PRECLINICAL APPLICATIONS
OptoSonics' preclinical photoacoustic computed tomography (PAT) apparatus allows in vivo imaging of laboratory mice for use in pharmaceutical drug development and evaluation. The brief presentations below highlight the capabilities of our instrumentation in preclinical studies.
An anesthetized mouse is placed within a transparent plastic sampling bowl suspended at the top of the detector array. Optical excitation of the mouse anatomy is provided by an OPO tunable laser, covering near-infrared wavelengths ranging from 680 to 950 nm, at approximately 20 mJ/pulse. Typically, the laser is tuned to 800 nm, which is the isosbestic point for absorption by oxygenated and de-oxygenated hemoglobin. This allows unparalleled visualization of vascular structures for pharmaceutical studies.
Internal mouse anatomy is visualized through hemoglobin absorption, as shown in the following movie. Note that the total scan time was only 12 seconds. Used in combination with wavelength selection, OptoSonics' rapid scanning technology allows for multiple types of dynamic drug absorption studies.
By collecting image volumes at two distinct wavelengths, the differential volume can be used to visualize the uptake of a molecular probe (such as indocyanine green, ICG). The color image (below, right) shows detection of 3 μM ICG using differential absorption of two mouse volumes, at wavelengths of 800 and 835 nm.
