'Two is better than one'--probes for dual-modality molecular imaging.

Molecular or personalised medicine is the future of patient management and healthcare, and molecular imaging plays a key role towards this goal. However, amongst molecular imaging techniques, no single modality is perfect and sufficient to gain all the necessary information. For instance, optical fluorescence imaging is difficult to quantify--especially in tissue more than a few millimetres in depth within a subject; magnetic resonance imaging (MRI) has superb resolution but low sensitivity and positron emission tomography (PET) has very high sensitivity but poor resolution.