MRI IDEAL測量脂肪量準確度之評估

Assessment of Accuracy of Fat Measurement By MRI IDEAL

郭宗濙(TSUNG-YING KUO)

指導教授 ： 楊素珍

中臺科技大學/健康科學院/醫學影像暨放射科學系暨研究所/碩士(2018年)

摘要

脂肪是人體組織中除了水以外最主要的成分。但脂肪量若是異常滯留或囤積於組織、器官時，將成為一種疾病的表現。本研究建立三種模擬體脂肪假體的模型，用以檢測磁振造影的IDEAL (iterative decomposition of water and fat using echo asymmetry and least-squares estimation)技術是否能精準作為各類脂肪疾病診斷的工具，以確認將IDEAL技術運用於臨床，提供給醫師針對肝臟脂肪量、肌肉脂肪量、體內外脂肪量等定量的鑑別工具。
本研究將豬油、豬肉、沙拉油三種不同種類的脂肪-水假體分別置入GE SIGNA HDx 1.5T MRI檢查儀中，使用2D FSE T1、T2與3D SPGR T1、T2* 的波序進行冠狀切面掃描，並分別測量脂肪-水影像中脂肪與水的體積，再針對沙拉油-水假體的脂肪影像，使用ROI (region of interest)測量不同脂肪比率的訊號強度，利用線性回歸分析檢定脂肪比率與訊號強度的相關性。
針對不同種類的脂肪-水假體，藉由IDAEL技術產生的脂肪影像測得脂肪訊號平均值，其準確度達95.38~99.68%。從沙拉油-水假體所取得的脂肪影像中，ROI測量得知脂肪含量比例與訊號強度間存在的線性相關R2值為0.9。
藉由脂肪-水假體所進行實驗，驗證IDEAL技術能在MRI中高準確度的分離脂肪，以確認IDEAL技術能成為臨床上定量診斷的有效工具。

關鍵字

磁振造影 ； IDEAL (iterative decomposition of water and fat using echo asymmetry and least-squares estimation) ； 脂肪假體 ； 定量

並列摘要

Most kinds of human tissues in addition to the ingredients other than water are fat. However, if the abnormal fat accumulation in the home stay or tissues or organs, it will be a disease of the performance. We will create three kinds of simulated body fat phantom. To check the IDEAL technique of MRI whether has the precise types of fat as a clinical tool for the detection disease. IDEAL techniques will be used to confirm the clinical, available to clinicians as a tool for the amount of liver fat, muscle fat mass, fat mass in vivo detection.
The lard, pork, salad oil of three different types of fat-water phantom were placed in GE SIGNA HDx 1.5T MRI examination instrument. It is using the 2D FSE T1、T2 and 3D SPGR T1、T2* sequence for coronal wave scan. We measured the fat and water images in the volume of fat and water subjects, and then for the salad oil-water phantom fat images. We want to measurement the signal strength of different fat percentage by ROI. The fat percentage got from liner regression analysis correlation and signal strength.
For different types of fat - water phantom. The value of the image signal converted by IDAEL average measurements the accuracy of 95.38%~ 99.68%. From the salad oil - water phantom images obtained by the fat. The ROI measurement of fat content that exists between the ratio and the signal strength of the linear relations of the R2 value is 0.9.
IDEAL technique of MRI has been able to accurately separate the fat from the body tissue. Fat - water phantom of the experiment can also confirm the IDEAL technique in can be a useful tool for clinical quantitative diagnosis.

並列關鍵字

MRI ； IDEAL ； Fat phantom ； Quantitative

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