Britz-Cunningham Scott H, Millstine John W, Gerbaudo Victor H
Division of Nuclear Medicine, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
Clin Nucl Med. 2008 Oct;33(10):681-7. doi: 10.1097/RLU.0b013e318184b435.
This study demonstrates a simple background correction method, which improves the discrimination of benign from malignant lesions on FDG PET-CT imaging, using activity ratios compared with brain, basal ganglia, or cerebellum.
Standardized uptake values (SUVs) and comparative activity ratios (CARs) were determined for FDG uptake in 92 lesions (39 benign and 53 malignant) in 49 patients. Reference tissues included cerebral cortex, basal ganglia, cerebellum, lung, liver, and aortic blood pool. Discriminant power for each CAR was evaluated as malignant-to-benign ratio of mean uptake and ratio of intermediate-likelihood lesions to total number of lesions.
Uncorrected SUV varied widely for malignant and benign lesions, with considerable overlap. Ratio of mean uptake for malignant lesions versus benign lesions was lowest for uncorrected SUVAVG and SUVAVG/liver (1.92), and highest for SUVMAX/cerebral cortex (3.52). Lesions could be separated into very high (> 90%), very low (< 10%), and intermediate (> or = 10% and < or = 90%) likelihood of malignancy. The ratio of intermediate-likelihood lesions to the total number of lesions was greatest for SUVAVG (0.42) and lowest for SUVMAX/basal ganglia (0.22).
Ability to discriminate malignant from benign lesions was enhanced by using CARs derived from cerebral cortex, basal ganglia, or cerebellum. Using a 3-tiered diagnostic schema, most lesions could be assigned to categories of very high or very low likelihood of malignancy, with a significant reduction in indeterminant lesions, compared with uncorrected SUV.
本研究展示了一种简单的背景校正方法，该方法通过与脑、基底神经节或小脑比较活性比值，提高了在FDG PET-CT成像上鉴别良性与恶性病变的能力。
测定了49例患者中92个病变（39个良性和53个恶性）的FDG摄取的标准化摄取值（SUV）和比较活性比值（CAR）。参考组织包括大脑皮质、基底神经节、小脑、肺、肝脏和主动脉血池。评估每个CAR的判别能力，以平均摄取的恶性与良性比值以及中等可能性病变与病变总数的比值来表示。
未校正的SUV在恶性和良性病变中差异很大，有相当程度的重叠。未校正的SUVAVG和SUVAVG/肝脏的恶性病变与良性病变的平均摄取比值最低（1.92），而SUVMAX/大脑皮质最高（3.52）。病变可分为恶性可能性非常高（>90%）、非常低（<10%）和中等（>或=10%且<或=90%）。中等可能性病变与病变总数的比值在SUVAVG时最大（0.42），在SUVMAX/基底神经节时最低（0.22）。
使用源自大脑皮质、基底神经节或小脑的CAR可增强鉴别恶性与良性病变的能力。采用三级诊断模式，与未校正的SUV相比，大多数病变可归为恶性可能性非常高或非常低的类别，不确定病变显著减少。
