Technical aspect of CT angiography of lower extremities.

ABSTRACT

Objective: To assess the less invasive technique of CT angiography for evaluation of lower extremity arteries with nonionic water soluble iodinated contrast medium. Methods: One hundred thirty patients underwent a CT angiography of lower extremity using smart prep technique above the iliac creast 1 inch. and the following parameters Helical, Rotation time 0.8 seconds, Rotation length full, Detector configuration 16X1.25 mm, Helical thickness 1.25, Pitch 1.3751, Speed 27.50 mm/rotation, Beam collimation 20 mm, Image interval 1.0 mm, Gantry tilt 0.0, SFOV large, X-ray energy 140 kV, 260 mA. Results: The data of CT Acquisition and Contrast Medium Parameters were Scanning coverage (mm) 1040 ฑ 88, Scanning duration (sec) 33+ 5, Number of transverse sections 1063+ 348 iodine dose (g) 89.8+ 5.3, Concentration of contrast medium(mg/ml) 356.7+ 24.4, Volume of contrast medium (ml) 120+ 0, Contrast medium injector rate (ml/sec) 4+ 0, Injection duration (sec) 30+ 0, Scanning -to-injection duration ratio 1.08+ 0.2, Delay between contrast medium initiation and scanning (sec) 26+ 5.3. Conclusion: The conventional study for lower extremity arteries is conventional angiography which is invasive method. This method required admission and absolute bed rest at least 8-12 hours after procedure. The CT angiography takes advantage over conventional angiography, including 3D volumetric analysis, minimally invasive vascular opacification and depiction of mural calcium. The fastest and more slices of current generation of 16 slices multidetector CT scanner is possible to study entire length of lower extremities.