Department of Emergency Medicine, University of Rochester, Galisano Children's Hospital, Rochester, NY.
Acad Emerg Med. 2013 Aug;20(8):795-800. doi: 10.1111/acem.12185.
Computed tomography (CT) with enteric contrast is frequently used to evaluate children with suspected appendicitis. The use of CT with intravenous (IV) contrast alone (CT IV) may be sufficient, however, particularly in patients with adequate intra-abdominal fat (IAF).
The authors aimed 1) to determine the ability of radiologists to visualize the normal (nondiseased) appendix with CT IV in children and to assess whether IAF adequacy affects this ability and 2) to assess the association between IAF adequacy and patient characteristics.
This was a retrospective 16-center study using a preexisting database of abdominal CT scans. Children 3 to 18 years who had CT IV scan and measured weights and for whom appendectomy history was known from medical record review were included. The sample was chosen based on age to yield a sample with and without adequate IAF. Radiologists at each center reread their site's CT IV scans to assess appendix visualization and IAF adequacy. IAF was categorized as "adequate" if there was any amount of fat completely surrounding the cecum and "inadequate" if otherwise.
A total of 280 patients were included, with mean age of 10.6 years (range = 3.1 to 17.9 years). All 280 had no history of prior appendectomy; therefore, each patient had a presumed normal appendix. A total of 102 patients (36.4%) had adequate IAF. The proportion of normal appendices visualized with CT IV was 72.9% (95% confidence interval [CI] = 67.2% to 78.0%); the proportions were 89% (95% CI = 81.5% to 94.5%) and 63% (95% CI = 56.0% to 70.6%) in those with and without adequate IAF (95% CI for difference of proportions = 16% to 36%). Greater weight and older age were strongly associated with IAF adequacy (p < 0.001), with weight appearing to be a stronger predictor, particularly in females. Although statistically associated, there was noted overlap in the weights and ages of those with and without adequate IAF.
Protocols using CT with IV contrast alone to visualize the appendix can reasonably include weight, age, or both as considerations for determining when this approach is appropriate. However, although IAF will more frequently be adequate in older, heavier patients, highly accurate prediction of IAF adequacy appears challenging solely based on age and weight.
计算机断层扫描（CT）联合肠内对比常用于疑似阑尾炎患儿的评估。然而，单独使用静脉（IV）对比的 CT（CT IV）可能就足够了，特别是对于那些有足够的腹腔内脂肪（IAF）的患者。
作者旨在 1）确定放射科医生使用 CT IV 检查儿童时能够观察到正常（无病变）阑尾的能力，并评估 IAF 充足性是否会影响这种能力，以及 2）评估 IAF 充足性与患者特征之间的关联。
这是一项回顾性的 16 中心研究，使用腹部 CT 扫描的预存数据库。纳入了年龄在 3 至 18 岁之间，进行 CT IV 扫描且有记录可查的既往阑尾切除术病史的患者。基于年龄选择样本，以获得 IAF 充足和不充足的样本。各中心的放射科医生重新阅读其站点的 CT IV 扫描，以评估阑尾可视化和 IAF 充足性。如果有任何量的脂肪完全环绕盲肠，则将 IAF 归类为“充足”，否则归类为“不足”。
共纳入 280 例患者，平均年龄为 10.6 岁（范围=3.1 至 17.9 岁）。所有 280 例患者均无既往阑尾切除术史；因此，每位患者都有一个假定的正常阑尾。102 例（36.4%）患者的 IAF 充足。通过 CT IV 观察到正常阑尾的比例为 72.9%（95%置信区间[CI]：67.2%至 78.0%）；IAF 充足和不足的患者中，正常阑尾的比例分别为 89%（95% CI：81.5%至 94.5%）和 63%（95% CI：56.0%至 70.6%）（95% CI 差异比例=16%至 36%）。更大的体重和更大的年龄与 IAF 充足性呈强烈相关（p<0.001），体重的影响似乎更大，尤其是在女性中。尽管在统计学上存在关联，但在 IAF 充足和不足的患者中，体重和年龄存在重叠。
单独使用 IV 对比 CT 来观察阑尾的方案可以合理地将体重、年龄或两者都作为确定该方法适用的考虑因素。然而，尽管在年龄较大、体重较重的患者中，IAF 更常是充足的，但仅基于年龄和体重对 IAF 充足性进行高度准确的预测似乎具有挑战性。
