The Laryngoscope C 2014 The American Laryngological, V

Rhinological and Otological Society, Inc.

Efficacy of Computer-Controlled Repositioning Procedure for Benign Paroxysmal Positional Vertigo Xizheng Shan, MD; Xin Peng, MD; Entong Wang, MD, PhD Objectives/Hypothesis: To evaluate the short-term efficacy of the computer-controlled canalith repositioning procedure (CRP) for treatment of posterior canal benign paroxysmal positional vertigo (BPPV) compared with the current standard CRP. Study Design: Prospective case series. Methods: One hundred thirty-two patients diagnosed as having idiopathic posterior canal BPPV, with an age range of 28 to 86 years (mean 56 years), 47 men and 85 women, were treated with computer-controlled CRP mimicking the Epley maneuver. Resolution of vertigo and nystagmus on the Dix-Hallpike test at 1-week follow-up after treatment was the main outcome measure to assess the efficacy of treatment. Results: At 1-week follow-up after treatment with computer-controlled CRP, 108 (81.8%) of 132 patients had complete resolution of vertigo and nystagmus, nine (6.8%) had resolution of vertigo but presence of nystagmus, and 15 (11.4%) had provoked vertigo and nystagmus on the Dix-Hallpike test. The 81.8% success rate was comparable to those who received current standard CRP treatment in randomized controlled trials at about 80%. No significant adverse effects or complications occurred in the patients treated with computer-controlled CRP, aside from two patients (1.5%) with conversion into lateral canal BPPV. Conclusions: Computer-controlled CRP is effective for the treatment of posterior canal BPPV, with a success rate similar to those treated with the Epley maneuver, and is safe and easy to perform on patients. Key Words: Benign paroxysmal positional vertigo, posterior semicircular canal, computer-controlled canalith repositioning procedure, Epley maneuver, Dix-Hallpike test. Level of Evidence: 4 Laryngoscope, 00:000–000, 2014

INTRODUCTION Benign paroxysmal positional vertigo (BPPV) is a common vestibular disorder characterized by repeated episodes of positional vertigo produced by changes in head position, with a lifetime prevalence of 2.4% in the general population.1,2 Posterior canal BPPV (PC-BPPV) accounts for about 90% of BPPV cases.3,4 Although BPPV is a self-limiting disease with a favorable prognosis,5,6 persistent untreated BPPV may impact function, health, and the quality of life of patients, and also may leave patients, especially the elderly, with a high risk of falls.7,8 Therefore, patients can benefit from prompt treatment of BPPV.9 Although the etiology and pathophysiology of BPPV have been not fully understood, canalolithiasis is widely accepted as a main mechanism underlying BPPV.3 It is

From the Department of Otolaryngology–Head and Neck Surgery (X.S., X.P., E.W.), General Hospital of Chinese People’s Armed Police Forces, Beijing, China; and the Department of Otolaryngology–Head and Neck Surgery (E.W.), Air Force General Hospital, Beijing, China. Editor’s Note: This Manuscript was accepted for publication September 15, 2014. The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Entong Wang, MD, Department of Otolaryngology–Head and Neck Surgery, Air Force General Hospital, 30 Fucheng Road, Beijing 100142, China. E-mail: [email protected] DOI: 10.1002/lary.24961

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believed that BPPV occurs when otoconia detach from the macula of the utricle and enter the semicircular canal, and the movement of free-floating canalith particles in the semicircular canal results in vertigo attacks accompanied by nystagmus.3,10,11 Various canalith repositioning procedures (CRPs), which aim at moving the free-floating particles in the semicircular canal back into the utricle to relieve the vertigo symptom, have been used for the treatment of BPPV.1,10–12 The Epley maneuver (EM) as a CRP was first described by Epley in 1992.10 This maneuver has been used regularly to treat BPPV, showing good efficacy in the treatment of PCBPPV, and success rates of more than 80% have been reported in many randomized controlled trials (RCTs).10,13–15 EM also is considered to be one of the standard treatments for PC-BPPV and is recommended as the first-line treatment of PC-BPPV in the current clinical practice guidelines of the American Academy of Otolaryngology–Head and Neck Surgery1 and the American Academy of Neurology.12 However, the use of EM is limited in some patients, such as those with physical motion limitations and obesity, and especially the elderly.1,16 Some therapeutic devices have been developed to treat BPPV with promising treatment outcomes.17–21 In this prospective caseseries study, we evaluate the short-term efficacy of a computer-controlled CRP (CCRP) mimicking EM for the treatment of PC-BPPV. Shan et al: Computer-Controlled Repositioning Procedure

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Fig. 1. The diagnosis and therapy system for BPPV. This system mainly consists of a computer-controlled rotary chair (left) and a work station (right). Under control of the computer at the work station, the chair can be rotated on multiple planes at specific speeds at any degrees; thus, various diagnostic and repositioning maneuvers for BPPV can be performed by this system. Patient wears eye goggles connected with the camera that transfer the patient’s nystagmus signals wirelessly to the computer. The nystagmus video, dynamic nystagmus curve, semicircular canal orientation, and chair position during the Dix-Hallpike test or repositioning maneuver can be displayed in real time on the monitor, and nystagmus, if present, can be recorded, analyzed, and documented by the computer. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.]

MATERIALS AND METHODS Patients This study was conducted at the Department of Otolaryngology–Head Neck Surgery, General Hospital of Chinese People’s Armed Police Forces, Beijing, China from July 2010 to June 2012 and was approved by the hospital ethics committee. A total of 138 consecutive patients diagnosed as having PCBPPV were enrolled in the study. Informed consent was obtained from each patient. All patients underwent standard clinical examinations, diagnostic tests, and evaluation before treatment with CCRP. The inclusion criteria were as follows: history and symptoms compatible with idiopathic BPPV and diagnosis of unilateral PC-BPPV by the Dix-Hallpike test (DHT),1 BPPV occurring within 1 month before presentation, and BPPV not treated previously with CRP or vestibular suppressant medications. Patients were excluded when they had other variants of BPPV, other forms of peripheral or central vertigo, sudden sensorineural hearing loss, vestibular neuritis or labyrinthitis, Meniere’s disease, migraine, superior canal dehiscence syndrome, vestibular neuroma, severe central nervous system disorders, and severe cardiovascular diseases.

Diagnosis and Treatment of PC-BPPV PC-BPPV was diagnosed according to the criteria of the clinical practice guidelines of the American Academy of Otolaryngology–Head and Neck Surgery1 as patient-reported history of repeated episodes of vertigo with changes in head position and demonstrated characteristic vertigo and nystagmus provoked by the DHT. The performance of the DHT was reproduced by the diagnosis and therapy system for BPPV (Byrons Medical Science & Technique Inc., Jinan, China) (Fig. 1).22 All enrolled patients, according to their affected posterior canals identified by the DHT, were promptly treated with initial CCRP. At 24 hours after the initial CCRP, the patients who still presented with positional

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vertigo were given a second CCRP. The CCRP, which mimicked a standard EM as described in two guidelines,1,12 was also performed by the diagnosis and therapy system for BPPV (Fig. 1). In the study, all movements of the patients during the mimicked DHT or EM were performed at 90 per second. Any adverse effects or complications, if present, were recorded, and the patients were promptly treated. No medication was routinely administered before or after CCRP. No postural restrictions after CCRP were advised to the patients, because evidence-based studies have shown postural restrictions after CRP do not show significant benefits.23,24

Follow-up and Main Outcome Measures Patients were followed up at 1 week after initial or second CCRP to assess the resolution of vertigo and nystagmus on the DHT. The resolution of vertigo alone or both vertigo and nystagmus on the DHT were used as the main outcome measures to evaluate the effectiveness of CCRP for treatment of PC-BPPV. When absent of both provoked vertigo and nystagmus on the DHT, the patient was considered as having complete resolution of PC-BPPV. When a patient exhibited canal conversion after the initial or second CCRP, the patient would undergo further treatment with corresponding CRP based on the affected canal, but the patient, even with a successful treatment outcome in previous CCRP for PC-BPPV, or in following CRP for other types of BPPV, was not included in the efficacy analysis of CCRP for PC-BPPV. For the CCRP patients who failed at 1-week follow-up, they would be followed up further, reevaluated, and given individual treatments. Subsequent treatment results were not included in the analysis for short-term efficacy of CCRP in this study.

RESULTS A total of 138 patients, diagnosed as having unilateral PC-BPPV and treated with CCRP, were initially Shan et al: Computer-Controlled Repositioning Procedure

enrolled in this study. Three patients were lost for follow-up, one patient was excluded due to sudden sensorineural hearing loss, and two patients were excluded due to the occurrence of canal conversion during CCRP. Thus, 132 patients were included in the analysis for evaluating the short-term efficacy of CCRP. The 132 patients were aged from 28 to 86 years (56.1 6 9.2 years), and among them 85 (64.4%) were female and 47 (35.6%) were male, with a female/male ratio of 1.81. The duration of BPPV before presentation was 1 to 30 days (13.8 6 8.7 days), with a median of 12 days. All 132 patients received initial CCRP, and at 24 hours after initial CCRP, 48 (36.4%) patients showed resolution of vertigo, whereas the other 84 (63.6%) patients still presented with positional vertigo and were given a second CCRP. An average of 1.64 CCRPs were applied to each patient by the 1-week follow-up. With the DHT at the 1-week follow-up after treatment with CCRP, three treatment outcomes were obtained: 108 (81.8%) of 132 patients had a complete resolution (no presence of vertigo or nystagmus), nine (6.8%)patients had subclinical BPPV (absence of vertigo but presence of nystagmus), and 15 patients (11.4) were considered as having treatment failure (presence of both vertigo and nystagmus). When the resolution of vertigo was the main outcome measure, according to absence or presence of provoked vertigo regardless of nystagmus on the DHT, a success rate of 88.6% (117/132) was obtained at 1-week follow-up. If the presence of objective nystagmus on the DHT was showed, whether or not vertigo was present, a positive nystagmus rate of 18.2% (24/132) was achieved at the 1-week follow-up. CCRP was tolerated well by all patients, and no serious side effects from the use of CCRP were found, aside from discomfort and transient nausea reported in several patients. Two patients (1.5%) were found with canal conversion or canal switch to lateral canal; one occurred after initial CCRP and the other after the second CCRP. They were treated successfully by barbecue roll maneuver with resolution of symptoms subsequently. None of the 132 patients experienced conversion to superior canal BPPV during CCRP.

DISCUSSION EM is a highly effective treatment for PC-BPPV, which is supported by evidence-based clinical practice guidelines,1,12 systematic reviews, and meta-analyses.9,25–29 However, some patients are difficult to treat with classic manual EM. In recent years, several therapeutic repositioning devices have been developed to treat BPPV, and some studies have shown that the devices can successfully treat BPPV including difficult-to-treat BPPV.17–22 Lempert et al.’s study showed that seven (63.6%) of 11 patients with PC-BPPV had resolution of vertigo symptoms after EM was performed with a threedimensional flight simulator.17 In the study of Nakayama and Epley, a power-driven multiaxial repositioning chair was used for treatment of several BPPV variants, and good treatment outcomes were showed in their study.18 Li and Epley also used the multiaxial positioning device to Laryngoscope 00: Month 2014

treat PC-BPPV using a 360 maneuver, with a good subjective improvement rate (90%) after one treatment and good resolution rate (97%) of both vertigo and nystagmus after a maximum of three treatment sessions in 31 patients, including in the elderly over 90 years old.19 Shan et al. used a similar positioning device to treat BPPV, with promising treatment outcomes.20 Recently, a report showed that a 96-year-old patient afflicted with PC-BPPV was cured successfully by EM performed with a motorized turntable.21 The diagnosis and therapy system for BPPV used in the present study has been used in our clinic since 2009, showing good efficacy for the diagnosis and treatment of BPPV.22 In the present study, we evaluated the short-term efficacy of CCRP for the treatment of PC-BPPV. In the short term, typically at 1 week, CRP is very effective at providing symptom resolution for PC-BPPV.1 It is thought that the absence of vertigo may be the best indicator of success for CRP, 9,30 and many trials also report the conversion from positive to negative DHT after EM as a secondary outcome,9 similar to reported rates of symptom resolution.26 Thus, the resolution of vertigo or nystagmus on the DHT may be evaluated separately due to the possible presence of subclinical BPPV.1,30,31 Our study showed that 117 (88.6%) of 132 patients with idiopathic PC-BPPV had resolution of vertigo, and 108 (81.8%) patients had resolution of both vertigo and nystagmus on the DHT at the 1week follow-up after CCRP. CCRP may allow us to obtain a good success rate similar to those received by EM in most studies. A conversion rate of 81.8% to a negative DHT may also be comparable to the rates of 66% to 89% reported in an RCT.26 Another RCT showed that 80.5% (33/41) of EM-treated patients with unilateral idiopathic PC-BPPV had resolution of both vertigo and nystagmus on the DHT at day 7 after EM.14 In another RCT, the resolution of both vertigo and nystagmus was obtained in 86.4% (19/22) of patients with PC-BPPV on the DHT at 1 week after EM.13 Our study indicates that CCRP may be comparable to EM in therapeutic efficiency. Studies suggest that a few BPPV patients may demonstrate so-called subclinical BPPV after CRP, or absence of provoked vertigo but presence of nystagmus on the DHT.1,30,32,33 In our study, nine (6.8%) of the 132 patients presented with subclinical PC-BPPV by 1-week follow-up on the DHT. In addition, BPPV as a self-limiting disorder may resolve spontaneously.1 However, a previous study showed 30% of patients with PC-BPPV demonstrated the spontaneous disappearance of vertigo within 7 days, with an average of 39 6 47 days from the onset to remission of the vertigo,5 and a recent RCT showed that only eight (36%) patients of 22 sham-treated PC-BPPV patients with duration of at least 1 month demonstrated resolution of BPPV on the DHT at 1 month after treatment.15 Recently, a systematic review also showed that based on the analysis of pooled data, only six (8%) of 77 patients and 34 (36%) of 94 patients obtained spontaneous resolution of vertigo at 1-week and at 1 month, respectively, after watchful waiting.9 Thus, the resolution rate (88.6%) of vertigo symptoms at 1 week after CCRP in our study could not be explained completely by the spontaneous resolution of vertigo. Shan et al: Computer-Controlled Repositioning Procedure

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With respect to adverse effects and complications, no serious side effects or complications were found in the CCRP-treated patients aside from two patients (1.5%) with canal conversion to the lateral canal after CCRP. Canal conversion is a well-known phenomenon that occurs with CRP and is considered a complication of CRP.1,34–37 Canal conversion occurs in about 6% to 7% of PC-BPPV treated with EM.38,39 A previous study showed that among 85 patients with PC-BPPV treated by EM, three patients (3.5%) had the switch to the lateral canal and two patients (2.4%) to the anterior canal.38 In another study of 564 EM-treated patients with PC-BPPV, 13 (2.3%) patients had the switch to anterior canal BPPV.37 Recently, a study showed that of 44 patients with PC-BPPV treated by a single CRP, seven (16%) patients demonstrated canal conversion to the lateral canal.36 In our study, the incidence of canal conversion was low (1.5%), and no patient experienced conversion to the superior canal BPPV after CCRP. Compared with manual EM, CCRP offers some advantages. First, CCRP may completely mimic the performance of EM, and the patient may be moved on an accurate plane at specific speeds and degrees of rotation. All CCRP-treated patients receive a precise and uniformed repositioning maneuver. The nystagmus of patients, orientation of semicircular canals, and the position of the chair during CRP can be monitored in real time. Second, CCRP is a safe maneuver and has good applicability. In some patients with comorbid diseases, body movement limitations, or obesity, those conditions may render them unsuitable for manual EM, especially the elderly,1,16,40 but difficult-to-treat BPPV can be treated by CCRP. Third, the treatment of BPPV is involved in multiple clinical disciplines, and there are certain differences in EM performed by different physicians, whereas standardized CCRP is a repeatable and comparable maneuver. CCRP is easy to perform by a physician alone and takes less time.

CONCLUSION CCRP is an effective treatment for PC-BPPV and offers excellent short-term results, comparable to current standard repositioning maneuvers for PC-BPPV. Compared with manual EM, CCRP allows a physician to perform CRP alone, without needing help from an assistant, requires less time for the repositioning maneuver, and it is well tolerated by patients, especially the elderly. Our study supports the use of CCRP as a treatment choice for PC-BPPV, although manual EM still may be considered as a standard treatment.

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Efficacy of computer-controlled repositioning procedure for benign paroxysmal positional vertigo.

To evaluate the short-term efficacy of the computer-controlled canalith repositioning procedure (CRP) for treatment of posterior canal benign paroxysm...
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