A 63 element 1.75 dimensional ultrasound phased array for the treatment of benign prostatic hyperplasia

Abstract

BackgroundProstate cancer and benign prostatic hyperplasia are very common diseases in older American men, thus having a reliable treatment modality for both diseases is of great importance. The currently used treating options, mainly surgical ones, have numerous complications, which include the many side effects that accompany such procedures, besides the invasive nature of such techniques. Focused ultrasound is a relatively new treating modality that is showing promising results in treating prostate cancer and benign prostatic hyperplasia. Thus this technique is gaining more attention in the past decade as a non-invasive method to treat both diseases.MethodsIn this paper, the design, construction and evaluation of a 1.75 dimensional ultrasound phased array to be used for treating prostate cancer and benign prostatic hyperplasia is presented. With this array, the position of the focus can be controlled by changing the electrical power and phase to the individual elements for electronically focusing and steering in a three dimensional volume. The array was designed with a maximum steering angle of ± 13.5° in the transverse direction and a maximum depth of penetration of 11 cm, which allows the treatment of large prostates. The transducer piezoelectric ceramic, matching layers and cable impedance have been designed for maximum power transfer to tissue.ResultsTo verify the capability of the transducer for focusing and steering, exposimetry was performed and the results correlated well with the calculated field. Ex vivo experiments using bovine tissue were performed with various lesion sizes and indicated the capability of the transducer to ablate tissue using short sonications.ConclusionA 1.75 dimensional array, that overcame the drawbacks associated with one-dimensional arrays, has been designed, built and successfully tested. Design issues, such as cable and ceramic capacitances, were taken into account when designing this array. The final prototype overcame also the problem of generating grating lobes at unwanted locations by tapering the array elements.

Three-axis MR-conditional robot for high-intensity focused ultrasound for treating prostate diseases transrectally

“…The two dominant clinically available systems using transrectal HIFU are Ablatherm HIFU (Technomed International, Lyon, France) and HIFU Sonablate 500 (Focal Surgery, Milpitas, CA now SonaCare Medical, Charlotte, North Carolina). Recent advances of the transrectal device include a phased array probe for more efficient treatment of prostate [ 21 ].…”

Image-guided ultrasound phased arrays are a disruptive technology for non-invasive therapy

“…Linear 1D arrays can steer the beam in the axial plane of the array, and have also been proposed for endocavity applications (Buchanan and Hynynen 1994, Diederich and Burdette 1996, Gavrilov and Hand 1997. For completeness, it is worth noting that 1.25D, 1.5D, and 1.75D arrays (for definitions, see Wildes et al (1997)) have also been proposed for use in therapy arrays (Wildes et al 1997, Curiel et al 2002, Saleh and Smith 2005.…”

Removing atherosclerotic plaque created using high cholesterol diet in rabbit using ultrasound

“…The two dominant clinically available systems using transrectal HIFU are Ablatherm HIFU (Technomed International, Lyon, France) and HIFU Sonablate 500 (Focal Surgery, Milpitas, CA now SonaCare Medical, Charlotte, NC, USA). Recent advances of the transrectal device includes a phased-array probe for more efficient treatment of the prostate [ 23 ]. Another clinical success that employs therapeutic ultrasound with magnetic imaging guidance (MRI) is the technology introduced by the Israeli company InSightec [ 24 ].…”