|
|
||||||||
Original Research |
1 Department of Diagnostic Radiology, Graduate School of Medical Sciences,
Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
2 Department of Radiological Technology, School of Health Sciences, Kumamoto
University, Kumamoto, Japan.
OBJECTIVE. The purpose of our study was to compare aortic CT angiography performed at a low tube voltage and reduced dose of contrast material with standard-voltage, standard-contrast-dose CT angiography.
SUBJECTS AND METHODS. We evaluated 74 patients for aortic disease on MDCT angiography (collimation, 16 x 1.5 mm; beam pitch, 0.9). In 36 patients, we used the standard tube voltage (120 kVp) and a contrast dose of 100 mL (300 mg I/mL) (protocol 1), and in the remaining 38 patients we applied a reduced tube voltage (90 kVp) and a contrast dose of 40 mL (300 mg I/mL) (protocol 2). The patients' weights, CT attenuation of the aorta, visualization of the celiac axis and renal artery, and graininess and streak artifacts on transverse CT scans were evaluated and recorded for each data set. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were also measured. For statistical analysis, we used the two-tailed Student's t test and logistic regression; agreement between measurements recorded independently by two blinded reviewers was assessed using Cohen kappa statistics.
RESULTS. In both protocols a negative correlation was seen between
patient weight and CT attenuation. In three protocol 1 patients weighing more
than 70 kg, CT attenuation was less than 200 H. No difference was seen between
the two protocols with respect to mean attenuation of the aorta (p =
0.13) or visualization of the celiac axis and renal artery (p = 0.35
and 0.60, respectively). Although the SNR and CNR were significantly higher in
protocol 1 than in protocol 2, qualitative evaluation of graininess and streak
artifacts showed no statistically significant difference (p = 0.15
and 0.48, respectively). Interobserver agreement for quality assessments was
within an acceptable range (
= 0.42-0.80).
CONCLUSION. Low-contrast and low-voltage scans are appropriate for lighter patients (< 70 kg in body weight) with aortic disease. Moreover, this method is particularly valuable for follow-up studies of heavier patients (> 70 kg) with renal dysfunction.
Keywords: aortography arteriography contrast media CT radiation dose tube voltage
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
Z. Szucs-Farkas, M. Semadeni, S. Bensler, M. A. Patak, G. von Allmen, P. Vock, and S. T. Schindera Endoleak Detection with CT Angiography in an Abdominal Aortic Aneurysm Phantom: Effect of Tube Energy, Simulated Patient Size, and Physical Properties of Endoleaks Radiology, May 1, 2009; 251(2): 590 - 598. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. H. de Vries, H. W. Venema, J. Florie, C. Y. Nio, and J. Stoker Influence of Tagged Fecal Material on Detectability of Colorectal Polyps at CT: Phantom Study Am. J. Roentgenol., October 1, 2008; 191(4): W181 - W189. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. T. Boll, E. M. Merkle, E. K. Paulson, R. A. Mirza, and T. R. Fleiter Calcified Vascular Plaque Specimens: Assessment with Cardiac Dual-Energy Multidetector CT in Anthropomorphically Moving Heart Phantom Radiology, October 1, 2008; 249(1): 119 - 126. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-Y. Yang, Y.-F. Chen, C.-W. Lee, A. Huang, Y. Shen, C. Wei, and H.-M. Liu Multiphase CT Angiography versus Single-Phase CT Angiography: Comparison of Image Quality and Radiation Dose AJNR Am. J. Neuroradiol., August 1, 2008; 29(7): 1288 - 1295. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. T. Boll, E. M. Merkle, E. K. Paulson, and T. R. Fleiter Coronary Stent Patency: Dual-Energy Multidetector CT Assessment in a Pilot Study with Anthropomorphic Phantom Radiology, June 1, 2008; 247(3): 687 - 695. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |