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arXiv · 2501.00179

Focus Correction in MR thermography for Precise Targeting in Focused Ultrasound Thalamotomy

Chang-Sheng Mei·Shenyan Zong·Bruno Madore·Garth R. Cosgrove·Nathan J. McDannold
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Abstract

Purpose: To adjust the location of the ablation focus by correcting the spatial discrepancy induced by temperature changes between the target coordinate and the hotspot as seen in MR thermography. Methods: A two-step correction procedure was used to account for the chemical and k-space shifts. The first step corrected the spatial shift pixel by pixel using the field map around the focus. The second step calculated the temperature-induced TE variation map to compensate for the center location offset of the focus. Results: The approximately 1mm shift caused by chemical shift and k-space center offset was adjusted using the field map and TE error map. The mean temperature error was reduced to -0.05{\deg}C, as opposed to -0.11{\deg}C obtained using only a chemical shift correction. Conclusion: Correcting for the spatial shifts of hotspots caused by field gradients and k-space shifts in temperature changes can ensure precise targeting in FUS thalamotomy.

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Chang-Sheng Mei, Shenyan Zong, Bruno Madore, Garth R. Cosgrove, Nathan J. McDannold. 2024-12-30. Focus Correction in MR thermography for Precise Targeting in Focused Ultrasound Thalamotomy. https://arxiv.org/abs/2501.00179

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