Objectives The aim of this study was to develop a filtering algorithm for raw nystagmus images and a diagnostic assistive algorithm using a principal component analysis (PCA) to distinguish the different types of benign paroxysmal positional vertigo (BPPV).
Methods Fifteen video clips of clinical data with typical nystagmus patterns of BPPV (13 cases) and with normal nystamgmus (two cases) were preprocessed when applied the thresholding, morphology operation, residual noise filtering, and center point extraction stages. We analyzed multiple data clusters in a single frame via a PCA; in addition, we statistically analyzed the horizontal and vertical components of the main vector among the multiple data clusters in the canalolithiasis of the lateral semicircular canal (LSCC) and the posterior semicircular canal (PSCC).
Results We obtained a clear imaginary pupil and data on the fast phases and slow phases after preprocessing the images. For a normal patient, a round shape of clustered dots was observed. Patients with LSCC showed an elongated horizontal shape, whereas patients with PSCC showed an oval shape at the (x, y) coordinates. The scalar values (mm) of the horizontal component of the main vector when performing a PCA between the LSCC- and PSCC-BPPV were substantially different (102.08±20.11 vs. 32.36±12.52 mm, respectively; p=0.0012). Additionally, the salar ratio of horizontal to vertical components in LSCC and PSCC exhibited a significant difference (16.11±10.74 mm vs. 2.61±1.07 mm, respectively; p=0.0023).
Conclusions The data of a white simulated imaginary pupil without any background noise can be a separate monitoring option, which can aid clinicians in determining the types of BPPV exhibited. Therefore, this analysis algorithm will provide assistive information for diagnosis of BPPV to clinicians.
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Development of An Algorithm for Slippage-Induced Motion Artifacts Reduction in Video-Nystagmography Yerin Lee, Young Joon Seo, Sejung Yang Research in Vestibular Science.2022; 21(4): 104. CrossRef
Objectives This study was performed to investigate the correlation between subjective residual dizziness and objective postural imbalance after successful canalith repositioning procedure (CRP) in benign paroxysmal positional vertigo (BPPV) by using questionnaires and modified Clinical Test of Sensory Integration and Balance (mCTSIB).
Methods A total of 31 patients with BPPV were included prospectively in the study. All included patients were successfully treated after initial CRP and their symptoms and nystagmus disappeared. Two weeks after CRP, all patients were asked to fill out the questionnaire including both Dizziness Handicap Inventory (DHI) and visual analog scale (VAS). We also conducted mCTSIB 2 weeks after CRP. We divided patients into two groups according to VAS: RD (residual dizziness) group, VAS>0; non-RD group, VAS=0. We compared age, number of CRP, rates associated with three semicircular canals, DHI score and mCTSIB results between two groups. In addition, we analyzed the correlation between DHI score and mCTSIB results.
Results There were no significant differences in age, number of CRP, and rates associated with three semicircular canals between the two groups. RD group showed significantly higher DHI score and abnormal mCTSIB results than the non-RD group (p<0.05). DHI score and the number of abnormal mCTSIB showed a statistically significant correlation.
Conclusions We demonstrated the correlation between DHI score and mCTSIB after successful CRP for BPPV. It also represents that subjective residual dizziness is correlated with objective postural imbalance even after successful CRP. Therefore, mCTSIB would be a useful test to evaluate both residual dizziness and postural imbalance after CRP in BPPV.
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Immediate Improvement in Subjective Visual Vertical and Disequilibrium Predicts Resolution of Benign Paroxysmal Positional Vertigo Following Single Canalith Repositioning Maneuver Christine C. Little, Zachary G. Schwam, Marc Campo, James Gurley, Bryan Hujsak, Maura K. Cosetti, Jennifer Kelly Otology & Neurotology Open.2022; 2(3): e014. CrossRef
Gait and Postural Control Characteristics among Individuals with Benign Paroxysmal Positional Vertigo: A Scoping Review Haziqah Nasruddin, Maria Justine, Haidzir Manaf Malaysian Journal of Medicine and Health Sciences.2022; 18(s15): 377. CrossRef
Objectives Benign paroxysmal positional vertigo (BPPV) is a potentially recurrent disease even after successful canalith repositioning maneuvers. However, the exact recurrence rate or any clinical factors affecting the recurrence of BPPV still need to be elucidated.
Methods We recruited patients diagnosed as BPPV in a tertiary hospital for 3 years. We retrospectively reviewed the clinical information of the patients including baseline demographics, comorbidities and predisposing factors through the electronic medical records. We performed a telephone survey or direct interview 3 to 6 years later from the initial diagnosis of BPPV was made. To determine the factors associated with the recurrence, we divided study population into two subgroups; ‘recurrence group’ vs. ‘recurrence-free group.’ Then, intergroup comparative analyses were performed.
Results Among 397 patients who were originally eligible for the study, we performed a telephone survey or direct interview in 289 patients (72.8%) to determine the recurrence of BPPV. The overall recurrence rate was 29.4% (85 of 289). Baseline demographics except female gender (p=0.014) were not different between subgroups. Neither clinical characteristics nor vascular comorbidities were associated with the recurrence. However, patients with low bone mineral density (BMD; T-score below ‒1, osteopenia/osteoporosis) showed significantly higher recurrence than those with normal BMD (40.6% vs. 0%, p=0.009).
Conclusions Female gender and low BMD (T-score below ‒1) were associated with the recurrence of BPPV in this study. Further researches in various clinical settings with larger sample size are warranted to identify the factors affecting the relapse of BPPV.