| Abstrakt: |
Objectives: The aim of this paper is to present in a simple concise and clear manner the computer tomography (CT) perfusion technique using a 64-multi-slice CT (MSCT) and to discuss the main clinical applications. Materials and Methods: The CT protocol included: unenhanced CT scan to locate the prostate, intravenous administration of non-ionic iodinated contrast medium using a power injector (volume-100 ml, rate 5ml/s), scanning in CINE mode (cranio-caudal coverage - 40 mm, continuous exposure for 40 seconds) with a 10 seconds delay after beginning of injection, followed by ten additional 1-second scans in axial mode, with a 15-second interval to quantify the amount of contrast medium that filtered into the interstitial compartment. Perfusion CT examination was followed by a standard thoraco-abdomino-pelvic examination; a report was issued according to our daily clinical practice. The patients received doses (DLP - Dose Length Product) ranged between 1000 and 1500 mGy·cm, depending on their age and weight. Analysis of source images was performed on a workstation using a dedicated software. Results: Colored functional maps and quantitative measurements were obtained for the following parameters: Permeability Surface-area product (PS), Blood Volume (BV), Mean Transit Time (MTT), Blood Flow (BF), Contrast Arrival Delay (IRF T0), Time to Peak (TTP), Transit Time to Impulse Residue Function Peak (Tmax). Placing ROI's in femoral artery, normal and abnormal prostate tissue, we obtained graphs with contrast-enhancement curves and tables with specific CT perfusion parameters. Conclusions: Perfusion CT represent an imaging diagnostic tool that may be used in prostate cancer, allowing an easy and quick assessment of the functional changes, providing informations about in vivo tumor vascularity and guidance for histopathological correlation if biopsy is scheduled. Moreover, this technique may be performed in cases where MRI is contraindicated. [ABSTRACT FROM AUTHOR] |
