Continuous Wave FMT
We have been developing several prototypes for advanced fluorescence molecular tomography instruments. Two that have been published operate on CW illumination and detection technology as follows.
First Generation FMT System
The left image shows a Fluorescence Molecular Tomography (FMT) imager chamber prototype using a fixed source-detector design. The instrument specifics have been published in Medical Physics 29: 803-809 (2002). The image on the right depicts a combined FMT/MRI scan imaging cathepsin B expression levels in 9L gliosarcomas stereotactically implanted into unilateral brain hemispheres of nude mice. a) Axial MR slices of an animal implanted with a tumor, which is shown in green after gadolinium enhancement. b) Superposition of the MR axial slice passing through the tumor (a) onto the corresponding FMT slice after appropriately translating the MR image to the actual dimensions of the FMT image. c) fluorescence image of the same axial brain section demonstrating a marked fluorescent probe activation, congruent with the tumor position identified by gadolinium-enhanced MRI and FMT.
Second generation FMT system
This system uses a planar geometry with a fixed source setup and a direct lens-coupled CCD camera. FMT and conventional reflectance imaging can be performed simultaneously. This implementation allows for superior FMT imaging characteristics compared to the cylindrical geometry used above. Currently the resolution achieved with system in small animals is below 1mm (~0.7mm).
For details on 1st generation FMT see Ntziachristos et al, Nat. Med. 8(7): 757-760 (2002)
For details on 2nd generation FMT see Graves et al, Med. Phys. 30 (5): 901-911 (2003)