogeotropic positional nystagmus, the VOR gain at 0.1 Hz was significantly smaller on rotation to the affected compared to the unaffected side. CONCLUSION: The results indicate that cupulolithiasis in the HSCC affected the dynamics of the HSCC-ocular reflex at 0.1 Hz, but not at higher frequencies, and that canalolithiasis in the HSCC does not change the VOR gain of the HSCC at any frequency. It is suggested that cupulolithiasis causes transient impairment of HSCC function by means of its mechanical restriction of movements of the cupula.     

Value of lying-down nystagmus in the lateralization of horizontal semicircular canal benign paroxysmal positional vertigo.

BACKGROUND: Horizontal canal benign paroxysmal positional vertigo is characterized by horizontal direction-changing nystagmus induced by lateral head turning in supine position. According to Ewald's second law, the direction of head turning that creates a stronger response represents the affected side in geotropic nystagmus and the healthy side in apogeotropic nystagmus. However, it may not always be possible to lateralize the involved ear only by comparing the intensity of the nystagmus. We studied the values of nystagmus induced by position change from sitting to supine in the lateralization of horizontal canal benign paroxysmal positional vertigo. METHODS: A retrospective study of 54 patients who had been diagnosed as having horizontal canal benign paroxysmal positional vertigo at the Dizziness Clinic of Seoul National University Bundang Hospital from May 2003 to February 2004 was performed. The directions of the nystagmus induced by lying down were compared with those determined by Ewald's second law. RESULTS: Of the 54 patients, 32 (20 apogeotropic and 12 geotropic) showed horizontal nystagmus induced by lying down. The nystagmus tended to be ipsilesional in apogeotropic patients (80%) and contralesional in their geotropic counterparts (75%). CONCLUSION: In horizontal canal benign paroxysmal positional vertigo, lying-down nystagmus mostly beats toward the involved ear in the apogeotropic type and directs to the healthy ear in the geotropic type. The direction of lying-down nystagmus may help lateralizing the involved ear in horizontal canal benign paroxysmal positional vertigo.     

水平半规管良性阵发性位置性眩晕的诊断

目的探讨水平半规管良性阵发性位置性眩晕（BPPV）的诊断。方法自2003年1月至2006年9月，本眩晕中心共确诊为水平半规管BPPV（HSC BPPV）患者46例。诊断依据为典型的病史及用红外视频眼震电图仪记录患者在Dix—Hallpike试验和滚转试验中的眼震结果，并排除其他疾病。研究HSC BPPV的眼震特点。结果441例诊断为BPPV患者中，46例（10．43％）为水平半规管BPPV。其中38例（82．61％）为单侧病变，5例（10．87％）患者合并同侧后半规管病变，3例（6．52％）为双侧病变。35例患者通过两种试验诱发出水平眼震，11例患者仅通过滚转试验诱发出水平眼震。25例患者眼震方向向地，13例患者眼震方向背地，3例患者眼震方向不固定，5例患者各种手法诱发出同一方向的眼震。29例患者在双侧手法中出现眼震，17例患者在一侧手法中出现眼震。结论HSC BPPV眼震为完全水平性且多为快相向地。通常受累耳在双侧手法中均可出现眼震，以向患侧为重。一侧水平半规管和后半规管可同时受累。滚转试验在HSC BPPV检查中比Dix—Hallpike试验更加敏感。Dix—Hallpike试验结合滚转试验可使更多的HSCBPPV患者得到确诊．     

Differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV)

This article presents an approach to differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV). Such an approach is essential because of the difference in intervention between the two disorders in question. Results from evaluation of the case study presented here revealed a persistent ageotropic positional nystagmus consistent with MPV or a cupulolithiasis variant of HC-BPPV. The patient was treated with liberatory maneuvers to remove possible otoconial debris from the horizontal canal in an attempt, in turn, to provide further diagnostic information. There was no change in symptoms following treatment for HC-BPPV. This case was diagnosed subsequently as MPV, and the patient was referred for medical intervention. Treatment has been successful for 22 months. Incorporation of HC-BPPV treatment, therefore, may provide useful information in the differential diagnosis of MPV and the cupulolithiasis variant of HC-BPPV.     

Differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV)

This article presents an approach to differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV). Such an approach is essential because of the difference in intervention between the two disorders in question. Results from evaluation of the case study presented here revealed a persistent ageotropic positional nystagmus consistent with MPV or a cupulolithiasis variant of HC-BPPV. The patient was treated with liberatory maneuvers to remove possible otoconial debris from the horizontal canal in an attempt, in turn, to provide further diagnostic information. There was no change in symptoms following treatment for HC-BPPV. This case was diagnosed subsequently as MPV, and the patient was referred for medical intervention. Treatment has been successful for 22 months. Incorporation of HC-BPPV treatment, therefore, may provide useful information in the differential diagnosis of MPV and the cupulolithiasis variant of HC-BPPV.     

Model experiment of benign paroxysmal positional vertigo mechanism using the whole membranous labyrinth

Whole membranous labyrinths of bullfrogs were used in order to replicate the human vestibule. The posterior semicircular canals (PSCs) were exposed, leaving the remaining membranous labyrinth encapsulated in the otic capsule. Vibration was applied to the surface of the bony capsule using a conventional surgical drill in order to dislodge the otoconia from the utricle. The position of the preparation was controlled so that the dislodged otoconia were attached to the cupular surface. This was regarded as a cupulolithiasis model. The action potentials changed instantaneously according to the gravitational force on the cupula. When the otoconia were dislodged and held within the PSC lumen, the position of the whole preparation was changed so that the otoconia moved back and forth within the canal lumen. This is a model of canalolithiasis. The action potentials changed in combination with the otoconial movement after a latent period. Both cupulolithiasis and canalolithasis are potentially valid mechanisms of benign paroxysmal positional vertigo (BPPV). However, canalolithiasis is the most likely mechanism of BPPV, which is usually characterized by nystagmus of short duration and long latency. A vibratory stimulus was able to detach the otoconia from the utricle, suggesting that mechanical insult could be a possible etiology of BPPV.     

3D analysis of benign positional nystagmus due to cupulolithiasis in posterior semicircular canal

Conclusions: The characteristic of both the vertical-torsional positional nystagmus with long time constant and its disappearance at the neutral head position could diagnose cupulolithiasis in posterior semicircular canal (PSCC) in the eight patients with the PSCC type of benign paroxysmal positional vertigo (P-BPPV). Objective: The aim of the study was to diagnose cupulolithiasis in patients with P-BPPV. Patients and methods: We used three-dimensional rotation axis analysis of nystagmus of the vertical-torsional positional nystagmus in 111 patients with P-BPPV and evaluated its time constant. We then examined whether the vertical-torsional positional nystagmus with long time constant disappeared at the neutral head position where the axis of the heavy cupula of the affected PSCC is aligned with gravity. Results: The first parameter showed a wide variation that could be divided into two groups: one lasting more than 40 s in 8 patients and another below 20 s in 103 patients. Since the time constant of the positional nystagmus induced by cupulolithiasis was much longer than that induced by canalolithiasis, this finding suggests that cupulolithiasis in the PSCC induced the vertical-torsional positional nystagmus with a long time constant in the group of eight patients. The vertical-torsional positional nystagmus disappeared in these patients at the neutral head position, where the axis of the cupula of affected PSCC aligned with gravity.