利用功能性影像及早偵測出異常的生理變化，使病人可以在癌症的早期獲得適當的治療，是值得發展的技術。在本論文中利用核研所物理組自製的旋轉式正子造影系統作為實驗平台來進行一系列假體實驗，希望藉此探討利用正子乳房造影來偵測乳癌的可行性。系統是使用一對相對1800且距離220mm的BGO偵檢器在不旋轉的情況下來擷取數據，並利用MLEM演算法處理三維數據完成影像重建的工作。從重建影像上可以分辨腫瘤假體的大小以及其在乳房假體中的位置，在腫瘤假體尺寸達2mm直徑的大小仍可清楚分辨。即使在腫瘤假體與背景單位體積活度比(tumor-to-background concentration ratio)為5：1時仍然可以顯現尺寸為10mm直徑的腫瘤假體。至於視野外射源(如：心臟)的干擾亦不會影響對於腫瘤假體大小及位置的判斷。乳癌偵測的目的，是正確的顯示有無腫瘤，以及腫瘤大小與位置，並且在可以接受的檢測時間和所接受的輻射劑量下達成。在本研究中估計可以在600秒下偵測尺寸2mm活度為22.2kBq(0.6 Ci)的腫瘤假體，並且僅花12秒的影像重建時間(疊代次數選為十)。

It is a considerable issue that how to use the functional images for early detecting breast cancer. In this thesis, the feasibility of positron emission mammography (PEM) in detecting breast tumors were investigated with a series of phantom experiments using rotational PET imager developed by Institute of Nuclear Energy Research. The PEM system understudy only uses two opposite BGO detectors, which separated by 220mm. And we employed MLEM algorithm to reconstruct the three-dimensional images. The locations and sizes of the hot spots in breast phantom can be determined from the reconstructed images. The minimum detectable sphere diameter is 2mm. At the target-to-background concentration ratio 5:1, the 10mm size sphere can be visible. And the source out of FOV dose not influence the capability of determining the locations and sizes. In our research, calculation shows that it is possible detecting 2mm size sphere with 22.2kBq in 600 seconds and spending 12 seconds to reconstruction (10 iterations).

參考文獻

Ciatto S, Rosselli del Turco M, Catariz S, Morrone D 1994 The contribution of ultrasonography to the differential diagnosis of breast cancer Neoplasma 41 341-5
Cronin B, Marsden P K and O’Doherty M J 1999 Are restrictions to behavior of patients required following fluorine-18 fluorodeoxyglucose positron emission tomographic studies? Eur. J. Nucl. Med. 26 121-8
Gruber G J, Moses W W and Derenzo S E 1999 Monte Carlo Simulation of Breast Tumor Imaging Properties with Compact, Discrete Gamma Cameras IEEE Trans. Nucl. Sci. 46 2119-23
Huesman R H, Klein G J, Moses W W, Qi J, Reutter B W and Virador P R G 2000 List-Mode Maximum-Likelihood Reconstruction Applied to Positron Emission Mammography (PEM) with Irregular Sampling IEEE Trans. Nucl. Sci. 19 532-7
International Commission on Radiological Protection 1990 Recommendation of the International Commission on Radiological Protection Publication 60 Oxford, U.K.:Pergamon Press 4-11
Jan M L, Liang H C, Huang S W, Tang J S, Pei C C and Yeh C K 2001 Preliminary results from the AROPET IEEE Nucl. Sci. Symposium and Image conference November 4-10
Levin C S 2003 Detector design issues for compact nuclear emission cameras dedicated to breast imaging Nucl. Instr. and Meth. A 497 60-74
Love S M and Lindsay K 2002 Dr. Susan Love’s Breast Book
Moore S K 2001 Better breast cancer detection IEEE Spectrum 38 50-4
Moses W W and Oi J 2003 Fundamental limits of positron emission mammography Nucl. Instr. And Meth A 497 82-9
Murthy K, Aznar M, Thompson C J, Loutfi A, Lisbona R and Gagnon J H 2000 Results of Preliminary Clinical Trials of the Positron Emission Mammography System PEM-I: A Dedicated Breast Imaging System Producing Glucose Metabolic Images Using FDG J. Nucl. Med. 41 1851-8
Qi J, Klein G J and Huesman R H 2001 Image Properties of List-mode Likelihood Reconstruction for a Rectangular Positron Emission Mammography with DOI Measurement IEEE Trans. Nucl. Sci. 48 1343-9
Qi J and Huesman R H 2002 Scatter Correction for positron emission mammography Phys. Med. Biol. 47 2759-71
Raylman R R, Majewski S, Wojcik R, Weisenberger A G, Kross B and Bishop H A 2000 The potential role of positron emission mammography for detection of breast cancer. A phantom study Med. Phys.27 1943-54
Raylman R R, Majewski S, Wojcik R, Weisenberger A G, Kross B and Popov V 2001 Corrections for the effects of Accidental Coincidences, Compton Scatter, and Object Size in Positron Emission Mammography (PEM) Imaging IEEE Trans. Nucl. Sci. 48 913-23
Raylman R R, Majewski S, Smith M F, Wojcik R, Weisenberger A G, Kross B, Popov V and Derakhshan J J 2003 Comparison of Scintillators for Positron Emission Mammography (PEM) System IEEE Trans. Nucl. Sci. 50 42-9
Schirrmeister H, Kuhn T, Guhlmann A, et al 2001 Fluorine-18 2-deoxy-2-fluoro-D-glucose PET in the preoperative staging of breast cancer: comparison with the standard imaging procedures Eur. J. Nucl. Med. 28 351-8
Scopinaro F, Schillaci O, Ussof W, Nordling K, Capoferro R, De Vincentis G, Danieli R, Ierardi M, Picardi V, Tavolaro R and Colella A C 1997 A three center study on the diagnostic accuracy of 99mTc-MIBI scintimammography Anticancer Research 17 1631-4
Scopinaro F, Mezi S, Ierardi M, De Vincentis G, Tiberio N S, David V, Maggi S, Sallusti E and Modesti M 1998 99mTc MIBI prone scintimammography in patients with suspicious breast cancer: Relationship with mammography and tumor size Int. J. Oncol. 12 661-4
Smith M F, Majewski S and Raylman R R 2002 Positron Emission Mammography with Multiple Angle Acquisition IEEE Nucl. Sci. Symposium conference 3 1892-6
Smith M F, Majewski S, Weisenberger A G, Kieper D A, Raylman R R and Turkington T G 2003 Analysis of Factors Affecting Positron Emission Mammography (PEM) Image Formation IEEE Trans. Nucl. Sci. 50 53-9
Thompson C J, Murthy K, Picard Y, Weinberg I N and Mako R 1995 Positron Emission Mammography (PEM): A Promising Technique for Detecting Breast Cancer IEEE Trans. Nucl. Sci. 42 1012-17
Zhang N, Thompson C J, Cayouette F, Jolly D and Kecani S 2003 A Prototype Modular Detector Design for High Resolution Positron Emission Mammography Imaging IEEE Trans. Nucl. Sci. 50 1624-9