New method for 3D parametric visualization of contrast-enhanced pulmonary perfusion MRI data.

Three-dimensional (3D) dynamic contrast-enhanced magnetic resonance imaging (3D DCE-MRI) has been proposed for the assessment of regional perfusion. The aim of this work was the implementation of an algorithm for a 3D parametric visualization of lung perfusion using different cutting planes and volume rendering. Our implementation was based on 3D DCE-MRI data of the lungs of five patients and five healthy volunteers. Using the indicator dilution theory, the regional perfusion parameters, tissue blood flow, blood volume and mean transit time were calculated. Due to the required temporal resolution, the volume elements of dynamic MR data sets show a reduced spatial resolution in the z-direction. Therefore, perfusion parameter volumes were interpolated. Linear interpolation and a combination of linear and nearest-neighbor interpolation were evaluated. Additionally, ray tracing was applied for 3D visualization. The linear interpolation algorithm caused interpolation errors at the lung borders. Using the combined interpolation, visualization of perfusion information in arbitrary cutting planes and in 3D using volume rendering was possible. This facilitated the localization of perfusion deficits compared with the coronal orientated source data. The 3D visualization of perfusion parameters using a combined interpolation algorithm is feasible. Further studies are required to evaluate the additional benefit from the 3D visualization.