PURPOSE To determine the clinically acceptable level of reduction in the injected fluorine-18 (18F)-labeled fluorodeoxyglucose (18F-FDG) dose in dedicated breast positron emission tomography (dbPET). METHODS A breast phantom with four spheres exhibiting various diameters (5, 7.5, 10, and 16 mm), a background 18F-FDG radioactivity of 2.28 kBq/mL, and a sphere-to-background radioactivity ratio of 8:1 was used. True dose-reduced dbPET images were obtained by data acquisition for 20 min in list mode at multiple time points over 7 h of radioactive decay. Simulated dose-reduced images were generated by reconstruction with a portion of the list mode acquisition data. True and simulated dose-reduced images were visually and quantitatively compared. On the basis of the phantom study, dbPET images for 32 breasts of 28 women with abnormal uptake were generated after simulated reduction of the injected 18F-FDG doses; these images were compared with those acquired using current clinical doses. RESULTS There were no qualitative differences between true and simulated dose-reduced phantom images. The phantom study revealed that the minimal required dose was 12.5% for the detection of 5-mm spheres and 25% for precise semi-quantification of FDG in the spheres. The 7-min reconstruction with a 100% dose was defined as the reference for the clinical study. The image quality and lesion conspicuity were clinically acceptable for the 25% dose images. Lesion detectability on the 12.5% dose images was maintained despite image quality degradation. CONCLUSIONS In summary, 25% of the standard 18F-FDG dose for dbPET can provide a clinically acceptable image quality, while 12.5% of the standard dose results in acceptable quality in terms of lesion detection when lesions are located at a sufficient distance from the edge of the dbPET detector.

中文翻译：

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减少氟18标记的氟脱氧葡萄糖的剂量，用于临床专用的乳房正电子发射断层扫描。

目的确定在专用的乳房正电子发射断层扫描（dbPET）中注射的氟18（18F）标记的氟脱氧葡萄糖（18F-FDG）剂量的减少量的临床可接受水平。方法使用具有四个直径（5、7.5、10和16 mm）的球形的乳房体模，背景18F-FDG放射性为2.28 kBq / mL，球与背景的放射性比为8：1。在7小时的放射性衰变中的多个时间点，通过列表模式下20分钟的数据采集获得了真实剂量降低的dbPET图像。通过使用一部分列表模式采集数据进行重建，生成了模拟的剂量减少图像。对真实和模拟的减量图像进行视觉和定量比较。根据幻像研究，模拟降低注射的18F-FDG剂量后，生成了28例摄取异常的女性的32个乳房的dbPET图像；将这些图像与使用当前临床剂量获得的图像进行比较。结果真实和模拟剂量减少的幻影图像之间没有质的差异。幻像研究表明，检测5毫米球体所需的最低剂量为12.5％，而对球体中的FDG进行精确的半定量则为25％。以100％剂量进行的7分钟重建被定义为临床研究的参考。对于25％剂量的图像，图像质量和病变明显程度在临床上是可以接受的。尽管图像质量下降，但在12.5％剂量图像上仍保持病变可检测性。结论总而言之，