國立臺灣大學電機工程學系暨研究所鍾孝文2006-07-252018-07-062006-07-252018-07-062005-07-31http://ntur.lib.ntu.edu.tw//handle/246246/8064本計畫第一年特定目標，係欲探討是 否FLAIR 技術在去除腦脊髓液的部份體積 效應之後，能夠協助達成更佳的白質神經 纖維追蹤。七位健康成人受試者（23~27 歲）經由五次反覆的造影過程，取得傳統 與FLAIR 的擴散張量影像，之後再由兩種 演算法（EZ-tracing 與tensor deflection）進 行神經纖維追蹤，並且比較兩種成像方式 所能夠追蹤出的神經纖維總體積。結果顯 示在FLAIR DTI 成像技術中，神經纖維追 蹤明顯較傳統DTI 為佳，特別是在接近腦 室與腦溝附近、富含腦脊髓液之處。在相 對不受腦脊髓液干擾的區域中，或許因為 FLAIR DTI 本身具有較低信雜比，而導致 小部份的追蹤錯誤，但並不影響主要白質 神經纖維束（例如胼肢體或冠狀輻射區） 的結果。扣除追蹤錯誤部份後，FLAIR DTI 平均偵測出比傳統DTI 多約17%體積的神 經纖維。因此，即使FLAIR DTI 具有較長 的掃瞄時間與略低的信雜比，該技術在神 經纖維追蹤方面仍有卓著的成效。The specific aim for the first fiscal year of this project is to test our hypothesis that the FLAIR technique helps to improve DTI white matter tractography by eliminating CSF partial volume effects. Seven healthy young adults aged 23-37 underwent both conventional and FLAIR DTI on a 1.5 Tesla system. Each subject was scanned five times. Tractography was performed with both sequences using two algorithms: One voxel-based method (EZ-tracing) with global seed points, and the other based on subvoxel tractography (tensor deflection) using manual encircling of local seed points. Total volume of the fibers tracked was compared for the two types of images. Fiber tracking was found to be substantially more successful in FLAIR DTI near the lateral ventricles and the sulci where CSF partial volume effects are likely to be present. Minor false tracts on FLAIR images possibly due to reduced SNR were found in regions relatively free from CSF contamination, but did not affect tracking of major peri-ventricular white matter bundles such as those related to the corpus callosum or the corona radiata. Excluding false tracts, the FLAIR technique detected an average of 17% more fibers in volume than with conventional DTI in the peri-ventricular regions (p < 0.0005). It is concluded that despite of reduced SNR and longer scan time, FLAIR is an effective means that helps to improve tractography.application/pdf138293 bytesapplication/pdfzh-TW國立臺灣大學電機工程學系暨研究所擴散張量影像白質神經纖維追 蹤部份體積效應流體抑制反轉回復腦脊髓液抑制Diffusion tensor imagingwhite matter tractographypartial volume effectsfluid-attenuated inversion recoveryCSF suppressionreporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/8064/1/932314B002143.pdf