Virtual Bessel-beam photoacoustic microscopy with extended depth of field using k-Wave

Abstract

Photoacoustic imaging technology is a new imaging technology has emerged in recent years, which combines the advantages of optical imaging and acoustic imaging, optical imaging and acoustic imaging have their own advantages, optical imaging has rich contrast , acoustic imaging has high resolution and high penetration. Photoacoustic imaging has been widely used in biomedical fields, such as brain imaging, tumor detection. As an important branch of photoacoustic imaging technology, optical-resolution photoacoustic microscopy can be applied from cells to tissues. However, the traditional optical-resolution photoacoustic microscopy usually uses a tight focused gaussian beam, the depth-of-field is small, and it is difficult to achieve rapid large volumetric imaging. In order to overcome this issue, researchers have proposed many solutions, one of which is to replace gaussian beams with non-diffracted beams. Bessel beam, as a nondiffracted beam, has a large depth of field. We applied it to optical -resolution photoacoustic microscopy. In reality, the cost of building such a Bessel-beam photoacoustic microscopy is relatively high and the system is complicated. Therefore, a virtual simulation technology is urgently needed for simulation research. Here, we proposed a virtual simulation platform of Bessel-beam photoacoustic microscopy based on k-Wave. The platform generates Bessel beam in the focus area of the objective lens by the circular slit, and the Bessel beam irradiates on the sample to generate the initial photoacoustic pressure field in a wide depth range. The k-Wave is used to simulate the propagation of photoacoustic fields, record photoacoustic signals and image reconstruction. The three-dimensional imaging of vascular network further verifies the large depth of field of Bessel-beam photoacoustic microscopy simulation platform. The establishment of the simulation platform is of great significance to the theoretical research of Bessel-beam photoacoustic microscopy and its application in biomedicine.