Assessment of pulmonary perfusion in a single shot using SEEPAGE

Abstract

Purpose: To present a single-shot perfusion imaging sequence that does not require contrast agents or a subtraction of a tag and a control image to create the perfusionweighted contrast. The proposed method is based on SEEPAGE. Materials and Methods:Experiments with healthy volunteers were performed to qualitatively and quantitatively obtain pulmonary perfusion values in coronal as well as sagittal orientation. In addition, a first experiment with a lung cancer patient was performed to explore the potentials of SEEPAGE in a clinical application. Results:All experiments clearly showed a perfusionweighted contrast, providing clinical quality images with high spatial resolution. The quantified perfusion rates were consistent in the different imaging orientations and covered the interval of 1.00 -4.00 mL/min/mL. In addition, the gravitational dependence of pulmonary perfusion, the influence of adiabatic pulse duration on signal intensity, and the tracer saturation effect were examined. In the patient examination the presented technique provided additional information of the lung deficiency compared to a conventional anatomical image.Conclusion: SEEPAGE has proved to be a robust and reproducible technique for obtaining perfusion-weighted images in a single measurement and for quantifying pulmonary perfusion using an additional reference scan. Furthermore, the proposed method shows promise for future clinical application.

Quantitative lung perfusion evaluation using fourier decomposition perfusion MRI

“…As seen in Table , all FD perfusion values were found to be within the range expected from literature . The standard deviations seen in Table are relatively high, but this could be accounted for by the inclusion of semi‐large vessels and the inherent heterogeneity of blood flow in the lung.…”

“…As in Fischer et al , we argue that 2· T exp · f from Eq. also corresponds to the voxel filling factor.…”

“…Given perfect separation of blood from background, we modify the work of Buxton et al , Pracht et al , and Fischer et al and describe the signal intensity in a pixel in the perfusion map as: where Im perfusion is the FD perfusion map, c blood an image signal constant converting blood volume into steady state signal intensity and v the blood volume in mL. The factor 2 is due to an assumed symmetry in Fourier space (for details see the Appendix).…”

Pulmonary perfusion imaging using MRI: clinical application

“…No change was seen along an isogravitational plane. These results were confirmed for volunteers lying on their back [15]. …”

Pulmonary MR angiography and perfusion imaging—A review of methods and applications

“…SEEPAGE completely supresses the backgr protons flowing into the field of view return signal. This has the advantage of requiring no subtraction (so no mis-registration) and allows rapid acquisitions within short breath-holds (24). All of these spin-labelling techniques are by nature slice selective methodologies, and therefore limited in terms of lung volume coverage.…”