MRI Distortion Characterization Using Physical and Digital Phantoms

The patent creates a digital twin (virtual copy) of the physical phantom that replicates its magnetic resonance properties. This digital model can be simulated without physical constraints, allowing calibration reference generation that is independent of physical reference equipment imperfections. The digital twin is solved using Bloch equations to generate expected signal values that serve as a reliable calibration reference.

The patent introduces a digital phantom as an intermediary between the physical measurement system and the calibration process. Instead of directly comparing measurements to physical reference standards, the system uses the digital phantom to generate expected signals, which then serve as the reference for comparing against actual MRI measurements, thereby eliminating dependency on physical reference equipment.

The patent extracts only the essential magnetic resonance properties (relaxation times T1 and T2, proton density) from the complex spin trajectory simulation. Instead of tracking individual spin trajectories through the magnetic field, the method directly solves the Bloch equations for these key parameters, obtaining the necessary signal prediction information while eliminating the computationally expensive trajectory tracking component.

The patent changes the simulation approach from tracking spatial trajectories of spins to directly solving for magnetic resonance parameters (T1, T2, proton density) using Bloch equations. This parameter transformation converts a computationally intensive spatial simulation into a more efficient parametric solution that achieves the same calibration objective with reduced computational resources.