Ultrasound system for precise neuromodulation of human deep brain circuits

The data was collected for characterisation and validation of focusing, steering and aberration correction of a 256 element pseudorandom hemi ellipsoidal array transducer operating at 555 kHz. Measurements were made both in free field and after propagation through ex vivo human skulls.
Measurements were made with a custom Fabry-Perot fibre optic hydrophone in a custom water tank with automated scanning axes. The system was driven with an 80 cycle pulse with 8 V drive voltage amplitude in free field. Measurements made with skulls used drive voltages required to obtain a focal pressure of 775 kPa after propagation through each skull.
The study data contains 10 standard format measurement data files and an additional two files containing corresponding simulation data.

UCL-k-Stim-Validation-01 – line scans at [0, 0, 0], [60, 0, 0] mm – 27/06/23
UCL-k-Stim-Validation-02 – line scans at [0, 0, 50] mm, [0, 50, 0] mm, [30, 30, 30] mm – 28/06/23
UCL-k-Stim-Validation-03 – line scans at [0, -50, 0] mm, [-60, 0, 0] mm – 30/06/23
UCL-k-Stim-Validation-04 – line scans at [0, 0, 20] mm, [0, 0, -20] mm, [0, 0, -50] mm, [0, 20, 0] mm, [0, -20, 0] mm, [20, 0, 0] mm, [20, 20, 0] mm, [20, 20, 20] mm, [20, 20, -20] mm, [30, 30, -30] mm, [-20, 0, 0] mm.
Scans with ex vivo human skulls, testing planning pipeline – inverse planning with aberration correction perfomed using k-Plan to obtain drive amplitudes and phases for a target focal pressure of 775 kPa:
UCL-k-Stil-Validation-05 – line scans at [0, 0, 0] mm, [20, 0, 0] mm, [0, 20, 10] mm, [0, 0, 20] mm with skull A 2157 mounted within the helmet.
UCL-k-Stim-Validation-06 – line scans at [0, 0, 0] mm, [20, 0, 0] mm, [0, 20, 0] mm, [0, 0, 20] mm with skull B 2120 mounted within the helmet.
UCL-k-Stim-Validation-07 – line scans at [0, 0, 0] mm, [20, 0, 0] mm, [0, 20, 0] mm, [0, 0, 20] mm with skull C 2147 mounted within the helmet.
UCL-k-Stim-Validation-08 – line scans at [0, 0, 0] mm, [20, 0, 0] mm, [0, 20, 0] mm, [0, 0, 20] mm, with skull D 2117 mounted within the helmet.
Scans with an ex vivo human skull, testing the online replanning pipeline – inverse planning with aberration correction performed in k-Plan with an additional geometrical phase shift to move the focal position, target pressure of 775 kPa:
UCL-k-Stim-Validation-09 – line scans at [0, 0, 0] mm, [0, 20, 0] mm with planned phases only, then with geometric phase shift from [0, 0, 0] mm to [5, 0, 0] mm, [-5, 0, 0] mm, [0, 5, 0] mm, [0, -5, 0] mm, with skull C 2147 mounted in the helmet.
UCL-k-Stim-Validation-10 – line scans at with k-Plan focus at [0, 0, 0] mm with geometric phase shift from [0, 0, 0] mm to [0, 0, 5] mm, [0, 0, -5] mm, and from [0, 20, 0] mm to [5, 20, 0] mm, [0, 25, 0] mm, [2, 18, -2] mm, with skull C 2147 mounted in the helmet.
Additional files:
free_field_sims_water_steering_props.mat contains simulated free field focal parameters including spatial peak pressure, dimensions of the focal region, and line profiles through the focus for 16 focal positions. Simulations were run using the acousticFieldPropagator function in k-Wave.
skull_plan_metrics.mat contains simulated transcranial focal parameters for 4 focal positions within each of 4 skulls, including profiles through the focus, location of the spatial peak pressure, focal dimensions, and the difference between these parameters and the measurements. Simulations were run with aberration correction in k-Plan using CT scans of the skulls.

本数据集采集自一款工作于555 kHz的256元伪随机半球椭球阵列换能器，用于对其聚焦、波束偏转及像差校正性能进行表征与验证。实验分别在自由声场以及穿过离体人类颅骨后的传播环境中开展。

本次测量采用定制法布里-珀罗（Fabry-Perot）光纤水听器，在带有自动扫描轴的定制水槽中完成。自由声场实验中，系统由幅值为8 V的80周期脉冲驱动；颅骨穿透实验中，则采用经每块颅骨传播后可获得775 kPa焦点声压所需的驱动电压。

本研究数据集包含10个标准格式的测量数据文件，以及2个配套的仿真数据文件。

UCL-k-Stim-Validation-01 —— 针对[0, 0, 0]、[60, 0, 0] mm位置的线扫描 —— 27/06/23
UCL-k-Stim-Validation-02 —— 针对[0, 0, 50] mm、[0, 50, 0] mm、[30, 30, 30] mm位置的线扫描 —— 28/06/23
UCL-k-Stim-Validation-03 —— 针对[0, -50, 0] mm、[-60, 0, 0] mm位置的线扫描 —— 30/06/23
UCL-k-Stim-Validation-04 —— 针对[0, 0, 20] mm、[0, 0, -20] mm、[0, 0, -50] mm、[0, 20, 0] mm、[0, -20, 0] mm、[20, 0, 0] mm、[20, 20, 0] mm、[20, 20, 20] mm、[20, 20, -20] mm、[30, 30, -30] mm、[-20, 0, 0] mm位置的线扫描。

采用离体人类颅骨开展的扫描实验，用于测试规划管线——通过k-Plan执行带像差校正的逆规划，以获取目标焦点声压为775 kPa的驱动幅值与相位：
UCL-k-Stil-Validation-05 —— 于头盔内安装颅骨A 2157时，针对[0, 0, 0] mm、[20, 0, 0] mm、[0, 20, 10] mm、[0, 0, 20] mm位置开展的线扫描。
UCL-k-Stim-Validation-06 —— 于头盔内安装颅骨B 2120时，针对[0, 0, 0] mm、[20, 0, 0] mm、[0, 20, 0] mm、[0, 0, 20] mm位置开展的线扫描。
UCL-k-Stim-Validation-07 —— 于头盔内安装颅骨C 2147时，针对[0, 0, 0] mm、[20, 0, 0] mm、[0, 20, 0] mm、[0, 0, 20] mm位置开展的线扫描。
UCL-k-Stim-Validation-08 —— 于头盔内安装颅骨D 2117时，针对[0, 0, 0] mm、[20, 0, 0] mm、[0, 20, 0] mm、[0, 0, 20] mm位置开展的线扫描。

采用单块离体人类颅骨开展的扫描实验，用于测试在线重新规划管线——通过k-Plan执行带像差校正的逆规划，并附加几何相移以移动焦点位置，目标声压为775 kPa：
UCL-k-Stim-Validation-09 —— 于头盔内安装颅骨C 2147时，先仅采用规划相位在[0, 0, 0] mm、[0, 20, 0] mm位置开展线扫描，随后附加几何相移，将焦点从[0, 0, 0] mm移动至[5, 0, 0] mm、[-5, 0, 0] mm、[0, 5, 0] mm、[0, -5, 0] mm位置并开展线扫描。
UCL-k-Stim-Validation-10 —— 于头盔内安装颅骨C 2147时，针对k-Plan规划的[0, 0, 0] mm焦点位置附加几何相移，将焦点移动至[0, 0, 5] mm、[0, 0, -5] mm，以及从[0, 20, 0] mm移动至[5, 20, 0] mm、[0, 25, 0] mm、[2, 18, -2] mm位置开展的线扫描。

附加文件：
free_field_sims_water_steering_props.mat 包含16个焦点位置的仿真自由声场焦点参数，涵盖空间峰值声压、焦点区域尺寸以及焦点处的线分布轮廓。仿真通过k-Wave中的acousticFieldPropagator函数运行。
skull_plan_metrics.mat 包含4块颅骨各4个焦点位置的仿真经颅焦点参数，涵盖焦点处的分布轮廓、空间峰值声压位置、焦点尺寸，以及上述参数与实测值之间的差值。仿真通过k-Plan结合颅骨CT扫描数据执行像差校正后完成。