G T Clement and K Hynynen 2002 Phys. Med. Biol. 47 1219 doi:10.1088/0031-9155/47/8/301
G T Clement and K Hynynen
Show affiliationsA technique for focusing ultrasound through the human skull is described and verified. The approach is based on a layered wavevector-frequency domain model, which propagates ultrasound from a hemisphere-shaped transducer through the skull using input from CT scans of the head. The algorithm calculates the driving phase of each transducer element in order to maximize the signal at the intended focus. This approach is tested on ten ex vivo human skulls using a 0.74 MHz, 320-element array. A stereotaxic reference frame is affixed to the skulls in order to provide accurate registration between the CT images and the transducer. The focal quality is assessed with a hydrophone placed inside the skull. In each trial the phase correction algorithm successfully restored the focus inside the skull at a location within 1 mm from the intended focal point. The results demonstrate the feasibility of using the method for completely non-invasive ultrasound brain surgery and therapy.
Issue 8 (21 April 2002)
Received 7 January 2002
Published 5 April 2002
G T Clement and K Hynynen 2002 Phys. Med. Biol. 47 1219
Chang Su Kim et al 2006 Semicond. Sci. Technol. 21 1022
S R Hudson et al 2004 Plasma Phys. Control. Fusion 46 869
F M Reicha et al 1991 J. Phys. D: Appl. Phys. 24 369
Kihyung Lee and Rolf D Reitz 2004 Meas. Sci. Technol. 15 509
Peter E Andersen et al 2004 Phys. Med. Biol. 49 1307
Petr Plechác and Vladimír Sverák 2003 Nonlinearity 16 2083
U Mizutani et al 1990 J. Phys.: Condens. Matter 2 6169
S S Manna 1991 J. Phys. A: Math. Gen. 24 L363
JaeTae Seo et al 2006 J. Phys.: Conf. Ser. 38 53