Acoustic Simulation for Transcranial Focused Ultrasound Using GAN-Based Synthetic CT

• Published in: IEEE journal of biomedical and health informatics Vol. 26; no. 1; pp. 161 - 171
• Main Authors: Koh, Heekyung, Park, Tae Young, Chung, Yong An, Lee, Jong-Hwan, Kim, Hyungmin
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.01.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustic resonance; Acoustic simulation; Acoustics; Computed tomography; Computer Simulation; conditional GAN; Density ratio; generative adversarial network; Generative adversarial networks; Generators; Humans; Image quality; Ionizing radiation; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Mental disorders; MRI-only; Neurological diseases; Pressure ratio; Quality assessment; Simulation; single-element transducer; Skull; Skull - diagnostic imaging; Sound transmission; synthetic CT; Tomography, X-Ray Computed - methods; Transcranial focused ultrasound; Transducers; Ultrasonic imaging; Ultrasound; Wave propagation
• ISSN: 2168-2194; 2168-2208; 2168-2208
• DOI: 10.1109/JBHI.2021.3103387

Transcranial focused ultrasound (tFUS) is a promising non-invasive technique for treating neurological and psychiatric disorders. One of the challenges for tFUS is the disruption of wave propagation through the skull. Consequently, despite the risks associated with exposure to ionizing radiation, computed tomography (CT) is required to estimate the acoustic transmission through the skull. This study aims to generate synthetic CT (sCT) from T1-weighted magnetic resonance imaging (MRI) and investigate its applicability to tFUS acoustic simulation. We trained a 3D conditional generative adversarial network (3D-cGAN) with 15 subjects. We then assessed image quality with 15 test subjects: mean absolute error (MAE) = 85.72±9.50 HU (head) and 280.25±24.02 HU (skull), dice coefficient similarity (DSC) = 0.88±0.02 (skull). In terms of skull density ratio (SDR) and skull thickness (ST), no significant difference was found between sCT and real CT (rCT). When the acoustic simulation results of rCT and sCT were compared, the intracranial peak acoustic pressure ratio was found to be less than 4%, and the distance between focal points less than 1 mm.