Hyperpolarized gas imaging

I found while googling this interesting new uses of the MRI:

•Until recently, MRI images of the lung had been very difficult to obtain due to the low hydrogen content of the lung.
•Hyperpolarized gas imaging requires that the patient inhale a laser-polarized noble or inert gas (xenon or helium). The polarized gas makes it possible for MRI to image the lung.
• This technique has already been successful at imaging the lungs of patients with emphysema and has clearly identified the regions of low ventilation that occur due to the disease .

Fasting before PET scan

This PET was acquired from a male patient suffering from a metastatic disease ,
The first (Upper row) was taken after breakfast but he told the invistigator that he was fasting,
PET scan showed minor tumor activity in mediastinal area while CT showed large masses,
Four days later PET was performed again (the patient was fasting that time) which showed the realistic tumor metabolism and multiple metastasis in lung , liver ......(click the image for larger view).