Riccabona Michael, Fritz Gerald A, Schöllnast Helmut, Schwarz Thomas, Deutschmann Michael J, Mache Christoph J
Department of Radiology, Division of Pediatric Radiology, University Hospital Graz, Auenbruggerplatz 9, A-8036 Graz, Austria.
Radiology. 2005 Jul;236(1):276-83. doi: 10.1148/radiol.2361040158. Epub 2005 Jun 13.
To prospectively evaluate accuracy of three-dimensional (3D) ultrasonography (US) for assessment of relative renal size in infants and children with hydronephrosis.
Informed consent was obtained from parents and also from children who were older than 8 years. Study was approved by ethics committee. Two-dimensional (2D) US, 3D US, and scintigraphy were performed in 40 patients with hydronephrosis (age range, neonate to 16 years; seven girls, 33 boys) without acute renal disease. Twenty patients also underwent magnetic resonance (MR) urography. US and MR urography were performed by one experienced pediatric radiologist; 3D US and MR urographic volume calculations were performed by specifically trained radiologists. Three-dimensional US was performed with integrated 3D volume probes or external system based on electromagnetic positioning devices. At 2D US, kidney volume was calculated with application of ellipsoid equation. At MR urography and 3D US, real renal parenchymal volume was calculated with subtraction of dilated collecting system. Split renal function was assessed with static renal scintigraphy. Three-dimensional US results were graded with respect to image quality and compared with results of 2D US, scintigraphy, and MR urography by using mean difference percentage and standard deviation of the difference. All investigations were performed with blinding. Inter- and intraobserver variability were calculated with coefficient of variation.
In 76 of 80 kidneys, 3D US image of diagnostic quality was obtained. Three-dimensional US volume measurements compared well with MR urographic measurements (mean difference, -2.5% +/- 7.8 [standard deviation] vs 25.8% +/- 32.2 for 2D US) and with scintigraphically assessed split renal function (mean difference, 1.2% +/- 9.2 vs 15.9% +/- 43.8 for 2D US). Intra- and interobserver variability were +/-6.4% and +/-9.9%, respectively.
Initial experience with renal 3D US indicates that it is an accurate method for assessment of renal parenchymal volume and relative renal size, provided there is no acute renal disease.
前瞻性评估三维（3D）超声检查（US）在评估肾积水婴幼儿及儿童相对肾大小方面的准确性。
获得了患儿父母以及8岁以上患儿本人的知情同意。研究经伦理委员会批准。对40例无急性肾病的肾积水患者（年龄范围为新生儿至16岁；7例女孩，33例男孩）进行二维（2D）US、3D US和闪烁扫描。20例患者还接受了磁共振（MR）尿路造影检查。US和MR尿路造影由一名经验丰富的儿科放射科医生进行；3D US和MR尿路造影容积计算由经过专门培训的放射科医生进行。采用基于电磁定位装置的集成3D容积探头或外部系统进行3D US检查。在2D US检查时，应用椭圆体方程计算肾脏容积。在MR尿路造影和3D US检查时，通过减去扩张的集合系统来计算实际肾实质容积。采用静态肾闪烁扫描评估分肾功能。对3D US结果进行图像质量分级，并通过平均差异百分比和差异标准差与2D US、闪烁扫描和MR尿路造影结果进行比较。所有检查均在盲态下进行。采用变异系数计算观察者间和观察者内的变异性。
在80个肾脏中的76个中，获得了诊断质量的3D US图像。3D US容积测量结果与MR尿路造影测量结果（平均差异为-2.5%±7.8[标准差]，而2D US为25.8%±32.2）以及闪烁扫描评估的分肾功能（平均差异为1.2%±9.2，而2D US为15.9%±43.8）比较良好。观察者内和观察者间的变异性分别为±6.4%和±9.9%。
肾3D US的初步经验表明，在无急性肾病的情况下，它是评估肾实质容积和相对肾大小的准确方法。
