When P-gp is upregulated, 11C]phenytoin might be a more sensitive tracer to detect changes in P-gp function than a strong substrate tracer.
As inflammation detection has become the major concept in atherosclerosis PET/CT imaging, a more sensitive tracer is still to be found.
For these reasons, [C]CB184 was evaluated as a potentially more sensitive PET tracer.
Several PET tracers are proving more sensitive than conventional imaging techniques for early detection of lymph node and bone metastases.
Again, we found that the estimates of the individual compartmental rate parameters were far more sensitive to this than the calculated tracer influx.
On the other hand, tracer tests may be more sensitive to heterogeneous elements present in the reservoir because of the convective nature of the flow test.
A full kinetic analysis of the dynamic PET and blood data would also be of interest, but this approach, whilst potentially more sensitive to small changes in bone clearance of tracer, is also limited in practicality.
A more sensitive method is to assess in vivo aromatase inhibition with tracer techniques [ 60, 61].
However, semi-quantitative approaches are simple to apply, and whilst less informative and more sensitive to experimental conditions, the use of NA offers a useful surrogate descriptor of tracer retention when datasets are acquired under an identical experimental set-up and protocol.
