High-resolution pulmonary arterio- and venography using multiple-bolus multiphase 3D-Gd-mRA

Area of Science:

• Medical Imaging
• Cardiovascular Radiology
• Pulmonary Medicine

Background:

• Accurate visualization of pulmonary vasculature is crucial for diagnosing vascular pathologies.
• Existing imaging methods may have limitations in spatial resolution or radiation exposure.

Purpose of the Study:

• To develop and demonstrate a selective, high-resolution imaging technique for pulmonary arteries and veins.
• To improve the detection of vascular pathologies in the lungs.

Main Methods:

• Acquisition of time-resolved, three-dimensional (3D) gadolinium-enhanced magnetic resonance angiography (3D-Gd-MRA) using an ultrashort 3D fast low-angle shot (FLASH) sequence.
• Synchronized infusion of two gadolinium chelate boli with acquisition of alternating data sets to create temporally anti-correlated arterial and venous phases.
• Application of correlation analysis to separate arterial and venous signals, achieving high spatial resolution (1.9 x 1.4 x 2 mm³).

Main Results:

• High-quality pulmonary arteriograms and venograms were generated, with complete elimination of background signal.
• In 7 out of 8 patients, there was no venous contamination of the arterial phase or vice versa.
• Reliable assessment of pulmonary artery and vein patency down to segmental vessels was achieved.

Conclusions:

• The combination of ultrafast multiphase 3D-Gd-MRA, dual-bolus injection, and correlation analysis provides high-resolution pulmonary arterio- and venograms.
• This novel imaging strategy offers a promising alternative to traditional X-ray angiography for pulmonary vascular assessment.