Department of Medical Imaging, Children's Hospital of Eastern Ontario, 401 Smyth Rd., Ottawa, ON, K1H 8L1, Canada.
University of Ottawa, Ottawa, ON, Canada.
Pediatr Radiol. 2019 Sep;49(10):1313-1319. doi: 10.1007/s00247-019-04460-y. Epub 2019 Jul 9.
The pediatric reproductive organs are optimally imaged with a full bladder. The filling of the bladder, however, often leads to significant delay in diagnosis and can subject the patient to invasive bladder catheterization. As the key imaging feature in ovarian torsion is unilateral ovarian enlargement, we suspected that a torsed ovary is large enough to be visualized even if the bladder is not well distended.
The purpose of this study was to retrospectively investigate if clinically suspected adnexal torsion can be excluded based on non-visualization of the ovaries on transabdominal ultrasound (US) with a non-distended bladder in pediatric patients.
This retrospective study comprised 349 girls (1-19 years old) between Jan. 1, 2013, and July 30, 2018. Three hundred and forty-one of the girls were referred to transabdominal US to assess for adnexal torsion and/or appendicitis, and the ovaries were initially not visualized on US. Their bladders were subsequently filled and rescanned with a distended bladder showing the ovaries. Ovarian volumes and time between US scans were documented. The ratio of the volume of the larger ovary to the smaller one was calculated. Nine girls had surgically proven adnexal torsion and a preoperative transabdominal US with a non-distended bladder. There was an overlap of one girl between the two groups. The negative predictive value (NPV), positive predictive value (PPV), and sensitivity and specificity for exclusion of adnexal torsion based on non-visualization of the ovaries on US with a non-distended bladder were calculated.
One of the girls (1/341) who had a US study done with a non-distended bladder in which the ovaries were not visualized had a positive diagnosis of adnexal torsion. In eight of the nine girls who had surgically proven adnexal torsion, the torted ovary was identified with a non-distended bladder. The NPV and PPV for exclusion of adnexal torsion with a non-distended bladder was 1.0 and 0.8, respectively. The specificity and sensitivity were 99.4% and 88.9%, respectively. The mean and median time difference between the initial scan and the scan after bladder filling was 105.1 min (standard deviation [SD] -65.8) and 89.0 min (interquartile range [IQR]- 59.0, 130.5), respectively.
Non-visualization of the ovaries with a non-distended bladder on transabdominal US study can help exclude clinically suspected adnexal torsion, alleviating the need for bladder filling and prolonging the wait time in the emergency department. Inclusion of non-visualization of the ovaries as one of the features in a predictive score for adnexal torsion should be considered.
儿科生殖器官在充盈膀胱时能得到最佳成像。然而，充盈膀胱常常会导致诊断显著延迟，并使患者遭受侵入性膀胱插管。由于卵巢扭转的关键影像学特征是单侧卵巢增大，我们怀疑即使膀胱未充分充盈，扭转的卵巢也大到可以被看到。
本研究旨在回顾性研究在儿童患者中，经腹部超声（US）检查在非充盈膀胱时无法显示卵巢是否可以排除临床疑似附件扭转。
这项回顾性研究纳入了 2013 年 1 月 1 日至 2018 年 7 月 30 日期间的 349 名女孩（1-19 岁）。其中 341 名女孩因疑似附件扭转或阑尾炎而接受经腹部 US 检查，最初在 US 上未显示卵巢。随后为她们充盈膀胱并再次扫描，此时可见卵巢。记录卵巢体积和两次 US 扫描之间的时间。计算较大卵巢和较小卵巢体积的比值。9 名女孩经手术证实患有附件扭转，且术前接受了经腹部 US 检查，当时膀胱未充盈。两组中各有 1 名重叠的女孩。计算在经腹部 US 检查时在非充盈膀胱下无法显示卵巢时排除附件扭转的阴性预测值（NPV）、阳性预测值（PPV）以及敏感性和特异性。
在因疑似附件扭转或阑尾炎而接受经腹部 US 检查且膀胱未充盈时，有 1 名女孩（341 名中的 1 名）的 US 检查显示卵巢未显示，该名女孩的诊断为附件扭转。在 9 名经手术证实患有附件扭转的女孩中，8 名女孩的扭转卵巢在膀胱未充盈时被识别。用未充盈膀胱排除附件扭转的 NPV 和 PPV 分别为 1.0 和 0.8。特异性和敏感性分别为 99.4%和 88.9%。初始扫描和膀胱充盈后扫描之间的平均和中位数时间差分别为 105.1 分钟（标准差 [SD]-65.8）和 89.0 分钟（四分位距 [IQR]-59.0，130.5）。
经腹部 US 检查在非充盈膀胱下无法显示卵巢有助于排除临床疑似附件扭转，从而减轻充盈膀胱的需要并延长急诊等待时间。应考虑将未显示卵巢作为附件扭转预测评分的特征之一。
