Optimization of the Contrast Mixture Ratio for Simultaneous Direct MR and CT Arthrography: an in Vitro Study.
- Author:
Ja Young CHOI
1
;
Heung Sik KANG
;
Sung Hwan HONG
;
Joon Woo LEE
;
Na Ra KIM
;
Woo Sun JUN
;
Sung Gyu MOON
;
Jung Ah CHOI
Author Information
- Publication Type:Original Article ; In Vitro
- Keywords: Magnetic resonance (MR), arthrography; Computed tomography (CT), arthrography; Gadolinium; Computed tomography (CT), contrast media
- MeSH: *Arthrography; Contrast Media/*administration & dosage; Gadolinium/administration & dosage/*diagnostic use; Iohexol/administration & dosage/*analogs & derivatives/diagnostic use; *Magnetic Resonance Imaging; Meglumine/administration & dosage/*diagnostic use; Organometallic Compounds/administration & dosage/*diagnostic use; Phantoms, Imaging; *Tomography, X-Ray Computed
- From:Korean Journal of Radiology 2008;9(6):520-525
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: This study was designed to determine the optimal mixture ratio of gadolinium and iodinated contrast agent for simultaneous direct MR arthrography and CT arthrography. MATERIALS AND METHODS: An in vitro study was performed utilizing mixtures of gadolinium at six different concentrations (0.625, 1.25, 2.5, 5.0, 10 and 20 mmol/L) and iodinated contrast agent at seven different concentrations (0, 12.5, 25, 37.5, 50, 75 and 92-99.9%). These mixtures were placed in tissue culture plates, and were then imaged with CT and MR (with T1-weighted sequences, proton-density sequences and T2-weighted sequences). CT numbers and signal intensities were measured. Pearson's correlation coefficients were used to assess the correlations between the gadolinium/iodinated contrast agent mixtures and the CT numbers/MR signal intensities. Scatter diagrams were plotted for all gadolinium/iodinated contrast agent combinations and two radiologists in consensus identified the mixtures that yielded the optimal CT numbers and MR signal intensities. RESULTS: The CT numbers showed significant correlation with iodinated contrast concentrations (r = 0.976, p < 0.001), whereas the signal intensities as measured on MR images showed a significant correlation with both gadolinium and iodinated contrast agent concentrations (r = -484 to -0.719, p < 0.001). A review of the CT and MR images, graphs, and scatter diagram of 42 combinations of the contrast agent showed that a concentration of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was the best combination for simultaneous CT and MR imaging. CONCLUSION: A mixture of 1.25 mmol/L gadolinium and 25% iodinated contrast agent was found to be optimal for simultaneous direct MR arthrography and CT arthrography.
