多通道閉迴路癲癇偵測之低功率積體電路實現

Abstract

全球約有五千萬的人患有癲癇疾病，為第三大神經系統失調疾病。約有75%的病人可以透過藥物長期治療，或是利用外科手術切除患部而控制癲癇， 但仍然有25%的癲癇患者無法透過上述兩種方式成功治療。因癲癇是由大腦的不正常放電引起，可刺激腦部達到治療癲癇，並透過腦電圖進行臨床評估及癲癇偵測發作。早期利用腦部刺激開迴路控制器進行癲癇治療，但因準確率只有45%，為了提高準確率，近年提出的癲癇腦部刺激閉迴路控制器為創新及有效的替代方案。 在本團隊先前的研究中，已透過8051平台實現即時癲癇偵測與抑制系統。但為了降低整個系統的功率以及面積，在此篇研究中，先利用FPGA驗證演算法的準確率，再使用ASIC方式實現多重頻道低功率閉迴路癲癇偵測電路，具有多重頻道、低功率、低面積和即時運算判斷的特點。偵測癲癇的準確率可達到94.6%，在0.63-0.80s內偵測到癲癇啟動電刺激。利用台積電 0.18μm CMOS製程製作晶片，功率消耗可降低到114.4μW，比原先系統降低了99.5%。

Epilepsy is one of the most common neurological disorders, by which around 1% of the people in the world are affected. Unfortunately, 25% of the epilepsy patients cannot be treated sufficiently by antiepileptic drugs and epilepsy surgery. If seizures cannot be well controlled, the patients experience major limitations in their lives. In recent years, open-loop seizure controllers, such as vagus nerve and deep brain stimulation devices, have been proposed, but the effective rates of these devices are limited to 45%. In addition, low power and small hardware area are two important targets for implantable and portable devices. To overcome these issues, a real-time closed-loop seizure detection method is proposed. A multi-channel closed-loop epileptic seizure detector (MCESD) receives EEG signals of rats through ADC and delivers a stimulus at seizure. The seizure detection algorithm is realized by MCESD. The MCESD is implemented in a TSMC 0.18μm CMOS process. The seizure detection accuracy of device is above 94.6% from seizure detection algorithm with MCESD implementation, and the power of chip consumes 114.4μW.