MRI detection of tumor in mouse lung using partial liquid ventilation with a perfluorocarbon-in-water emulsion

Transverse relaxation time (T2)-weighted 1H-MRI of mouse lungs has been performed using partial liquid ventilation (PLV) with a perfluorocarbon (PFC)-in-water emulsion as a contrast modality for lung MRI. Significant sensitivity enhancement in MRI of mouse lungs has been demonstrated with the protocol. The results show that the T2 value in lung is approximately proportional to the infusion dose up to a dose of 5 ml/kg body weight (BW) (4.5 g PFC/kg BW) and becomes essentially constant beyond this dosage. T2 maps of lungs have been calculated and T2 in lungs is in the range of 10–35 ms with this technique, which is an order of magnitude greater than the T2 value of mouse lungs without using a PFC-in-water emulsion. T2-weighted 1H-MR images of mouse lungs have been obtained with good quality under our experimental conditions. We have applied this technique to detect tumors in mouse lungs. Our technique can detect small lung tumors of B16 melanoma, about 1 mm in diameter, in mice. With its significant MR sensitivity enhancement and technical simplicity, T2-weighted 1H-MRI using PLV with PFC-in-water emulsion offers a promising approach to investigate lung cancers using rodent models.