Siddaiah Mahadevaswamy, Krishna Satheesh, McInnes Matthew D F, Quon Jeffrey S, Shabana Wael M, Papadatos Demetri, Schieda Nicola
1 The Ottawa Hospital, The University of Ottawa, 1053 Carling Ave, Ottawa, ON K1Y 4E9, Canada.
AJR Am J Roentgenol. 2017 Sep;209(3):604-610. doi: 10.2214/AJR.17.17814. Epub 2017 Jul 5.
The purpose of this study was to evaluate the ability of ultrasound (US) to characterize hyperattenuating cysts detected as indeterminate hyperattenuating renal lesions on unenhanced and single phase enhanced CT.
A total of 107 consecutive homogeneously hyperattenuating renal lesions underwent gray-scale and Doppler US at our institution between 2010 and 2013. Two radiologists who were unaware of the final diagnosis retrospectively evaluated US images for visibility and diagnosis (simple cyst, intermediate complexity cyst, cystic or solid mass showing internal flow on Doppler US, or indeterminate). A third radiologist assessed lesion size, location, and distance to skin on CT and US. US visibility was compared using chi-square and independent t tests. Consensus US interpretation was compared with reference standard diagnoses, and accuracy for diagnosis of hyperattenuating cysts was tabulated.
Mean lesion size ± SD was 20 ± 16 mm (range, 6-96 mm) and mean distance to skin on CT was 62 ± 25 mm (range, 18-125 mm). In all, 89.7% (96/107) of the lesions were visible on US, including all lesions that were 15 mm or larger. Nonvisible lesions were smaller than visible ones (10.0 ± 3.6 mm vs 20.7 ± 16.3 mm, p = 0.03) regardless of location (p > 0.05). CT overestimated lesion distance to skin compared with US (46.6 ± 18.6 mm, p < 0.001). Final diagnoses for US visible lesions (n = 96) were hyperattenuating cyst (n = 66), Bosniak IIF cyst (n = 13), and cystic or solid neoplasm (n = 15); two patients were lost to follow-up. Of the 66 hyperattenuating cysts, 54 (81.8%) appeared as simple cysts on US with sensitivity and specificity for diagnosis of hyperattenuating cyst of 81.8% (95% CI, 75.6-84.3%) and 92.9% (95% CI, 78.1-98.7%), respectively. The other 12 (18.2%) hyperattenuating cysts appeared complex. Two of the 13 Bosniak IIF lesions were incorrectly classified as simple cysts with US. Including the 11 (10%) nonvisible lesions reduced sensitivity and specificity for diagnosis of hyperattenuating cyst to 73.0% (95% CI, 66.9-75.9%) and 89.7% (95% CI, 74.2-97.2%), respectively.
US can further characterize hyperattenuating cysts presenting as indeterminate hyperattenuating renal lesions on CT in the majority of cases.
本研究旨在评估超声（US）对在未增强及单相增强CT上表现为不确定的高密度肾病变的高密度囊肿的特征性诊断能力。
2010年至2013年间，我院对107例连续的均匀高密度肾病变进行了灰阶和多普勒超声检查。两名不知最终诊断结果的放射科医生对超声图像进行回顾性评估，以确定其可视性和诊断结果（单纯囊肿、中等复杂囊肿、在多普勒超声上显示内部血流的囊性或实性肿块，或不确定）。第三名放射科医生评估病变在CT和超声上的大小、位置及距皮肤的距离。使用卡方检验和独立t检验比较超声可视性。将超声的一致性解读与参考标准诊断结果进行比较，并列出高密度囊肿诊断的准确性。
病变平均大小±标准差为20±16mm（范围6 - 96mm），CT上病变距皮肤的平均距离为62±25mm（范围18 - 125mm）。总体而言，89.7%（96/107）的病变在超声上可见，包括所有15mm或更大的病变。无论位置如何（p>0.05），不可见病变均小于可见病变（10.0±3.6mm对20.7±16.3mm，p = 0.03）。与超声相比，CT高估了病变距皮肤的距离（46.6±18.6mm，p<0.001）。超声可见病变（n = 96）的最终诊断为高密度囊肿（n = 66）、博斯尼亚克IIF级囊肿（n = 13）和囊性或实性肿瘤（n = 15）；两名患者失访。在66个高密度囊肿中，54个（81.8%）在超声上表现为单纯囊肿，诊断高密度囊肿的敏感性和特异性分别为81.8%（95%CI，75.6 - 84.3%）和92.9%（95%CI，78.1 - 98.7%）。另外12个（18.2%）高密度囊肿表现复杂。13个博斯尼亚克IIF级病变中有2个在超声上被错误分类为单纯囊肿。将11个（10%）不可见病变纳入后，诊断高密度囊肿的敏感性和特异性分别降至73.0%（95%CI，66.9 - 75.9%）和89.7%（95%CI，74.2 - 97.2%）。
在大多数情况下，超声可进一步明确CT上表现为不确定的高密度肾病变的高密度囊肿的特征。
