Photoacoustic clutter reduction by inversion of a linear scatter model using plane wave ultrasound measurements

Abstract

Abstract:Photoacoustic imaging aims to visualize light absorption properties of biological tissue by receiving a sound wave that is generated inside the observed object as a result of the photoacoustic effect. In clinical applications, the strong light absorption in human skin is a major problem. When high amplitude photoacoustic waves that originate from skin absorption propagate into the tissue, they are reflected back by acoustical scatterers and the reflections contribute to the received signal. The artifacts associated with these reflected waves are referred to as clutter or skin echo and limit the applicability of photoacoustic imaging for medical applications severely. This study seeks to exploit the acoustic tissue information gained by plane wave ultrasound measurements with a linear array in order to correct for reflections in the photoacoustic image. By deriving a theory for clutter waves in k-space and a matching inversion approach, photoacoustic measurements compensated for clutter are shown to be recovered.

Reflection artifact identification in photoacoustic imaging using multi-wavelength excitation

“…Several methods for reducing RAs have been presented [14][15][16][17][18]. Deformation Compensated Averaging (DCA) [14] employs tissue deformation for de-correlating the artifact by slightly palpating the tissue.…”

“…Recently, LOVIT has been further improved by using multiple foci [19]. Another method exploits the acoustic tissue information by inversion of a linear scatter model using plane wave US measurements [16]. This method has to match PA and US measurements and requires numerous plane wave angles limiting itself to real-time performance.…”

Feasibility of photoacoustic/ultrasound imaging of synovitis in finger joints using a point-of-care system

“…Previous studies showed that linear array-based systems such as used in this study are susceptible to clutter and reflection artefacts [45] . Future studies should therefore include clutter reduction and artefact removal [46] , [47] . We were able to reject the possibility of most types of artefacts by moving the illumination position in relation to the finger – for most types of artefacts the appearance of PA features would move in relation to the US image [48] , but this did not happen in the cases investigated here.…”

Identification and elimination of reflection artifacts in biomedical photoacoustic imaging

“…Several groups have reported on fast algorithms based on frequency domain processing [26,27]. Systems have been presented that can do real time reconstruction of PA images [28][29][30], and some others based on recent developments in GPU technology which can do real-time PA and US imaging [14].…”

“…Several methods have been studied for identifying and reducing reflection artifacts in PA imaging [24,26,28,29]. LOVIT [24] and DCA [26] aim at reducing reflection artifacts that occur below a certain depth (typically below 15 mm).…”