Purpose MRI and single-photon emission computed tomography (SPECT) provide complimentary information which could aid in the diagnosis of various diseases. However, acquiring images from both modalities can been problematic. Until recently, SPECT systems could not be integrated with MRI systems due to the use of photomultiplier tubes which do not function in high magnetic fields. The development...

We present systematic characterization of a photoacoustic imaging system optimized for rapid, high-resolution tomographic imaging of small animals. The system is based on a 128-element ultrasonic transducer array with a 5-MHz center frequency and 80% bandwidth shaped to a quarter circle of 25 mm radius. A 16-channel data-acquisition module and dedicated channel detection electronics enable capt...

To test the feasibility of applying ultrasonic elastography on small animal oncology models, experiments were performed in vitro and in situ on murine mammary lesions induced exogenously by tumor cell line 66.3. In vitro studies involved three 1-week-old excised tumors embedded in a phantom block with ultrasonic properties similar to those of soft biologic tissues. In situ studies involved five...

Magnetic resonance imaging (MRI) provides high-resolution morphological images useful in diagnostic radiology to differentiate between normal and abnormal/pathological states in tissues. More recently, emerging developments in MRI have added a functional/physiological dimension to anatomical images. Electron paramagnetic resonance (EPR), a magnetic resonance technique similar to nuclear magneti...

Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging in biological research. Small animal imaging with bioluminescence has been validated recently in a variety of research models and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene delivery and/or expre...

In vivo Cerenkov luminescence imaging is a rapidly growing molecular imaging research field based on the detection of Cerenkov radiation induced by beta particles when traveling though biological tissues. We investigated theoretically the possibility of enhancing the number of the detected Cerenkov photons in the near infrared (NIR) region of the spectrum. The analysis is based on applying a ph...

We describe a novel macroscopic fluorescent imaging technique called angular domain fluorescence imaging (ADFI) applicable to the detection of fluorophores embedded in biological tissues. The method exploits the collimation detection capabilities of an angular filter array (AFA). The AFA uses the principle of acceptance angle filtration to extract minimally scattered photons emitted from fluoro...

Clustering analysis (CA) and principal component analysis (PCA) were applied to dynamic Cerenkov luminescence images (dCLI). In order to investigate the performances of the proposed approaches, two distinct dynamic data sets obtained by injecting mice with (32)P-ATP and (18)F-FDG were acquired using the IVIS 200 optical imager. The k-means clustering algorithm has been applied to dCLI and was i...

H. F. Wehrl, M. S. Judenhofer, P. Martirosian, F. Maier, G. Reischl, F. Schick, and B. J. Pichler Laboratory for Preclinical Imaging of the Werner Siemens-Foundation, Department of Radiology, University of Tuebingen, Tuebingen, BW, Germany, Section on Experimental Radiology, Department of Radiology, University of Tuebingen, Tuebingen, BW, Germany, Radiopharmacy and PET-Center, Department of Rad...

UNLABELLED The purpose of this study was to investigate whether a correction for annihilation photon attenuation in small objects such as mice is necessary. The attenuation recovery for specific organs and subcutaneous tumors was investigated. A comparison between different attenuation correction methods was performed. METHODS Ten NMRI nude mice with subcutaneous implantation of human breast ...