Division of Nuclear Medicine, Department of Medical Radiology, University Hospital of Zurich, Ramistr. 100, 8091, Zurich, Switzerland.
Eur J Nucl Med Mol Imaging. 2011 Jan;38(1):90-6. doi: 10.1007/s00259-010-1618-7. Epub 2010 Sep 21.
The aim of the study was to determine the aetiology of FDG uptake in vaginal tampons (VT), a known artefact in premenopausal women evaluated by PET/CT.
This Institutional Review Board approved study consisted of retrospective and prospective parts. The retrospective analysis included 685 women examined between January 2008 and December 2009 regarding VT presence. PET/CT images were analysed to determine the localization and the standardized uptake value (SUV) of VTs. We prospectively recruited 24 women (20-48 years old) referred for staging or follow-up in an oncology setting between February and April 2010, who were provided a commercial VT to be used during the entire examination after obtaining written informed consent. After image acquisition, VTs were individually analysed for creatinine concentration and blood traces. Statistical significance was tested with the Mann-Whitney U test.
In the retrospective part, 38 of 685 women were found to have a VT of which 17 (45%) were FDG positive. A statistically significant correlation was found between FDG activity and VT position below the pubococcygeal line (PCL) (13 ± 11.2 mm). In the prospective study, 7 of 24 (29%) women had increased FDG activity in their VTs (SUV 18.8 ± 11 g/ml) but were not menstruating. FDG-positive VTs were significantly lower in position (14.6 ± 11.4 mm,below the PCL) than FDG-negative VTs (p = 0.039). The creatinine concentration was significantly increased in all seven positive VTs (931 ± 615 μmol/l).
FDG uptake in VTs is caused by urine contamination, which is likely related to localization below the PCL resulting in contact with urine during voiding.
本研究旨在确定阴道填塞物（VT）摄取 FDG 的病因，这是 PET/CT 评估绝经前女性时已知的一种伪影。
这项经机构审查委员会批准的研究包括回顾性和前瞻性两部分。回顾性分析纳入了 2008 年 1 月至 2009 年 12 月期间因 VT 存在而接受检查的 685 名女性。分析 PET/CT 图像以确定 VT 的定位和标准化摄取值（SUV）。我们前瞻性招募了 24 名女性（20-48 岁），她们在 2010 年 2 月至 4 月期间因肿瘤分期或随访而被安排在肿瘤学环境中，在获得书面知情同意后，每位女性都使用了商业 VT 进行整个检查。图像采集后，单独分析 VT 的肌酐浓度和血液痕迹。采用 Mann-Whitney U 检验进行统计学意义测试。
在回顾性部分，685 名女性中有 38 名发现 VT，其中 17 名（45%）FDG 阳性。FDG 活性与 VT 位于耻骨尾骨线（PCL）以下的位置（13 ± 11.2mm）之间存在统计学显著相关性。在前瞻性研究中，24 名女性中有 7 名（29%）的 VT 中 FDG 活性增加（SUV 18.8 ± 11g/ml），但未处于月经期。与 FDG 阴性 VT 相比，FDG 阳性 VT 的位置（14.6 ± 11.4mm，低于 PCL）明显更低（p=0.039）。所有 7 个阳性 VT 的肌酐浓度均显著升高（931 ± 615μmol/l）。
VT 摄取 FDG 是由尿液污染引起的，这可能与位于 PCL 以下导致排尿时与尿液接触有关。
