FDG PET and dual-head gamma camera positron coincidence detection imaging of suspected malignancies and brain disorders.
نویسندگان
چکیده
UNLABELLED The purpose of the study was to compare the diagnostic accuracy of fluorodeoxyglucose (FDG) images obtained with a dual-head coincidence gamma camera (DHC) with those obtained with a dedicated PET in a series of 26 patients. METHODS Nineteen patients with known or suspected malignancies and 7 patients with neurological disorders underwent PET imaging after injection of approximately 10 mCi of FDG. Whole-body imaging was performed on 19 patients and brain imaging on 7 patients. DHC images were then acquired for 30 min over the region of interest using a dual-head gamma camera equipped with 3/8-in.-thick NaI(TI) crystals and parallel slit-hole collimators. The images were reconstructed in the normal mode, using photopeak/photopeak, photopeak/Compton and Compton/photopeak coincidence events. RESULTS Although the spatial resolutions of PET with a dedicated PET scanner and of DHC are in the same range, the lesion detectability remains superior with PET (4 mm for PET versus 13.5 mm for DHC in phantom experiments) with a contrast ratio of 5:1. This is most probably attributable to the higher sensitivity of PET (2238 coincidences/min/microCi for PET versus 89 coincidences/min/microCi for DHC). The pattern of uptake and interpretation for brain imaging was similar on both PET and DHC images in all patients. In the 19 oncology patients, 38 lesions ranging from 0.7 to 5 cm were detected by PET. DHC imaging detected 28 (73%) of these lesions. Among the 10 lesions not seen with DHC, 5 were less than 1.2 cm, 2 were located centrally within the liver and suffered from marked attenuation effects and 3 were adjacent to regions with high physiological activity. The nondetectability of some lesions with DHC compared with PET can be explained by several factors: (a) start of imaging time (mean+/-SD: 73+/-16 min for PET versus 115+/-68 min for DHC, leading to FDG decay to 6.75 mCi for PET and 5.2 mCi for DHC); (b) limited efficiency of a 3/8-inch-thick Nal(TI) crystal to detect 18F photons; (c) suboptimal two-dimensional reconstruction algorithm; and (d) absence of soft-tissue attenuation correction for centrally located lesions. CONCLUSION FDG DHC imaging is a promising technique for oncological and brain imaging.
منابع مشابه
Brain fluorine-18 fluorodeoxyglucose imaging with dual-head coincidence gamma camera: comparison with dedicated ring-detector positron emission tomography.
BACKGROUND AND PURPOSE Dual-head coincidence gamma camera (DHC) imaging has been proposed as an alternative to dedicated ring-detector positron emission tomography (dr-PET) for clinical fluorodeoxyglucose (FDG) studies. The purpose of this investigation was to assess the quality of DHC images in FDG studies of the human brain. METHODS Seven healthy volunteers and 12 patients with various cere...
متن کاملUsefulness of dual-head coincidence gamma camera with thick NaI crystals for nuclear oncology: comparison with dedicated PET camera and conventional gamma camera with thin NaI crystals.
AIM A comparative study of the images obtained with a dual-head coincidence gamma camera with thick NaI crystals (19 mm), a dedicated PET camera with BGO crystals and a conventional gamma camera with thin NaI crystals (9.5 mm) was conducted to clarify the clinical feasibility of a dual-head coincidence gamma camera with thick NaI crystals. METHODS FDG images of 27 patients with malignant tumo...
متن کاملPET Radiopharmaceuticals
PET (positron emission tomography) is a powerful imaging technique that can provide quantitative information on the distribution of positron emitter labeled radiopharmaceuticals (PET radiopharmaceuticals) in the body. Positrons (ß+) are positively charged beta particles. They are emitted when the atom is proton rich. A positron has only a transient existence. After losing all of its kinetic ene...
متن کاملPET Radiopharmaceuticals
PET (positron emission tomography) is a powerful imaging technique that can provide quantitative information on the distribution of positron emitter labeled radiopharmaceuticals (PET radiopharmaceuticals) in the body. Positrons (ß+) are positively charged beta particles. They are emitted when the atom is proton rich. A positron has only a transient existence. After losing all of its kinetic ene...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of nuclear medicine : official publication, Society of Nuclear Medicine
دوره 40 1 شماره
صفحات -
تاریخ انتشار 1999