Synthetic aperture ultrasound imaging with a ring transducer array: preliminary ex vivo results.
OBJECTIVE
The conventional medical ultrasound imaging has a low lateral spatial resolution, and the image quality depends on the depth of the imaging location. To overcome these problems, this study presents a synthetic aperture (SA) ultrasound imaging method using a ring transducer array.


METHODS
An experimental ring transducer array imaging system was constructed. The array was composed of 2048 transducer elements, and had a diameter of 200 mm and an inter-element pitch of 0.325 mm. The imaging object was placed in the center of the ring transducer array, which was immersed in water. SA ultrasound imaging was then employed to scan the object and reconstruct the reflection image.


RESULTS
Both wire phantom and ex vivo experiments were conducted. The proposed method was found to be capable of producing isotropic high-resolution images of the wire phantom. In addition, preliminary ex vivo experiments using porcine organs demonstrated the ability of the method to reconstruct high-quality images without any depth dependence.


CONCLUSIONS
The proposed ring transducer array and SA ultrasound imaging method were shown to be capable of producing isotropic high-resolution images whose quality was independent of depth.
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.
Xiaolei
X
Qu
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan. azuma@fel.t.u-tokyo.ac.jp.
Takashi
T
Azuma
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.
Takeshi
T
Yogi
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.
Shiho
S
Azuma
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.
Hideki
H
Takeuchi
Department of Biomedical Engineering, Tohoku University, Sendai, 980-8579, Japan.
Satoshi
S
Tamano
Graduate School of Engineering, The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.
Shu
S
Takagi
D000818:Animals; D004867:Equipment Design; D006321:Heart / Q000000981:diagnostic imaging; D007668:Kidney / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D013552:Swine; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods*; D014867:Water
D014867:Water
Ring transducer; Synthetic aperture technique; Ultrasound computed tomography; Ultrasound reflection image