Imaging of lung vascularization and perfusion in children. 
Imaging techniques to evaluate lung perfusion are continuously evolving.  Chest film is still the first step.  Spiral CT has revolutionized chest imaging in children, MRI is still progressing and thanks to it, multiplanar abilities will probably take a great importance in the future.  The accessibility of the machine is still a limiting factor.  Angiography is now restricted to interventional procedures.