- Evaluation of tracer kinetic models for quantification of P-glycoprotein function using (R)-[11C]verapamil and PET. Lubberink, M., Luurtsema, G., van Berckel, B.N., Boellaard, R., Toornvliet, R., Windhorst, A.D., Franssen, E.J., Lammertsma, A.A. J. Cereb. Blood Flow Metab. (2007)