探討MAMMI PET對小動物造影之可行性研究

Investigating the feasibility study of MAMMI PET for small animal imaging

彭毓婷(Yu-Ting Peng)

指導教授 ： 陳泰賓

義守大學/智慧科技學院/資訊工程學系/碩士(2022年)

摘要

正子放射電腦斷層掃描是一種非侵入性、可提供功能影像的診斷工具，臨床上主要利用大型醫用正子電腦斷層掃描儀( positron emission tomography, PET)及單光子斷層掃描儀(single-photon emission computed tomography, SPECT)來取得功能性影像；而針對小動物造影，則有小型具高解析度的動物用PET，因具有可提供動物體內生物分布資訊及可重複實驗的特性，在藥物開發及諸多研究上，是臨床前動物實驗所必須，也是最有效的工具。
本研究採用假體實驗與動物實驗設計，假體實驗依其FDG劑量、造影時間、造影參數、重建方法的不同來分析其影像之空間解析度、均勻度、靈敏度；動物實驗則為正常小白鼠的正子斷層掃描，對比小白鼠進食前後的影像差異來驗證此系統對小動物造影研究是否能提供功能影像。設計驗證影像品質方法：使用MAMMI Breast PET進行小動物造影之特性評估，包括空間解析度(spatial resolution)、均勻度(uniformity)及靈敏度(sensitivity)，掃描模式使用single mode，並分別提供Standardization、Isotope fall-off、Scatter events、Attenuation by segmentation、Random events五種修正，使用3D-MLEM影像重建法，來評估及量化其影像品質。
本研究已完成MAMMI Breast PET對小動物造影研究之可行性，並提供一個小動物實驗研究所需之造影程序及參數之參考資訊。本研究動物實驗使用造影模式及參數為: (1)靜態攝影、(2)取樣時間: 5分鐘、(3)注射劑量為0.1 mCi/0.1 ml、(4)衰減修正採用Standardization方法。透過假體實驗可得MAMMI Breast PET之空間解析度，軸向平均1.946 mm、徑向1.824 mm、影像均勻度最高96%、靈敏度平均為1.087%，實驗結果顯示利用MAMMI PET對小動物造影具有可行性。

關鍵字

正子斷層掃描 ； 小動物造影

並列摘要

Positron emission computed tomography is a non-invasive diagnostic tool that can provide functional images. Clinically, large-scale medical Positron Emission Tomography (PET) and Single-Photon Emission Computed Tomography (SPECT) are mainly used. For small animal imaging, there is small and high-resolution PET for animals. Because of its characteristics of providing biological distribution information in animals and reproducibility, it is used in drug development and many types of research. PET is a necessary and most effective tool for pre-clinical animal experiments.
This study adopts the design of phantom and animal experiments. A phantom study evaluated the dose, contrast time, contrast parameters, and reconstructed methods. The functional imaging for a small animal was imaging by MAMMI PET with compared differences of activity between fasting and eating conditions. Meanwhile, the imaging protocols included injection dose, scanning time, a schema of correction, and reconstructed methods in this study. By the way, the spatial resolution and uniformity of the reconstructed image and the sensitivity of detected gamma rays were used to evaluate the PET scanner's performance and image quality.
This study evaluated the feasibility of imaging small animals by MAMMI Breast PET. The scanner could provide imaging procedures and parameters required for experimental studies in small animals. The imaging protocols and parameters used in animal experiments could be set as single mode, scanning time 5 minutes, injected dose 0.1 mCi/0.1 ml, and attenuation correction by standardization. The average horizontal and vertical axial resolutions are 1.946 and 1.824 mm. The uniformity of the reconstructed image is 96%. The average sensitivity of detected gamma rays is 1.087%. Hence, it is useful and feasible to study small animal imaging using MAMMI PET.

並列關鍵字

Positron Emission Tomography ； Small Animal Imaging ； FDG

參考文獻

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