非接觸式生物組織電導率成像系統

The Contactless Imaging System for the Conductivity of Biological Tissues

蔡育廷(Yu-Ting Tsai)

指導教授 ： 鍾鴻源

國立中央大學/資訊電機學院/電機工程學系/碩士(2007年)

摘要

自從生物組織電導率影像被發表以來，電導率影像被視為一種非侵入式監測、可長時間監測、無輻射性傷害、具攜帶性以及成本低廉的醫學影像技術。本論文設計並製作的高性能非接觸式生物組織電導率成像系統利用磁感應原理以非接觸式的方式來成像，非接觸式電導率成像具有成像機構簡單、高安全性、高可靠性…等優點。成像系統包含非接觸式電導率感測器、成像平台、訊號產生器、鎖相放大器以及資料擷取/控制界面卡。在實驗中，吾人以靈敏度與空間解析度兩項指標來評估感測器性能，並對多種生物組織進行一維空間剖面掃描以及二維空間成像來評估系統實用性。實驗結果顯示本系統之感測器具有高靈敏度與高空間解析度，而且二維空間的生物組織電導率成像結果，可以成功的辨識生物組織中電導率相異的部分，比起國內外相關研究的成像結果均有所提升。最後，本論文提出以可重組態儀器架構將本成像系統整合成可獨立運作的單一系統，降低各個分散儀器間接線過長與過多所產生的雜訊以期提升成像品質，並且改善實驗操作之方便性以期縮短成像時間。整合後的成像系統除了驗證此架構之可行性外，也改善本系統之穩定性與操作性。

關鍵字

電導率 ； 磁感應 ； 生物影像 ； 轉向差動接收線圈 ； 可重組態儀器

並列摘要

Since the first biological conductivity image was proposed, the conductivity imaging has been regarded as a functional imaging technique in the medical field. The conductivity imaging provides many advantages in biomedical applications, such as non-invasion, long-term monitoring, radiation-free, portable, and lower cost. In this thesis, a high performance non-contact imaging system for the conductivity of biological tissues was proposed. The non-contact method has many advantages, such as simple mechanism, high safety, and reliability. The proposed imaging system includes contactless conductivity sensor, imaging platform, function generator, lock-in amplifier, and data acquisition/control card. The sensitivity and one-dimension spatial resolution was applied to evaluate the performance of the proposed sensor. The imaging results show the proposed sensor has high sensitivity and spatial resolution, which provides the feasibility of distinguishing the conductivity distribution on interesting region of biological tissues. In the end, the reconfigurable instrument scheme was proposed to improve the imaging system. The scheme which reduces noise resulted from wirings between instruments could improve the imaging quality and simplify the experimental procedures. The experiment results of modified imaging system show the improvement of the system stability and convenience.

並列關鍵字

biological imaging ； magnetic induction ； conductivity ； differential receiver coil alignment ； reconfigurable instrument

參考文獻

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