Cortical Hemodynamic Responses Under Focused Ultrasound Stimulation Using Real-Time Laser Speckle Contrast Imaging
Yi Yuan, Yanchao Zhao, Hongshuai Jia, Mengyang Liu, Shuo Hu, Yingwei Li, Xiaoli Li
Frontiers in Neuroscience 2018 · 10.3389/fnins.2018.00269
Abstract
Although there is increasing use of focused ultrasound stimulation (FUS) in brain studies, the real-time changes of the cerebral blood flow (CBF) due to FUS remain unclear. In this study, we developed a novel scheme combining FUS and laser speckle contrast imaging, which can be used to measure the CBF caused by FUS in real time. The results showed that the change of CBF increased from 0 to 30 s and reached up to the maximum of 115.1 ± 6.5% at 30 s and then decreased gradually from 30 to 60 s. This study demonstrates that FUS was able to increase CBF and alter cortical hemodynamic responses, which indicates that FUS is a potential non-invasive method to study ischemic stroke rehabilitation.
Abstract via europepmc.
Exposures
Exposure 1: FUS to rat cortex through craniotomy with simultaneous laser speckle imaging
Target: cerebral cortex — “the position of ultrasound stimulation, the anteroposterior (AP:3.5 mm, ML: 2.5 mm)”
Device: other named manufacturer · Siansonic Technology Co., Ltd. · QN8-30C/8-3 customized hollow transducer ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 2,900 | ✓✓✓ |
| Pulse duration (ms) | 0.5 | ✓✓✓⚑ |
| Pulse repetition frequency (Hz) | 1,000 | ✓✓✓ |
| Duty cycle (%) | not reportedpulse duration × PRF gives 50% | |
| Sonication duration (s) | 0.3 | ✓✓✓⚑ |
| Free-field pressure (kPa) | 510 | ✓✓✓ |
|---|---|---|
| Free-field Isppa (W/cm²) | 8.93 | ✓✓✓ |
| Free-field Ispta (W/cm²) | 4.47 | ✓✓✓ |
| In-situ estimate | not reported | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | |
| In-situ Ispta (W/cm²) | not reported |
PRF 1 kHz, 300 tone bursts (NTB), 1450 cycles per pulse, ultrasound duration 300 ms, inter-stimulus interval 1 s; imaging 110 s (baseline 10 s, FUS 10 s, after FUS 90 s).
Flags from extraction
exposures[0].timing.sonication_duration_s— Text gives ultrasound duration 300 ms (NTB 300 at 1 kHz) but also FUS 10 s / SD 10 s in the timeline and Discussion; recorded 0.3 s.n_subjects— 30 rats total (15 experimental, 15 control); recorded the 15 exposed.exposures[0].unspecified_domain.pressure_kpa— 0.51 MPa measured by hydrophone at the focal spot; medium (water or tissue) not stated.exposures[0].timing.pulse_duration_ms— Pulse duration not stated; 1450 cycles per pulse at 2.9 MHz given instead.exposures[0].device.family— Transducer credited to Siansonic as customized hollow transducer; mapped to other_manufacturer.exposures[0].target— Cortical target given only as AP 3.5 mm, ML 2.5 mm craniotomy coordinates.