Multislice CT angiography: Optimization of scan parameters in a vascular phantom.

Citation
C. Funke et al., Multislice CT angiography: Optimization of scan parameters in a vascular phantom., ROFO-F RONT, 172(11), 2000, pp. 927-933
Citations number
16
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging
Journal title
ROFO-FORTSCHRITTE AUF DEM GEBIET DER RONTGENSTRAHLEN UND DER BILDGEBENDEN VERFAHREN
ISSN journal
14389029 → ACNP
Volume
172
Issue
11
Year of publication
2000
Pages
927 - 933
Database
ISI
SICI code
1438-9029(200011)172:11<927:MCAOOS>2.0.ZU;2-I
Abstract
Purpose: The aim of this study is to determine the optimal scan parameters for the evaluation of experimental vascular stenoses with a multislice-heli cal CT. Material and Methods: A vascular phantom consisting of four tubes w ith an inner diameter of 8 mm and with experimental stenoses of 50%, 75% an d 90% was scanned in different tube orientations using a multislice-CT scan ner (LightSpeed QX/i, GE, Milwaukee, USA). Examinations were performed with increasing collimations (1.25-5mm), tube currents (100-300mA) and two diff erent table speeds (0.75 HQ mode and 1.5 HS mode). Results: The most exact measurements were obtained in tubes angulated parallel to the scan directio n with a collimation of 2.5 mm in the HQ mode (7.5 mm/rot.). An almost equi valent accuracy was obtained in the HS mode (15 mm/rot.) with a collimation of 2.5 mm when higher tube currents (300 mA) were employed. The degree of stenoses was overestimated when the tube was angulated perpendicular to the z-axis. Conclusion: Multislice-CT provides a good detection rate of vascul ar stenoses especially at 0 degrees and also at 45 degrees angulation in th e HQ mode. The use of the HS mode with higher tube currents allows scanning of longer distances with almost identical accuracy.