High-frequency annular array with coaxial illumination for dual-modality ultrasonic and photoacoustic imaging. Academic Article uri icon

Overview

abstract

  • This paper presents a combined ultrasound and photoacoustic (PA) imaging (PAI) system used to obtain high-quality, co-registered images of mouse-embryo anatomy and vasculature. High-frequency ultrasound (HFU, >20 MHz) is utilized to obtain high-resolution anatomical images of small animals while PAI provides high-contrast images of the vascular network. The imaging system is based on a 40 MHz, 5-element, 6 mm aperture annular-array transducer with a 800 μm diameter hole through its central element. The transducer was integrated in a cage-plate assembly allowing for a collimated laser beam to pass through the hole so that the optical and acoustic beams were collinear. The assembly was mounted on a two-axis, motorized stage to enable the simultaneous acquisition of co-registered HFU and PA volumetric data. Data were collected from all five elements in receive and a synthetic-focusing algorithm was applied in post-processing to beamform the data and increase the spatial resolution and depth-of-field (DOF) of the HFU and PA images. Phantom measurements showed that the system could achieve high-resolution images (down to 90 μm for HFU and 150 μm for PAI) and a large DOF of >8 mm. Volume renderings of a mouse embryo showed that the scanner allowed for visualizing morphologically precise anatomy of the entire embryo along with corresponding co-registered vasculature. Major head vessels, such as the superior sagittal sinus or rostral vein, were clearly identified as well as limb bud vasculature.

publication date

  • May 1, 2013

Research

keywords

  • Photoacoustic Techniques
  • Ultrasonics

Identity

PubMed Central ID

  • PMC3676372

Scopus Document Identifier

  • 84878940157

Digital Object Identifier (DOI)

  • 10.1016/j.ultrasmedbio.2010.02.006

PubMed ID

  • 23742556

Additional Document Info

volume

  • 84

issue

  • 5