Division of Pediatric Urology and Department of Medical Imaging, Lurie Children's Hospital, Chicago and Department of Urology, Loyola University Stritch School of Medicine, Maywood, Illinois, USA.
J Urol. 2013 Apr;189(4):1519-23. doi: 10.1016/j.juro.2012.10.019. Epub 2012 Oct 16.
Treating constipation in children with voiding dysfunction may improve or resolve urinary symptoms. A clinical diagnosis of constipation may not identify all patients. Abdominal radiographs (plain x-ray of the kidneys, ureters and bladder) are often used to assess constipation but no objective definition of constipation based on abdominal radiographs exists. Most abdominal radiograph rating scales use subjective criteria and our previous series showed that these scales have poor reliability. We identified reliable, objective parameters on abdominal radiograph to predict constipation.
The abdominal radiographs of 80 children 4 to 12 years old, including 40 with constipation and 40 successfully treated for constipation, were assessed for several measurable parameters. Logistic regression was used to construct a model to predict constipation status based on these abdominal radiograph parameters. Model accuracy was assessed using AUC analysis of ROC curves.
The most predictive model included cecal diameter, total length of stool measured, stool length in the rectum, and patient age and gender. As measured by the area under the ROC curve, accuracy was excellent at 0.87. We calculated cutoffs for individual parameters on abdominal radiograph, including total stool length greater than 33.4 cm, cecal diameter greater than 3.7 cm and stool length in the rectum greater than 5.9 cm.
We identified accurate, reliable criteria based on objective measurements on abdominal radiograph to differentiate patients with and without constipation. These criteria may be applied to objectively assess constipation status in children with urinary symptoms without a history of constipation. Further study will determine whether these criteria predict the response to treatment.
治疗排尿功能障碍儿童的便秘可能会改善或解决排尿症状。临床诊断的便秘可能无法识别所有患者。腹部 X 线（肾脏、输尿管和膀胱的平片）常用于评估便秘，但基于腹部 X 线的便秘没有客观定义。大多数腹部 X 射线评分量表使用主观标准，我们之前的系列研究表明这些量表的可靠性较差。我们确定了腹部 X 射线的可靠、客观参数来预测便秘。
评估了 80 名 4 至 12 岁儿童的腹部 X 射线，其中 40 名患有便秘，40 名成功治疗便秘，评估了几个可测量的参数。使用逻辑回归构建了一个基于这些腹部 X 射线参数预测便秘状态的模型。使用 ROC 曲线的 AUC 分析评估模型准确性。
最具预测性的模型包括盲肠直径、测量的总粪便长度、直肠内粪便长度以及患者的年龄和性别。ROC 曲线下面积测量的准确性非常好，为 0.87。我们计算了腹部 X 射线上单个参数的截止值，包括总粪便长度大于 33.4cm、盲肠直径大于 3.7cm 和直肠内粪便长度大于 5.9cm。
我们根据腹部 X 射线的客观测量确定了准确可靠的标准，以区分有便秘和无便秘的患者。这些标准可用于客观评估无便秘史但有排尿症状的儿童的便秘状况。进一步的研究将确定这些标准是否可以预测治疗反应。
