Département de radio-oncologie et Centre de recherche en cancérologie de l'Université Laval, Hôtel-Dieu de Québec, Québec, Canada.
Int J Radiat Oncol Biol Phys. 2010 Nov 15;78(4):1052-6. doi: 10.1016/j.ijrobp.2009.09.012. Epub 2010 Mar 6.
To evaluate the efficacy of a seed-migration detector and to compare its performance to fluoroscopy and postoperative chest radiographs.
A gamma scintillation survey meter was converted to a seed-migration detector by adding a shield on the probe detection window. The detector response to three (125)I seed activities was characterized for different source-to-detector distances in water. The detector was used to perform a chest evaluation on 737 patients at their first postoperative visit. When the detector showed positive activity, seed migration was confirmed by taking a chest radiograph and by looking at the region with fluoroscopy.
One hundred and three patients (14.0%) presented at least one embolized seed. This accounts for 123 of the 39,887 seeds. Eighty-seven, 12, and 4 patients had respectively one, two, and three seed embolization. Compared with the seed-migration detector, detection based on fluoroscopy would have led to 13 false-negative detections (of 103, or 12.6%), and the radiograph would have resulted in 31 or 30.1%. More important, standard chest X-ray would have required a survey and extra radiation dose to lung to 100% of the patients, rather than the 14% who required it.
The usual recommendation to perform chest radiographs at the first follow-up visit to scan lungs for embolized seeds should be revised because of the high false-negative rate. Scintillator-based gamma counter detector provides superior detection sensitivity and should be adopted as a standard of practice. Chest X-ray could be limited to documenting cases of positive migration.
评估一种种子迁移探测器的功效，并将其性能与透视和术后胸部 X 光片进行比较。
通过在探头检测窗口上添加屏蔽，将伽马闪烁计数器转换为种子迁移探测器。探测器对水中共三个（125）I 种子活动的响应在不同的源-探测器距离下进行了表征。该探测器用于在 737 名患者首次术后就诊时进行胸部评估。当探测器显示阳性活动时，通过拍摄胸部 X 光片和透视检查来确认种子迁移。
103 名患者（14.0%）至少出现了一个栓塞的种子。这占 39887 个种子中的 123 个。分别有 87、12 和 4 名患者发生了一个、两个和三个种子栓塞。与种子迁移探测器相比，透视检测将导致 13 次假阴性检测（103 次中的 12.6%），而 X 光片将导致 31 次或 30.1%。更重要的是，标准的胸部 X 光片需要对 100%的患者进行调查和额外的肺部辐射剂量，而不是需要的 14%。
由于假阴性率高，通常建议在首次随访时进行胸部 X 光片检查以扫描肺部的栓塞种子，这一建议应进行修订。基于闪烁体的伽马计数器探测器提供了更高的检测灵敏度，应被采纳为标准的实践。胸部 X 光片可以仅限于记录阳性迁移的病例。
