Transcranial functional ultrasound imaging shows widespread hemodynamic changes induced by focused ultrasound (FUS)
Jonas Bendig, Christian Aurup, Samuel G. Blackman, Erica P. McCune, Seongyeon Kim, Elisa E. Konofagou
Scientific Reports 2026 · 10.1038/s41598-026-62583-3
Exposures
Exposure 1: Transcranial FUS, 1.68 MHz (H-204)
Target: primary somatosensory cortex, hippocampus, thalamus — “transcranial/cranial-window sonication along midline or ±1 mm ML; sonicated structures (somatosensory cortex, hippocampus, thalamus) depended on the AP imaging plane”
Device: Sonic Concepts · Sonic Concepts Inc, Bothell, WA, USA (transducer); Vermon S.A., Tours, France (imaging array); Verasonics Inc. (Vantage 256 system) · H-204 / H-215 single-element annular transducer with L22-14vXLF imaging array ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,680 | ✓✓✓ |
| Pulse duration (ms) | 150 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 1 | ✓✓✓ |
| Duty cycle (%) | 64pulse duration × PRF gives 15%, which disagrees with the stated value | ✓✓✓⚑ |
| Sonication duration (s) | 20 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | deratingmean or range across subjects | |
| In-situ pressure (kPa) | 800, 2,600swept | ✓✓✓ |
| In-situ Isppa (W/cm²) | not reported | ⚑ |
| In-situ Ispta (W/cm²) | 1.9, 20.06swept | ✓✓✓ |
A block design was implemented consisting of a 60 s baseline imaging block followed by four 20 s FUS blocks with intervals randomized between 60 and 90 s. Each 20-s FUS block consisted of a 150-ms burst delivered at ~1 Hz (H-204) or ~2 Hz (H-215) ("sonication frequency"), amplitude-modulated by a 1-kHz half-sine envelope corresponding to an energy-equivalent duty cycle of 64%; this nested burst/AM structure does not reduce to a single PRF-duty-cycle pair.
Exposure 2: Cranial-window FUS, 1.68 MHz (H-204, non-derated)
Target: primary somatosensory cortex, hippocampus, thalamus — “transcranial/cranial-window sonication along midline or ±1 mm ML; sonicated structures (somatosensory cortex, hippocampus, thalamus) depended on the AP imaging plane”
Device: Sonic Concepts · Sonic Concepts Inc, Bothell, WA, USA (transducer); Vermon S.A., Tours, France (imaging array); Verasonics Inc. (Vantage 256 system) · H-204 / H-215 single-element annular transducer with L22-14vXLF imaging array ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,680 | ✓✓✓ |
| Pulse duration (ms) | 150 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 1 | ✓✓✓ |
| Duty cycle (%) | 64pulse duration × PRF gives 15%, which disagrees with the stated value | ✓✓✓ |
| Sonication duration (s) | 20 | ✓✓✓ |
| Free-field pressure (kPa) | 700, 2,800swept | ✓✓✓ |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | 1.45, 23.27swept | ✓✓✓ |
| In-situ estimate | measurementmean or range across subjects | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | ⚑ |
| In-situ Ispta (W/cm²) | not reported |
A block design was implemented consisting of a 60 s baseline imaging block followed by four 20 s FUS blocks with intervals randomized between 60 and 90 s. Each 20-s FUS block consisted of a 150-ms burst delivered at ~1 Hz (H-204) or ~2 Hz (H-215) ("sonication frequency"), amplitude-modulated by a 1-kHz half-sine envelope corresponding to an energy-equivalent duty cycle of 64%; this nested burst/AM structure does not reduce to a single PRF-duty-cycle pair.
Exposure 3: Cranial-window FUS, 4 MHz (H-215, derated brain tissue)
Target: primary somatosensory cortex, hippocampus, thalamus — “transcranial/cranial-window sonication along midline or ±1 mm ML; sonicated structures (somatosensory cortex, hippocampus, thalamus) depended on the AP imaging plane”
Device: Sonic Concepts · Sonic Concepts Inc, Bothell, WA, USA (transducer); Vermon S.A., Tours, France (imaging array); Verasonics Inc. (Vantage 256 system) · H-204 / H-215 single-element annular transducer with L22-14vXLF imaging array ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 4,000 | ✓✓✓ |
| Pulse duration (ms) | 150 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 2 | ✓✓✓ |
| Duty cycle (%) | 64pulse duration × PRF gives 30%, which disagrees with the stated value | ✓✓✓ |
| Sonication duration (s) | 20 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | deratingmean or range across subjects | |
| In-situ pressure (kPa) | 960, 2,230swept | ✓✓✓ |
| In-situ Isppa (W/cm²) | 31.18, 168.2swept | ✓✓✓ |
| In-situ Ispta (W/cm²) | 2.99, 16.15swept | ✓✓✓⚑ |
A block design was implemented consisting of a 60 s baseline imaging block followed by four 20 s FUS blocks with intervals randomized between 60 and 90 s. Each 20-s FUS block consisted of a 150-ms burst delivered at ~1 Hz (H-204) or ~2 Hz (H-215) ("sonication frequency"), amplitude-modulated by a 1-kHz half-sine envelope corresponding to an energy-equivalent duty cycle of 64%; this nested burst/AM structure does not reduce to a single PRF-duty-cycle pair.
Flags from extraction
n_subjects— Paper gives separate mouse counts for transcranial (n=22) and cranial-window (n=5) cohorts; unclear whether the cranial-window subgroup overlaps with the transcranial cohort (different age ranges given), so totals are not summed.exposures[0].in_situ.isppa_w_cm2— The Isppa row in Table 1 is garbled in the source text/table conversion (a numeric range appears with no clear skull/transcranial vs cranial-window label attached); left not_reported rather than guessing the attribution.exposures[1].in_situ.isppa_w_cm2— Same Table 1 formatting/garbling issue as above; the non-derated cranial-window H204 Isppa value could not be unambiguously identified.exposures[2].in_situ.ispta_w_cm2— Table 1 lists the Ispta label for 'Derated: brain tissue, Cranial window, H215' but the corresponding numeric value appears to be missing/garbled in the source table.exposures[0].timing.duty_cycle_pct— The paper states an energy-equivalent duty cycle of 64% arising from a 1-kHz amplitude-modulated sine envelope within each 150-ms burst; this differs conceptually from the classic PRF x pulse-duration duty cycle and does not arithmetically reconcile with the ~1 Hz (H-204) / ~2 Hz (H-215) burst repetition rate mentioned elsewhere -- recorded as stated but flagged as an unusual/nested definition.exposures[0].target.terms— FUS focal position and imaging plane varied across animals (AP -0.2 to -2.0 mm from Bregma); the exact sonicated structure was not fixed and multiple candidate regions (somatosensory cortex, hippocampus, thalamus) are named as possibilities depending on plane.exposures[1].device.family— No single named commercial neuromodulation device family fits; classified as commercial_other reflecting the combination of a Sonic Concepts transducer with a Vermon imaging array driven by a Verasonics research system.