前庭誘發肌性電位檢查之波形產生器

Abstract

由於維持身體平衡對於個人生活及日常活動是很關鍵的一部分，因此眩暈隨之產生的平衡障礙將嚴重影響患者的日常生活及心理狀態，同時也將帶給醫療保健系統巨大負擔。眩暈的症狀在臨床上極為常見，全球約有20 % ~ 30 %的人曾受到眩暈的影響，而其成因大多源自於周邊性的內耳前庭神經疾病。前庭系統為人體維持平衡的重要系統，其中負責感知頭部線性加速度的耳石器官可經由前庭誘發肌性電位檢查（Vestibular Evoked Myogenic Potential, VEMP）進行篩檢。近年來，因考量到人口老化速度急劇上升且眩暈症在老年人口發生率較高，因此為降低老年患者進行VEMP檢查的困難度，本研究期望能改善現今VEMP檢查僅能於醫院實行的缺點，提升VEMP檢查的便利性，使的VEMP檢查能讓醫師執行於偏鄉地區，甚至整合成為居家醫療的項目之一。本研究將著重於設計一波形產生器，以應用於利用骨導振動進行VEMP檢查時用以驅動振動器產生振動刺激之輸入訊號，此裝置所選用之元件及各部分電路配置皆以低功耗、體積小、重量輕為主要設計考量，如此所達成之可攜性及便利性將有利於醫院外環境所使用。另外，為達到足夠的電流以驅動振動器產生振動刺激，本研究所設計之波形產生器將連接至之前已開發完成之功率放大器，整體裝置可由單顆鋰電池進行供電，靜態電流僅2.75 mA且同時具有體積小、重量輕的特點，未來經過整合後，除了可提升攜帶之便利性外，同時亦將使得醫師能更加簡單的操作，進而有效改善VEMP檢查受限於醫療院所之環境的缺點。

Since maintaining body balance is a critical part of personal life and daily activities, the balance disorder caused by vertigo will seriously affect patients’ daily life and psychological state, and will also place a huge burden on the health care system. Vertigo is a extremely common clinical symptom, about 20% to 30% of people worldwide have been affected by vertigo, and most of its causes originate from peripheral inner ear vestibular nerve disease. The vestibular system is an important system for maintaining human body balance, and the otolith organ in the vestibular system, which is responsible for sensing linear acceleration of the head can be screened through the Vestibular Evoked Myogenic Potential(VEMP) examination. In recent years, taking into account the rapid increase in the aging of the population and the higher incidence of vertigo in the elderly population, in order to reduce the difficulty of performing VEMP examination for elderly patients, this study hopes to improve the shortcomings of current VEMP examination that can only be performed in hospitals, improve the convenience of VEMP examination and enable doctors to perform it in rural areas, and even integrate it into one of the medical home projects. This study will focus on the design of a pattern generator for the input signal used to drive the vibrator to generate vibration stimulation during VEMP examination using bone conducted vibration. The components used and the circuit configuration of this device were more about low power consumption, small size, and light weight. The portability and convenience achieved in this way will be beneficial to apply this device in environments outside the hospital. In addition, in order to supply sufficient current to drive the vibrator, the pattern generator designed will be connected to the power amplifier developed previously. The entire device can be powered by a single lithium battery, with the quiescent current of only 2.75 mA, and it also has the characteristic of small size and light weight. After integration, it will not only improve the portability, but also make it easier for doctors to operate it, and thereby effectively overcome the difficulty of VEMP examination that has to be restricted in the environment of medical institutions.