Characterization of hilar lymph node by 18F-fluoro-2-deoxyglucose positronemission tomography in healthy subjects

One hundred and seventy-nine images were collected from healthy subjects wh o underwent whole-body 18F-fluoro-2-d-deosyglucose positron emission tomogr aphy (FDG-PET) for health examination. Images showing visually increased FD G uptake based on a five-pont visual scale in the hilar regions were includ ed for analyses. We evaluated the sizes, standard uptake values (SUV), and lesion-to-background (L/B) ratios of the hilar lymph nodes (HLN). Fifty of 179 (28%) subjects had visually increased FDG uptake in the hilar regions w ith a total of 84 HLN. By a five-pont visual scale, 67 out of 84 (7.8%) HLN were grade 2, 16 out of 87 (19%) were grade 3, and 1 out of 84 (1.2%) was grade 4. The average size of th HLN was 1.55x1.46 cm. SUV of the HLN ranged from 1.132-2.975 with an average of 1.8+/-0.44. L/B ratio of the HLN range d from 1.05-2.63 with an average of 1.52+/-0.39. Twenty-eight % of healthy subjects who underwent whole-body FDG-PET demonstrated visually increased F DG uptake in the HLN. However, alla of the 84 HLN had a size <2x2 cm, SUV < 3.0 and L/B ratios <3.