Biomedical subjects
Publications and source records attributed to Paolo Pavone.
The purpose of this paper is to illustrate the fundamentals of contrast-enhanced MR angiography, its recent advances and future prospects. The factors influencing contrast-enhanced MR angiography are identified. The main acquisition and timing techniques are described with emphasis on their advantages and drawbacks.
PURPOSE: To compare two different techniques to improve vessels opacification in coronary angiography with multislice CT (MSCT) scanner. MATERIALS AND METHODS: Thirty consecutive patients were divided into two groups. In group 1, the synchronisation was obtained administering 20 ml of cm at 4 ml/s during a dynamic monitoring sequence. In group 2, the real time monitoring of the main bolus was used to trigger the scan. The CT angiography was performed in both groups by administering 100 ml of cm at 4 ml/s, with MSCT scanner and the following parameters: collimation 16 x 0.75 mm, rotation time 0.42 s, retrospective ECG gating. Three regions of interest were created in order to measure attenuation at: 1) ascending aorta (ROI 1); 2) descending aorta (ROI 2); 3) pulmonary artery (ROI 3). Attenuation was also measured at the origin of the main coronary arteries and their larger branches. RESULTS: The average time/density curve showed lower enhancement in group 1 compared to group 2 in the first 4 s and 7 s in ROI 1 and ROI 2, respectively (p<0.05). The maximum enhancement value were 342 HU and 347 HU for group 1 in ROI 1 and ROI 2, and 356 HU and 352 HU for group 2 in ROI 1 and ROI 2, respectively. The attenuation at the origin of the main coronary arteries was higher in group 2 than in group 1 (p<0.05). CONCLUSIONS: Real time monitoring technique allows to use 20% less cm and provides better and more homogeneous enhancement.