Table 2.

Comparison of experimental population technologies for investigating cellular populations (SPIO, superparamagnetic iron oxide labelling; RH, ionizing radiation hazard limits frequency of imaging; DOSI, diffuse optical spectroscopic imaging; MRI, magnetic resonance imaging; PET, positron emission tomography; CT, computed tomography; CTC, circulating tumour cell; asterisk (*) denotes capability might be limited or not yet widely demonstrated to provide quantitative accuracy; dagger (†) denotes resolution at depth in tissue—see [49] for discussion of dependence of spatial resolution on depth). Order-of-magnitude resolution estimates are based on assuming densely packed cells with a cell diameter of ~10 microns.