In Ultrasound-guided High Intensity Focused Ultrasound (USgHIFU) surgery, the verification of the acoustic coupling correctness between the HIFU transducer and the patient’s body is afundamental stepfor an efficient and safe therapy. Nowadays, cliniciansperformthis checkby qualitative inspectingUltrasoundimages. The aim of this study is the introduction ofanobjectiveindex toquantitively evaluate the couplingon the base ofthe radiofrequency echo signalsacquired during a low-energy HIFU shot. The experimental session involved atissue mimicking phantomandaroboticsystem composed by a HIFU therapeutic transducer and a 2D confocal Ultrasound probe.15 different coupling conditions between the phantom and the transducerwere tested:in each of them, the maximum absolute value of theFourier Transform of theecho signals was computedand employed to determine an Acoustic Coupling (AC) coefficient.Thismetricsshowedasigmoidal trend between ACcoefficient and couplingincrease. This curve can be employed as acalibration tool to quantitatively assess the correctness of the therapeutic set-up before starting the HIFU treatment.
A Pilot Study for a Quantitative Evaluation of Acoustic Coupling in US-guided Focused Ultrasound Surgery
Morchi, L.;Mariani, A.;Cafarelli, A.;Diodato, A.;Tognarelli, S.;Menciassi, A.
2019-01-01
Abstract
In Ultrasound-guided High Intensity Focused Ultrasound (USgHIFU) surgery, the verification of the acoustic coupling correctness between the HIFU transducer and the patient’s body is afundamental stepfor an efficient and safe therapy. Nowadays, cliniciansperformthis checkby qualitative inspectingUltrasoundimages. The aim of this study is the introduction ofanobjectiveindex toquantitively evaluate the couplingon the base ofthe radiofrequency echo signalsacquired during a low-energy HIFU shot. The experimental session involved atissue mimicking phantomandaroboticsystem composed by a HIFU therapeutic transducer and a 2D confocal Ultrasound probe.15 different coupling conditions between the phantom and the transducerwere tested:in each of them, the maximum absolute value of theFourier Transform of theecho signals was computedand employed to determine an Acoustic Coupling (AC) coefficient.Thismetricsshowedasigmoidal trend between ACcoefficient and couplingincrease. This curve can be employed as acalibration tool to quantitatively assess the correctness of the therapeutic set-up before starting the HIFU treatment.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
