Characterization of lens based photoacoustic imaging system

Francis, Kalloor Joseph; Chinni, Bhargava; Channappayya, Sumohana S.; Rajalakshmi, P.; Dogra, Vikram S.; Rao, Navalgund

doi:10.1016/j.pacs.2017.09.003

Cited by 21 publications

(29 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There are several metrics for evaluating OAI platforms. The first three are the axial, lateral, and elevational resolutions, analogous to ultrasound imaging [ [43] , [44] , [45] ]. These describe the spatial resolution of the platform along the imaging axis (axial), perpendicular to the imaging axis on the image plane (lateral), and between image planes (elevational).…”

Section: Introductionmentioning

confidence: 99%

Hand-held optoacoustic imaging: A review

2018

View full text Add to dashboard Cite

Optoacoustic imaging is a medical imaging modality that uses optical excitation and acoustic detection to generate images of tissue structures based up optical absorption within a tissue sample. This imaging modality has been widely explored as a tool for a number of clinical applications, including cancer diagnosis and wound healing tracking. Recently, the optoacoustic imaging community has published a number of reports of hand-held optoacoustic imaging devices and platforms; these hand-held configurations improve the modality’s potential for commercial clinical implementation. Here, we review recent advancements in hand-held optoacoustic imaging platforms and methods, including recent pre-clinical applications, and we present an overview of the remaining limitations in optoacoustic imaging that must be addressed to increase the translation of the modality into commercial and clinical use.

show abstract

Section: Introductionmentioning

confidence: 99%

Hand-held optoacoustic imaging: A review

2018

View full text Add to dashboard Cite

show abstract

“…Assume a lens with thickness Δ 0 and focal length F . Let 2 F be the distance from the center of the lens, then the phase change introduced by the lens at radius r L from the center can be written as [3],normalΦ(rL)=eik0Δ0e-ik0rL22F,with k 0 = 2 πf 0 / c 0 , where a monochromatic approach is used with f 0 = f c taken as the center frequency of the transducer. c 0 is the speed of sound in the medium.…”

Section: Introductionmentioning

confidence: 99%

“…Acoustic lens based PA imaging is a potential alternative to conventional computational reconstruction based imaging. The lens-based approach eliminates computational and memory intense reconstruction and offers a simple, low-cost and real-time implementation [2] , [3] .…”

Section: Introductionmentioning

confidence: 99%

“…These volumetric imaging methods utilized the movement of the sensor plane to focus and image multiple depths or used a fixed sensor for a small volume around 2F plane [13] , [14] . An extensive theoretical and experimental study of PA camera PSF at different depth planes and off-axis locations was conducted by Francis et al in 2017 [3] . It was shown that the axial resolution of the system is determined by the transducer impulse response while the lateral resolution is mainly determined by the lens parameters and the center frequency of the transducer.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Multiview spatial compounding using lens-based photoacoustic imaging system

et al. 2019

Self Cite

View full text Add to dashboard Cite

Recently, an acoustic lens has been proposed for volumetric focusing as an alternative to conventional reconstruction algorithms in Photoacoustic (PA) Imaging. Acoustic lens can significantly reduce computational complexity and facilitate the implementation of real-time and cost-effective systems. However, due to the fixed focal length of the lens, the Point Spread Function (PSF) of the imaging system varies spatially. Furthermore, the PSF is asymmetric, with the lateral resolution being lower than the axial resolution. For many medical applications, such as in vivo thyroid, breast and small animal imaging, multiple views of the target tissue at varying angles are possible. This can be exploited to reduce the asymmetry and spatial variation of system the PSF with simple spatial compounding. In this article, we present a formulation and experimental evaluation of this technique. PSF improvement in terms of resolution and Signal to Noise Ratio (SNR) with the proposed spatial compounding is evaluated through simulation. Overall image quality improvement is demonstrated with experiments on phantom and ex vivo tissue. When multiple views are not possible, an alternative residual refocusing algorithm is proposed. The performances of these two methods, both separately and in conjunction, are compared and their practical implications are discussed.

show abstract

“…The acoustic lens helps to circumvent the reconstruction works. The tissue specimen was placed at 2f position and PA image acquired at 2f position from the acoustic lens for a unit magnification[32].…”

mentioning

confidence: 99%

Automatic cancer tissue detection using multispectral photoacoustic imaging

et al. 2019

Self Cite

View full text Add to dashboard Cite

Convolutional neural networks (CNNs) have become increasingly popular in recent years because of their ability to tackle complex learning problems such as object detection, and object localization. They are being used for a variety of tasks, such as tissue abnormalities detection and localization, with an accuracy that comes close to the level of human predictive performance in medical imaging. The success is First and foremost, I would like to express my sincere gratitude to my advisor Professor Dr. Navalgund Rao for his guidance, patience, and intellectual support throughout my Ph.D. research. I feel very fortunate to get a chance to work with him who offered invaluable research advice and always provided me opportunities to participate in collaborative research projects and conferences that allowed me to grow academically and intellectually. I am also very grateful to my Committee, Dr. Vikram Dogra, Dr. Guoyu Lu, and Dr. Pengcheng Shi for their time for providing helpful suggestions and feedbacks during my Ph.D. thesis preparation, without whom this accomplishment would not even have been possible. I am very thankful to the Center for Imaging Science for all the support throughout the Ph.D. study. I would like to thank Center for Imaging Science, and the director of the center for imaging science Dr. David Messinger for providing me with a travel grant which allowed me to attend and present my works at Medical Imaging, SPIE, Defense + Commercial Sensing, SPIE, and International Conference on Semantic Computing, IEEE conferences. I would also like to extend my thanks to Elizabeth Lockwood for her countless assistance in my study arrangement during my Ph.D. study.

show abstract

Characterization of lens based photoacoustic imaging system

Cited by 21 publications

References 31 publications

Hand-held optoacoustic imaging: A review

Hand-held optoacoustic imaging: A review

Multiview spatial compounding using lens-based photoacoustic imaging system

Automatic cancer tissue detection using multispectral photoacoustic imaging

Contact Info

Product

Resources

About