Optimization of Energy Level in Abdominal Organs with Single-source Dual Energy CT
Background/Objectives: To find optimal keV using Optimal CNR when using Single source dual energy CT
Methods/Statistical analysis: Clinical studies were collected the data targeting 132 patients doing abdomen exam by using GE Discovery 750 HDCT. To measure each organ keV using Optimal CNR Tool supported from ADW 4.6. Slice thickness and Interval 2.5mm / 2.5mm, Detector coverage was 40mm, pitch was 0.984:1 and Rotation Time 0.7sec, Algorithm set soft, and clinic set 70sec scan time after 120cc contrast injection. Statistic was used PASW Statistics 18.
Findings: All abdomen organs shows the optimal CNR between 60 and 75keV, over 99.2% was included the range of 65~70keV among the rest. Also, as the comparison the average and the median, the result shows under 66~68keV range. And the mode was between 65 and 69keV.
CNR average and standard deviation of each organ were measured liver 8.45 ± 9.93, spleen 8.77 ± 2.96, kidney 13.08 ± 18.06, bile duct 4.16 ± 5.80, pancreas 7.59 ± 8.88, bladder 2.38 ± 2.99, intra-abdominal fat -5.43 ± 7.48, supra abdominal fat -6.02 ± 8.84, muscle 4.16 ± 5.80, aorta 13.17 ± 16.17,lumbar spine 15.38 ± 22.43, and pelvis 18.27 ± 16.84. As doing One-Way ANOBA for evaluating the keV variation following patient’s age, BMI and contrast injection speed, the result shows no significance because intergroup P-value was all higher than 0.05.
Improvements/Applications: When doing abdomen exam using SSDE CT, if using properly to get images applied optimal CNR within the 65~70 keV range. Also, the optimal CNR is 66~68 keV.
- Eliahou R, Hidas G, Duvdevani M, Sosna J. Determination of renal stone composition with dual-energy computed tomography: an emerging application. Seminars in ultrasound, CT, and MR. 2010 Aug;31(4):315-20.
- Macari M, Spieler B, Kim D, Graser A, Megibow AJ, Babb J, et al. Dual-source dual-energy MDCT of pancreatic adenocarcinoma: initial observations with data generated at 80 kVp and at simulated weighted-average 120 kVp. AJR American journal of roentgenology. 2010 Jan;194(1):W27-32.
- Karcaaltincaba M, Aktas A. Dual-energy CT revisited with multidetector CT: review of principles and clinical applications. Diagnostic and interventional radiology (Ankara, Turkey). 2011 Sep;17(3):181-94.
- Johnson TR, Krauss B, Sedlmair M, Grasruck M, Bruder H, Morhard D, et al. Material differentiation by dual energy CT: initial experience. European radiology. 2007 Jun;17(6):1510-7.
- Bamberg F, Dierks A, Nikolaou K, Reiser MF, Becker CR, Johnson TR. Metal artifact reduction by dual energy computed tomography using monoenergetic extrapolation. European radiology. 2011 Jul;21(7):1424-9.
- Amano Y, Ishihara M, Hayashi H, Gemma K, Kawamata H, Amano M, et al. Metallic artifacts of coronary and iliac arteries stents in MR angiography and contrast-enhanced CT. Clinical imaging. 1999 Mar-Apr;23(2):85-9.
- Torikoshi M, Tsunoo T, Sasaki M, Endo M, Noda Y, Ohno Y, et al. Electron density measurement with dual-energy x-ray CT using synchrotron radiation. Physics in medicine and biology. 2003 Mar 7;48(5):673-85.
- Wang L, Liu B, Wu XW, Wang J, Zhou Y, Wang WQ, et al. Correlation between CT attenuation value and iodine concentration in vitro: discrepancy between gemstone spectral imaging on single-source dual-energy CT and traditional polychromatic X-ray imaging. Journal of medical imaging and radiation oncology. 2012 Aug;56(4):379-83.
- Fletcher JG, Takahashi N, Hartman R, Guimaraes L, Huprich JE, Hough DM, et al. Dual-energy and dual-source CT: is there a role in the abdomen and pelvis? Radiologic clinics of North America. 2009 Jan;47(1):41-57.
- Graser A, Johnson TR, Chandarana H, Macari M. Dual energy CT: preliminary observations and potential clinical applications in the abdomen. European radiology. 2009 Jan;19(1):13-23.
- Kalva SP, Sahani DV, Hahn PF, Saini S. Using the K-edge to improve contrast conspicuity and to lower radiation dose with a 16-MDCT: a phantom and human study. Journal of computer assisted tomography. 2006 May-Jun;30(3):391-7.
- Sudarski S, Apfaltrer P, W. Nance J J, Schneider D, Meyer M, Schoenberg SO, et al. Optimization of keV-settings in abdominal and lower extremity dual-source dual-energy CT angiography determined with virtual monoenergetic imaging. European journal of radiology. 2013 Oct;82(10):e574-81.
Abstract Views: 14
PDF Views: 0