Characterizing a photoacoustic and fluorescence imaging platform for preclinical murine longitudinal studies

Abstract

. Significance To effectively study preclinical animal models, medical imaging technology must be developed with a high enough resolution and sensitivity to perform anatomical, functional, and molecular assessments. Photoacoustic (PA) tomography provides high resolution and specificity, and fluorescence (FL) molecular tomography provides high sensitivity; the combination of these imaging modes will enable a wide range of research applications to be studied in small animals. Aim We introduce and characterize a dual-modality PA and FL imaging platform using in vivo and phantom experiments. Approach The imaging platform’s detection limits were characterized through phantom studies that determined the PA spatial resolution, PA sensitivity, optical spatial resolution, and FL sensitivity. Results The system characterization yielded a PA spatial resolution of in the transverse plane and in the longitudinal axis, a PA sensitivity detection limit not less than that of a sample with absorption coefficient , an optical spatial resolution of in the vertical axis and in the horizontal axis, and a FL sensitivity detection limit not concentration of IR-800. The scanned animals displayed in three-dimensional renders showed high-resolution anatomical detail of organs. Conclusions The combined PA and FL imaging system has been characterized and has demonstrated its ability to image mice in vivo , proving its suitability for biomedical imaging research applications.

In vivo noninvasive systemic myography of acute systemic vasoactivity in female pregnant mice

“…Deionized and degassed water at 36 °C temperature is used as acoustic coupling medium. The TriTom system spatial resolution in the transverse plane is 173 ± 17 μm and 640 ± 120 μm in the longitudinal axis with an absorption coefficient sensitivity detection limit of 0.258 cm -1 , and imaging speed of 38 s 22 .…”

“…Another spherical-view system has a reported spatial resolution of 200 μm (lateral and axial) and large FOV (80 mm) 21 . However, the limited view aperture of the system requires a helical scanning scheme for whole-body imaging, reducing the temporal resolution to 45 s. The TriTom spherical-view photoacoustic tomography system uses a 360° rotation to capture a 3 cm 3 volume with a spatial resolution of 173 ± 17 μm (transverse plane) that can image vessel diameters down to ~180 mm in 38 s 22 .…”

Spatiotemporal image reconstruction to enable high-frame-rate dynamic photoacoustic tomography with rotating-gantry volumetric imagers

“…⊳ Increment outer loop iteration end while 4.1 3D PACT Imaging System Specifications for Experimental and Numerical Studies The TriTom preclinical imaging system 19,51 developed by PhotoSound was employed for the experimental studies and emulated for the numerical in-silico studies. It integrates photoacoustic (PA) and fluorescence (FL) imaging modalities, harnessing their individual strengths.…”

Real-time dual-modal photoacoustic and fluorescence small animal imaging

“…Therefore, it is of great value to explore the integration of PAI with FLI for live animal studies. Several studies have reported their efforts to combine PAI results with FLI results for small animal research [19] , [20] , [21] , [22] . These integrated systems either performed PAI and FLI in a sequential way or take long time to finish dual modal imaging, which are suitable for monitoring relatively slow changes.…”