Comparison of diagnostic quality and accuracy in color-coded versus gray-scale DCE-MR imaging display
ABSTRACT PurposeThe purpose of this study was to evaluate the diagnostic value and tumor-vascular display properties (microcirculation) of
two different functional MRI post-processing and display (color and gray-scale display) techniques used in oncology.
Materials and methodsThe study protocol was approved by the IRB and written informed consent was obtained from all patients. 38 dynamic contrast
enhanced magnetic resonance imaging (DCE-MRI) data sets of patients with malignant pleural-mesothelioma were acquired and
post-processed. DCE-MRI was performed at 1.5tesla with a T1-weighted 2D gradient-echo-sequence (TR 7.0ms, TE 3.9ms, 15
axial slices, 22 sequential repetitions), prior and during chemotherapy. Subtracting first image of contrast-enhanced-dynamic
series from the last, produced gray-scale images. Color images were produced using a pharmacokinetic two-compartment model.
Eight raters, blinded to diagnosis, by visual assessment of post-processed images evaluated both diagnostic quality of the
images and vasculature of the tumor using a rating scale ranging from −5 to +5. The scores for vasculature were assessed by
correlating with the maximum amplitude of the total-tumor-ROI for accuracy.
ResultsColor coded images were rated as significantly higher in diagnostic quality and tumor vascular score than gray-scale images
(p < 0.001, 0.005). ROI signal amplitude analysis and vascular ratings on color coded images were better correlated compared
to gray-scale images rating (p < 0.05).
ConclusionColor coded images were shown to have higher diagnostic quality and accuracy with respect to tumor vasculature in DCE-MRI,
therefore their implementation in clinical assessment and follow-up should be considered for wider application.
- American Journal of Neuroradiology 05/2010; 31(5):925-7. DOI:10.3174/ajnr.A2077 · 3.59 Impact Factor
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ABSTRACT: To evaluate low-dose contrast-enhanced magnetic resonance angiography (CE-MRA) at high temporal and spatial resolution for imaging of abdominal vascular structures. Contrast-enhanced magnetic resonance angiography (TWIST [time-resolved angiography with interleaved stochastic trajectories]) was performed in 8 male New Zealand white rabbits at 3 T using a prototype 32-channel coil. Gadoteridol (Gd-HP-DO3A, ProHance; Bracco Imaging SpA, Milan, Italy) and the high-relaxivity agent gadobenate dimeglumine (Gd-BOPTA, MultiHance; Bracco Imaging SpA), each at a dose of 0.04 mmol/kg body weight, were used in an intraindividual comparison. Quantitative analysis of contrast-to-noise ratio (CNR) was performed in regions of interest placed in the aorta and the adjacent tissues. The image quality in the aorta, external iliac artery, and vena cava was categorized by 2 independent blinded readers from excellent (1) to poor (3). A significantly (P < 0.001) higher CNR was obtained with gadobenate dimeglumine. The improved CNR led to a better delineation of the external iliac arteries. Qualitative rating showed the image quality to be excellent for gadobenate dimeglumine and adequate for gadoteridol. Time-resolved CE-MRA performed at 3 T with a 32-channel volume coil can be improved using the high-relaxivity agent gadobenate dimeglumine, which increases quality and quantity of vessel enhancement.Journal of computer assisted tomography 09/2010; 34(5):678-83. DOI:10.1097/RCT.0b013e3181e359c2 · 1.41 Impact Factor
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ABSTRACT: Cerebral aneurysm is a cerebrovascular disorder in which weakening in the walls of brain blood vessels causing a swelling or dilation of blood vessels. The disease is also called intracranial aneurysms and usually occurs around the arteries at the base of the brain called the Circle of Willis. To date, methods of diagnosis of cerebral aneurysms are still done manually by performing direct observation of medical imagery from CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) images. In addition, medical images are also shown in monochrome thereby increasing the difficulties in making observations. Therefore we need a more effective detection method for detection of aneurysms because presently this process is highly dependent on the subjectivity of the observer. This study was aimed to design a method for detection of cerebral aneurysms by using 2D DSA imaging technique, based on the calculation of Time to Peak (TTP) and Time Duration (TD) of flow of contrast agent in the blood vessels. This method was designed and simulated using Matlab software. The results of detection of 2-dimensional image segmentation of blood vessels were visualized by color system based on a specific index. The simulation showed good results. Visualization of blood vessels based on Time to Peak (TTP) calculation produced an image in which arteries and veins were segmented with different color. Visualization based on Time Duration (TD) calculation produced an image where an aneurysm can be shown in different color than normal blood vessels.Electrical Engineering and Informatics (ICEEI), 2011 International Conference on; 07/2011