Revision 1

Accepted · first revision · record

Title: Transcranial focusing without a prior CT scan
Plain: The skull bends and absorbs sound unevenly, smearing the focus inside the head. Correcting for it currently needs an x-ray scan of the skull.
Precise: Achieve transcranial focal placement accurate to 1 mm and pressure prediction accurate to 10 percent at 0.2 to 1 MHz without computed tomography of the skull, by inferring the skull acoustic properties (sound speed $2.4\,\mathrm{x}\,10^{5} \text{ to } 3.0\,\mathrm{x}\,10^{5}\,\mathrm{cm}/\mathrm{s}$, density, absorption, shear conversion) from ultrasound or magnetic resonance data. An answer is a method with verified focal position and amplitude in human skulls.
Settled by: Hydrophone measurement inside ex vivo human skulls, and in vivo displacement or thermometry confirmation, against the predicted focus.
Kind: well-posed
Answer type: value
References: (empty)
Literature status: open
Status note: (empty)
Posed since: 2000