Acquisition-weighted MRSI for Detection and Quantification of BNCT 10B-carrier L-p-boronophenylalanine-fructose Complex, a Phantom Study

Proton magnetic resonance spectroscopy (¹H MRS) is a potential method to detect and quantify a boron neutron capture therapy ¹⁰B-carrier compound, L-p-boronophenylalanine (BPA), in the brain. However, optimal positioning of MRS voxel to capture tissue with maximal BPA concentration can be challenging. Three dimensional proton magnetic resonance spectroscopic imaging (3D ¹H MRSI) provides spectral data covering a large spatial volume, which is a major advantage in detecting and quantifying BPA. BPA detection limit in phantom conditions was determined at 1.5 T using a 3D ¹H MRSI protocol with clinically acceptable nominal spatial resolution and duration. Quantification tests for aqueous phantom were performed using both single voxel MRS and 3D MRSI. In 3D MRSI, BPA detection limit was ~1.0 mM and BPA quantification accuracy was better than ±5%. The results suggest that MRSI would be a feasible method for in vivo BPA evaluation in clinical conditions.