Canalolithiasis of the superior semicircular canal: an anomaly in benign paroxysmal vertigo

According to the canalolithiasis theory, benign paroxysmal vertigo (BPPV) is caused by gravity-dependent movements of otoconial debris that collects in the endolymph of the posterior semicircular canal. Other parts of the vestibular organ are rarely affected, and it is mainly the horizontal canal that is affected by this atypical form of BPPV. Canalolithiasis of the superior semicircular canal must be considered an anomaly because the superior semicircular canal is the highest point of the vestibular organ and debris normally cannot collect in this special location. Until now, BPPV of the superior canal has mainly been dealt with theoretically in the literature. The authors present three patients with canalolithiasis of the superior semicircular canal and offer direct proof of the condition using high-resolution 3D MRI.     

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.     

Anterior Canal benign paroxysmal positional Vertigo following surgical Management of superior canal dehiscence

Objective

Benign paroxysmal positional vertigo (BPPV) is a common post-surgical finding in patients managed for superior semicircular canal dehiscence (SSCD). The posterior semicircular canal has been reported as the involved canal in the majority of cases of post-surgical BPPV, with only two cases reported of lateral canal involvement. The objective of this report is to present a case in which an anterior semicircular canal BPPV response was identified in a patient following surgical management for SSCD.

Inkurabler und atypischer benigner paroxysmaler Lagerungsschwindel

Benign paroxysmal positional vertigo (BPPV) is the most frequent vestibular disorder and a most common cause of dizziness and vertigo. The modern canalolithiasis theory postulates the existence of free-floating dense otolithic particles in the endolymph of the posterior semicircular canal. The symptoms were exactly described by Dix and Hallpike; BPPV is normally a self-limited disease with spontaneous recovery. There is however a small number of patients who do not respond to any treatment or who present with otolithic vertigo which does not fit all Dix-Hallpike criteria (atypical BPPV). While BPPV in its typical appearance cannot be diagnosed with radiologic imaging, the authors succeeded in identifying structural changes in the vestibular organs of patients suffering from intractable or atypical BPPV using three-dimensional magnetic resonance imaging.     

Intractable and atypical benign paroxysmal vertigo. Pathological results of high-resolution three-dimensional MR-tomography of the vestibular organ

Benign paroxysmal positional vertigo (BPPV) is the most frequent vestibular disorder and a most common cause of dizziness and vertigo. The modern canalolithiasis theory postulates the existence of free-floating dense otolithic particles in the endolymph of the posterior semicircular canal. The symptoms were exactly described by Dix and Hallpike; BPPV is normally a self-limited disease with spontaneous recovery. There is however a small number of patients who do not respond to any treatment or who present with otolithic vertigo which does not fit all Dix-Hallpike criteria (atypical BPPV). While BPPV in its typical appearance cannot be diagnosed with radiologic imaging, the authors succeeded in identifying structural changes in the vestibular organs of patients suffering from intractable or atypical BPPV using three-dimensional magnetic resonance imaging.     

Horizontal canal benign paroxysmal positional vertigo--its affected side and horizontal semicircular canal function

We report horizontal canal BPPV (HC-BPPV) targeting its pathophysiology, the affected side, and the function of the horizontal semicircular canal, together with a review of the literature. Subjects were 13 patients with HC-BPPV visiting our vertigo outpatient clinic at Nara medical university hospital and a related hospital in the 2.5 years from January 2000 to June 2002. Subjects were classified into 7 with canalolithiasis and 6 patients of cupulolithiasis after a neurotological examination. CP was positive in 54% of all patients, 71% of those with canalolithiasis, and 33% of those with cupulolithiasis. To determine the affected side in HC-BPPV, we used the affected side by using the law of Ewald in canalolithaisis patients and the detection of a neutral diminishing nystagmus in cupulolithiasis patients. CP positive in caloric testing indicated insignificant dysfunction of the horizontal semicircular canal in canalolithiasis patients compared to that in cupulolithasis patients. The mechanism behind caloric nystagmus was thought to be a convection of endolymphatic fluid interrupted consequently by an otolith in the semicircular canal in canalolithiasis patients. In contrast, CP was positive in cupulolithiasis patients regarded as having no convection of endolymphatic fluid. The mechanism causing a difference in caloric test results between canalolithiasis and cupulolithiasis patients thus requires a larger patient population and further examination to be conclusive.     

“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 of the anterior semicircular canal: clinical aspects and treatment

OBJECTIVE: To describe the videonystagmographic characteristics and the treatment of the patients reached with a canalolithiasis or a cupulolithiasis of the anterior semicircular canal. MATERIAL AND METHOD: Retrospective study concerning patients treated for a Benign Paroxysmal Positional Vertigo (BPPV) of the anterior semicircular canal. Each patient after analysis under videonystagmoscopy (VNS) and under videonystagmography (VNG) was treated by maneuvers. RESULTS: On 462 observations of typical BPPV 6 cases of VPPB of the anterior semicircular canal were treated concerning 5 patients (1.3%). CONCLUSION: The BPPV of the anterior semicircular canal are rare. We modified our method of diagnosis, and our therapeutic techniques could be validated with the help of the two-dimensional videonystagmography.     

Diagnosis and management of benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is a common disorder of the vestibular labyrinth which should be suspected in all patients with a history of vertigo during changes of head position. The BPPV appears to be caused by free-floating debris in the posterior semicircular canal. The diagnosis is confirmed by eliciting characteristic symptoms during the Dix-Hallpike test. Although the BPPV usually is a self-limited disorder treatment with a specific bedside maneuver is effective and can shorten the duration of symptoms.     

Surgical management for benign paroxysmal positional vertigo of the superior semicircular canal

Benign paroxysmal positional vertigo of the superior semicircular canal is a rare form of BPPV. It accounts for 1% to 3% of cases. The characteristic nystagmus is positional, down‐beating, with a torsional component elicited by the Dix‐Hallpike maneuver. Symptoms of superior semicircular canal BPPV often resolve spontaneously; however, it can be refractory to repositioning maneuvers. Surgical management is described for posterior semicircular canal BPPV. To date, however, there is only one reported case of surgical management for superior semicircular canal BPPV. Here we show video documentation of positional, down‐beating nystagmus and describe a case of superior semicircular canal BPPV requiring canal occlusion with successful resolution of symptoms. Laryngoscope, 125:1965–1967, 2015     

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.     

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.     

Bone mineral density and serum 25-hydroxyvitamin D in subtypes of idiopathic benign paroxysmal positional vertigo

Although the etiology of benign paroxysmal positional vertigo (BPPV) is idiopathic in most cases, the association of osteoporosis or vitamin D deficiency with BPPV has attracted much interest recently. While it is generally accepted that osteoporosis or vitamin D deficiency is related to the occurrence and/or recurrence of BPPV, the difference in serum vitamin D level and bone mineral density (BMD) among different subtypes of BPPV has not been investigated. We aimed to compare T-score of BMD score and serum 25-hydroxyvitamin D level among idiopathic BPPV patients with a different subtype. This study included 117 consecutive patients with idiopathic BPPV (26 men and 91 women; mean age, 55 ± 11 years; age range, 25 to 78 years) who underwent blood sampling for serum 25-hydroxyvitamin D level measurement and bone mineral densitometry of the anterior-posterior lumbar spine and femur between April 2018 and February 2019. Among 117 patients, 49 were diagnosed with posterior semicircular canal (PSCC) BPPV, 24 were diagnosed with lateral semicircular canal (LSCC) canalolithiasis, and 44 were diagnosed with LSCC cupulolithiasis. The mean T-score of BMD was −1.5 ± 0.9 in PSCC BPPV, −1.5 ± 1.3 in LSCC canalolithiasis, and −1.5 ± 1.1 in LSCC cupulolithiasis, which was not significantly different (p = 0.998, One-way ANOVA test). The mean level of 25-hydroxyvitamin D was 22.5 ± 10.6 ng/ml in PSCC BPPV, 26.8 ± 16.0 ng/ml in LSCC canalolithiasis, and 25.4 ± 9.6 ng/ml in LSCC cupulolithiasis, which was not significantly different (p = 0.262, One-way ANOVA test). The proportion of osteoporosis/osteopenia or vitamin D deficiency/insufficiency did not show significant difference among idiopathic BPPV patients with different subtypes, and findings of this study indicate that either serum level of vitamin D or T-score of BMD is not a distinguishable characteristic among different subtypes of BPPV.     

Posterior semicircular canal occlusion for benign paroxysmal positional vertigo—CO2 laser-assisted technique: Preliminary results

Benign paroxysmal positional vertigo (BPPV) is a common vestibular end-organ disorder that in the majority of patients resolves with conservative management. In the occasional patient who has unremitting BPPV despite conservative treatment, posterior semicircular canal occlusion (PCO) may be effective in eliminating symptoms. In an attempt to minimize the risk of hearing loss, a modified procedure was developed that uses the CO₂ laser to shrink the membranous vestibular posterior semicircular canal prior to mechanically plugging the canal. Preliminary results of this CO₂ laser-assisted occlusion technique used in four patients are presented.     

Experimental study of speed-dependent positional nystagmus in benign paroxysmal positional vertigo

OBJECTIVE: One of the clinical characteristics of benign paroxysmal positional vertigo (BPPV) is that the more quickly the head position changes, the more severe the vertigo. This suggests that the velocity of the head change is critical in determining the occurrence and severity of vertigo. The aim of this study was to examine factors determining the symptoms of BPPV using models of canalolithiasis and cupulolithiasis. MATERIAL AND METHODS: Canalolithiasis and cupulolithiasis models were prepared using the bullfrog posterior semicircular canal (PSC). The ampullary nerve discharges were compared between quick and slow positional changes to examine factors determining the symptoms of BPPV. RESULTS: In the canalolithiasis model, the acceleration of the otoconia was greater for the quick positional change. This resulted in a greater discharge with a longer duration. With the slow positional change, the discharges were smaller and shorter. In the cupulolithiasis model, the discharges were sustained and their magnitude did not differ between the quick and slow positional changes. The canalolithiasis model influenced the magnitude of discharge of the PSC depending on the speed of the positional change. CONCLUSION: Canalolithiasis is the more likely mechanism of BPPV, which is characterized by various degrees of vertigo upon kinetic positional change.     

Particulate Matter in the Posterior Semicircular Canal

The pathoetiology of benign paroxysmal positional vertigo (BPPV) is controversial. Particulate matter within the posterior semicircular canal has been identified intraoperatively in patients with BPPV but has also been reported in non-BPPV patients at the time of translabyrinthine surgery (Parnes LS, McClure JA. Free-floating endolymphatic particles: a new operative finding during posterior semicircular canal occlusion. Laryngoscope 1992;102:988-92; Schuknecht HF, Ruby RRF. Cupulolithiasis. Adv Otorhinolaryngol 1973;20:434-43; Kveton JF, Kashgarian M. Particulate matter within the membranous labyrinth: pathologic or normal? Am J Otol 1994;15:173-6). The nature of the particulate matter remains unknown. The purpose of this study was to prospectively examine the posterior semicircular canal of patients with and without a clinical history of BPPV for the presence of particulate matter. Seventy-three patients without BPPV symptoms undergoing labyrinthine surgery (vestibular schwannoma excision or labyrinthectomy) and 26 patients with BPPV undergoing the posterior semicircular canal occlusion procedure were compared. Additionally, 70 archived temporal bones without a history of BPPV were examined microscopically for the presence of particulate matter within the lumen of the membranous labyrinth. No particles were observed intraoperatively in any of the 73 patients without a history of BPPV. Particulate matter was observed in 8 of 26 patients at the time of the posterior semicircular canal occlusion procedure for intractable BPPV. Of the 70 temporal bones examined, 31 did not show significant postmortem changes and also did not demonstrate cupulolithiasis or canalithiasis. Particulate matter from within the membranous posterior semicircular canal was removed from one patient at the time of posterior semicircular canal occlusion for intractable BPPV symptoms and was examined by scanning electron microscopy. The particulate matter appeared morphologically consistent with degenerating otoconia. These data show a statistically significant association between the presence of particles within the posterior semicircular canal in this study and the symptom complex of BPPV.     

突发性聋伴发良性阵发性位置性眩晕的临床特点及疗效观察

目的　探讨突发性聋伴发良性阵发性位置性眩晕（benign paroxysmal positional vertigo,BPPV）的临床特点,观察其疗效。方法　观察2012年10月～2014年6月耳 鼻咽喉科收治的36例突发性聋伴发BPPV发病情况,并与同期原发性BPPV患者40例及突发性聋不伴眩晕患者40例进行疗效比较。结果　伴发BPPV的36例突发性聋患者,受累半规管均与突发性聋发病侧一致,其中水平半规管BPPV 6例,占16.7%（6/36）;后半规管BPPV 27例,占75.0%（27/36）;混合管BPPV 3例,占8.3%（3/36）。36例患者出现BPPV的时间均在突发性聋发病后数小时至数天（＜10天）发生。突发性聋伴发BPPV组1次治愈率明显低于原发性BPPV组,但两种治疗方法的总治愈率均为100%。不伴眩晕突发性聋组的痊愈率、显效率及有效率均高于伴发BPPV组。结论　伴发于突发性聋的BPPV以后半规管多见,与原发性BPPV经耳石复位治疗后均可取得较好疗效。而不伴眩晕的突发性聋其疗效优于伴发BPPV的突发性聋。     

Experimental Study of Speed-dependent Positional Nystagmus in Benign Paroxysmal Positional Vertigo

Objective—One of the clinical characteristics of benign paroxysmal positional vertigo (BPPV) is that the more quickly the head position changes, the more severe the vertigo. This suggests that the velocity of the head change is critical in determining the occurrence and severity of vertigo. The aim of this study was to examine factors determining the symptoms of BPPV using models of canalolithiasis and cupulolithiasis. Material and Methods—Canalolithiasis and cupulolithiasis models were prepared using the bullfrog posterior semicircular canal (PSC). The ampullary nerve discharges were compared between quick and slow positional changes to examine factors determining the symptoms of BPPV. Results—In the canalolithiasis model, the acceleration of the otoconia was greater for the quick positional change. This resulted in a greater discharge with a longer duration. With the slow positional change, the discharges were smaller and shorter. In the cupulolithiasis model, the discharges were sustained and their magnitude did not differ between the quick and slow positional changes. The canalolithiasis model influenced the magnitude of discharge of the PSC depending on the speed of the positional change. Conclusions—Canalolithiasis is the more likely mechanism of BPPV, which is characterized by various degrees of vertigo upon kinetic positional change.     

Clinical features of paroxysmal positional vertigo presenting combined lesions.

Benign paroxysmal positional vertigo (BPPV) is one of the common vestibular disorders. Canalolithiasis is thought to be a likely lesion. A canalith repositioning procedure (CRP by Epley) generally yields good resolution of vertigo and nystagmus. The authors confirmed the efficacy of this procedure on typical BPPV of the posterior semicircular canal type. We designed a new procedure for BPPV of the lateral canal type, which also yielded satisfactory results. BPPV sometimes presents a nystagmus pattern, which suggests multiple lesions. We have seen eight cases of BPPV showing nystagmus that combines both the posterior and the lateral canal types. Combined CRP was performed on these cases, which again gave good clinical results. Other BPPV cases were associated with central lesions. We must be aware that BPPV may involve multiple canals and may be associated with central lesions.