Qubit-Based Simulation of Magnetic Resonance Pulse Sequences

Simulation of medically-relevant magnetic resonance (MR) signals as a function of data acquisition parameters is crucial to the development and optimization of MR spectroscopic and imaging techniques. However, a challenge in MR signal simulation is that systems must often be greatly simplified to perform computational modeling. Quantum computers may offer the ability to simulate more complex MR physics and signals that may not be feasible with classical computing. In this proof-of-concept study, we investigate the use of the qubit Bloch Sphere as a representation of bulk magnetization in MR using simulated and physical qubits. We compared qubit simulation of steady-state free precession (SSFP) signals to classical computation for medically-relevant T₁/T₂ proportions as a function of flip angle and repetition time. Simulations were performed using Cleveland Clinic's IBM Quantum System One and simulated quantum backends with user-selected T₁/T₂ values comparable to the T₁/T₂ of organic material in musculoskeletal anatomy. The similarities between MR imaging and quantum computation pulse sequence operations allow for a new method of studying MR physics and analyzing pulse sequence operations in MR imaging, which takes quantum phenomena into account. This proof-of-concept study demonstrates the feasibility of using qubits for simulation of MR signals and may be extendable to more complex processes such as magnetization transfer or chemical reactions in future work.