Noninvasive photoacoustic detecting intraocular foreign bodies with an annular transducer array

Abstract

We present a fast photoacoustic imaging system based on an annular transducer array for detection of intraocular foreign bodies. An eight-channel data acquisition system is applied to capture the photoacoustic signals using multiplexing and the total time of data acquisition and transferring is within 3 s. A limited-view filtered back projection algorithm is used to reconstruct the photoacoustic images. Experimental models of intraocular metal and glass foreign bodies were constructed on ex vivo pig's eyes and clear photoacoustic images of intraocular foreign bodies were obtained. Experimental results demonstrate the photoacoustic imaging system holds the potential for in clinic detecting the intraocular foreign bodies.

Low-cost photoacoustic imaging systems based on laser diode and light-emitting diode excitation

“…65 Currently, pulsed laser diodes are commercially available with a hundreds-watt-level power output at near-infrared (NIR) wavelengths, and continuous-wave (CW) LEDs can cover the full visible (VIS) spectrum. [66][67][68][69][70][71][72][73][74][75][76][77] They could play a broad role in super¯cial vascular PAI, especially where the laser energy requirements are relatively modest. Although the relatively weak power represents a main disadvantage for e±cient photoacoustic e®ect, there is still substantial scope to mitigate this for deeper imaging depth by time and frequency methods.…”

An examination of polyvinylidene fluoride capacitive sensors as ultrasound transducer for imaging applications

“…Photoacoustic tomography (PAT) is a fast growing research subject that has attracted wide interest after the prospect of providing high-quality tomography images [1][2][3][4][5][6]. PAT is based on measuring mechanical disturbances at ultrasonic bandwidths resulting from the optical absorption of laser short pulses that excite the tissue of interest.…”

Photoacoustic Imaging of Animals with an Annular Transducer Array

“…The individual element of the array features an elevation height of 8 mm, an elementary pitch of 1.1 mm and an element inter space of 0.04 mm, and the relative pulse-echo sensitivity is −29 dB. The lateral resolution of the imaging system is about 0.1 mm at the center of the transducer array [11] and the radial resolution is a nearly constant value of 0.08 mm throughout the imaging area. The bottom of the annular array was sealed with an elastic transparent membrane and the side face was sealed up with polyethylene materials to form a water tank.…”