- 學位論文
超順磁性氧化鐵造影劑於肝臟擴散加權影像的應用
The application of SPIO-contrast agent used for liver MR diffusion weighted imaging
摘要
肝臟腫瘤分列為男性第一位及女性第二位的高致死率。傳統上使用理學檢查、實驗室血液生化檢查以及影像學方面包括電腦斷層、超音波、磁振造影等方式的檢查做為診斷的依據。本研究藉由擴散加權影像造影(diffusion weighted imaging; DWI)在超順性氧化鐵離子造影劑(super paramagnetic iron oxide; SPIO)注射後，並在有適當的影像後處理程序下，提高評估肝臟腫瘤上的正確性。 本研究篩選疑似肝臟腫瘤病患10人做為本研究取樣的對象，實施傳統肝臟磁振造影，以及SPIO注射前所實施的DWI肝臟磁振造影，之後實施一組與DWI波序在幾何條件上完全相符的T1W影像，以提供解剖資訊上影像融合的基礎，並在SPIO注射後10分鐘、20分鐘及30分鐘後實施DWI肝臟磁振造影。為評估DWI肝臟磁振造影的特異性(specificity) ，我們亦選取五名無肝膽系統疾病之健康志願者，實施傳統肝臟磁振攝影及SPIO注射前的DWI肝臟磁振造影，做為實驗的對照組。再以mathlab影像處理程式，運用影像分析的方式，將所獲得的肝臟擴散加權影像，分割(segmentation)並以適當的數位濾波(digital filter)強化影像的邊緣（edge enhancement），以繪製出病灶的範圍，並T1加權影像Fusion 在一起，藉此同時獲得功能性與解剖學上的資訊。此外，兩名具專科醫師資格的放射線診斷醫師個別獨立的對這些傳統磁振攝影影像進行判讀。 初步結果顯示，本研究所採取的技術，在所有符合評估標準的八名受測病患中皆能準確的偵測出病灶的位置，其敏感度(sensitivity)為1；同時在五名正常志願者的測試中，DWI肝臟磁振造影亦無偵測出假陽性病灶，其特異性(specificity)為1。此外，各判讀醫師對此技術的滿意度亦高達93.75%。 我們預期此一結合SPIO-enhanced MR imaging與DWI的技術，作為一種輔助性的工具，應可普遍應用在臨床MRI造影上。配合傳統肝臟磁振造影及SPIO-enhanced MR imaging的實施相信對臨床上肝臟病灶的偵測上應有絕對的幫助，同時亦可大幅提高臨床上肝臟病灶的偵測率。
並列摘要
Hepatic tumor was the top of deadly diseases for male and the second deadly diseases for female in Taiwan. Traditional, physical examination, laboratory blood test and medical imaging including computer tomography (CT), ultrasound and magnetic resonance imaging (MRI) were used for hepatic lesions diagnosis. The purpose of this study is to evaluate the accuracy of hepatic lesion detection after Super paramagnetic iron oxide (SPIO) injection followed by diffusion weighted imaging (DWI). Ten patients with suspected hepatic tumors were recruited for this study. For each patient, conventional MR liver scanning and pre-SPIO diffusion weighted imaging (DWI) were performed before contrast agent administration. Additional, a T1 weight (T1W) imaging series with the same geometric characterizes was performed for images fusion. Then 10min, 20min, 30min after SPIO administration DWI were performed. Five volunteers without any biliary system diseases were chosen to perform conventional MR liver scanning and pre-SPIO diffusion weighted imaging (DWI) to evaluate the specificity in this study. Moreover, an image processing program was used to segmentation and enhances the edge of hepatic tumor; T1W images were fused with these post-processed DWI to archive both anatomic and functional information. Then, these images were elevated independently by two radiologists with blind patient’s clinical information The primary result shows that all the present lesions of the eight patients could be detected, i.e. the sensitivity is 1; and during the volunteer group test, no any false positive lesion has been detected, therefore the specificity is 1. This technique also has been reviewed by radiologists and the satisfaction level is up to 93.75%. Therefore, to be an assisted tool, we expect that by combining this technique with SPIO-enhanced MR imaging and DWI, can become a popular method for hepatic lesions detection in MR scanning. Coordinated with SPIO-enhanced MR imaging and DWI, SPIO-enhanced MR imaging, we believe this technique is useful and can increase the ability of lesion detection ratio significantly.