A Simulation of the Effects of Diffusion on Hyperpolarized [1-C]-Pyruvate Signal Evolution.

Objective: Hyperpolarized [1-C]-pyruvate magnetic resonance imaging is an emerging metabolic imaging method that offers unprecedented spatiotemporal resolution for monitoring tumor metabolism in vivo. To establish robust imaging biomarkers of metabolism, we must characterize phenomena that may modulate the apparent pyruvate-to-lactate conversion rate (k). Here, we investigate the potential effect of diffusion on pyruvate-to-lactate conversion, as failure to account for diffusion in pharmacokinetic analysis may obscure true intracellular chemical conversion rates.

Model-constrained reconstruction accelerated with Fourier-based undersampling for hyperpolarized [1- C] pyruvate imaging.

Purpose: Model-constrained reconstruction with Fourier-based undersampling (MoReFUn) is introduced to accelerate the acquisition of dynamic MRI using hyperpolarized [1- C]-pyruvate.

Methods: The MoReFUn method resolves spatial aliasing using constraints introduced by a pharmacokinetic model that describes the signal evolution of both pyruvate and lactate. Acceleration was evaluated on three single-channel data sets: a numerical digital phantom that is used to validate the accuracy of reconstruction and model parameter restoration under various SNR and undersampling ratios, prospectively and retrospectively sampled data of an in vitro dynamic multispectral phantom, and retrospectively undersampled imaging data from a prostate cancer patient to test the fidelity of reconstructed metabolite time series.

Projection-based stereolithography for direct 3D printing of heterogeneous ultrasound phantoms.

Modern ultrasound (US) imaging is increasing its clinical impact, particularly with the introduction of US-based quantitative imaging biomarkers. Continued development and validation of such novel imaging approaches requires imaging phantoms that recapitulate the underlying anatomy and pathology of interest. However, current US phantom designs are generally too simplistic to emulate the structure and variability of the human body.

Development of a rational strategy for integration of lactate dehydrogenase A suppression into therapeutic algorithms for head and neck cancer.

Background: Lactate dehydrogenase (LDH) is a critical metabolic enzyme. LDH A (LDHA) overexpression is a hallmark of aggressive malignancies and has been linked to tumour initiation, reprogramming and progression in multiple tumour types. However, successful LDHA inhibition strategies have not materialised in the translational and clinical space.