To assess the diagnostic quality of low dose (100kV) CTA, study by using ultra low contrast medium volume (30mL), for thoracic and abdominal aorta evaluation.
Sixty-seven patients with thoracic or abdominal vascular disease underwent MDCT study using a 256 slices scanner, with low dose radiation protocol (100 kV;automated tube current modulation) and low contrast medium volume (30mL; 4mL/s). ... [Show full abstract] Density measurements were performed on ascending, arch, descending thoracic aorta, anonymous branch, abdominal aorta, renal and common iliac arteries. Radiation dose exposure (dose-length product/DLP) was calculated. A control group of 35 patients with thoracic or abdominal vascular disease were evaluated with standard CTA protocol (120kV;automated tube current modulation;contrast medium:80mL).
In all patients we correctly visualized and evaluated main branches of the thoracic and abdominal aorta. No difference of density measurements was achieved between low kV protocol (mean attenuation value of thoracic aorta 304 HU;abdominal 343 HU;renal arteries 331 HU) and control group (mean attenuation value of thoracic aorta 320 HU;abdominal 339;renal arteries 303 HU). Radiation dose exposure in low kV protocol was significantly different between thoracic and abdominal low kV study (490 DLP;324 DLP) and the control group (thoracic DLP 1032;abdomen DLP 1078).
Low-kV protocol may provide a diagnostic performance, comparable with that of the standard protocol, decreasing radiation dose exposure and contrast material volume amount. Advances in knowledge: Low-kV setting protocol combined with ultra low contrast agent volume (30 mL), by using new multidetector-row CT scanners, represents a feasible diagnostic tool to significantly reduce the radiation dose delivered to patients and to preserve renal function, maintaining also adequate diagnostic quality images in assessment of aorta.