Byl Kevin M, Kruger John M, Kinns Jennifer, Nelson Nathan C, Hauptman Joe G, Johnson Cheri A
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA.
Am J Vet Res. 2010 Mar;71(3):374-80. doi: 10.2460/ajvr.71.3.374.
To compare accuracy of estimates of cystolith size obtained by means of plain radiography, double-contrast cystography, ultrasonography, and computed tomography.
30 canine cystoliths ranging from 1 to 11 mm in diameter with various mineral compositions.
A bladder phantom model was created by filling a rubber balloon with saline (1% NaCl) solution and positioning it on top of a 2% gelatin cushion at the bottom of a water-filled 4-quart container. Cystoliths were individually placed in the bladder phantom and imaged by each of the 4 techniques. For each image, cystolith size was measured by 2 radiologists with computerized calipers, and size estimates were compared with actual cystolith size.
Mean cystolith size estimates obtained by means of radiography, cystography, and computed tomography did not differ significantly from each other. However, for ultrasonographic images, mean +/- SD difference between actual and estimated cystolith size (2.95 +/- 0.73 mm) was significantly higher than mean difference for radiographic, cystographic, and computed tomographic images. For ultrasonography, mean +/- SD percentage overestimation in cystolith size was 68.4 +/- 51.5%.
Results indicated that measurements of cystolith size obtained by means of ultrasonography may overestimate the true size. This suggests that cystolith size estimates obtained by means of ultrasonography should be interpreted with caution whenever cystolith size may influence patient management.
比较通过X线平片、双重对比膀胱造影、超声检查和计算机断层扫描获得的膀胱结石大小估计值的准确性。
30颗犬膀胱结石，直径1至11毫米，具有不同的矿物质成分。
通过向橡胶气球中填充盐水（1%氯化钠）溶液，并将其放置在装满水的4夸脱容器底部的2%明胶垫上，创建一个膀胱模型。将膀胱结石分别放入膀胱模型中，并用这4种技术进行成像。对于每张图像，由2名放射科医生使用计算机卡尺测量膀胱结石大小，并将大小估计值与实际膀胱结石大小进行比较。
通过X线平片、膀胱造影和计算机断层扫描获得的膀胱结石大小平均估计值之间没有显著差异。然而，对于超声图像，实际和估计的膀胱结石大小之间的平均±标准差差异（2.95±0.73毫米）显著高于X线平片、膀胱造影和计算机断层扫描图像的平均差异。对于超声检查，膀胱结石大小的平均±标准差高估百分比为68.4±51.5%。
结果表明，通过超声检查获得的膀胱结石大小测量值可能高估了真实大小。这表明，每当膀胱结石大小可能影响患者管理时，对通过超声检查获得的膀胱结石大小估计值应谨慎解读。
