Characterization of Brown Adipose Tissue in a Diabetic Mouse Model with Spiral Volumetric Optoacoustic Tomography

Abstract

Diabetes is associated with a deterioration of the microvasculature in brown adipose tissue (BAT) and with a decrease in its metabolic activity. Multispectral optoacoustic tomography has been recently proposed as a new tool capable of differentiating healthy and diabetic BAT by observing hemoglobin gradients and microvasculature density in cross-sectional (2D) views. We report on the use of spiral volumetric optoacoustic tomography (SVOT) for an improved characterization of BAT. Procedures: A Streptozotocin-induced diabetes model and control mice were scanned with SVOT. Volumetric oxygen saturation (sO2) as well as total blood volume (TBV) in the subcutaneous interscapular BAT (iBAT) were quantified. Segmentation further enabled separating feeding and draining vessels from the BAT anatomical structure. Results: Scanning revealed a 46% decrease in TBV and a 25% decrease in sO2 in the diabetic iBAT with respect to the healthy control. Conclusions: These results suggest that SVOT may serve as an effective tool for studying the effects of diabetes on BAT. The volumetric optoacoustic imaging probe used for the SVOT scans can be operated in a handheld mode, thus potentially providing a clinical translation route for BAT related studies with this imaging technology.

Flash Scanning Volumetric Optoacoustic Tomography for High Resolution Whole‐Body Tracking of Nanoagent Kinetics and Biodistribution

“…The true volumetric nature of fSVOT has the potential to further refine quantitative readings as compared to the commonly employed cross‐sectional OA imaging approaches. [ 38 ] Note that continuous exposure of AuNP to nanosecond pulsed laser illumination has been reported to lead to significant OA signal degradation, [ 39 ] primarily attributed to their poor thermal stability. This may hamper quantification of time‐lapse dynamics and biodistribution.…”

Multifocal structured illumination optoacoustic microscopy

“…Several important aspects and limitations need to be considered when designing an optimal MSIOAM system. Volumetric OA imaging with spherical arrays is known to benefit from their large angular coverage to enable accurate tomographic OA reconstructions 33,34 . Furthermore, in a spherical array geometry, all the individual elements are directed towards the centre of the FOV, thus facilitating higher sensitivity and better OA image quality compared with standard (e.g., linear or planar) array transducers.…”

Self-Gated Respiratory Motion Rejection for Optoacoustic Tomography

“…While motion correction in OAT might not be relevant for images rendered with a single laser pulse, acquisition of multiple frames is still required in many applications, e.g., for rendering volumetric data from multiple cross-sections or for extending the effective field of view (FOV) of a given imaging system [17]. Multiple frames are also required for multi-spectral optoacoustic tomography (MSOT) applications, where mapping of intrinsic tissue chromophores or extrinsically administered agents is achieved via spectral or temporal unmixing [18][19][20][21]. Cardiac and breathing motion could readily be captured by OAT systems running at frame rates of tens of hertz [22,23], and several approaches have been suggested to mitigate motion artefacts in applications involving multi-frame data analysis.…”