Ces radiol. 2012, 66(1):23-29

Dual-source CT angiography of abdominal aorta and lower limb arteries: possibilities of radiation dose and contrast material reductionOriginal article

Jan Baxa¹, Jiří Ferda¹, Petr Duras¹, Jiří Moláček², Petr Havránek¹, Hynek Mírka¹

¹ Klinika zobrazovacích metod LF UK a FN, Plzeň

² Chirurgická klinika LF UK a FN, Plzeň

Aim: Our work was focused on the feasibility of CT angiography of abdominal aorta and lower limbs using new generation of dual-source CT with a high pitch factor, concerning on the reduction of radiation exposure and the amount of administered contrast agent.

Methods: In the prospective study were examined 29 patients with clinical signs, or known disability of lower limbs arteries. The examinations were performed on the Somatom Definition Flash (Siemens, Germany) using collimation 128 × 0.6 mm, high tube rotation speed (0.28 s/rotation) and a higher pitch factor of 1.55).Amount of contrast agent (60 to 70 ml) was applied at 5 ml/s, the timing of acquisition was based on results of the test bolus monitoring (10 ml) in the popliteal arteries. Evaluation of image quality was based on visual assessment and determination of density in different parts of the arterial system.

Results: In all cases were achieved a high display quality of the aorta, pelvic, femoral and popliteal arteries by visual assessment and also determination of luminal density (aorta - 456.3 HU, groin - 507.3 HU, k nee - 554.3). In the region of the distal leg and ankle occurred in 3 people in suboptimal quality due to overrun of bolus. Only in one case, the distal region leg was uninterpretable. The average level density at ankle level was 367.7 HU.
The average radiation exposure was low - CTDIvol 2.40, 1.79 mSv effective dose.

Conclusion: The preliminary results of our prospective study showed the possibility of performing CT angiography of the lower limbs in "high-pitch" mode. Despite the very low radiation dose and the amount of applied contrast agent was achieved a high diagnostic quality of the aorta, pelvic, femoral, popliteal and proximal crural arteries. This test method should be especially recommended for people at high risk of contrast nephropathy and for young people.

Keywords: CT angiography, subrenal aorta, lower limbs arteries, high-pitch mode, dual-source CT

Grants and funding:

Práce byla podpořena výzkumným projektem MSM 0021620819.

Accepted: January 25, 2012; Published: March 1, 2012  Show citation