Errors in Radiographic Measurements Caused by Variations in the Table Top∕Bucky Tray Distance

The distance between the table top and the Bucky tray varies between radiographic rooms in most x-ray departments. A potential difference of 8% or more in the degree of magnification of radiographic images was found in five Memphis hospitals. Articles on measurement of kidneys, intracranial volume, sella turcica, etc. should specify the distance used to establish the charts.