The visibility scores of most anatomic structures were significantly superior with the90kv(mean scroe of,3.10). The differences in rating scores did not reach statistical significance only for the peripheral vessels,the cardiac contours and the carina.

• 绝大多数解剖结构在90千伏时得分最高(平均得分3.；10)；除了在心影轮廓、气管隆突和外围纹理方面以外；其余部位均有明显统计学差异。