Magnetic resonance imaging (MRI) provides superior soft-tissue contrast, allowing high-resolution anatomical imaging, which can be further improved with contrast agents. The development of molecular targeted contrast agents now provides the research community with high resolution molecular imaging. Fiducial markers can be applied to animals prior to PET/SPECT and MRI imaging to allow coregistration of the functional and anatomical information provided by the respective imaging technologies. Research applications of MRI include stem cell and pathophysiologic imaging, including atherosclerosis.
The CMGI provides MRI imaging on a Biospec 7 T (300 MHz) horizontal bore system located at the NMR facility adjacent to the CMGI. The NMR facility is a core campus recharge unit operated and maintained by three Ph.D. staff scientists. Two CMGI Imaging Research Associates are fully trained in the use of the Biospec 7T to provide imaging for CMGI clients.
Two gradient sets are available for the Biospec 7T: a 125 mm i.d. set capable of ~ 10 g/cm gradient strength, and a smaller, 60 mm i.d. (microimaging) set capable of strengths up to 100 g/cm. There are two Bruker volume proton imaging coils (70 mm i.d.) for the larger gradient set and two 35 mm i.d. coils for the smaller set. A wide variety of non-magnetic animal holders have been constructed in-house for MRI experiments, along with various customized equipment for animal anesthesia, ventilation, maintenance of body temperature, etc. Physiological (respiratory, cardiac) gating can be performed as necessary with the Bruker PhysiTool interface to the Paravision MRI software.
MODALITY
MODEL
MANUFACTURER
RESOLUTION
PET
Focus 20
Siemens
~1.3mm
PET
P4
Siemens
~1.8mm
PET
microPETI
Custom-built
~1.8mm
SPECT
microSPECT
Siemens
~1mm
CT
microCAT II
Siemens
25-150 um
CT
microCT
Custom-built
~ 300um
MRI
Biospec 7T
Bruker
50-250 um
Ultrasound
Sequoia
Siemens
~ 120 um
Optical
IVIS 100
Xenogen
~ 2mm
Autoradiography
Storm 860
Amersham Biosciences
50-100 um
For additional information:
Louie AY, Huber MM, Ahrens ET, et al. In vivo visualization of gene expression using magnetic resonance imaging. Nat Biotechnol; 18:321-5, 2000
Cherry SR. In vivo molecular and genomic imaging: new challenges for imaging physics. Phys Med Biol; 49:R13-48, 2004.
Tyszka JM, Fraser SE, Jacobs RE. Magnetic resonance microscopy: recent advances and applications. Curr Opin Biotechnol; 16:93-9, 2005
Sosnovik DE, Weissleder R. Emerging concepts in molecular MRI. Curr opin biotechnol; 18:4-10, 2007.
Magnetic resonance imaging (MRI) provides superior soft-tissue contrast, allowing high-resolution anatomical imaging, which can be further improved with contrast agents. The development of molecular targeted contrast agents now provides the research community with high resolution molecular imaging. Fiducial markers can be applied to animals prior to PET/SPECT and MRI imaging to allow coregistration of the functional and anatomical information provided by the respective imaging technologies. Research applications of MRI include stem cell and pathophysiologic imaging, including atherosclerosis.
Two gradient sets are available for the Biospec 7T: a 125 mm i.d. set capable of ~ 10 g/cm gradient strength, and a smaller, 60 mm i.d. (microimaging) set capable of strengths up to 100 g/cm. There are two Bruker volume proton imaging coils (70 mm i.d.) for the larger gradient set and two 35 mm i.d. coils for the smaller set. A wide variety of non-magnetic animal holders have been constructed in-house for MRI experiments, along with various customized equipment for animal anesthesia, ventilation, maintenance of body temperature, etc. Physiological (respiratory, cardiac) gating can be performed as necessary with the Bruker PhysiTool interface to the Paravision MRI software.