求翻译：下肢静脉曲张256层CT采用延迟5 s经足背静脉以2ml/s速度注射50ml(非离子型350 mgI/ml对比剂稀释10%)可获得满意的诊断图像是什么意思？

Varicose 256-slice CT using delayed 5 s via dorsal foot vein injection with 2ml/s speed 50ml (non-ionic contrast media 350 mgI/ml 10% dilution) can obtain satisfactory diagnosis images