Cammillo Roberto Giovanni Leopoldo Talei Franzesi, Presenter: Nothing to Disclose

Davide Ippolito MD, Abstract Co-Author: Nothing to Disclose

Pietro Andrea Bonaffini MD, Abstract Co-Author: Nothing to Disclose

Davide Fior MD, Abstract Co-Author: Nothing to Disclose

Pietro Allegranza MD, Abstract Co-Author: Nothing to Disclose

Sandro Sironi MD, Abstract Co-Author: Nothing to Disclose

To assess the diagnostic quality and the radiation dose exposure of low-kV CT angiography study (100kV), by using ultra low contrast medium volume (40mL), for thoracic and abdominal aorta disease.

From July 2011 to November 2013, 89 patients (33 women;mean age 65.7years;range,35-83years;BMI<30),with thoracic or abdominal aortic disease,were prospectively examined with 256-MDCT scan(Brilliance iCT;Philips) using low-dose protocol(100kV;automated tube current modulation) and ultra low-contrast volume(40mL;4mL/s;350mgI/mL).For the evaluation of ascending aorta, an ECG-gated retrospective protocol was performed. A control group of 61 patients (21women;mean age 66.4years;range,34-86years), who underwent on the same scanner standard CT-angiography protocol (120kV;350mAs),with standard contrast volume(80mL), was also evaluated.Density measurements were performed manually drawing a region of interest(ROI) on lumen of ascending aorta,arch,descending and abdominal aorta,renal arteries and common iliac arteries.The radiation dose exposure(dose-length product,DLP) was also calculated for both groups.Then,the obtained data were compared and statistically analyzed.

In all patients we could correctly visualize and evaluate lumen and walls of thoracic and abdominal aorta and main arterials branches. No significant difference of density measurements was achieved between low-kV group (mean attenuation value of thoracic aorta 321HU,abdominal aorta 332HU and renal arteries 338HU) and control group (mean value of thoracic aorta 316HU,abdominal aorta 327HU and renal arteries 307HU).The radiation dose exposure was significantly lower(p<0,05) in low-kV protocol(mean DLP thoracic 490mGy*cm;abdominal 335mGy*cm) than in control group(mean DLP thoracic 820mGy*cm;abdominal 952mGy*cm),with an overall reduction of 41% in the thoracic and 65% for abdominal study.

Low-kV CT angiography protocol maintain a high diagnostic performance similar to standard protocol, with a significant decrease of the radiation dose exposure as well as the contrast material volume, reducing also the risk of contrast-induced nephropathy.

Low-kV and low-contrast volume CT-angiography allows to significant reduce the radiation exposure, maintaining high diagnostic quality and reducing the risk of renal impairment.

Talei Franzesi, C, Ippolito, D, Bonaffini, P, Fior, D, Allegranza, P, Sironi, S, CT-angiography with Low kV and Low Contrast Medium Volume Using a 256 Multi-detector CT Scanner in the Evaluation of Thoracic and Abdominal Aorta Disease: Diagnostic Efficacy and Radiation Dose Reduction.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045489.html