電阻抗斷層影像技術在肺部的即時或長時連續監測深具潛力，本研究應用電阻抗斷層影像來量化及分析肺部氣體的通氣分佈狀態。本研究探討三個部分：1、實驗設計，2、測量校正，和3、視覺化呈現。本研究在IRB同意與書面受試者同意書下收受三位正常人，實驗設計中擷取每位受試者在自主呼吸狀態下，五層胸廓截面之二維電阻抗斷層影像並同步使用肺量計取得口腔通氣量，其次將電阻抗影像內插影像，用以重建三維肺部立體模型。此外同步量測的肺流量訊號以內插方法將不同時間量測的電阻抗影像同步，作為影像時間對位參考指標。在測量校正部份則應用肺量計體積變化為量化標準，針對電阻抗影像與肺量計訊號進行回歸分析求得校正因子，再利用校正因子回推三維影像中體積變化並與肺量計測得的體積比較；從實驗結果得知，三維電阻抗影像誤差 小於10 %，反之二維電阻抗影像的誤差最大超過 100 %，且會因為肺區通氣程度而影響量化之線性程度。因此目前臨床應用的二維電阻抗影像較不易獲得肺部氣流在空間中的分佈資訊。三維電阻抗影像可提供更具臨床參考價值的肺部氣體分佈。

Electrical Impedance Tomography (EIT) is a potential technology for real-time or long-term use in continuous monitoring of the lungs. This study applies electrical impedance images to quantify and analyze the distribution of air in the lungs. There are three parts in this study: (1) Experimental design, (2) Measurement calibration, and (3) 3D visualization. In this study, three healthy subjects are recruited with IRB approval and informed consent. In the first part, five layers of thoracic sections are measured under spontaneous breathing for each subject. The impedance images and flows via mouth are both synchronously acquired. Then, the images are interpolated for three dimension reconstruction and the flow signals are also interpolated for registering to the images. In the measurement calibration, the flow measurement obtained from spirometer is used as gold standard for calibration using regression method. With the correction factors, the volume in impedance image may be quantified and compared. From the experimental results, the error may be smaller than 10 % in 3D measurement, and on the contrary greater than 100% in 2D measurement. Therefore, 2D EIT is not easy to quantify the air distribution of the lung perfusion in the current clinical application. 3D EIT has great potential to provide the lung air distribution.

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