The study introduces a software pipeline that integrates optical tracking data with acoustic simulations to improve the accuracy of transcranial focused ultrasound (tFUS) procedures. The pipeline was tested on a neuronavigated phantom with and without an ex vivo skull cap. The results showed that the pipeline could replicate the tFUS procedure geometry with a transcranial target registration error (TRE) of 3.9 ± 0.7 mm. The Euclidean distance errors between the simulated focus and the free-field focus predicted by optical tracking were low, at 0.5±0.1 mm for the phantom and 1.2±0.4 mm for the skull cap, indicating the pipeline’s effectiveness in capturing skull-specific effects.

However, the TRE for the simulation informed by optical tracking was 4.6±0.2 mm, which is comparable to or larger than the focal spot size of many tFUS systems. By adjusting the transducer position using the original TRE offset, the simulated TRE was significantly reduced to 1.1 ± 0.4 mm.

Importance: This study is significant as it presents a novel method for enhancing the precision of tFUS procedures, which is crucial for their safety and efficacy. The software pipeline aids in estimating acoustic exposure and the findings emphasize the necessity for image feedback to refine tFUS dosimetry.

Contribution to Literature: The research contributes to the current literature by providing a practical solution to incorporate subject-specific skull information into tFUS procedures, which has been a limitation of optical tracking methods. It also demonstrates the potential of MR-acoustic radiation force imaging to further improve dosimetry accuracy.