在低場磁振造影中，由於磁共振訊號在低場下的訊雜比(Signal to Noise Ratio, SNR)較差，因此我們結合預先極化技術以及超導量子干涉元件(Superconducting quantum interference device, SQUID)以提高低場下磁共振系統的訊雜比。然超導量子干涉元件在低溫輸入線圈的調整上，受限於SQUID必須經過繁瑣的回溫動作才可以進行最佳化，使得在低溫中的輸入線圈較難做最佳化的動作。在本研究為了克服上述的困難，於測試前先模擬，計算最佳線圈匝數範圍後，再準備多組的輸入線圈，使得SQUID可在不需完全回溫的狀態下，進行線圈最佳化的測試，將系統核磁共振訊號的訊雜比提升16.2 %。此外預先極化技術，過去因開關電路可承受電流的限制僅為3.7 安培，故本研究將原電路改良使承載電流提升至7安培，使預極化磁場由684高斯大幅增加至1197高斯，使得核磁共振訊號的訊雜比也大幅提升了109 %。隨著以上的最佳化過程在三維造影解析度也進一步提升至2 mm × 2 mm × 2 mm。

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