Hansson Kerstin, Häggström Jens, Kvart Clarence, Lord Peter
Department of Biomedicine, Division of Diagnostic Imaging and Clinical Pathology, Swedish University of Agricultural Sciences, Box 7029, SE-750 07 Uppsala, Sweden.
Vet Radiol Ultrasound. 2005 Mar-Apr;46(2):122-30. doi: 10.1111/j.1740-8261.2005.00024.x.
The vertebral heart size (VHS) method by Buchanan is based on anatomic landmarks. A potential source of variation among observers is differences in the selection of measurement points. The objective was to test variability between observers with different levels of training in thoracic radiology and small animal clinical practice. Fifty sets of thoracic radiographs of cavalier King Charles spaniels, were divided into five groups; (Normal) normal cardiopulmonary structures, (I) slight cardiomegaly, (II) moderate cardiomegaly, (II +) moderate cardiomegaly with congestive heart failure, and (III +) severe cardiomegaly with congestive heart failure. Cardiomegaly was confirmed by echocardiography to be caused by mitral regurgitation because of myxomatous mitral valve disease. Sixteen observers representing four levels of experience (four observers/level) evaluated the radiographs; (1) European Diplomates in Veterinary Diagnostic Imaging, (2) Experienced small animal clinicians, (3) Trainees in small animal clinical practice (4) Veterinary students. Almost identical mean VHS values were found among the four experience levels for each of the five groups of radiographs with a low coefficient of variation, range 1.5-3.2%. Mean difference among the 16 observers was 1.05 +/- 0.32 vertebrae (v). Mean difference among individuals in each observer group was approximately 0.5 v for all but the groups of trainees were the difference was 0.6-0.9 v. The conclusion is that VHS method for heart size is independent of observer experience but dependent of individual observers selection of reference points and transformation of long and short axis dimensions into VHS units.
布坎南提出的脊椎心脏大小（VHS）测量方法是基于解剖学标志点的。观察者之间存在差异的一个潜在来源是测量点选择的不同。本研究的目的是测试在胸部放射学和小动物临床实践方面接受不同程度培训的观察者之间的变异性。将50组查理士王小猎犬的胸部X光片分为五组：（正常）心肺结构正常、（I）轻度心脏肥大、（II）中度心脏肥大、（II +）伴有充血性心力衰竭的中度心脏肥大、（III +）伴有充血性心力衰竭的重度心脏肥大。通过超声心动图确认心脏肥大是由黏液瘤性二尖瓣疾病导致的二尖瓣反流引起的。16名代表四个经验水平的观察者（每个水平4名观察者）对X光片进行了评估，分别为：（1）欧洲兽医诊断影像学专科医师、（2）经验丰富的小动物临床医生、（3）小动物临床实践培训学员、（4）兽医专业学生。在五组X光片中，四个经验水平的观察者所测得的平均VHS值几乎相同，变异系数较低，范围为1.5 - 3.2%。16名观察者之间的平均差异为1.05±0.32个椎体（v）。除培训学员组差异为0.6 - 0.9 v外，每个观察者组内个体之间的平均差异约为0.5 v。结论是，心脏大小的VHS测量方法与观察者经验无关，但取决于个体观察者对参考点的选择以及将长轴和短轴尺寸转换为VHS单位的方式。
