Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA.
Clinical Translational Neuroscience Branch at the National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
Pediatr Radiol. 2019 May;49(6):784-790. doi: 10.1007/s00247-019-04355-y. Epub 2019 Mar 12.
Peritoneal free fluid can indicate an underlying disease process; however detection of minimal peritoneal free fluid in healthy children is not uncommon.
To assess the significance of incidental peritoneal free fluid within healthy children by MRI and its relation to physiological changes during puberty.
This prospective study was performed on 32 healthy volunteers (20 boys) between the ages of 8 years and 13 years, with consecutive follow-ups every 8-10 months for an average of 3 years. Body mass index (BMI) z-score, pubertal status, C-reactive protein and sex hormone concentrations were assessed prior to MRI studies. We reviewed a total of 120 pelvic MRI studies (61 boys) and measured the quantity of peritoneal free fluid. For statistical analysis we used linear mixed-model accounting for within-patient correlations.
The mean ± standard deviation volume of peritoneal free fluid was 4.7±5.7 mL in girls and 1.9±3.1 mL in boys, with a maximum volume of 25 mL and 17 mL, respectively. The prevalence of peritoneal free fluid was significantly higher in girls (91%) compared to boys (67%; P=0.0035). In 15% of the girls and 3% of the boys the fluid was greater than 10 mL. The mean volume of peritoneal free fluid in the fourth stage of puberty was higher and significantly different from the mean volume in the first stage of puberty (P=0.01).
Among healthy pubescent children, the prevalence of peritoneal free fluid is significantly higher in girls. The volume of peritoneal free fluid can reach volumes greater than 10 mL during normal puberty, especially in the fourth stage, and can be assumed normal in the absence of active disease.
腹膜游离液可提示潜在疾病过程；然而，在健康儿童中检测到少量腹膜游离液并不罕见。
通过 MRI 评估健康儿童腹膜游离液的偶然存在及其与青春期生理变化的关系。
本前瞻性研究纳入了 32 名 8-13 岁的健康志愿者（20 名男孩），连续随访 8-10 个月，平均随访 3 年。在 MRI 研究之前评估了体重指数（BMI）z 评分、青春期状态、C 反应蛋白和性激素浓度。我们共回顾了 120 例盆腔 MRI 研究（61 例男孩）并测量了腹膜游离液的量。统计分析采用线性混合模型，考虑了个体内相关性。
女孩腹膜游离液的平均体积±标准差为 4.7±5.7 mL，男孩为 1.9±3.1 mL，最大体积分别为 25 mL 和 17 mL。腹膜游离液的发生率在女孩（91%）明显高于男孩（67%；P=0.0035）。在 15%的女孩和 3%的男孩中，液体量大于 10 mL。第四阶段青春期腹膜游离液的平均体积更高，与第一阶段青春期的平均体积有显著差异（P=0.01）。
在健康青春期儿童中，女孩腹膜游离液的发生率明显更高。腹膜游离液的体积在正常青春期期间可以达到 10 mL 以上，尤其是在第四阶段，在没有活动性疾病的情况下可以认为是正常的。
