衰减校正在18F-FDG符合显像中对肺癌纵隔淋巴结转移的诊断价值

目的:评价137Cs穿透衰减校正(AC)在氟?眼18F?演-2-脱氧葡萄糖(18F-FDG)符合显像中对肺癌纵隔淋巴结转移的诊断价值。方法:对54例肺癌纵隔淋巴结转移患者行18F-FDG符合显像,衰减校正采用137Cs点源,分别重建有衰减校正和无衰减校正(NAC)图像。统计肺部及纵隔淋巴结转移病灶的数目,并对两组图像进行比较分析。结果:54例患者AC图像共检出肺部病灶55个,纵隔病灶154个。NAC图像共检出肺部病灶55个,纵隔病灶127个。所有病例中AC与NAC病灶数目相同者31例(57%),AC病灶数目多于NAC者21例(39%),AC病灶数目少于NAC者2例(4%)。AC检出纵隔淋巴结转移病灶而NAC未检出者4例(7%)。结论:AC图像质量明显优于NAC图像,AC对肺部病灶的检出率无明显改善,但对纵隔淋巴结转移病灶的检出率有较大提高。

The value of the attenuation correction in diagnosis of patients with lung cancer and mediastinal nodal metastases using 18F-FDG coincidence imaging

Objective: To evaluate the value of the 137Cs attenuation correction(AC) in diagnosis of patients with lung cancer and mediastinal nodal metastases(MNM) using 18F-FDG coincidence imaging. Method: Fifty-four patients were studied with 18F-FDG imaging and the attenuation correction map were acquired with 137Cs point sources. The raw data were reconstructed with AC and no AC(NAC) respectively, then the total number of lesions in lungs were added up with the number of MNM. Finally, the images with AC and those with NAC were compared. Results: For all 54 patients, 55 lesions in lungs and 154 MNM were detected with AC, and lesions detected with NAC were 55 and 127 respectively. The total number of lesions with AC or NAC were the same in 31(57%) patients, while more lesions with AC were detected than that with NAC in 21(39%) patients, and the less lesion detected with AC than that with NAC in 2 (4%) patients. As to the MNM, 4(7%) patients with AC had the positive results, but none with NAC for the same patients. Conclusion: The image quality with AC was better than that with NAC. The AC method could obviously enhance the MNM detection rate, even the detection ability in lungs with AC was the same as that with NAC.