Modified algebraic reconstruction technique based on circular scanning geometry to improve processing time in photoacoustic tomography

Photoacoustic imaging is low-risk, and noninvasive tool for imaging biological tissues that acoustically respond to absorbed irradiating nonionized short laser pulse by tissue, then the image of light energy absorption distribution in the tissue has been reconstructed by image reconstruction algorithms. Indeed, photoacoustic tomography is a hybrid imaging modality that combines pure optical and acoustic imaging methods to take advantage of them, therefore, it contains high optical contrast with good ultrasonic resolution. However, improving its main parts is challenging. One of the most important parts of photoacoustic imaging is image reconstruction using appropriate algorithms. There are various image reconstruction methods. Image reconstruction based on an algebraic algorithm can reconstruct a clear image without artifact, but the algorithm is typically time-consuming. This paper deals with this drawback of the algorithm. Simulations demonstrate significant improvement in the processing time of reconstructed images achieved by our proposed algorithm as compared to the phase-controlled algorithm. Based on the image reconstruction algorithm in circular scanning geometry presented in this article, the processing time required to create a 2D tomographic image is reduced from 60 to 3.89 s compared to our previous work, which was based on a phase-controlled algorithm. This improvement was based on inspiration from the experiences of our past works in dealing with various image reconstruction algorithms, which ultimately led to improvement in the calculation time.