Noninvasive gadolinium-enhanced three dimensional computed tomography coronary angiography

Area of Science:

• Radiology
• Medical Imaging
• Cardiovascular Imaging

Background:

• Gadolinium (Gd)-based contrast agents are used in various angiographic studies.
• Their diagnostic efficacy and image quality in coronary computed tomography angiography (CTA) remain under-investigated.

Purpose of the Study:

• To evaluate the image quality of Gd-based contrast agents in coronary CTA.
• To compare the attenuation of Gd and iodinated contrast agents.

Main Methods:

• Phantom study comparing serial dilutions of Gd and iodinated agents using 64-slice multirow detector CT (MDCT) and e-speed scanners.
• Evaluation of 35 patients undergoing Gd-enhanced CTA, measuring aortic CT attenuation and grading coronary artery visualization.
• Substudy involving four patients with borderline renal insufficiency using a 50:50 Gd and iodinated contrast admixture.

Main Results:

• Phantom study demonstrated near-identical CT attenuation (CTHU) for various dilutions of Gd and iodine (r(2) > or = 0.997).
• Mean CTHU of the aorta with contrast ranged from 93 to 125 HU.
• Coronary CTA image quality grading: 2 Grade III (diagnostic), 9 Grade II, and 24 Grade I images, with an average image quality score of 1.35.

Conclusions:

• Gd-enhanced contrast medium provides adequate enhancement for diagnostic evaluation of coronary arteries with current CT systems.
• Advancements in multirow detector CT scanner technology are expected to further improve image quality.