Comparative Study on the Roles of the Number of Accelerations and Rotation Angle in the Treatment Maneuvers for Posterior Semicircular Canal Benign Paroxysmal Positional Vertigo

Adding Kinetic Energy Does Not Further Improve Treatment Outcomes With a Mechanical Reposition Chair: A Randomized Controlled Trial

OBJECTIVE

To test if the addition of abrupt deaccelerations (kinetic energy) during treatment with a mechanical repositional chair (MRC) provides improved treatment efficacy with treatment of posterior benign paroxysmal positional vertigo (BPPV).

STUDY DESIGN

Randomized two-armed parallel open-labeled clinical trial.

SETTING

Tertiary referral center.

PATIENTS

Seventy patients diagnosed with posterior canalolithiasis BPPV were included.

INTERVENTIONS

All patients underwent diagnostics and treatment with an MRC. Patients were randomized to either a traditional Epley maneuver or a potentiated version of the Epley maneuver where kinetic energy was applied in five positions with 45-degree turns between each step.

MAIN OUTCOME MEASURES

Primary endpoint was the number of treatments needed before complete resolution of both subjective symptoms and objective signs of BPPV within the semicircular canal of interest. Secondary endpoints included the following: 1) number of patients requiring more than 10 treatments, 2) length of treatment in days before treatment(s) were successful, and 3) changes in total Dizziness Handicap Inventory scores before and after treatment.

RESULTS

No significant difference in the number of required treatments between the two treatment arms was found. Approximately three of four subjects were cured after two repositional maneuvers regardless of type of treatment. An equal length of treatment was seen with both groups, and the Dizziness Handicap Inventory scores were significantly lowered after treatment with no significant differences between the two types of treatment.

CONCLUSIONS

Both the traditional and the potentiated Epley maneuver are efficient in treatment of canalolithiasis of the posterior semicircular canals with MRC. Addition of kinetic energy with this subgroup of BPPV patients does not seem to add further efficacy to the treatment.

Canal switch in benign paroxysmal positional vertigo: Clinical characteristics and possible mechanisms

BACKGROUND

Canal switch-benign paroxysmal positional vertigo (CS-BPPV) refers to the phenomenon in which otolith particles move from one canal to another (on the ipsilateral side) during or after canalith repositioning procedure (CRP). However, the clinical characteristics of CS-BPPV and the underlying pathological mechanisms remain unclear. In this study, we investigated the incidence of canal switch (CS) for the different semicircular canals in benign paroxysmal positional vertigo (BPPV), examined nystagmus characteristics, and explored the underlying mechanisms.

METHODS

Clinical data for 1,099 patients with single-canal BPPV were collected and retrospectively analyzed. The incidences of CS in the different types of BPPV were analyzed. Patients were divided into CS-BPPV and non-CS (NCS)-BPPV groups according to whether they exhibited CS after CRP. The baseline characteristics and nystagmus characteristics of patients were compared between the two groups.

RESULTS

Patients with BPPV who developed or did not develop CS accounted for 4.6% (51/1,099) and 95.4% (1,048/1,099), respectively, of the patients included in the study. There were no statistically significant differences between the two groups in terms of sex, age, side of the canals involved, hypertension, or diabetes. CS was observed in 3.7% (25/677) of patients with PC-BPPV, including conversion between posterior canal (PC) and horizontal canal (HC) (1.6%, 11/677), and between PC and anterior canal (AC) (2.1%, 14/677). CS was observed in 5.2% (17/327) of patients with HC-BPPV, including from HC to PC (4.3%, 14/327), and from HC to AC (0.9%, 3/327). CS was found in 9.5% (9/95) of patients with AC-BPPV, including from AC to PC (8.4%, 8/95), and from AC to HC (1.1%, 1/95). The intensity of nystagmus was significantly greater in the CS-BPPV group compared with that in the NCS-BPPV group [24.00 (11-39) vs. 12.00 (7-24), P < 0.001]. Furthermore, the incidence of direction-reversing nystagmus was significantly higher in the CS-BPPV group than in the NCS-BPPV group [31.4% (16/51) vs. 4.3% (45/1,048), P < 0.001].

CONCLUSIONS

CS in BPPV is uncommon. Patients with AC-BPPV are more likely to develop CS, followed by patients with HC-BPPV and PC-BPPV. The occurrence of CS-BPPV may be related to the anatomical structure of the semicircular canals. When the canals contain large/heavy accumulations of otolith particles, CS may be more common during re-examination after CRP.

Study of the biomechanical mechanisms of benign paroxysmal positional vertigo

Abstract. From a biomechanical point of view, the process of Benign paroxysmal positional vertigo (BPPV) includes 2 fluid¯solid coupling effects: the interaction between particles and endolymph and the interaction between endolymph and cupula. The interaction between the canaliths and the wall would affect the coupling effects. This study aimed to investigate the entire process of cupula motion caused by canaliths motion and the influence of canalith particles composition. A biomechanical numerical model was established to simulate the canalith falling process and study the influence of canalith diameter, number, and initial falling position on cupula movement. Simultaneously, the relationship between cupula displacement and the nystagmus signal was analyzed in BPPV patients. The results revealed that the particle velocity was proportional to the particle diameter. The pressure difference between the two sides of the cupula was directly proportional to the canalith diameter and number. The degree of vertigo was positively related to the slow angular velocity of the nystagmus and, therefore, reflected canalith number and diameter. The BPPV latent period and vertigo duration were inversely related to particle diameter. Thus, the number of particles, particle radius, and initial falling position affected cupula movement, which was reflected in the nystagmus.

Efficacy of combined canalith-repositioning procedure and supine to prolonged lateral position in treating posterior canal benign paroxysmal positional vertigo

OBJECTIVES

Posterior benign paroxysmal positional vertigo (p-BPPV) is the most common type of BPPV, and canalith-repositioning procedure (CRP) is frequently applied for treatment. Supine to prolonged lateral position (SPLP), a simple home-based maneuver, can be performed for treatment of p-BPPV. The purpose of this study was to investigate whether combination of CRP and SPLP could be more effective in symptom alleviation compared with CRP alone and reduce times of repeated CRP for patients with p-BBPV.

METHODS

A retrospective chart review enrolled 96 patients diagnosed with primary p-BPPV. Of these patients, 64 patients were included in the CRP group and 32 patients, in the CRP+SPLP group. The outcome was determined according to days required to reach negative result in Dix-Hallpike test, duration of vertigo and dizziness following the first repositioning procedure, and times of CRP performed to reach resolution of p-BPPV.

RESULTS

Of patients in the CRP and CRP+SPLP groups, 38% and 16% received CRP at least twice to reach resolution, respectively (P = 0.034). Patients in the CRP group and CRP+SPLP group spent an average of 9.8 ± 6.1 days and 7.9 ± 3.4 days, respectively reaching a negative result in Dix-Hallpike test (P = 0.050). In terms of duration for relieving vertigo and dizziness, the CRP+SPLP group achieved symptom relief with shorter duration (P = 0.036 and P = 0.025, respectively).

CONCLUSION

Compared with CRP alone, combination of CRP and SPLP improved the therapeutic effectiveness and shortened the duration of suffering from vertigo and dizziness in patients with p-BPPV.

Treatment of horizontal canal BPPV-a randomized sham-controlled trial comparing two therapeutic maneuvers of different speeds

OBJECTIVES

To compare the effect of a high-speed barbecue maneuver with the modified Lempert maneuver and sham in patients with benign paroxysmal positional vertigo (BPPV) of the horizontal canal.

METHODS

Randomized sham-controlled, single blinded multicenter clinical trial in two university hospitals investigating consecutive patients with horizontal canal BPPV.Patients were randomly assigned to high-speed barbecue (HSB), modified Lempert maneuver (ML), or sham maneuver (SM). All treatments were performed in a biaxial rotational chair with weekly follow-up to a maximum of three treatment sessions. The final follow-up was 3 months after the last treatment.

RESULTS

Primary outcome: 2-week recovery rate per protocol. Secondary outcome: Cumulative recovery rate and Dizziness Handicap Inventory (DHI) scores after 3 months per protocol (HSB and ML) and intention to treat (all groups).Fifty-four patients were analyzed after 2 weeks (HSB = 17; ML = 20; SM = 17). Two-week recovery rate was 14/17 after HSB, 11/20 after ML, and 4/17 after SM, with significantly better recovery in HSB [OR 15.17, 95% CI (1.85, 124.63), P = .001] using sham as base level. Recovery rate after 3 months was 15/17 after HSB and 15/19 after ML. Cumulative recovery rate showed no significant differences between the two treatment groups [95% CI (0.30, 13.14), P = .46] in cure rate DHI [95% CI (-16.56, 15.02), P = .92]. No unexpected adverse events were observed.

CONCLUSION

Velocity change in horizontal canal BPPV treatment gives a faster initial recovery. Rapid recovery could reduce the disease burden.

TRIAL REGISTRATION

Clinicaltrials.gov. Identifier: NCT01905800.

LEVEL OF EVIDENCE

1b.