Ⅱ. MATERIALS AND METHODS DEVELOPMENT OF A WEARABLE SYSTEM FOR DIAGNOSIS AND TREATMENT OF BENIGN PAROXYSMAL POSITIONAL VERTIGO 1 Interdisciplinary Program for Bioengineering, Graduate School, Seoul National University, Seoul, Korea 2 Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, Korea 3 Department of Biomedical Engineering, College of Medicine and Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University, Seoul, Korea Chiheon Kwon 1, Yunseo Ku 1, Joong-Woo Ahn 1, Myung-Whan Suh 2, *, and Hee Chan Kim 3, *  Dizziness caused by the otolith leaving from original position  The most common cause of dizziness (17% ~ 42%) [1]  BPPV Diagnosis : Occurrence of nystagmus depending on head direction  BPPV Treatment : Otolith repositioning exercise (e.g. Epley maneuver) Ⅲ. RESULTS Ⅳ. DISCUSSION AND CONCLUSION Ⅴ. REFERENCES [1] N. Bhattacharyya, R. F. Baugh, L. Orvidas, et al, “Clinical practice guideline: Benign paroxysmal positional vertigo,” Otolaryngol Head Neck Surg, vol. 139, pp. S47–S81, November [2] T. D. Fife, D. J. Iverson, T. Lempert, et al, “Practice Parameter: Therapies for benign paroxysmal positional vertigo (an evidence-based review) Report of the Quality Standards Subcommittee of the American Academy of Neurology”, Neurology, vol. 70, pp. 2067–74, May 2008 ACKNOWLEDGEMENTS This research was supported by BK21 Plus Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education (grant numbers 22A ). Ⅰ. INTRODUCTION A. Benign Paroxysmal Positional Vertigo (BPPV) B. Current Issue  Despite of high relapse rate of BPPV, it can be treated only at hospital  The Epley maneuver is difficult to perform without the help of a physician C. Proposal A. System Description  Development of a wearable system for diagnosis and treatment of BPPV at home - Determines occurrence of BPPV using ENG (Electro-Nystagmogram) signal - Provides sound guided instructions for the BPPV treatment - Provides real-time performance feedback through head motion tracking using accelerometer, gyro, and magnetometer C. Epley Maneuver Guiding System A. Validation of the ENG measurement system B. Effectiveness of Epley Maneuver Guiding system  The ratio of slopes per eye motion determines the direction of ENG  ENG signal of 10 subjects were tested for algorithm validation  Developed a wearable system which can measure ENG signal and head motion tracking  Electrode / Circuit integration and system miniaturizing for future work  System validation in BPPV patients in the future  Size : x 60 mm, ‘Behind The Ear’ Type System  The result shows that proposed system perform s better than existing handout system.  9 people tested for validation of Epley Maneuver Guiding System (Statistical Analysis Method : Wilcoxon Signed Rank Test) Fig.1 System Block Diagram Fig.3 Developed System Fig.4 Distinguishing a recorded ENG from the left/right ENG (a) Measured ENG Signal, (b) detection method for ENG direction  Performance of ENG Direction decision algorithm - Sensitivity : 1.00, Specificity : 0.85 Table 1 Comparison of accuracies for each step with or without the guide B. ENG direction detection algorithm  ENG Signal : 1mV amplitude, 0.1~50Hz bandwidth  Analog Frond End Design : 50Hz low-pass filter, Gain : 200V/V STEP 1 STEP 2 STEP 3 STEP 4 Fig.2 Procedure of Epley Maneuver (a)(b)